60ft, 330ft help
 

i think our car is couple hundreths off in the 60ft and about a 10th off in the 330 and about a 10th off in et for the mph. its all Calvert rear suspension including shocks. the front has limiters and some 3 way adjustable cheesy shocks which need replaced but its not in the budget at the moment. my curiousity is to you guys with leaf spring and caltrac cars do the cars like the front end loose or if it hooks do you try to tie it down. i've always been under the impression that if your hooking wheel stands aren't ideal but it also seems like i've read that alot of cars run better when you let them fly. car is 69 amx 28x10.5 pro bracket radial, 4.10 gear 5500 converter weighs 3264 it could probably use a 4.56 or more gear but that'll be tested later.

https://www.youtube.com/watch?v=f_R6PA7dbt8

Re: 60ft, 330ft help
 

Shallow staging should be worth a few hun.

Re: 60ft, 330ft help
 

thats good advice the car rocks a bit on the trans-brake in the video i couldn't really feel it in the car but its visible, launch rpm is another thing thats only 3200 on the 2 step i've read that that you should leave as low as possible if the car doesn't stumble is there truth to this or should i try more rpm?

Re: 60ft, 330ft help
 

where does it make peak power? where do you shift it at? where does it currently cross at? No reason you cant go solidly low 50's high 40s with that mph. And 1.38-1.42 sixtys.

Re: 60ft, 330ft help
 

It hasn't been dynoed so we are chasing shift points a bit. According to A.H. Adkins some of you may know him runs yellow amx in SS/B he did the head work and is Familiar with the combination he said it should peak at about 7600 and to shift it at 7600, although we ran a 7.00 index class a few weeks back and tried short shifting it alot to slow it down and down to about 6500 and it never dropped off any from lowering the shift point. and that pass it crossed at 6700 if i remember correctly. i'm really seeing and understanding the value in data recorders these days

Re: 60ft, 330ft help
 

Methinks that you've already solved your problem. Put the gears in it first.

Re: 60ft, 330ft help
 

I agree with this too but i wanted to see if there where any other hints or things that i was missing.

Re: 60ft, 330ft help
 

Converter is too tight at 5500 for a 7600 shift. Needs more gear as well ... 4.88.

Re: 60ft, 330ft help
 

the convert flashes closer to 6000 but yes agreed needs gear i'm not sure if 4.88s would be too much i wish there was 4.60-4.70 ish gear for an 8 3/4

Re: 60ft, 330ft help
 

Like 4 weeks ago you couldn't get down the track and several posters tried their best to figure out your problem. Now your concerned over .020 in your 60' times? How about you make some laps and figure some of this stuff out yourself ?

Re: 60ft, 330ft help
 

Fair enough, sorry if i annoy you, yes we've had alot of issues with this car and i appreciate the help and listen to what you guys have to say i don't think i've ever been rude or unappreciative. also i enjoy talking about racing and seeing what people who've spent years getting the absolute most out of there combinations have to say, theirs a reason i come to this board to ask questions, its because i have tons of respect for stock and superstock racers, and admire what you guys do. i can lay off but i just like the advice and to keep sharing whats going on, this has been a big learning experience. and now that the cars coming around were still trying to find some et that should be in there and who better to ask. yeah i had already thought about gears, sue me i asked i question i had a inkling of an answer too, in order to stir some discussion and see if anybody had any other hints.

Re: 60ft, 330ft help
 

What low gear ratio is in the transmission?

Re: 60ft, 330ft help
 

its just the stock 2.45

Re: 60ft, 330ft help
 

I still think the converter is off.....or the engine tune somewhat. Even with lack of gear, the thing should sixty harder......at least .07. Converter is I'd bet 80-90% of the sixty. Gear is the rest. But if the timing/jetting isnt right, that could explain alot also.

Re: 60ft, 330ft help
 

What's the stroke on the engine?

Re: 60ft, 330ft help
 

engine stroke is 3.85

Re: 60ft, 330ft help
 

Torque converter like the other man said. I have a 23* sbc 3.875 stroke crank with a set of cylinder heads that flow 326 @0.700lift. 3250 pd car goes 1.27 60ft N/A with a 8.94 starting line ratio on a 28 x 10.5 bias M/T. Your starting line ratio is 10.05. if your'e optimum shift is at 7600rpm the observed stall should be around 6200 with a 3sp transmission, maybe a cats whisker more. I wouldnt change the gear without a converter adjustment. No way, it won't go down consistently.

