Building a S̶t̶r̶o̶n̶g̶ ̶3̶5̶0̶ 383 for Frank the Tank…

Actually, question - if I start with the TDC mark at the current (maybe not correct) zero mark, how many turns of the balancer should it be till the piston stop stops the piston..? Just one yes??

Yes, the piston will be up again in almost 1 turn of the crankshaft, just not necessarily on the compression stroke.
It depends on where it was when you started.
 
Yes, the piston will be up again in almost 1 turn of the crankshaft, just not necessarily on the compression stroke.
It depends on where it was when you started.
Thanks. Yes ok, so do the finger over the hole thing to ensure compression stroke and then almost 1 turn. I'll try that.
 
With the spark plug out, use a 1/4" wooden dowel or pencil to "feel" the top of the piston.
Start with the engine at about 20 degrees BTDC and try to touch the piston top.
If you can't, then rotate it 5 degrees clockwise and try again. Repeat until you can, then
install the piston stop, screw the center rod in until it touches. The engine is a 383 SBC.
It is possible, but I find it hard to believe that the piston stop will not contact.
Mark the balancer to whatever mark you are using for ZERO on your timing pointer.
Then rotate the engine CCW until it gently stops again. Mark balancer again.
TDC (zero) is halfway in between the 2 marks.

As I am typing this, I am wondering if the valves would contact the stop, from being screwed in so far.
That is if you did not loosen the rockers for the cylinder you are checking.
That is probably another reason that Grumpy said to loosen all the rockers and remove all the spark plugs.
 
Ok th
With the spark plug out, use a 1/4" wooden dowel or pencil to "feel" the top of the piston.
Start with the engine at about 20 degrees BTDC and try to touch the piston top.
If you can't, then rotate it 5 degrees clockwise and try again. Repeat until you can, then
install the piston stop, screw the center rod in until it touches. The engine is a 383 SBC.
It is possible, but I find it hard to believe that the piston stop will not contact.
Mark the balancer to whatever mark you are using for ZERO on your timing pointer.
Then rotate the engine CCW until it gently stops again. Mark balancer again.
TDC (zero) is halfway in between the 2 marks.

As I am typing this, I am wondering if the valves would contact the stop, from being screwed in so far.
That is if you did not loosen the rockers for the cylinder you are checking.
That is probably another reason that Grumpy said to loosen all the rockers and remove all the spark plugs.
Cool thanks. that makes sense. That was the plan.

I'm concerned that the valves may contact also.. I've tried to find pictures that clearly show the hole (I feel like the plug hole is quite flat), but loosening the rockers will help:)..
 
tools10.jpg
 
less than one full 360 degree rotation, then back, less than one full 360 degree rotation
 
tools10.jpg


IF THAT BOLT IN THE PISTON STOP EXTENDED AN ADDITIONAL 1.5"FURTHER INTO THE CYLINDER
I'M FAIRLY SURE IT WOULD HAVE BEEN HITTING THE PISTON AND THUS FUNCTIONING AS DESIGNED

you buy a 6" threaded bolt, screw it into the plug body
threadbolt.jpg


with similar thread pitch and thread, that fully threaded bolt about 3" of that bolt extending past the spark plug base,into the cylinder, at that shallow angle, it would be preventingthe piston from reaching TDC
 
tools10.jpg


IF THAT BOLT IN THE PISTON STOP EXTENDED AN ADDITIONAL 1.5"FURTHER INTO THE CYLINDER
I'M FAIRLY SURE IT WOULD HAVE BEEN HITTING THE PISTON AND THUS FUNCTIONING AS DESIGNED

you buy a 6" threaded bolt, screw it into the plug body
threadbolt.jpg


with similar thread pitch and thread, that fully threaded bolt about 3" of that bolt extending past the spark plug base,into the cylinder, at that shallow angle, it would be preventingthe piston from reaching TDC

I can see what you're saying. That picture is not my head. In this picture, which is my head:



It looks to me like a steeper angle on the chamber wall and flatter path for the piston stop. Yes?
 
when using a piston stop in a cylinder head to locate TDC,
the angle of the spark plug,
threaded hole center-line,
in relation to the cylinder bore center-line,
has little to do with combustion chamber outer wall angle,
or combustion chamber shape ,
volume or design in general
but the shallower the angle the longer the piston stop length,
would need to be, to extend below the upper bore edge,

enough for the piston to hit it during its rotation past TDC.

IF you do some research you'll find,There are two points which are usually considered while designing an engine's cylinder head and combustion chamber.

