From 144 to D1-SC
- Thread starter DorianL
- Start date
your link doesn,t work!
I can swear on this forum, right?
OH MY FUCKING GOODNESS!!!
Only twice have I ever laughed like a madman driving back from a test ride: when I tossed the 250L6 for a 400SBC and today.
This thing is insane and I haven't really got on the gas yet.
Initially I was disappointed because the engine seemed to be loading up as I teased the throttle... Then I figured... This is not a roots, am going to lose some low end. Sooooo I started cruising around at 2500 rpm and then getting on the gas. WOW!!!! It seemed to pick up and fly. The centifugal whine is awesome!
Now get this... I never even got into boost. The road just felt too narrow. I never got past 1/3 throttle. Too scary.
So I chuckled like a madman on the way back with a ride that is over-jetted, coservatively timed, no boost and... I had the secondaries disconnected. :mrgreen:
OH MY FUCKING GOODNESS!!!
Only twice have I ever laughed like a madman driving back from a test ride: when I tossed the 250L6 for a 400SBC and today.
This thing is insane and I haven't really got on the gas yet.
Initially I was disappointed because the engine seemed to be loading up as I teased the throttle... Then I figured... This is not a roots, am going to lose some low end. Sooooo I started cruising around at 2500 rpm and then getting on the gas. WOW!!!! It seemed to pick up and fly. The centifugal whine is awesome!
Now get this... I never even got into boost. The road just felt too narrow. I never got past 1/3 throttle. Too scary.
So I chuckled like a madman on the way back with a ride that is over-jetted, coservatively timed, no boost and... I had the secondaries disconnected. :mrgreen:
SEE! I told you its a TOTALLY different deal than that old pathetic roots mini supercharger!
once you get the tune worked out you'll have a power curve slightly better than my corvette on nitrous, and tires will go up in smoke at 60mph like I might have mentioned, get that secondary on the carbs hooked up, get your jetting correct and roll into the carb with your foot on the throttle from a rolling start, don,t stomp the pedal to the floor,as that only results in a bad launch, hold on tight and aim for the horizon,and watch the revs build as the tires scream for mercy which tends to put a BIG GRIN on your face
once you get the tune worked out you'll have a power curve slightly better than my corvette on nitrous, and tires will go up in smoke at 60mph like I might have mentioned, get that secondary on the carbs hooked up, get your jetting correct and roll into the carb with your foot on the throttle from a rolling start, don,t stomp the pedal to the floor,as that only results in a bad launch, hold on tight and aim for the horizon,and watch the revs build as the tires scream for mercy which tends to put a BIG GRIN on your face
GREAT! but what ever it shows its bound to leave a great deal of room for future tweaking to get more power as your just getting started.
Right-o... I am off to the dyno tomorrow. I did a few second gear runs on the highway. My primaries are 80s and the secondaries are 95. Still at WOT my A/F is around 13.5:1 Sooo, I am going to drill out the jest a little more. Odd, the jets should not be that big.
If the AF is ok, I'll bring up the boost retard from 25 degrees slowly to 36. With alcohol injection I should be able to get that. Likely I will stay at 34 tho'
Burned up to ribs on my 12 rib belt. I presume it was not tight enough. Rats... the belt squeals at the top of WOT. I hope I will be able to find a replacement here.
BTW, I see close to 10 PSI at WOT.
If the AF is ok, I'll bring up the boost retard from 25 degrees slowly to 36. With alcohol injection I should be able to get that. Likely I will stay at 34 tho'
Burned up to ribs on my 12 rib belt. I presume it was not tight enough. Rats... the belt squeals at the top of WOT. I hope I will be able to find a replacement here.
BTW, I see close to 10 PSI at WOT.
ID bet the horsepower numbers increased noticeably from the old roots set up even before you get it sorted out!
My dyno numbers are:
468 RWHP
638 BHP ?
637 Ft/lbs of TQ
Note... I was only seeing 7.5 PSI. I think the belt already degenerated to the point it is no longer capable of pushing 10 PSI. And I know for a fact I have seen 10 PSI. I think I am a bit rich too...
How do you read this plug?
There should be another 30 - 50 HP in there...
468 RWHP
638 BHP ?
637 Ft/lbs of TQ
Note... I was only seeing 7.5 PSI. I think the belt already degenerated to the point it is no longer capable of pushing 10 PSI. And I know for a fact I have seen 10 PSI. I think I am a bit rich too...
How do you read this plug?
