Caltrac Tuning Info LOOK HERE

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I take it has never acted this way?
Ok, first off, eliminate the use of the 2step for the time being. It is exasperating the issue.
It looks like you're running out of shock travel on the rear.
How many runs on those tires? I've seen tires hook good, then get at the edge and never hook again. Even with indicators left.
I've heard the guys in Div6 take care of the surface up there, that still true? How do you feel about the track? I don't see a lot of gloss.. no VHT?
BTW, love the car.
The tires have two races on them. The track isn’t great, but everyone else is hooking up.
 
Ok. You know the rear shocks have plenty of travel? it really looks like your shocks are toping out.
Settings haven't changed ?
Maybe take the shock off of the axle and cycle them, in and out, to make sure they're still metering correctly..
 
what leaf springs are you using? Id try leaving the shocks where they are and going up 2PSI on the tires, looks like its crushing the tire and bouncing.
 
Ok. You know the rear shocks have plenty of travel? it really looks like your shocks are toping out.
Settings haven't changed ?
Maybe take the shock off of the axle and cycle them, in and out, to make sure they're still metering correctly..
The shocks are brand new for this year because the old Rancho’s were worn out giving me inconsistent 60’ times. They may be bottoming out, so I should jack it up and check it out. I’m afraid if they extend anymore it’d drag the wheel. I think it’s time for double adjustable.
 
Calvert updated their stock on shocks.. While they used to recommend the Rancho's, (yrs ago) they came up with their own shock, they feel is better than the old rancho's.
Make sure they send you the correct length. I had to return the first ones they sold me. too short.
If you bought the QA1's from Summit, they're usually pretty understanding..


CR Series 9 Way Adjustable Rear Shocks
 
I know it's frustrating, gumper, hope it works out..
 
what leaf springs are you using? Id try leaving the shocks where they are and going up 2PSI on the tires, looks like its crushing the tire and bouncing.
They are the Calvert split monos. I thought about going up on tire pressure to see what happens tomorrow.

Calvert updated their stock on shocks.. While they used to recommend the Rancho's, (yrs ago) they came up with their own shock, they feel is better than the old rancho's.
Make sure they send you the correct length. I had to return the first ones they sold me. too short.
If you bought the QA1's from Summit, they're usually pretty understanding..


CR Series 9 Way Adjustable Rear Shocks
I assumed they just rebranded the ranchos. Didn’t know it was their own shock. Almost bought them, but thought the QA1s would be better.
 
I assumed they just rebranded the ranchos. Didn’t know it was their own shock. Almost bought them, but thought the QA1s would be better.

That is what they told me, and I heard it from others too. Seems I heard they are reworked, valving wise, and similar to the Rancho's.
 
Hey, gumper, check out post #34 in this thread. Good info on shock adjustment.
I will keep that in mind when I go test my new converter..
 
Put the bars back in the bottom hole, 1 flat of pre load, shocks at 9, tire pressure at 12.25, launch 3000. Picked the tires a bit, and a 1.52 60’.
 
what track is that ?
That is High Line Drag Strip in Malta, MT. Also known as Phillips County Motorsports. Way north east Montana. It’s only the second time I’ve been there.
Yea man! Looks alot better! is that what you are looking for now?
Yeah that’s about right I guess. I sure wish I could carry the tires a little higher, but that’s probably something I need to fix with more power.
 

I gave up on the QA1 rear shocks. Put the old Rancho adjustables back on for this race set at 8. Car hooked and pulled the wheels just how I wanted it too. Probably lost 4 important races this year due to traction issues.
 

I gave up on the QA1 rear shocks. Put the old Rancho adjustables back on for this race set at 8. Car hooked and pulled the wheels just how I wanted it too. Probably lost 4 important races this year due to traction issues.



KICK *** to see a 1/4 mile race again !
 
probably not much use to you lightweight racers but our street/strip 3828lbs RR with mono's/caltracs with 1.5 preload/90-10's front and 9-ways on rear on 7 stiff, barely 5" separation with bump stops removed, dead hooks on 10x29 bias Hoosiers@16psi so it doesn't kill the tyre so much and runs 1.43 60's, motor has 720ft lbs, dana 4.10's, low first gear 727 and goes 10.4's in the 1/4 through full exhausts, we are still tuning, also noted that it doesn't need a big burnout, I wanted to try the nickel gap but driver wants preload, seems to be working>

johns launch Good.jpg
 
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probably not much use to you lightweight racers but our street/strip 3828lbs RR with mono's/caltracs with 1.5 preload/90-10's front and 9-ways on rear on 7 stiff, barely 5" separation with bump stops removed, dead hooks on 10x29 bias Hoosiers@16psi so it doesn't kill the tyre so much and runs 1.43 60's, motor has 720ft lbs, dana 4.10's, low first gear 727 and goes 10.4's in the 1/4 through full exhausts, we are still tuning, also noted that it doesn't need a big burnout, I wanted to try the nickel gap but driver wants preload, seems to be working>

View attachment 1715592269
Footbrake ??
 
Yes f/brake only leaving@1800rpm....and now down to a 10.35 best....2 flats preload..bottom hole, this was on sunday, last time out for us this year, could only manage a 1.45 60, cold weather/track (10 deg) but with good DA....600ft.
 
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I finally figured out a decent tune for my Caltracs.
67 Barracuda, small block, complete Caltrac setup with mono leafs and Calvert shocks front and rear.

Bottom hole, 1 flat preload driver side, 2 flats preload passenger side.
Rear shocks set on 6.

It should go faster, but current best is 1.50 60' (with an extra 130 lbs in the car). I'm guessing it will do a 47-48 when I take the weight out....but we will see. This setup has produced a nice clean launch (both wheels coming off the ground even) with a decent 60'. Still testing, will post again if I can improve on this.

Link to a current launch pic.
http://motolenzphotos.com/dragracing/Mopar-Cut/P2Street-Trophy/IMG_7535.JPG
My setup from 8 years ago is still working today with more power. Currently 1.38 60' times, foot brake, leaving about 2500 rpm....no drama, leaves straight every time.

The more I read and talk to folks, it seems like cars with T-brakes and radials have a tougher time finding a good setup.
 
My setup from 8 years ago is still working today with more power. Currently 1.38 60' times, foot brake, leaving about 2500 rpm....no drama, leaves straight every time.

The more I read and talk to folks, it seems like cars with T-brakes and radials have a tougher time finding a good setup.
My setup from 8 years ago is still working today with more power. Currently 1.38 60' times, foot brake, leaving about 2500 rpm....no drama, leaves straight every time.

The more I read and talk to folks, it seems like cars with T-brakes and radials have a tougher time finding a good setup.

Think I finally found a decent setup with the Caltracs and a transbrake
 

Think I finally found a decent setup with the Caltracs and a transbrake

That's GREAT! What was the final piece to get it right? Shock adjustment, or did you just lower the launch RPM?
 
That's GREAT! What was the final piece to get it right? Shock adjustment, or did you just lower the launch RPM?
I went to a pro bracket radial
And moved the front spring eyelet to the lowest setting which raised the tear of the car but lowers the instant center.
Here’s a terrible picture that should help.
Side note
Another leaf spring transbrake mopar guy
Jeff with silver w8 904 combo was a huge help with getting it in order and to be honest that is a under statement I was really close
To putting a set of ladder bars on it
251AB1EF-AADD-41A1-872F-BDED9065F838.png
 
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