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At the very least, start cranking the rear shocks up. Your at #6...Jump to #10 and work your way up to #13. There are worse shocks than QA1, but definitely better ones out there. Like Horndog says, D/A is a better route. If you buy new ones, look at AFCO or better.
I’ve never understood what “ground” has to do with a race car. I look at rocker angle and go from there. Can you get -1.5* from rocker panel angle?
If your at 4 turns base (what is the base pressure and 4 turns? They are not all built the same), if the suspension is right (and it’s not), then I would guess a 5,000 RPM launch would work in bracket mode. If you want to go faster, drop it down 2 more turns AND increase your launch RPM to around 6500.
Your SLR may be a little steep but it’s doable. I would suggest somewhere between a 2.9x to a 3.0x whatever is offered. But if is out of your budget, then what you have will work.
 

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As I understand it, a decent starting line ratio is between 8 and 10. I really think there too much first gear in that trans. I ran a hemi crash box with a 309 first gear, a 29x12.5 slick and a 4.56 gear. Weighing 3400#, traction for me was average at best. I really think your first gear should be switched to the 2.66 that was available, and you'll bring your SLR down into the 12.9 range. Not great, but better.
Clutch cars use far greater SLR than an auto. I know some stockers that are over 15-1
Doug
 

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S.L.R is relevant to H.P.!
 

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My D/S AMX was 15.49 SLR and did just fine on 9”x29.5’s. It’s a chassis shop getting back-halved and new SLR will be 16.32 w/ 14”x31” slicks. As DVW said, SLR should be higher on a stick car, there’s no TQ multiplication like you get with a convertor. The engine makes power, just need to work on the clutch and suspension tune. I have had cheap drag shocks and they work. But every time I’ve bought better shocks, the car tunes better and goes faster.
 

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Discussion Starter #25
My D/S AMX was 15.49 SLR and did just fine on 9”x29.5’s. It’s a chassis shop getting back-halved and new SLR will be 16.32 w/ 14”x31” slicks. As DVW said, SLR should be higher on a stick car, there’s no TQ multiplication like you get with a convertor. The engine makes power, just need to work on the clutch and suspension tune. I have had cheap drag shocks and they work. But every time I’ve bought better shocks, the car tunes better and goes faster.
My D/S AMX was 15.49 SLR and did just fine on 9”x29.5’s. It’s a chassis shop getting back-halved and new SLR will be 16.32 w/ 14”x31” slicks. As DVW said,
At the very least, start cranking the rear shocks up. Your at #6...Jump to #10 and work your way up to #13. There are worse shocks than QA1, but definitely better ones out there. Like Horndog says, D/A is a better route. If you buy new ones, look at AFCO or better.
I’ve never understood what “ground” has to do with a race car. I look at rocker angle and go from there. Can you get -1.5* from rocker panel angle?
If your at 4 turns base (what is the base pressure and 4 turns? They are not all built the same), if the suspension is right (and it’s not), then I would guess a 5,000 RPM launch would work in bracket mode. If you want to go faster, drop it down 2 more turns AND increase your launch RPM to around 6500.
Your SLR may be a little steep but it’s doable. I would suggest somewhere between a 2.9x to a 3.0x whatever is offered. But if is out of your budget, then what you have will work.
My D/S AMX was 15.49 SLR and did just fine on 9”x29.5’s. It’s a chassis shop getting back-halved and new SLR will be 16.32 w/ 14”x31” slicks. As DVW said, SLR should be higher on a stick car, there’s no TQ multiplication like you get with a convertor. The engine makes power, just need to work on the clutch and suspension tune. I have had cheap drag shocks and they work. But every time I’ve bought better shocks, the car tunes better and goes faster.
My D/S AMX was 15.49 SLR and did just fine on 9”x29.5’s. It’s a chassis shop getting back-halved and new SLR will be 16.32 w/ 14”x31” slicks. As DVW said, SLR should be higher on a stick car, there’s no TQ multiplication like you get with a convertor. The engine makes power, just need to work on the clutch and suspension tune. I have had cheap drag shocks and they work. But every time I’ve bought better shocks, the car tunes better and goes faster.
Headed to Quaker Friday night to try some things.
New 10.5w x33" slicks.
Ladder bar bottom hole-3* nose down.
Shocks #6 front
#7 rear.
1/2-turn out of clutch > 3.5 turns.
See what happens. 🤞
 

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Discussion Starter #27
Don't know why it did that

Heading to Quaker Friday night.
New slicks 10.5x33" MTs
Ladder bar in lowest hole 3* nosedown.
Front shocks #6
Rear #7
1/2 - turn out of clutch 3-1/2.
See what happens. 🤞
 

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As you reduce base pressure, you should INCREASE launch RPM. Less base pressure needs the clutch to get slammed into submission. If you loosen the base pressure and lunch RPM is too low, then the clutch will not hold (unless it was way to tight to begin with), it will be under to much of a load.
Usually the problem is the car won’t hook on a low RPM launch BECAUSE the BP is to tight. The BP is loosened and the driver REFUSES to increase the launch RPM because “it wouldn’t hook before at 5,000 RPM and if I go to 6,000 RPM I will surely die when I hit the guardrail” That is the #2 problem. The #1 problem is inadequate throw-out bearing clearances.

And yes...BEST OF LUCK!
 