Re: 60ft, 330ft help
 

Pfordamx: I don't mind trying to help out a racer that has a problem. Just think you need to go down the track many more times and tune what you already have. You seem too quick to start jumping into parts swapping. Flog what you have, evaluate, then make one change. This takes time and patience. Good luck.

Re: 60ft, 330ft help
 

Rims
Tires
TQ Converter
Gears
Trans


425 HP runs 7.0 @ 3250. 1320 divided by 124.7 = 10.58.

Re: 60ft, 330ft help
 

Pfordamx- No doubt you need a convertor and gear change to get your 60 fts. to improve. One thing you may want to try....stay off the two step and leave at 2000-2200. This may let the convertor 'work' a bit harder and let it flash a bit higher...might give you some insight before you spend any cash.

Also, be aware that Stockers and Super Stock cars have very aggressive convertors. You may, or may not, want that same aggressive convertor in a bracket application. Spending some time correlating similar et's/60 fts. for cars that run similar times to yours and looking at the 60's for similar e.t.'ing Stock/SS cars can be pretty revealing.

P.S. - AMX's are 'way cool.....:)

Re: 60ft, 330ft help
 

I've been intending to test it off the foot brake at a low rpm like 2200 and to raise it up to 4500 or 5000 just for testing purposes. the main thing were running into is we built a car with the idea of a bracket car then found a local heads-up series that has an NA class that the car falls very easily into rules wise and its pretty enjoyable, but it leads us to look for more and more performance where if it was just a bracket car 10.70s wouldn't be too bad in a local NO E class. but the car has yet to be bracket raced except for one index race that we used as more a test and tune then really trying to run the #

Re: 60ft, 330ft help
 

A trip to an engine Dyno will -would save lots of time and money.Important data like peak Horsepower RPM and peak Torque RPM would be used to choose rear gears and torque convertor .Also would know actual HP output.Bill C.

Re: 60ft, 330ft help
 

So went to a 1/8th mile race over the weekend with 4.56s installed and the car responded well it went a 1.43 sixty foot and 6.62 in the 1/8th at 3700ft da and 95% humidity from a previous best of 6.80 and a 1.48 sixty i was pretty happy with that the quickest run of the night in our class was a 6.57 so it seems to be in the hunt just need to tune about another .10 out of it and should be good for a short amount of time.

Re: 60ft, 330ft help
 

I think you would be doing yourself a favor running a 30X9 CO6 Hoosier radial slick, 29.5 version. You really should try that, there is a reason people run that tire on a automatic stocker.

Re: 60ft, 330ft help
 

i'll look for a hoosier in that compound but we are limited to 28x10.5 per this local headsup classes rules. we could run a 28x9 if they sold one.

Re: 60ft, 330ft help
 

The Mickey Pro Bracket Radial is available in 28 x 9.

Personally, I prefer the Hoosier C07 92.5" radial to the C06 tire. With the C06 tire being designated 'lightweight', I figure that the weight savings most likely come in the form of less tread depth.

I can get 250 passes from a set of the C07 radials by doing a light, no line-lock burnout and they work flawlessly.

If you can't go over 28" tall, then I'd try the Mickey.

Re: 60ft, 330ft help
 

we have 28x10.5 pro bracket radials on the car and they hook and there very stable, if there the fastest tire we could run i don't know and we have managed to brake them loose a few times, if i was bracket racing every weekend and needed something that would hook no matter what this would not be the tire . but I don't have basis for comparison with this combo they are what we started with, so couldn't tell you if there any better or worse than any other tire.

Re: 60ft, 330ft help
 

I would suggest that the problem isn't the tire. Make your car work on that tire and you will be MUCH better off for it.

In 23 seasons, my bracket/Super Street Nova has had one set of bias-ply tires on it, and it won't see another set. If offered a free backhalf job, I would decline. I firmly believe that the radial tires are the secret behind the car working as well and as consistently as it does.

Re: 60ft, 330ft help
 

Were working on it, could be were just not used to having enough hp for the car to be sensitive things like starting line placement and the amount of heat in the tires in the burnout and things like that there is a big difference in 11.70s and 10.50s and its been a learning curve.