There should be another 30 - 50 HP in there...
well the first thing ID say is
CONGRATS ON THE IMPROVEMENTS SO FAR!
yes the plug appears to be running a bit rich at the lower rpm levels but it looks like its cleaning up at times looking at the ground,(I wish I could see the porcelain and electrode clearer)
but I would suspect that's not a major problem.
obviously the belt needs to be replaced,before other factors can be accurately judged and since Im not sure of the type of belt used it might need to be upgraded
if your running a narrow serpentine belt your fighting a HOPELESS BATTLE
http://www.blackmountainprecision.com/bb1.htm
http://www.blackmountainprecision.com/C ... -block.htm
http://www.stefs.com/products/gilmerbeltcharts.htm
these guys sell cog belt drives
http://www.millerspeed.com/
a cog gear drive belt/pulleys might be preferable
ID suspect at this point its mostly belt slippage holding you back,so ID work on that first
having that dyno peak out at only 5500rpm shows theres much more in the future, once you can hit and maintain about 6000rpm, without slipage, on the drive belts I would suspect things will improve and you MIGHT need more cam duration, but certainly more tuning
CONGRATS ON THE IMPROVEMENTS SO FAR!
yes the plug appears to be running a bit rich at the lower rpm levels but it looks like its cleaning up at times looking at the ground,(I wish I could see the porcelain and electrode clearer)
but I would suspect that's not a major problem.
obviously the belt needs to be replaced,before other factors can be accurately judged and since Im not sure of the type of belt used it might need to be upgraded
if your running a narrow serpentine belt your fighting a HOPELESS BATTLE
http://www.blackmountainprecision.com/bb1.htm
http://www.blackmountainprecision.com/C ... -block.htm
http://www.stefs.com/products/gilmerbeltcharts.htm
these guys sell cog belt drives
http://www.millerspeed.com/
a cog gear drive belt/pulleys might be preferable
ID suspect at this point its mostly belt slippage holding you back,so ID work on that first
having that dyno peak out at only 5500rpm shows theres much more in the future, once you can hit and maintain about 6000rpm, without slipage, on the drive belts I would suspect things will improve and you MIGHT need more cam duration, but certainly more tuning
Yes, I think that belt is nicely burned up. it is even slightly frayed. I think the tensioner was a bilt loose... I was trying to avoid running the bearings of the charger. Now I know. That belt looks expensive. It is a 12-rib.
I think I also need a blow off valve...
When running a duno pull this seem leaner (13.7) until 4500 then it seems from there till 5500 it drops down to 12.6
The percelian is uniformly colored all the way down: dry soot black. Only the strap and a ring around the tip of the electrode are white.
Again, I did a run and shut off immediately.
I think I also need a blow off valve...
When running a duno pull this seem leaner (13.7) until 4500 then it seems from there till 5500 it drops down to 12.6
The percelian is uniformly colored all the way down: dry soot black. Only the strap and a ring around the tip of the electrode are white.
Again, I did a run and shut off immediately.
Oh, one more thing...
my previous TQ curve was very similar to the viper's... a bit taller and broader
However every single point of my new curve is OVER what I had before. Sooo, we did NOT lose any lowend TQ. Perhaps it was just a relative feeling?
my previous TQ curve was very similar to the viper's... a bit taller and broader
However every single point of my new curve is OVER what I had before. Sooo, we did NOT lose any lowend TQ. Perhaps it was just a relative feeling?
ID replace the belt and make sure it will not slip, some BELT DRESSING adds TRACTION,to the contact between belt and pulley and may help
http://kpg-industrial.com/products/belt_dressing
I would NOT try to lean out the fuel/air ratio, that seems to be in a decent range
http://kpg-industrial.com/products/belt_dressing
I would NOT try to lean out the fuel/air ratio, that seems to be in a decent range
DorianL said:
reading plugs is a science, this thread might help
viewtopic.php?f=70&t=202
if the tip on the ground strap is white but the porcelain and rest of the plugs sooty, and your f/a ratio is in that 12.6-13.6 range which is about normal, its usually indicates a fast rise in cylinder temperatures,during acceleration probably due to the ignition advance rate being a bit faster than ideal, and the plugs generally running a bit colder than ideal, ID suggest carefully advancing the base timing but cutting back on the total timing advance so your resulting total timing remains similar, but do it VERY GRADUALLY.
example
if your current total advance is now at 34 degrees and at idle its 8 degrees ID suggest changing the at idle to 10 degrees but changing the springs or distributor weights to maintain the same 34 total, if that works you can try another 2 degrees etc. until the porcelain and ground electrode show a clean burn, but your not having any indicators of detonation, and try to maintain a 12.6 f/a ratio during acceleration and a 13.5 ratio cruising