  1. The Spark plug will usually be located as close too the center of the cylinder's center-line in the combustion chamber as other design factors will allow to shorten the distance the ignition flame must cover, during combustion, the less distance the shorter the burn in theory and shorter time frames reduce detonation potential, shorter flame travel , helps as it ultimately tends too reduce detonation even at high compression ratios.
  2. spark plugs tend too be located near to the exhaust valve region so that the flame front travels from the hottest to the coolest part which ensure lower end charge temperature and hence no self ignition of end charge.
ONE OF SEVERAL REASON,S HEMI ENGINE'S
CAN GENERALLY RUN HIGH COMPRESSION ,
WITH A BIT LOWER TENDENCY TO DETONATE
hemisp2.jpg

hemisp1a.jpg
 
Last edited:
Do you reckon that the wall of the chamber on my heads (below) looks more perpendicular? Maybe the bolt heads in on a flatter angle?

I see what you are saying Jimmy. There is not much of an angle in relation to the piston with your heads (flat, as you define it).
Really nice heads you have there, BTW. The picture I found was actually a Ford head. And Grumpy is right, as always, if your
piston stop is not long enough, then you should be able to use a longer bolt in the center for it to make contact. Just be sure to
rotate gently - you do not want to bend anything! And loosen the rockers enough to "twist" them aside of the pushrods so the
valves are disabled.
 
Jimmy,

We need an update..... good or bad we want know !!! We also want to help if we can !!!
 
Jimmy,

We need an update..... good or bad we want know !!! We also want to help if we can !!!

Hi Rick!

Yes, I have been absent for a long time, only occasional check ins to see what's happening on the forum.. A lot has happened since I was last about, both in life and with the car... I'll try to write a few updates this week. I have a few things I want to ask about anyway.. :) Get some input from you guys on next steps with Frank..
 
Ok.. Let me catch you gentlemen up on where Frank the Tank and I are up to now… Get comfortable.. It’s going to be a long story..


I probably have to go back to about August 2016.. Actually sooner.. After a trip home to New Zealand Easter (March) 2016, I decided that it might be time to move home to NZ permanently from Melbourne Australia, where I had been living for 10 years. That required convincing both my Australian girlfriend and my ex-wife (who is from NZ) + two kids (born in Australia), that it would be good for the kids and us to all relocate… It didn’t go down well initially, but after a few months, everyone got on board and it was agreed that both households would move to NZ.. After much logistical wrangling I managed to get two large shipping containers organised, one for the two household’s contents and one for two cars (my girlfriend’s new Mazda hatchback, and Frank). I contemplated selling Frank at that stage, but my smart partner, Rach, forbid it, as she said the only time I smile is when I was driving Frank.. Fair enough. And a good call, because high chance the $$ for the sale would have been spent on furniture and appliances in NZ, if I had it in my pocket..


So, back to August 2016. At that stage Frank was still running a tired 307 and a powerglide. I had an 80% rebuilt 383 in the garage and a th350 (of unknown condition) to replace these. After some consideration as to how to get the lot across the sea, I decided (for better or worse) that I wanted the engine and trans swap to be done before we moved home end of September. This was mainly due to concern about shipping the engine and parts and more importantly that the engine builder that was helping me was local and I didn’t want to have to start again finding a builder in NZ.. Luckily the engine builder agreed to finish building the engine and help me install it before we left…


It’s about here where my control and oversight if the engine build slipped away a bit.. Because timeframes were tight and I was obviously busy finishing up with work and packing two households into containers, I let the builder do his thing.. I left it with him as to the cam choice, gaskets, clearances, etc… and so on… The last bit of the build that I had my hands on was the ring gaps and measuring how far the pistons sat into the block.. I think the builder is one of those kind of guys that may be described as “old school”.. Awesome guy, a bit gruff and blunt at times, very experienced, but, a workshop piled with stuff and little to no record keeping or communication… So, in the rush the engine got complete and sealed up and I have no idea or record of compression ratios, gaskets used, clearances, pushrod length, etc…I know he has no record/recollection of it either… It’s a shame because earlier on I was focused on having the details and using the knowledge here to get it right… Such is life..


Time was rushing by and just three days before Frank the Tank was due to drive (roll) onto a shipping container we started on the engine and trans swap... I managed to sell the old engine and trans to a local guy. It turns out it was a quite hard to find engine out of an HK Holden… not sure who or how it got in my car.. The swap went relatively smoothly with me helping when I could around work and being miscellaneous parts runner.. We reused a lot of the external bits and bobs to save $ and time.. again in hindsight some new bolts and such might have been a good idea… There was a fair bit of fiddling to swap the accessories and stuff, but the engine went in without too much of a fight.. The trans went in easily enough too… Everything was installed and all that was left to do was start and run in the engine, before driving to the port to load the container….. Hands up if you think it went smoothly and it was a happy tale… wrong..


