Test-N-Tune tomorrow **video added***** another update

Hoping to take the car out tomorrow if the weather holds off and get some test passes in. We went tonight but it would not stop sprinkling so they called it off. The car ran a best ever 6.14 at 112.00 last month and we changed the gear out from a 4.10 to a 4.30 and we will see how much it picks the car up tomorrow, I have a feeling we will have to change over to a 4.56 or 4.86 to get the car to run the 6.00 index class but we had the 4.30 already setup so it was easy to change over. Any guesses on how much the car will pick up if any tomorrow? Also has anyone made the same gear change and if so how much did you pick up in the 1/8. The car is a tube chassis 1991 Mustang weighs 2775 with driver. Motor is a 466 CID Aluminum Kaase SCJ heads with a powerglide transmission. Again it ran a best of 6.14 at 112.00 last month best 60ft was a 1.43 or 1.42 (cannot remember) with the 4.10 gear in the car. Will try to get some videos if I can if the new camera will work for me and if someone else is able to get dad in the water-box.

later,
Doug

goodluck Doug ...... hopefully it will net you some single digits

Well guys we are quite disappointed here. Took the car out and ran 4 passes with the new 4.30 gear. The best pass was a 6.30 at 109mph. Not sure what is going on with the car, but after the car running a 6.13 and a 6.18 last time out we were sure the car would run at least a 6.0 something. I will say the car was pulling to the right some all night long, we lowered the leave chip down to 4400 from 4800 and the last pass seemed to pull less but we did not pick up any on the 60ft and than lost about 6 or 7 hundredths to the 330. We are jerking the 4.30 out soon and getting a 4.86 setup for us and hope to take the car back out in a few weeks and maybe than work on the 4 link some and preload it so that it does not pull to the right but not sure what happened to the car, the only changes to the car were the gear and we built a air pan for the car but took it back off after the first pass to have a more closer test to last months. I have one video of the car that was taken with my digital camera(not great quality but you can see it pull right). I will try to get it on soon.

Thanks,
Doug

Here is a video from last night. the car was not pulling as far to the right as it had previously. sorry that it is not the greatest quality but it was taken from a digital video camera so it cannot be focused while in video mode. I do think the car looks pretty good with the new paint, I just wished we could afford a aluminum spoiler for the car I think it would look even better.



thanks,
Doug

Doug did you set the preload with you in the car are someone close to your waite sitting in the driver seat Thats what we had to do on RX 7 to get it leaving strieght it was jumping out like yours and will help alittle on the wheel hop or bounce you have. It just take alittle time to get everything adjusted and strieghten out

466 with aluminum Kaase SCJ heads pushing about 600HP(never dynoed). Probably could use a new converter, it is a PTC I think the stall is 4200 9 inch. Leave chip was 4800 for 3 runs the video run we set it at 4400. The shift rpm was not really set last night we shifted it on a timer since our box crapped out it was set at 3.00 the first run than lowered down to 2.4 seconds by the last run, should have been at 2 or 2.2 for it to shift at the 6500 we usually shift the car at, was getting on the high side chip(7k) for a very short time on most of the runs, was going through the lights at around 6250 or so. Next time out should have a new rpm selector box and will shift it at 6500 and it usually traps at the same 6500. The weather was around 82 degrees until the last run and it was down to 75 but the humidity went from 48 on the first 2 runs to 64 on the last run, barometer held at 103 the whole day. It was a decent track last night(it is a heads-up track night run 4.70, 5.70, 6 and 7 flat classes) but not as nice as the last time out so I figured the car with the new gear would run a 6.08 or so compared to last months weather. This is all on gas and it was about 4 degrees hotter and the humidity was 43 when it ran a 6.13. I really wished we would go to alky but that is not my call and my dad hates the stuff after we ran our last 2 motors on it, so we went back to gas. We run 110 Sunoco in the car also.

Doug Cool40 is right get the suspinion issue fixed the gear change will make for it leaving alittle more crazy with it hitting the suspinion with the gear change making it hit harder on take off.Rick has a 4.86 in the rx7 now 60 foot times at 1.26 to 1.24

Doug,

I don't know you but I can tell you about my gear problems. I also have a 466 A-429 heads on alcohol. I have been running a 488 gear and everyone told me to go to a lower gear. The best I had ever run at a local track was 6.31. I went to 430 and picked up 1.8 tenths. It ran 6.18 after getting it to hook right. The track was awful at first and came around about my 3rd pass. It ran 6.18, 6.19 and then 6.21 in first round, lost 60' time again. I took it to the Bash and ran a best of 6.24 in the heat.

In my personal opinion the higher gear will not help that much. Charlie is working on my heads as we speak and I should pick up a bunch. My intention is then to get a professional to get my chassis figured out. My car, 2388 lbs., will not sixty foot. Best 60' with the 430 is 1.39... sucks for this light of car huh. I have a feeling the engine is pretty close to where it needs to be but the chassis is way off. It sounds like we have similar problems.

Good luck Doug
Kerry

The first thought with a crooked right/left launch is usually a side-to-side preload problem. But the car's rolling burnout looked so damn straight that I'm not sure it's preload. While the video is a little lacking in quality, it appears to me that you staged a little too far to the left out of the center of the groove. That is one possible cause of the right launch if the left slick grabbed better than the right. It could have also just been crappy track/lane prep. Did it also try to drive right at the finish line too, or was it going straight down track?

The rear suspension reaction does look a little confusing because on one hand there was quite a decent amount of initial separation hit smacking the sidewall down into the track surface which makes the suspension look on the loose/violent side. But after the initial hit the car kinda looked like it was bouncing on the sidewalls more than bouncing on the springs making it look like the suspension was stiffer than shit (or possibly like it was ridding collapsed on the shock snubbers). But again it's hard to tell with the video quality.

I could also swear that I see sparks (or something glowing) just under the back bumper of the car as it leaves.


Where is the I/C sitting at, what brand shocks, how tight/loose are the shock's extension & compression valving set, what weight springs?

IMO.I think you are screwing up w/going to a 4.86 gear. The gearing is not your problem. The 4.30 should be perfect for that car.Like Jon said we need more info,like what CR,Cam,Timing,etc.

thanks guys for all the comments. The car weighs 2750 with me or my dad in it 200 pounds. The timing is at 28 right now, we set it right after we put the motor back together and it has not been touched so far, as most of you have said we think there are some suspension problems that we really need to get worked out to get this thing running the best that it can. Car seems to be running great after it gets past the .60 ft and everything right around 100ft it seems to be straight for the rest of the run, the last pass was the one that I was able to get on the video was by far the best with it leaving straight, the other 3 passes before it just would head straight to the wall and than he would have to bring her back to the tracks and than she would run. I really wished we could get the car scaled out and than make sure she is straight, I do think the lowering the laugh RPM to 4400 did help compared to the 4800 the other 3 runs were at. Also the cam is 726 726 @ .020 .304 intake .312 exhaust @ .050 it is .268 intake .276 exhaust with centerline 108.0.

Thanks,
Doug