renegade intake? for cross fires

Indycars said:
Don't remember, what rockers did you buy? Makes you wonder if one will come
apart early..
Click to expand...

Depends what rockers your asking about
The ones I plan on using for camshaft break-in and then tossing are "ProComp" and those ones destroyed two studs already!
Also note that I have already had them installed and ran them for a few thousand miles, while I don't trust them long term, I think they would be perfect for the camshaft break-in.
Also they are roller tip only.

And the full rollers I just bought @ 1.65 are "Scorpion race series".

I was realllly close to buying the compcams gold but the wife started cracking down on me for money spent... and they had a sale at summit.. :rolleyes:


Indycars said:
Got pics of the process. Lots of people have used those.......just saying politely or
trying to anyway!.
Click to expand...

I have some pictures on the camera, however I have been way to lazy. :(

Indycars said:
Expensive, but worth every penny I'm sure!.
Click to expand...

I sure hope so, I'm looking forward to seeing how it handles with the new steering!

Indycars said:
It's not quite that simple. If you could read the dial indicator, push down on the valve
until contacts the piston for the 30° before and after TDC, now that might work. You
might have the right idea, but you didn't explain with enough detail that we could tell
for sure. We can't assume that you are going to do something so very important, so
error on the conservative side and call your hand on it ...... sorry.
Click to expand...

That was pretty much my thought.
The graph Grumpy posted is very helpful.
My first thought was to move the crank a few degrees and check it, few more degrees and check it again, and continue like that for a good hour or so...

Now I'm thinking the same thing, but focusing on the 30 degree mark before and after TDC to start.

I was also trying to figure how the heck to get my magnetic dial indicator base to stick to something, but that metal strip in the image is brilliant. :D

Next thing I need to get are pictures of the OEM springs on the new heads, they are a bit smaller dia. than the new springs...
I'm thinking I might be ok to run the engine like that for 20-30min but I'll refer to the experience here...
 
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I also scored a march pulley set (pn 4445) from ebay for $100.
It's a reduced ratio to free up a little hp, but mostly I bought it because it was shiney... :cool:
It includes the main crank pulley, water pump, and alt.

I think it will tie in the valve covers and the intake a little bit better, but I'll have to wait for the final assembly to know for sure.

Image from the ad,
upload_2015-12-4_5-17-26.png
 
Gibbles said:
Now I'm thinking the same thing, but focusing on the 30 degree mark before and after TDC to start.
Click to expand...
I would still verify with modeling clay, it been done 1000's of times and is a
trusted way to measure VTPC.

Gibbles said:
Next thing I need to get are pictures of the OEM springs on the new heads, they are a bit smaller dia. than the new springs...
Click to expand...
I would be concerned with valve springs binding. Be sure and measure before
you turn it over.
 
http://garage.grumpysperformance.co...ting-up-the-valve-train.181/page-2#post-54091

http://garage.grumpysperformance.com/index.php?threads/valve-train-clearances-and-problems.528/

http://garage.grumpysperformance.com/index.php?threads/rocker-push-rod-wear-issues.9815/

http://garage.grumpysperformance.com/index.php?threads/semi-fool-proof-cam-sellection.82/

drawsdf.jpg


ValveSpringClearance01.jpg
 
Ok on to my next question, valve spring diameter...

I'm wanting to run my oem springs from the original head for camshaft breakin, however they are a little smaller than the springs that came with the edelbrock heads.

The way it looks installed...
upload_2015-12-6_17-15-39.png
 
I'm more worried about coil bind. Have you tried to turn it over by hand and see
if you have obvious coil bind. When all the coil touch each other, then it's no
longer a spring, but a solid bar that's not going to yield. Something else is going to
bend or break.

If you have hydraulic lifters, then this might be more difficult to tell ......... Grumpy
we need your help here please !!!!
 
you may be better off just using the factory installed valve springs for the cam break-in procedure rather than swapping springs , the lower load rate may seem to be an advantage but any clearance, or binding issue instantly negates that potential theoretical advantage as your taking a chance of screwing up clearances,and if it binds it will nearly instantly destroy the cam/lifters
valve springs can use cups on outer diameter or stepped seats on inner diameters to locate and center springs,
you still must verify the coil bind stack height and installed height and verify that at full valve lift theres still an additional .090 more, minimal additional clearance.
properly clearanced valve trains with proper lubrication rarely have wear issues
valvespringseats.png


reading links and SUB LINKS can prove to be remarkably informative
http://garage.grumpysperformance.com/index.php?threads/removing-valve-seals.4283/#post-44287

http://garage.grumpysperformance.co...per-valve-spring-seats-shims.1005/#post-15534

http://garage.grumpysperformance.com/index.php?threads/valve-springs.9613/#post-50601

http://garage.grumpysperformance.co...ting-up-the-valve-train.181/page-2#post-54091

http://garage.grumpysperformance.co...train-clearances-and-problems.528/#post-53235
 
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I installed the oil pan and primed the oil system after adjusting the valves over the weekend.

