(Before and after videos of changes inside on page 3 post #45, new PB!, lots of issues fixed!)


Long post, but there is lots of information...


If you're not familiar with the Magnacharger F-Body setup, it requires spacers inbetween the k-member and trans crossmember to get it to fit. I'm wondering if this is causing problems with my suspension geometry or instant center. According to my installer, the pinion angle was still at -2 degrees.

I have over 500 RWHP, MT ET streets, SFC's, LCA's and brackets on the lowest hole, a ground control coilover kit with bilsteins, adj. PHB. I've leveled the car the best I can, it is lowered, I've checked the rear and it is centered and I spin in a straight line. I've experimented with every type of launch technique and tire pressure. I launch slightly off idle and it bogs for a 1.9 and 2.0, just about anything else above and it just blows the tires right off even at 16 psi. Track prep is ok and I have a line lock, the tires are getting hot and I'm in the groove. The car seems to want to orient itself properly on launch, but the weight just won't transfer to the rear and stay there. Yeah my roots is heavy, but I have some weight reduction and any supercharger or turbo setup or iron block for that matter is heavy.

I have a buddy with an almost identical setup (I put it in) and he easily cuts 1.7's NA and 1.6's on spray with 5k clutch dumps and that's it, he is lowered without LCA brackets. He does however have a BMR torque arm, I do not.

I couldn't manage anything better than a 2.0 tonight or a 1.9 last week. Having my car just blow the tires like that is just getting downright embarassing. I have zero traction issues in any other gear. Launch is just killing me, the car won't hook up and reach it's potential which I know has got to be in the 1.7's at least.

The MT's are brand new. I just upgraded from some BFG drags and am not doing any better. Kinda pissed about putting 500 bucks into tires that did nothing. I have a fair amount of seat time too. Been dragging a few seasons.

I'm going to be making some calls to UMI and BMR next week to try and figure this problem out but what do you guys think?

-Instant center issue?
-Do I need an adjustable torque arm?
-What is a torque arm going to do for me anyway? How do they "solve" traction issues?
-Should I move my LCA's to the upper hole and try that?

I'm pretty sure this thing has an 11 sec. run in it at the 6800 DA I'm running at. I've really got my shift points down now and the trap is up there. Everyone tells me the car is strong as ****, it just won't hook up and get moving. Help.

 

What size are they?
How much do you heat them up?

 

265/40 18, I heat them up in 2nd gear until they start to smoke and then roll out. I've never checked them with a thermometer. Like I posted above, I have a linelock and they're getting hot.

BTW, I'm on stock 3.42's.

 

The 18s combined with a **** ton of torque is killing you. Do you have big brakes or something that you can't run a smaller wheel? I don't think there's anything you can do suspension wise to get the current setup to hook. You need some sidewall give.

 

It's a 40 series, doesn't matter if the rim is 18" or 15". Sidewall is the same. I'm not looking to go from a 2.0 sixty to a 1.5 sixty. Guys have gotten better sixties with the same series on a nitto.

I know I should be getting better than what I am. I would be content with 1.7's on an 18" wheel. I know better times are in store with a smaller wheel and tires of the same height.

People have lifted 18's off the ground.

 

maybe you are unloading, do they grab 1st and then spin? Try moving up to the center or top hole on the brackets. If you want to leave really hard in a 6spd you need some bias ply slicks. The mt's are better than the bfg's, so you should do better on just the tire swap alone.I wasted some $$ on a set of drag radials a while back and couldn't do better than a 1.8 60ft. Switched to a 15 qtp and now I can get low 1.6x's and I have a cam only car, no where near the power you have. I would try the lca holes 1st. I hear of guys putting them on the lowest hole and their 60's actually go down.

 

I cut 1.42 to 1.44 60's in a 3,700lbs car w/me in it N/A. A bmr drag bar took me from 1.50 to the low 1.4's. I have 4.11's w/12 bolt. lca's on last hole and pin-is at -2. I run M&H racemaster cheeter slicks. 26x11.5x15 www.intercotire.com My suspen set up is nothing real different then most run on theis site. all the same ****. I heat them up and off a 2-step set between 6,000 & 6,500rpm's. I floor and dump the clutch. the car pulls a nice wheeley and takes off. never bogs or spins much at all. The more you street drive and wearout the tires the less they hook at the track. I also ran the same tire but in a old lt1 16'' rim and still was in the 1.5 60's. goodluck to ya.

 

First, an adjustable TA will help.

Second, are you removing your front sway bar at the track? If not, do so.

