Help a noob with ladder bars ... please

[Mactizen]

Hey guys i am new to posting here been lurking for a while trying to soak up knowledge before posting up questions. I have an 84 Mazda RX-7 with an all iron turbo V6, the car puts down rite around 500/500, I have a turbo 400 well built to handle it with a pro- brake (4 tenths).

To the suspension and the problems. Last year the car had old stock rx-7 springs and ran a best 60' of 1.45 (12psi launch) on an 26x8 inch wide etdrag and basically no suspension adjustments 1 degree pinion angle down. This year the car has coilovers in the back with 100/200 progressive spring rates and damping adjustable shocks. Ladder bar front is set to the 2nd hole from the top (i have 4) and 1 degree pinion angle down. This past weekend my best 60' was a 1.50 (20psi launch) on a 28x13.5 et street. THe car hooks for about 10 feet then MASSIVE tire spin for about another 40-50 feet. This is on a track thats notoriously not that sticky and sometimes downrite nasty to hook-up, i would love to blame the track but the day i was there lots of 9.50 cars were hooking and going, i raced a dew people with 1.38ish 60's so the track was hooking for some. The car gets very little weight transfer (if any) wich i plan to let the preload off the rear springs to try and let them compress more next time out.

Anyway what would you suggest to start trying to hook better and taking advantage of my ladder bars? Most threads i read say to just lower the front of the bar down. I want to make sure of my adjustments before i make them as the track isnt that close.

usefull info
car wieghs 2835lbs with me in it and its a bit front heavy
tried between 12 and 8 psi in the tires (best around 9)
tried big burnouts small burnouts and no burnout (best with tires hotter)
treid foot brake and trans brake same results
aprx 105" inch wheelbase
my front suspension is NOT designed for drag racing i'm in the process of trieg to find a more suitable front spring atleast, its basically a roadcourse setup so i could get camber adjustment to make the skinnies stop hitting the fender.
looking for wieght transfer and or more hook

pics so you get an idea of the car, sorry they are big




any help appreciated

[David Lemmond]

What kind of shocks do you have and what is the angle of your ladder bars now? Level, up, or down?

[Mactizen]

The ladder bars are near level, and i'm running QA1 12 way adjustable shocks.

[Mactizen]

Just took a measurment it's 2 degrees down at the front.

[David Lemmond]

It's hard to say, but for sure tighten the rear shocks next time out if they are loose now. Going down with the bars may help, if you do that, leave the shocks like you have them now. After a few hits, tighten them up and see what happens. It's a crap shoot without seeing the car leave or having something similar to go by but it sounds like alot of cars I've worked on and this helped.

[Mactizen]

thanks for the tips, one question i havn't seen an answer to is this. If i lower the front of the ladder bar do i then adjust the pinion angle back toward 1? or leave it where ever it goes.

also i have a video of the right quarter/rear when i launch i am trying to get a buddy to rip that for me and i will post it up.

[David Lemmond]

If you have 1 degree of pinion angle now, I would just drop the bars one hole and run it. You can have up to around 4 and be ok. I think dropping the bars one hole will not give you more than 3 more degrees.

[Dave Morgan]

Greetings,
Your comment about the weight transfer causes me to point to your rear spring rate and the fact that you have a road racing type spring it in. Be careful tuning the QA-1s as they are a little quirky. It's not a huge problem, but be aware that somewhere between the third and seventh click, the car may not respond as the trends have indicated. If you se the car do somthing different in this range of adjustments, just keep going in th direction you wre headed. This anomoly will only occur at one setting, if it occurs at all.
I hope this helps.
Dave

[Mactizen]

Finally got to the track, lowered the ladder bar one hole, felt good from the get go. The track was prepped a bit better then usuall for this 3 day event but it gave me lots of time to play.

Ended up going with less preload on the rear springs and i was getting within 1/2 inch of full compression of the shock (ziptie method) so i was happy there. Also set the damper to 2 clicks from full soft and was working pretty good. Got my new set of front springs installed on the saturday afternoon and things got better still!

Wound up with a best 60' of 1.44 wich isn't all that much better but atleast it's better, i still have more to play with and still want to go to a better prepped track. The car was hooking hard but off the line they seem to stop spraying and i had some other racers telling me they think i was spinning till the 1/8.

Anyway never seen this before!!!!!!



Thanks for the help, it's only looking up from here.