We filled with all the important lubricants and coolants and started the 383 for the first time.. It ran briefly and died… multiple times…. Turned out the coil I had didn’t like the distributor setup… a quick run to buy a new coil and that issue was sorted…. Not the end of the world… We started the engine again and this time it ran pretty well.. but, it started to pop and fart and the workshop filled with an eye burning cloud of fumes.. despite adjustments and fiddling, it got worse and worse… after cutting the engine and checking things and a couple of short tries starting, it was decided that the carb needed a look at.. In hindsight, I should have rebuilt the carb prior to this point… It was a used carb and who knows how long it had been sitting… We found that the power valve was stuck open and pouring fuel into the engine.. Not ideal for a hyd flat tappet cam run in…Had we just damaged my new engine..? The oil was full of fuel… So, new power valve, new oil and much stress on my part, we restarted and ran the engine in… It had oil pressure and much less eye burning… All seemed ok.. But, only the future would tell..


Now, remember that I was on an ever decreasing deadline with a shipping container… So, we dropped the hoist and got Frank on the ground and prepared for his maiden voyage.. There was a small crowd of onlookers who had gathered over the last couple of days in the excitement of getting Frank finished… Start the engine (all good), into Drive…. give it some gas… the right noises, but no movement … More checking and fiddling.. more trans oil…. More noise.. No movement… The TH350 that I had bought as a “pulled from a perfectly running and driving car” trans had no forward gears… it would reverse with some encouragement… but, no forward gears… ANTI-CLIMAX!! and despair… After a few minutes of embarrassment and disappointment, I called a tow truck and got Frank delivered to the port.. and pushed him into the shipping container… I’m sure you guys have lots of sage advice about all the mistakes I made in that month… Regrets…


Fast forward a few months and the relocation to NZ went well, lived out of a suit case for a few weeks, then the containers arrived and all household goods and Frank were transported to my parent’s place. Frank sat for a month or so.. Frank needed to be certified and the government wanted to lighten my pocket for the pleasure, but first we needed to get some forward gears… My father and I removed the TH350 (in the shed on our backs) and delivered it to a local transmission specialist.. Hopefully a minor issue and we’re back on the road… Nope… The trans guy said that the transmission had not had forward gears for a long time and was beyond a rebuild due to the case being worn out/damaged… The only (within budget) solution was to locate a new rebuilder TH350 and start from scratch. I explained that the car was a cruiser that would hopefully head to the track occasionally.. They rebuilt it with that in mind.. I’m not sure what they did specifically, but once it was returned and installed, Frank had all the gears he was supposed to and I could drive him up and down the road.. The TH350 had been pretty good so far and one of my current areas of investigation is shift points for WOT and the kickdown.. more on that later.


Once Frank was mobile, I trailered him to the certifier and that went with no issues. I then drove him home. It was evident that the 2” straight exhaust was not at all up to the new 383, choking and crackling along. I had to leave Frank to sit in the shed until I located and organised a local exhaust builder to put new system in. I now have a full 2.5” system with an X crossover and some great sounding mufflers. I really like how it turned out and he put a cut-out up the front that I remove when at the track (unclear if this adds a performance advantage.. but, it sounds faster..). It also has a join near the diff to allow the middle section to be removed if needed. I’m happy with the exhaust. The only issue to address at some stage is a droning sound which is at worst at idle… The massive trunk floor resonating is to blame.. Not a big deal though..


So, at that point I had a car that ran and drove, sounded cool and moved pretty well… I was finally happy to cruise about. We still hadn’t done more than a basic tune with limited tools at home and it was obvious that I was not seeing the performance expected from a strong 383, but Frank was on the road..


By chance my younger brother won a heads up drag racing competition at a Mazda/rotary convention near us in his 3rd gen RX7 that does high 10s (the acceleration of his car make me sweat…). His prize was a voucher for a dyno tune with a specialist rotary shop.. He didn’t need it as he had a builder already, so he gave me the voucher.. The guys had experience with all engine types, so were happy to help me out.. Unfortunately, the tired 10 bolt open diff wouldn’t play nice with the dyno, so we could only ensure that the tune was close and I was not risking any damage driving Frank hard.. He told me to come back when I had a limited slip diff…


Shortly after that I took Frank to his (our) first drag racing day.. whoop! I was equal parts excited and shitting myself and had a great day.. After a few runs with traction on only one tire and letting the TH350 do it’s job, I managed a best time of 15.3… fast enough to make me happy for a first timer and left with room to improve and chase.. The day ended with a split heater hose..