I think I can check for full lift with my oil pump primer, however if not I can clearly see the lifters, and I should be able to adjust for the clearance I can identify from the top of the lifter to the retaining clip as a base.

Looking through the threads I don't see anything targeting the valve spring cup size difference.

So just to confirm this is ok as long as I have enough spring clearance...

The side spacing in the cup marked with come crudely drawn double arrows.
upload_2015-12-7_8-46-27.png

eta: answered above; Thanks Grumpy!
 
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Gibbles said:
So just to confirm this is ok as long as I have enough spring clearance...
Click to expand...

Yes I think you will be OK with the extra spring side clearance. You should be
fine as long as you don't have any other clearance issues.

Did you say you are using the stock rocker arms, if so then be sure the check the
slot to stud clearance. Lift can be high enough that the slot is not long enough to
handle the extra lift.
 
Not the stock rocker arms, but they are the stock ratio.

I'll confirm the slot clearance, and Grumpy makes a solid argument about a possible bind.

One worry I have is if the spring moves in the cup and it does bind, however I'm only planning to run it for a few minutes but it only takes a second to kill the camshaft
 
Still moving along at a slower pace, Christmas is over and I'm getting back to it.

One issue I also noticed was the OEM springs were shorter than the edlebrock ones, and the edlebrock heads have a deeper spring pocket.

Installing the oem springs gave me a much lower spring rate than the original heads had, meaning I could press on the top of the valve with my hand and push the valve in a bit.

That got me thinking about valve float... so I decided to scrap the idea of running the OEM springs for camshaft break in.

Also those cheap roller tip rocker arms, I noticed that the pushrods were held in different locations depending on w hat rocker I looked at...

Issue being that even though the test set I used to verify push rod clearances to head were fine, a few of the rockers would come very close to rubbing on the push rod hole in the head...

So over the weekend I swapped out the springs to the edlebrock springs, and I installed the scorpion 1.65 ratio rockers and confirmed my push rod to head clearance is good...

I also took the OEM valve covers and managed to get atleast one opened up, those oem cast covers are very tough... :)


Next hurdle is the exhaust system, namely headers... the OEM header manifold has a very small exhaust inlet, smaller than what the edlebrock exhaust ports have.

From what I was reading having the header inlet smaller than the exhaust port is a very bad thing... I was hoping to run the factory exaust for a short time, mostly during camshaft break-in and for me to pay down my credit card for a month or two...

Thoughts?
 
From what I was reading having the header inlet smaller than the exhaust port is a very bad thing... I was hoping to run the factory exaust for a short time, mostly during camshaft break-in and for me to pay down my credit card for a month or two...
Thoughts?
Click to expand...

I think 99.8% of the guys in this hobby are forced to work on a rather limited budget, your certainly not alone in that regard, so I would not be all that worried about breaking the cam in or running it awhile with restrictive stock exhaust manifolds,
while its certainly true it will cost you peak horse power below about 4000 rpm its restrictive effect won,t be all that critical if the rest of the exhaust systems not all that restrictive, keep in mind headers are designed to increase cylinder scavenging efficiency and as the rpms increase both the volume of the exhaust gases exiting the engine (goes up rapidly) and the time lag between cylinders firing changes (gets far shorter) thus the volume of gases and the cross sectional area restricting the gas flow becomes much more restrictive and the ability of the inertia of those gases effect to help drag the mass of following exhaust pulses tends to become more effective in a properly tuned header and collector as the rpms increase
ONLY IF THE EXHAUST SYSTEM PAST THE HEADERS COLLECTOR IS VIRTUALLY NON RESTRICTIVE, TO EXHAUST FLOW IN THE HEADERS DESIGNED RPM OPERATIONAL POWER BAND,
which is almost always found in the 3500rpm-7500rpm range and covering generally a 1500rpm-2000rpm sweet spot where its most efficient.
your engines rpm range,compression, displacement, cam timing, header primary length and cross sectional area, plus the fuel/air ratio,intake manifold design, carburetor, or throttle body flow rates, ignition timing and several other factors will effect your engine performance and how effectively headers scavenge the cylinders
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stockhd5.jpg



flowarea.jpg

torquecurvespipe.gif

torquetri.gif

A COUPLE HOURS SPENT READING CAN SAVE YOU MONEY AND EFFORT
 
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that engines looking rather nice! CONGRATS!

