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My car has been a best of [email protected] with a horrible 60' before this weekend. Just like tons of other guys, I had a car that had been lowered with stock mounting holes for the control arms and it did not want to 60' very well. Call TRZ and I ordered the body side adjustable mounts and the rear end side lower control arms mounts to be able to make instant center/anti squat adjustments. I have not installed the upper mounts, but did install the lowers and went back to the track. The car had a instant center length of 41.54'' and anti squat of 97.49% before. After only being able to install the rear adjustable control arm mounts I had to run them uphill to the body side in order to be able to get a short IC and more antisquat. Those positions gave me antisquat of 150% and instant center length of 37.23''.

The first two passes on this set-up netted bests for the car of 1.31 and 1.28 in 60' but both spun around 100'. The track wasn't that great and it also seems like hew power/boost comes in all at once when I have to leave on that low of a boost level. I left the line at 6 and 6.5 lbs of boost for those two runs.

Car has:

-QA1 single adjustable front shocks and one turn from full tight

-Strange double adjustable rears at 2 on extension and 5 on compression from full loose.

-x275 pro on 12 inch wheel

-16 psi in tires

-3.23 gear I believe (car should go 190+ mph in the 1/4 and 3.23 lets me do that at reasonable rpms)

-Makes 1380 rwhp on my dyno


Here is the videos in order 1.31, 1.28:

http://vid58.photobucket.com/albums/g275/black98ws6/IMG_0094_zps2eb6defd.mp4

http://vid58.photobucket.com/albums/g275/black98ws6/IMG_0094_zps2eb6defd.mp4


It looks to me as if the rear shocks could be tightened on the compression to keep the rear end from bouncing right back up after the initial hit.

The second thing I have concerns about it that if I am going to have to leave on this low of a boost level I can not get it to mechanically build boost fast enough to accelerate as quickly as I would like. Should I retard timing and raise the boost so it is the same power level and then ramp both back in? It just seems that when I leave on 6 psi it lugs on the converter while climbing slowly, then when it is all in at the 70-80-90 foot mark it comes on strong and would knock the tires off of it on a marginal track. Opinions?
 

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Tighten the rear compression a few clicks.

And I'd suggest a tighter front strut (like the Menscer AFCO's, Santhuff's, or Strange Pro Mod DA's)... or just install a heavier rate front spring to slow the weight transfer down, which is only a band aid, you'll eventully just need better struts. It looks like the front is jumping up too quickly... and for only a 1.31 or high 1.28 60 foot you're not really getting after it yet. It'll only jump up sooner the quicker you try to go. We've picked up big numbers on a local guy's nitrous Ultra Street Car by getting him to switch from QA1 singles to the Strange DA's, and that's way less power than you have. He went from in-consistent high 1.28's or so down to consistent 1.21's and even a few teens in there on the Ultra Street mandated old skool 3754R 275 radial just from switching struts.

And on the turbo stuff (all 275 radial high powered stuff really), like you're thinking, power management is a huge difference. If you have the boost come in too slow and then ramp in real fast, it'll tend to blow the tires off at that point. You're best off trying to get the boost in sooner so it doesn't ramp up real fast 1.5 seconds into the run, or however long into the run.
 

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Discussion Starter #3
Tighten the rear compression a few clicks.

And I'd suggest a tighter front strut (like the Menscer AFCO's, Santhuff's, or Strange Pro Mod DA's)... or just install a heavier rate front spring to slow the weight transfer down, which is only a band aid, you'll eventully just need better struts. It looks like the front is jumping up too quickly... and for only a 1.31 or high 1.28 60 foot you're not really getting after it yet. It'll only jump up sooner the quicker you try to go. We've picked up big numbers on a local guy's nitrous Ultra Street Car by getting him to switch from QA1 singles to the Strange DA's, and that's way less power than you have. He went from in-consistent high 1.28's or so down to consistent 1.21's and even a few teens in there on the Ultra Street mandated old skool 3754R 275 radial just from switching struts.

And on the turbo stuff (all 275 radial high powered stuff really), like you're thinking, power management is a huge difference. If you have the boost come in too slow and then ramp in real fast, it'll tend to blow the tires off at that point. You're best off trying to get the boost in sooner so it doesn't ramp up real fast 1.5 seconds into the run, or however long into the run.
Thanks for the reply!

I do have limiters on the car and they are adjusted fairly loose, do you reccomend to tighten them up some? I dont have a problem buying front struts I am just trying to test and learn as much as possible along the way. I do still have a turn to go in the front struts also.

Obviously I am trying to get the boost/power in as quick as possible, its just that when leaving on such a small amount of boost it mechanically cant make it any quicker, thats why I posed the question of leaving on more boost with less timing, and ramping both it. Not that you misunderstood just reiterating my question. Thanks!
 

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Tighten the strut all the way then... but QA1 singles are gonna be too soft a shock for a 150 mph X275 car. And limiters will just make you hit full travel sooner, which most likely will make it spin sooner too. Don't use the limiters until it starts to carry the front too high or too far out.

And as far as making more boost sooner... we only do suspension so I don't really know whats involved in making that happen. We generally just tell the people we're helping with at the track to make it do this or that, and they make the adjustment on the laptop. Maybe somebody here knows... or you can post that question in the turbo / boosted section. Could just be in the tune, or could be a converter thing.
 

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What do you have for trans? Glide? 1.80? Also what is some info on the converter? List some more info,and we can get you started on the boost controller. You may fine what TRZ said, our tune-ups may put you on the bumper and that's our mild tune-ups, with the front suspension you have! We will give it a try tho.... I also think you may not be in the right ballpark with the rear gear also.... Start with trans and converter for us. Thanks
 

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Discussion Starter #6
What do you have for trans? Glide? 1.80? Also what is some info on the converter? List some more info,and we can get you started on the boost controller. You may fine what TRZ said, our tune-ups may put you on the bumper and that's our mild tune-ups, with the front suspension you have! We will give it a try tho.... I also think you may not be in the right ballpark with the rear gear also.... Start with trans and converter for us. Thanks
Rossler 2.10 3 speed, Pro-torque converter, not sure on size or options, both pieces came in the car when I bought it.
 

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Anthony, you can change the power curve quicker by ramping the timing curve than you can the boost curve. Leave on more boost but pull the power back with a timing retard(s).
 

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Maybe have someone with a 3 speed on 275's chime in to see what they are doing in the 1st 100'. Rear gear? I'm sure there doing it a little different.
 

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Discussion Starter #9
Anthony, you can change the power curve quicker by ramping the timing curve than you can the boost curve. Leave on more boost but pull the power back with a timing retard(s).

Yeah, thats what I figured, I just havent heard a ton of people talking about doing it.
 
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