Next on the agenda was a posi diff and sticky tires… I managed to find a 12 bolt needle in a small haystack that is NZ and had it tidied up and a posi installed. It had 3.3 gears, which I decided at this stage to keep as Frank is really just a cruiser and increasing the gear would increase the $$ and the cruising RPM… Of course I am open opinions about diff ratios for the future.. I also managed to pick up a set of used ET streets on a set of the heaviest steel rims in the universe… they were cheap and would provide the traction I figured I would need.. The tire guy that I spoke to the other day said that the rims were originally used for stock car racing and were not helping my performance any.. add it to the list of potentially expensive upgrades to leave till I’m chasing bee’s dick sized performance gains..


I returned to the rotary specialist for another attempt at the dyno tune. He started out very enthused, but this seemed to dry up.. maybe he was just having a bad day, but really all he did was run it up on the dyno a few times and make a few minor tweaks to timing and one change of jet size for cruise economy.. He said all was looking good and that was it…. What a let down.. But, I couldn’t really argue, since it was a freebie.. When we took it for a quick spin he commented that with the figures on the dyno, Frank should be able to spin tires easily, but either the convertor and/or the trans were not quite right… The figures he gave me from the dyno were 415 ft/lb torque and 285hp.. Unfortunately, he had the dyno software recording something other than RPM, so the print out he gave me doesn’t tell me at what RPM my peak figures are happening.. I’m feeling like I have had a pattern of slightly disinterested and disorganised people working on my car…. At some stage soon hopefully I can get another dyno tune with a V8 specialist who is keen to tinker and get the best performance…


I had another day at the drags shortly after and managed a new PB of 14.6!! the traction made a big difference and the PB run happened when for an unknown reason the trans dropped back down to 2nd (it would usually shift through to 3rd quickly) part track and took off.. Which showed that shift points were important to more speed…


After more research I decided that the lack of tire spinning was a result of an overly loose convertor… (I should have fiddled with the trans at that stage too, as now I think it was probably both..) The convertor I had was a used B&M torkmaster with a rated 3000 stall.. The info from B&M says that the 3000 stall is rated at 250ft/lb or so torque, so I imagine it was locking up well above that and hence the torque being lost to slippage until higher revs, maybe past peak…? I bought and installed a Hughes GM25 torque convertor which is rated at 2500rpm and matched the cam card for my cam recommendations. The new torque convertor really livened Frank up around town.. I can now do a small skid, but no smoky burnouts so far… Oh, I forgot to mention that until about this point, (which is a few weeks ago), the lokar column shift linkage to the TH350 was too short and I could only get drive.. not 1st or 2nd.. I fixed that too. Can manual shift all gears.


Also, throughout the last year and a bit, Frank has fouled plugs pretty badly… I need to do a compression and leak down test in the next little while.. My suspected culprits in no particular order are… rings didn’t seat due to the fuel that poured into the engine during run in, bad valve seals, oil through the pcv valve (I have baffles), intake manifold gasket leak and/or the wrong power valve… I will post pics of the plugs this week.. the plugs in it now are new, they drove an hour each way to the track and about 10 runs over two days.. I’m keen on opinions and advice.


Ok.. thanks for your patience.. what a marathon post… Weekend before last I went drag racing. Two days of bracket racing, the first day was a nostalgia drags meet and the second was a club championships, in which teams or four try to win a team bracket racing comp.. This was the first time racing with the new convertor and the trans being able to manual shift… I installed a new tachometer, but it ended up being faulty.. just my luck.. so, nothing but guesswork for the shifts… Made more difficult by having not heard Frank doing 5500rpm… The first run was disappointing, as the new convertor didn’t result in a faster time… all that time and $$ for naught… But, then I tried launching in 2nd, letting the trans do the first shift and I do the 2-3 shift.. Immediately hit a 14.3! PB and it was so noticeable now, that the trans when left to it own was hitting 3rd by ¼ track… Next I started in 1st and manual shifted to 2 and 3.. 14.158! Now we’re talking… The next run I managed a 13.999! Frank the Tank is a 13 second race car! Yus! I’m pretty pleased with that. My Dad’s 66 Belair with a 427 BBC and TKO600 manual trans does pretty consistent 13.5s and he has done a 13.1 once.. Now that I’m within ½ second of what he usually runs, he’s all of a sudden talking about NOS kits… ha! Got him running… Of note, Frank sucks at burnouts… not sure if front brakes were too weak or it’s a tuning issue, but my burnouts were lame… short and then Frank would grip and take off… In saying that I never once lost traction at the start line..