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Discussion Starter #30
As you reduce base pressure, you should INCREASE launch RPM. Less base pressure needs the clutch to get slammed into submission. If you loosen the base pressure and lunch RPM is too low, then the clutch will not hold (unless it was way to tight to begin with), it will be under to much of a load.
Usually the problem is the car won’t hook on a low RPM launch BECAUSE the BP is to tight. The BP is loosened and the driver REFUSES to increase the launch RPM because “it wouldn’t hook before at 5,000 RPM and if I go to 6,000 RPM I will surely die when I hit the guardrail” That is the #2 problem. The #1 problem is inadequate throw-out bearing clearances.

And yes...BEST OF LUCK!
 

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Discussion Starter #31
Well just got home.
Not a real definitive answer to any of the questions.
1st run. Now that it has tires that work it slipped the clutch on launch.
#2 added 1/2 turn back to base. Left ok but the wheelie bars caught it and it unloaded the tires sending it to the wall.
#3 Raised wheelie bars 4 turns and raised launch RPM to 5,500. Drove through the clutch.
So out comes the clutch to reset ring height and see what has worn..✌
 

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Well your learning! Can you raise or remove the wheelie bars? There are more poorly interpreted results as a result of wheelie bar interference. The gravel pan on a ‘Cuda hangs pretty low.
Did you drive thru the clutch in 1st gear only? Or did you stay on it in all four? If 1st only, you MIGHT get away with adding another +1/2 turn BP. But always, R&R for inspection is the best recipe.
I wouldn’t call tonight a disaster.
 
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Discussion Starter #33
Well your learning! Can you raise or remove the wheelie bars? There are more poorly interpreted results as a result of wheelie bar interference. The gravel pan on a ‘Cuda hangs pretty low.
Did you drive thru the clutch in 1st gear only? Or did you stay on it in all four? If 1st only, you MIGHT get away with adding another +1/2 turn BP. But always, R&R for inspection is the best recipe.
I wouldn’t call tonight a disaster.
Well your learning! Can you raise or remove the wheelie bars? There are more poorly interpreted results as a result of wheelie bar interference. The gravel pan on a ‘Cuda hangs pretty low.
Did you drive thru the clutch in 1st gear only? Or did you stay on it in all four? If 1st only, you MIGHT get away with adding another +1/2 turn BP. But always, R&R for inspection is the best recipe.
I wouldn’t call tonight a disaster.
Well just got home.
Not a real definitive answer to any of the questions.
1st run. Now that it has tires that work it slipped the clutch on launch.
#2 added 1/2 turn back to base. Left ok but the wheelie bars caught it and it unloaded the tires sending it to the wall.
#3 Raised wheelie bars 4 turns and raised launch RPM to 5,500. Drove through the clutch.
So out comes the clutch to reset ring height and see what has worn..✌
Struggling to get a couple things working together.
3,050lbs, 50/50 weight distribution.
4speed/4.88 rear/ ladder bars-parrelel to the ground. Ran a [email protected]/1.32-60ft.
Issue is can't find a range of settings that work pass to pass,week to week etc.
Skates off the line or deadhooks and really rides the bars....sometimes not straight. 🙈
Stiffen front and lower w_bars..no traction.
Loosen or raise bars one pass good one terrible without touching it.
Lost on how to find some middle ground....🙁




Not sure why when I try and answer anything it quotes the last entry.

So the clutch is not the only issue, everything seems to be "on--off"
Deadhooks/spins
Pounds tires/slips clutch.
Goes left/right
Perfect straight riding the bars photo op......
Haven`t made a good pass since I replaced 3 broken valve spring in June.
Was working well with broken valve springs,built in governor ..........:sneaky:
 

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So the clutch is not the only issue, everything seems to be "on--off"
Deadhooks/spins
Pounds tires/slips clutch.
Goes left/right
Perfect straight riding the bars photo op......
Haven`t made a good pass since I replaced 3 broken valve spring in June.
Was working well with broken valve springs,built in governor ..........:sneaky:
Very competitive racers use my clutch hit controllers on adjustable Soft Lok's, even on Nex-Gen's and Boninfante's. They basically remove the weights, crank up the base just enough to hold high gear, then use my external controllers to momentarily hold back just enough base to optimize clutch slip during launch. Being able to control clutch hit intensity independent of RPM eliminates the need to compromise launch energy with a 2-step. A side benefit is the clutch hit after shifts ends up softer without the centrifugal weights, so less energy gets spent creating wheelspeed spikes after clutchless shifts. Far easier to dial in than your current setup, the softer but longer lasting hit you end up with also makes the car less sensitive to chassis/shock adjustments.

Grant
 

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Discussion Starter #35
Ok,so last night more test and tune.....
Clutch is on its last leg....took the last shim out yesterday.
1st pass.
9.96...1.39-60ft. really soft launch. Thought it spun.Camera person filming wrong end of car.🙄
2nd pass. Thinking it was hitting the tire too hard,took a 1/2 turn out of the clutch.
WRONG way.
Really slipped the clutch down track......through away run.
3rd run.
Put a bunch more base,2 turn more than I started with =7.
That worked.
Car went out a couple feet and started climbing.
Went straight,,,which was good.
However having the wheelie bars higher to stop influencing the launch came back into the picture.
Car was pretty high and climbing on the gear change and took a hard bounce and came back up in 2nd a bit.
Smashed the pan some....
But I think it as all starting to show me what it wants.
More clutch, lower w/bars.
At least it finally going straight.
I can tune from here. 🤞
 
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