I have a 1996 Gt non PI, 5spd. I have 4.10 gears, off road x-pipe, catback, plugs and wires, fenderwall intake, short shifter, hardened tranny and engine mounts, King Cobra clutch, lowering springs, and I have 18inch saleens replicas with 285/ 40/18 Sumitomo street tires, and a different thermostat but im not sure which one because it was on there when I bought it. I went to the track in the begining of the year actuallt opening day with my stock 17 inch rims with 275 street tires. I did horrible, my best 60 foot was like a 2.6 and I didnt get traction till third, it didnt help that it was drissling but im not trying to make any excuses. I had a few really good reaction times. My best 1/4 miles was a 15.1 at 96mph. So tonight me and my buddies went back to the track it was really humid and about 85 degrees out, but the track was hooking pretty nice. I had decent reaction time I think my best was like a .343 and my best 60 foot was a 2.174 which I think is decent for street tires. But my best 1/4 miles was 15.132 And the best mph I saw all night was 94mph but I averaged about 92mph So heres the thing my car was hot all night I even let it sit with the hood up for a half hour and the lowest it got was half way, then I got in the car and turned the heat all the way up and drove slow to staging maybe 1/4 a mile and my car would get to 3/4 heated up So the only thing I can think is to do a tune up and check the timing? but it had a proffesional tune up about 3000 miles ago. So this is what im wondering is the heat part what is slowing me down that much or is it also that I added 18inch rims with bigger tires so theres more rotational mass? Im confused I thought I would have went low 14's especially with my 60"? I have MT ET streets on 15inch welds that im just waiting on the lug nuts to come in the mail. I figure this should help out alot. Is there anything else anyone can think of to check or to help me out? Sorry for the long post.
Alot of things are hurting your 60' times. Lowering springs reduce weight transfer to the rear, the 18" rims are more than likely heavier than your stock rims (remember 10lbs of rotational mass = about a tenth), Sumitomo tires aren't great for traction, and the 4.10s are making you spin even more. If you want to lower your times than you need to change the above things. I would also suggest boltons that help your upper rpms especially for non-pi's. Like cams, PI intake, etc since the 4.10s keep your engine at higher rpms. Consider upgrading rear end parts like axles if you plan to launch hard on the et streets.
The 18" rims and the excessive heat probably had alot to do with you mph being down from your previous runs. Put the sticky tires on and wait for cooler weather and you'll get into the 14's easy.
On your timeslips does it show a weather station including corrected altitude. Every day is different with regards to weather. It really affects your times. Your rims, street tires, suspension all hurt your times let alone being non-PI. Your going to have to do some power mods to get you some 13 second timeslips. Drag radials are a must and a good start.
No doubt that the heat coupled with the heavier tire/rim combo hurt your times. You don't have a lot of mods on there that would help your times. An inexpensive upgrade consisting of PI cams with a PI intake really wakes up the upper rpms of these cars and makes a lot of headway in reducing the 1/4mile times. Good luck with your next runs.
heres what I recommend...sell it...buy a 96-98 cobra or swap a pi engine in it I trapped 98 in my auto 96 gt on a hot humid day.... corrected time slip for me was 13.8 at 100 with the mods in my sig your gonna need to do some more work if you want to get close to 13s long tubes pi cams intake and tune should get you close.
Just running when the air temperature is cooler and low humidity will drop your times .2 to .3. Are you running during the day or at night? The 245-45-17 tire on my '00 GT are 25.68 inches in diameter your 285-40-18 are 26.98 inches in diameter that is like losing 1 gear size you would need a 4.30:1 with these tires to be the same as a 4.10:1 with the 17's
I drove it today only for like 10 miles and the temperature gauge read 3/4 so I think something is wrong because I wasnt beating on it or anything. It feels really low on power too. My buddy and I are going to try and figure it out, We are going to try new high performance plugs and a new thermostat anything else anyone can think of?
Have you figured out what * thermostat you have yet? Atleast put in a 180 and that'll likely help a bit. Do you have a programmer? If so, go and set your fan temps lower so they'll kick on quicker. Even in this Texas heat, I usually run 178-182 coolant temp wise, which is quite a bit better than the 200-210 that I was running
Upgrade your cooling system =] Mine overheat so i have to blast the heat on full on 95 Degree day just to get her back down to safe temps and it sucks lol. Im thinking my water pump is going out. But check your cooling system if its gets hotter than it suppose to. also burp your coolant system to make sure you dont have any air bubbles.
It had a recent tune up probably about 5k miles ago but it has probably been about three years since I dont drive it much at all. I am going to try simple things like spark plugs, thermostat, and oil change. Also maybe I could have got some bad gas? What thermostat should I get?
I went back out tonight and I did a little better. My best was r/t: .199 60"- 2.128 1/4- 14.895 mph: 93.71 I did have a run were I trapped 96.02, but I had a 2.2 60" and somehow ran 15.015 The car still heated up a little too much so im going to mess around with it a little and im hoping once my lug nuts come in and I can use my new tires I will be able to get down into the low 14's
At the moment, I don't see it happening. If I were you, I'd work on fixing your problem before you go and put on sticky tires and take the chance to break something else. You are already cutting decent 60's and likely won't cut too much time off of the 60' to say the least. What was the temperature like?
Tonight wasnt bad. It was probably around 80 degrees out maybe lower but not too humid. The other night I dont think it dropped below 85 degrees and it was very humid.
Can you list all your mods? You still have the factory t-stat? Get that cooling problem fixed before you run into more problems
No its not the factory t-stat, but im going to switch it out again just incase some how it got messed up. But my head hasnt been in the right place this week and I guess I accidently put in 87 octane, my friend told me I usually run 93 so maybe I fouled a spark plug? All my mods are in my first post.
Take the thermostat out and look at it and find out which it is. If you don't see the number visible on the exterior of it, get a light source and view in the "hole" and it'll tell you. I'm sure that doesn't make sense while reading it, but once you get the thermostat in hand, you'll understand With the weather and such, I don't think your times are really all that much off. You have gears and exhaust, though also have the heavier rims which are hurting a bit. Have you corrected the times?