Right… So, present day.. I’m super happy with a 13.99. I need to look into why plugs are fouling pretty bad and fix that… I need to adjust the shift points on the trans, I’m pretty sure I can do this easily after researching the governor calibration process. I need to hook up the trans kickdown linkage as I’ve gotten mixed opinions on if it effects shift points for WOT, such as a drag run. I’ve got a friend who has a connection to one of the respected old school V8 tuners in town, who has a dyno. Hopefully he can spend time with me getting the carb tuned and distributor curve optimised and run on the dyno. I might get him to look into the plug fouling too.. I don’t have tools for leak down and compression tests yet.. I have a line lock to install before next summer and will upgrade from a single to dual brake master cylinder then too. Also, Frank will be out of action over winter (which is almost here) while I fix some rust under the radiator support near the battery and replace all the front suspension bushes to decrease the tendency to wander and swerve on country roads..



Thanks for reading if you go to this point.. I've probably missed heaps.. I’m super keen on any feedback from you guys on the obvious tweaks I can do to gain horsepower and speed at the track.. I’m hoping there’s still plenty to be gained from relatively inexpensive upgrades and adjustments before I spend a lot more $$$. I have missed the forum and hopefully can hang out more..
 
Ok.. Let me catch you gentlemen up on where Frank the Tank and I are up to now… Get comfortable.. It’s going to be a long story..


I probably have to go back to about August 2016.. Actually sooner.. After a trip home to New Zealand Easter (March) 2016, I decided that it might be time to move home to NZ permanently from Melbourne Australia, where I had been living for 10 years. That required convincing both my Australian girlfriend and my ex-wife (who is from NZ) + two kids (born in Australia), that it would be good for the kids and us to all relocate… It didn’t go down well initially, but after a few months, everyone got on board and it was agreed that both households would move to NZ.. After much logistical wrangling I managed to get two large shipping containers organised, one for the two household’s contents and one for two cars (my girlfriend’s new Mazda hatchback, and Frank). I contemplated selling Frank at that stage, but my smart partner, Rach, forbid it, as she said the only time I smile is when I was driving Frank.. Fair enough. And a good call, because high chance the $$ for the sale would have been spent on furniture and appliances in NZ, if I had it in my pocket..


So, back to August 2016. At that stage Frank was still running a tired 307 and a powerglide. I had an 80% rebuilt 383 in the garage and a th350 (of unknown condition) to replace these. After some consideration as to how to get the lot across the sea, I decided (for better or worse) that I wanted the engine and trans swap to be done before we moved home end of September. This was mainly due to concern about shipping the engine and parts and more importantly that the engine builder that was helping me was local and I didn’t want to have to start again finding a builder in NZ.. Luckily the engine builder agreed to finish building the engine and help me install it before we left…


It’s about here where my control and oversight if the engine build slipped away a bit.. Because timeframes were tight and I was obviously busy finishing up with work and packing two households into containers, I let the builder do his thing.. I left it with him as to the cam choice, gaskets, clearances, etc… and so on… The last bit of the build that I had my hands on was the ring gaps and measuring how far the pistons sat into the block.. I think the builder is one of those kind of guys that may be described as “old school”.. Awesome guy, a bit gruff and blunt at times, very experienced, but, a workshop piled with stuff and little to no record keeping or communication… So, in the rush the engine got complete and sealed up and I have no idea or record of compression ratios, gaskets used, clearances, pushrod length, etc…I know he has no record/recollection of it either… It’s a shame because earlier on I was focused on having the details and using the knowledge here to get it right… Such is life..


Time was rushing by and just three days before Frank the Tank was due to drive (roll) onto a shipping container we started on the engine and trans swap... I managed to sell the old engine and trans to a local guy. It turns out it was a quite hard to find engine out of an HK Holden… not sure who or how it got in my car.. The swap went relatively smoothly with me helping when I could around work and being miscellaneous parts runner.. We reused a lot of the external bits and bobs to save $ and time.. again in hindsight some new bolts and such might have been a good idea… There was a fair bit of fiddling to swap the accessories and stuff, but the engine went in without too much of a fight.. The trans went in easily enough too… Everything was installed and all that was left to do was start and run in the engine, before driving to the port to load the container….. Hands up if you think it went smoothly and it was a happy tale… wrong..