as to the headers, the slightly smaller primary tube size would result in a bit more low rpm torque at the cost of a bit more restrictive upper rpm power,
the larger hooker header is generally a bit better designed, for fit and plug wire clearance, and is likely to give a bit more power over 5000rpm, and since your very UN-likely to notice the slight loss in lower rpm torque to near the extent you might want the extra upper rpm power, I think the only reason to buy the smaller header would be related to the lower initial cost.
think about it a second.....if you want the car to go faster what are you going to do?
if your like most guys you step on the throttle to open the engine to allow more air flow,want to go faster?
you allow even more air and fuel to enter the engine, RIGHT?
at what point did you notice that couple extra ft lbs of low rpm torque the smaller header might provide?
if you did have enough torque to spin the tires you lost that power to slippage, if its not quite enough you added a bit more rpm to further accelerate the car!
youll keep adding additional engine rpm until either the power increase starts to drop,
off due to the restriction to air flow effectively making even more power,
or your valve timing and piston speed limitations force a change,
to the next lower gear to keep the engine within its physical rpm limitations.
To take full advantage of the new intake manifold design, Id suggest the larger header,
the difference won,t be huge but it should be noticable and it will likely add a couple hundred rpm to the engines useable power band, over the slightly more restrictive smaller headers.
but keep in mind NO HEADER will function to its full potential if the exhaust system behind those headers , restricts the exhaust flow!
headers are only effectively scavenge over a fairly narrow rpm band and in the case or your intake manifold and those hooker headers thats fairly well matched.
RPM_RangeLog.gif

volumetric efficiency and torque.gif

Stoich.gif

http://garage.grumpysperformance.co...gine-to-match-the-cam-specs.11764/#post-55651

http://garage.grumpysperformance.co...hing-the-drive-train-to-the-engine-combo.741/

http://garage.grumpysperformance.co...trans-choice-made-correctly.11697/#post-54833

http://garage.grumpysperformance.co...late-gear-ratios-and-when-to-shift-calcs.555/
 
I think the 1 5/8 inch headers are likely to last longer since they are made
from 14 gauge material while the other one is made from 18 gauge. Also
might be slightly quieter.

What's the difference in primary length .... one says "full length" and the
other says "mid length" ?

Love that engine porn. looking very very nice I must say !!!
 
Thanks, I have been making very good use out of that harbor freight 6in polisher I picked up. :)

And they are both Full length, I'm not sure if that "mid length" is a typo or what.

The hookers are also "tuned".

Last month the hooker headers were on sale, I see that's over with now...

I was also looking at matching them up with this system...

http://www.amazon.com/1984-1991-Corvette-Exhaust-Pipe-Output/dp/B000GEYH9U

I also would like to install a pair of exhaust butterfly dumps... :D

Thoughts on the header coatings?
there is a hooker system that would need header paint for a bunch less $$, but from what I have been finding the ceramic coating offered is worth the difference in price...
 
yes the ceramic coating reduces under the hood heat and extends the working life expectancy of the headers noticeably


related info
http://garage.grumpysperformance.com/index.php?threads/header-paints-and-coatings.6086/#post-28624

http://garage.grumpysperformance.com/index.php?threads/calculating-header-design.185/

http://www.pontiacracing.net/js_header_length1.htm

rough calc on ideal primary length 1 3/4"diam.
(ID BET THE HOOKERS ARE CLOSER TO THE IDEAL LENGTH)
350head1.png


rough calc on ideal primary length 1 5/8 "diam.
350head2.png
 
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Making my way through the reading, I was also looking at what it would take me to toss an exhaust together and then I ran across this system.
http://www.melrosecorvette.com/1984...er-system-no-egr-no-air-add-catalytic-option/

With the ceramic header coat it comes to $1,156.
Compared to piecing it together I save a bunch of time trying to fit it up, and it's about the same price as the CC system with headers...

The CC system is 2 1/4, this is 3in and then narrows near the rear to 2 1/2

upload_2016-1-14_14-13-27.png

thoughts?
 
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