Third, to get better 60fts you need more sidewall, a 15" with a 40 sidewall is not the same as an 18" with a 40 sidewall. Im sure you cut decent 60fts with 18s with less power but now you have more power and it will not hook without the sidewall giving some.

Get some prostars and some 26x11.5x15 et streets, an adjustble TA, remove your front sway bar and be sure to burn out in second gear and you should have no problem hitting 1.6 60s and breaking your 10bolt if thats what you are running.

 

that was my problem... i was dead hooking, raising the tires about 6 inches... then unloading on the rear (shitty weight transfer and soft *** suspension) and then spinning, then rehooking...

pissed me off.

 

yeah, I had that problem too. I am no expert and don't have a whole lot of seat time like some of these guys. My first time out on slicks I was cutting 1.63's all day. I put some lca relos on and went back without changing anything else. I was cutting high 1.6's with them on the lowest hole. It felt like it would grab good, then spin a tad after the initial launch. I didn't change them there and haven't went back since. Next time out I will be setting them in the middle hole and see how that works out.

 

if your having unloading issues you.. something that may help.. (temp. fix) is air bags in the rear..

will stiffen it up so your **** isnt so soft.. worth a shot for about 40 bucks or so..

 

I'm having the same problem and an airbag in the pass side didn't really help much. It simply comes down to not having enough sidewall to absorb the drivetrain shock and not transferring weight.

 

Video of my fastest 60 foot, 1.87, spun like hell, this was with the old BFG's and not the MT's though. I have since adjusted my coilover in the rear to level the car out. I get better weight transfer, but was slower.

http://www.youtube.com/watch?v=I_Vz4HzxfZ8

Nah, not really grabbing at all

My buddy cuts better times with his MT ET streets than his slicks. 5k, dump, gone, easy 1.7, 1.6 on the spray. That would be fine with me at this point in time.

I'm not totally sure what unloading is, I suppose you mean losing positive weight transfer? But the higher an RPM I try to launch at, seems that I get less transfer and just spin. I could try the upper hole, have thought about it, but they look level to me. I know some 15's with massive sidewall will help, but mightymouse can cut a 1.33 on 17's and even more tires plus wheels aren't something I'm ready to shell out cash for at this time. I'm not expecting sub 1.5's right away. I would be happy with 1.7's this season. Your 1.8's were better than what I've been getting on MT's. I think something is seriously wrong really.

Why will a torque arm help? Nobody seems to be able to explain what the damn thing does. I don't want to throw 300 bucks at this thing without gaining a tenth at least in the sixty. I know the stock one is flimsy, I've had it off and could bend it with my bare hands, but why will it help me? And are you saying I can't get a better sixty foot with the wheel and tire combo I have now? Because like I said, guys are cutting 1.3's on 17's and I've seen 18's lifted off the ground on a 35 series. I watched vettes cut 1.7's all night long one a 35 series BFG. I'm tired of hearing all this stuff about sidewals. I'm not going for 1.3 right now and I'm actually cutting better sixty foots with alot more power than last season. I think my torque arm and pinion angle might be way off, something I feel is the biggest problem right now. Anyone else agree?

So you got slower with them?

My buddy that launches off the bottle also no longer has them after his moser. I think when I do the torque arm, I will move these up as well. Since I'll have that angle finder I'll be able to check it. -1 degree is what you want I hear?

 

ouch, i thought you were starting your burnout...

you are correct... its when the rear end pops back up because it doesnt have weight on it.. poor weight transfer, suspension, tires, etc..

different tires will def. help, but IMO wont solve that.. you need to focus on your suspension setup.

 

If you watch the vid closely, when the tires finally grab, the nose comes up, but sits right back down immediately afterwards.

As far as suspension goes, what SIMPLE change or parts would you recommend and why?

 

dont ask me... i have traction issues too..

im on stock suspension.. i know how to make the power really good.... just dont know how to get it down!

 

I've watched this video over and over and over again trying to figure out what is going wrong. Some good things that are happening is you can see the spoiler drop on the right, and the driver side front wheel lifts. The beginnings of a good launch are there, it's just not doing it hard enough or staying oriented like that throughout the entire 60 foot. What is going to get more even and constant force down on the rears.

 

how much weight have you taken out? and where?

 

Are you just trying to get your thread count up then?

 

I'm not sold on the sidewall thing yet, not to gain just a few tenths. Not transferring weight though? What are you a rocket scientist?

I'll be calling BMR, UMI, and Madman this week.