We filled with all the important lubricants and coolants and started the 383 for the first time.. It ran briefly and died… multiple times…. Turned out the coil I had didn’t like the distributor setup… a quick run to buy a new coil and that issue was sorted…. Not the end of the world… We started the engine again and this time it ran pretty well.. but, it started to pop and fart and the workshop filled with an eye burning cloud of fumes.. despite adjustments and fiddling, it got worse and worse… after cutting the engine and checking things and a couple of short tries starting, it was decided that the carb needed a look at.. In hindsight, I should have rebuilt the carb prior to this point… It was a used carb and who knows how long it had been sitting… We found that the power valve was stuck open and pouring fuel into the engine.. Not ideal for a hyd flat tappet cam run in…Had we just damaged my new engine..? The oil was full of fuel… So, new power valve, new oil and much stress on my part, we restarted and ran the engine in… It had oil pressure and much less eye burning… All seemed ok.. But, only the future would tell..


Now, remember that I was on an ever decreasing deadline with a shipping container… So, we dropped the hoist and got Frank on the ground and prepared for his maiden voyage.. There was a small crowd of onlookers who had gathered over the last couple of days in the excitement of getting Frank finished… Start the engine (all good), into Drive…. give it some gas… the right noises, but no movement … More checking and fiddling.. more trans oil…. More noise.. No movement… The TH350 that I had bought as a “pulled from a perfectly running and driving car” trans had no forward gears… it would reverse with some encouragement… but, no forward gears… ANTI-CLIMAX!! and despair… After a few minutes of embarrassment and disappointment, I called a tow truck and got Frank delivered to the port.. and pushed him into the shipping container… I’m sure you guys have lots of sage advice about all the mistakes I made in that month… Regrets…


Fast forward a few months and the relocation to NZ went well, lived out of a suit case for a few weeks, then the containers arrived and all household goods and Frank were transported to my parent’s place. Frank sat for a month or so.. Frank needed to be certified and the government wanted to lighten my pocket for the pleasure, but first we needed to get some forward gears… My father and I removed the TH350 (in the shed on our backs) and delivered it to a local transmission specialist.. Hopefully a minor issue and we’re back on the road… Nope… The trans guy said that the transmission had not had forward gears for a long time and was beyond a rebuild due to the case being worn out/damaged… The only (within budget) solution was to locate a new rebuilder TH350 and start from scratch. I explained that the car was a cruiser that would hopefully head to the track occasionally.. They rebuilt it with that in mind.. I’m not sure what they did specifically, but once it was returned and installed, Frank had all the gears he was supposed to and I could drive him up and down the road.. The TH350 had been pretty good so far and one of my current areas of investigation is shift points for WOT and the kickdown.. more on that later.


Once Frank was mobile, I trailered him to the certifier and that went with no issues. I then drove him home. It was evident that the 2” straight exhaust was not at all up to the new 383, choking and crackling along. I had to leave Frank to sit in the shed until I located and organised a local exhaust builder to put new system in. I now have a full 2.5” system with an X crossover and some great sounding mufflers. I really like how it turned out and he put a cut-out up the front that I remove when at the track (unclear if this adds a performance advantage.. but, it sounds faster..). It also has a join near the diff to allow the middle section to be removed if needed. I’m happy with the exhaust. The only issue to address at some stage is a droning sound which is at worst at idle… The massive trunk floor resonating is to blame.. Not a big deal though..


So, at that point I had a car that ran and drove, sounded cool and moved pretty well… I was finally happy to cruise about. We still hadn’t done more than a basic tune with limited tools at home and it was obvious that I was not seeing the performance expected from a strong 383, but Frank was on the road..


By chance my younger brother won a heads up drag racing competition at a Mazda/rotary convention near us in his 3rd gen RX7 that does high 10s (the acceleration of his car make me sweat…). His prize was a voucher for a dyno tune with a specialist rotary shop.. He didn’t need it as he had a builder already, so he gave me the voucher.. The guys had experience with all engine types, so were happy to help me out.. Unfortunately, the tired 10 bolt open diff wouldn’t play nice with the dyno, so we could only ensure that the tune was close and I was not risking any damage driving Frank hard.. He told me to come back when I had a limited slip diff…


Shortly after that I took Frank to his (our) first drag racing day.. whoop! I was equal parts excited and shitting myself and had a great day.. After a few runs with traction on only one tire and letting the TH350 do it’s job, I managed a best time of 15.3… fast enough to make me happy for a first timer and left with room to improve and chase.. The day ended with a split heater hose..


