Updated: 1st Run In 86 Gt, Low Mph (in My Opinion) Any Ideas?

First things first... Throw out everything that you are thinking and get the car to 60' first. The rest of the data is completely irrelevant until the car hooks
second run was a little better, not as much wheel spin, ran a 14.3 at 93.96
this needs to read " there was no wheel spin" and then we will have a place to start
 
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First things first... Throw out everything that you are thinking and get the car to 60' first. The rest of the data is completely irrelevant until the car hooks
this needs to read " there was no wheel spin" and then we will have a place to start

ahem... read my earlier post about 60ft times, tire pressure, launches, real rear tires.. just sayin
 
You know I was sitting here thinking the same thing my 87 gt convertible stock long block speed density stock air box all it had was shorty headers,off road H-pipe, cat back the car was an AOD shift kit mild stall with 3.55s on street tires ran 14.0 at 95 mph...I'm sure on drag radials I would have hit high 13s...so I'm thinking now something is off MPH is a little low...
 
Whats your altitude and DA? My car when na was similar to yours t moss ported cobra, gt40 heads, tfs stage 1 cam, 70 mm throttle body, 90mm LMAF, full exhaust, tko 600, 3.73s, tuned via quarterhorse. Ran consistently around 14.7@ 94 but my altitude is 5500ft with DA's hovering btw 7000 to 9000ft.
^^^ this makes a huge difference and is an excellent question.
 
I'm going to bump the timing up and try different shift points next time out to see if it makes a difference. The tach actually seems pretty close when compared to the readings on the digital timing light. It might be off too though.


Thanks for the ideas guys, keep em coming.
Stock tach is way off, I have a Stewart Warner digital tach set for 5100... When the light comes on the stocker is reading5600-5700 prob, if not higher. You wanna prob shift earlier, power goes flat at 5k on this setup


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Well, Just got home from the track, timing and a little cooler air made a big difference.

I bumped the timing to ~17* and shifted at 5600, temp was 65-70* at the time of the runs

First run: [email protected]

Second run: [email protected]


Still spun bad, the second run spun a little worse and I was asleep at the light.

60 fts were 2.124 and 2.294

I know the cooler air helped, but it seems that low timing was the bulk of the problem. Thanks for the tips and advice, now it's time for some tires and to finally put those MM subframe connectors on.

I'm just glad the MPH is closer to where it should be. Now I can start working on ET
 
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Well, Just got home from the track, timing and a little cooler air made a big difference.

I bumped the timing to ~17* and shifted at 5600, temp was 65-70* at the time of the runs

First run: [email protected]

Second run: [email protected]


Still spun bad, the second run spun a little worse and I was asleep at the light.

60 fts were 2.124 and 2.294

I know the cooler air helped, but it seems that low timing was the bulk of the problem. Thanks for the tips and advice, now it's time for some tires and to finally put those MM subframe connectors on.

I'm just glad the MPH is closer to where it should be. Now I can start working on ET


Just to clarify, on the second run, you can sleep at the light all day but your time doesn't start until you break the beam. Treeing the light only matters when someone is beside you.

So you can take your time for future reference unless you want to also beat the guy beside you (if there is one).
 
Just to clarify, on the second run, you can sleep at the light all day but your time doesn't start until you break the beam. Treeing the light only matters when someone is beside you.

So you can take your time for future reference unless you want to also beat the guy beside you (if there is one).

I'm aware of that, it was just a comment on the run, not in reference to the et or mph.:nice:
 
You'd probably pick up some mph with a better MAF/24#inj and maybe the fuel pump. The reason I say this is some of the cars I've seen that weren't getting enough fuel didn't throw any signs of being lean. The power band just was flat in the last 1500rpms. You've got to be close to the limits of 19#inj with your combo. Obviously et would improve a lot with suspension/tires and more seat time. I re read your mods. I initially thought you had stock heads. With those mods you should/could be around 102-105mph(with the proper additions I stated already). For a frame of reference for every .1 you take off the 60ft time usually equates to about .2 in et reduction. So a low 13 is very likely in the future. Good luck