Next on the agenda was a posi diff and sticky tires… I managed to find a 12 bolt needle in a small haystack that is NZ and had it tidied up and a posi installed. It had 3.3 gears, which I decided at this stage to keep as Frank is really just a cruiser and increasing the gear would increase the $$ and the cruising RPM… Of course I am open opinions about diff ratios for the future.. I also managed to pick up a set of used ET streets on a set of the heaviest steel rims in the universe… they were cheap and would provide the traction I figured I would need.. The tire guy that I spoke to the other day said that the rims were originally used for stock car racing and were not helping my performance any.. add it to the list of potentially expensive upgrades to leave till I’m chasing bee’s dick sized performance gains..


I returned to the rotary specialist for another attempt at the dyno tune. He started out very enthused, but this seemed to dry up.. maybe he was just having a bad day, but really all he did was run it up on the dyno a few times and make a few minor tweaks to timing and one change of jet size for cruise economy.. He said all was looking good and that was it…. What a let down.. But, I couldn’t really argue, since it was a freebie.. When we took it for a quick spin he commented that with the figures on the dyno, Frank should be able to spin tires easily, but either the convertor and/or the trans were not quite right… The figures he gave me from the dyno were 415 ft/lb torque and 285hp.. Unfortunately, he had the dyno software recording something other than RPM, so the print out he gave me doesn’t tell me at what RPM my peak figures are happening.. I’m feeling like I have had a pattern of slightly disinterested and disorganised people working on my car…. At some stage soon hopefully I can get another dyno tune with a V8 specialist who is keen to tinker and get the best performance…


I had another day at the drags shortly after and managed a new PB of 14.6!! the traction made a big difference and the PB run happened when for an unknown reason the trans dropped back down to 2nd (it would usually shift through to 3rd quickly) part track and took off.. Which showed that shift points were important to more speed…


After more research I decided that the lack of tire spinning was a result of an overly loose convertor… (I should have fiddled with the trans at that stage too, as now I think it was probably both..) The convertor I had was a used B&M torkmaster with a rated 3000 stall.. The info from B&M says that the 3000 stall is rated at 250ft/lb or so torque, so I imagine it was locking up well above that and hence the torque being lost to slippage until higher revs, maybe past peak…? I bought and installed a Hughes GM25 torque convertor which is rated at 2500rpm and matched the cam card for my cam recommendations. The new torque convertor really livened Frank up around town.. I can now do a small skid, but no smoky burnouts so far… Oh, I forgot to mention that until about this point, (which is a few weeks ago), the lokar column shift linkage to the TH350 was too short and I could only get drive.. not 1st or 2nd.. I fixed that too. Can manual shift all gears.


Also, throughout the last year and a bit, Frank has fouled plugs pretty badly… I need to do a compression and leak down test in the next little while.. My suspected culprits in no particular order are… rings didn’t seat due to the fuel that poured into the engine during run in, bad valve seals, oil through the pcv valve (I have baffles), intake manifold gasket leak and/or the wrong power valve… I will post pics of the plugs this week.. the plugs in it now are new, they drove an hour each way to the track and about 10 runs over two days.. I’m keen on opinions and advice.


Ok.. thanks for your patience.. what a marathon post… Weekend before last I went drag racing. Two days of bracket racing, the first day was a nostalgia drags meet and the second was a club championships, in which teams or four try to win a team bracket racing comp.. This was the first time racing with the new convertor and the trans being able to manual shift… I installed a new tachometer, but it ended up being faulty.. just my luck.. so, nothing but guesswork for the shifts… Made more difficult by having not heard Frank doing 5500rpm… The first run was disappointing, as the new convertor didn’t result in a faster time… all that time and $$ for naught… But, then I tried launching in 2nd, letting the trans do the first shift and I do the 2-3 shift.. Immediately hit a 14.3! PB and it was so noticeable now, that the trans when left to it own was hitting 3rd by ¼ track… Next I started in 1st and manual shifted to 2 and 3.. 14.158! Now we’re talking… The next run I managed a 13.999! Frank the Tank is a 13 second race car! Yus! I’m pretty pleased with that. My Dad’s 66 Belair with a 427 BBC and TKO600 manual trans does pretty consistent 13.5s and he has done a 13.1 once.. Now that I’m within ½ second of what he usually runs, he’s all of a sudden talking about NOS kits… ha! Got him running… Of note, Frank sucks at burnouts… not sure if front brakes were too weak or it’s a tuning issue, but my burnouts were lame… short and then Frank would grip and take off… In saying that I never once lost traction at the start line..


Right… So, present day.. I’m super happy with a 13.99. I need to look into why plugs are fouling pretty bad and fix that… I need to adjust the shift points on the trans, I’m pretty sure I can do this easily after researching the governor calibration process. I need to hook up the trans kickdown linkage as I’ve gotten mixed opinions on if it effects shift points for WOT, such as a drag run. I’ve got a friend who has a connection to one of the respected old school V8 tuners in town, who has a dyno. Hopefully he can spend time with me getting the carb tuned and distributor curve optimised and run on the dyno. I might get him to look into the plug fouling too.. I don’t have tools for leak down and compression tests yet.. I have a line lock to install before next summer and will upgrade from a single to dual brake master cylinder then too. Also, Frank will be out of action over winter (which is almost here) while I fix some rust under the radiator support near the battery and replace all the front suspension bushes to decrease the tendency to wander and swerve on country roads..



Thanks for reading if you go to this point.. I've probably missed heaps.. I’m super keen on any feedback from you guys on the obvious tweaks I can do to gain horsepower and speed at the track.. I’m hoping there’s still plenty to be gained from relatively inexpensive upgrades and adjustments before I spend a lot more $$$. I have missed the forum and hopefully can hang out more..

Looks pretty Good Jimmy.
Need to verify what spark advance curve is there in the distributor & Base ignition + Mechanical = total WOT spark advance.

I think You have a Holley 4bbl reading.
Street Avenger 4150 or 4160.
Both use a Dashpot vacuum actuated to open the secondary throttle plates.
I just went through it on my 770 cfm Holley Street Avenger...Bad dashpot rubber diaphragm.
Hard to diagnose till you take the damn apart...
Holds the secondary throttle blades open part ways driving causing fuel nozzle drips.
Not enough to cause huge fuel mielage drops.
Secondaries never fully open . Feels good but you know deep down power is lacking yet.
$15 part gave me easy 50 Hp yesterday once I installed it.
 
Vacuum secondary Holley carbs are supposed to be used on Heavy GM cars like Your Chevy & my 63 Gp.
But full Mechanical 4150 Holley 4-bbl can be used with good tuning no problem.
 
I was having spark plugs foul out random.
Switch around cylinders.
Figured valveguides main culprit since my 1965 Olds 425 is all original never rebuilt.
No more fouled plugs.
Ran Flawless today driving 150 miles rountrip to work & back home.
Like a Brand new EFI LS Car but much more Torque & HP WOT.

Oil stayed Clean too.

$15 dollar Part from Holley...Summit Racing.
Holley vacuum secondary Rubber bellow dashpot assembly.
 
Looks pretty Good Jimmy.
Need to verify what spark advance curve is there in the distributor & Base ignition + Mechanical = total WOT spark advance.

I think You have a Holley 4bbl reading.
Street Avenger 4150 or 4160.
Both use a Dashpot vacuum actuated to open the secondary throttle plates.
I just went through it on my 770 cfm Holley Street Avenger...Bad dashpot rubber diaphragm.
Hard to diagnose till you take the damn apart...
Holds the secondary throttle blades open part ways driving causing fuel nozzle drips.
Not enough to cause huge fuel mielage drops.
Secondaries never fully open . Feels good but you know deep down power is lacking yet.
$15 part gave me easy 50 Hp yesterday once I installed it.

Hi Brian!

Yep, thanks. I need to verify my advance curve for sure. I rember last year getting as far as trying to verify TDC, figuring out my piston stop wasn't long enough and then forgot all about it... Still to be done. Good reminder.:rolleyes:

Yes, I have 4bbl Holley. Its a strange one, list number 4118-s 725cfm vac secondary, electric choke. Think they used to be used on mustangs. I'll look into the diaphragm too. Thanks.
 
I was having spark plugs foul out random.
Switch around cylinders.
Figured valveguides main culprit since my 1965 Olds 425 is all original never rebuilt.
No more fouled plugs.
Ran Flawless today driving 150 miles rountrip to work & back home.
Like a Brand new EFI LS Car but much more Torque & HP WOT.

Oil stayed Clean too.

$15 dollar Part from Holley...Summit Racing.
Holley vacuum secondary Rubber bellow dashpot assembly.

So you think it's maybe fuel fouling..? I'll post some pics of the plugs later in the week.. They smell a little fuelly.. But not strong.. and quite wet. The guy that did the dyno tune indicated that my vacuum level may need a lower value power valve, but the AFR numbers weren't bad, so didn't bother changing it... But, like I said he kind of lost interest..
 
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