4.30 gears, lower ET how much?
10-27-08, 12:59 PM
#26
At the end of last year, with the stock 4.10 gears and 24.9" Hoosier drag radials, my best run was a 11.19 ET @ 123.80 with a 1.61 60 ft. 7.19 1/8th mile @ 97.13.
This year I got 4.77 gears and 26" MT ET Streets. With the taller tires, it makes my final drive ratio 4.57 (Its like having 24.9" tires with 4.57 gears in the rearend). I also added a roll bar that weighs 55 lbs, and I removed 170 lbs of stuff like everything out of the interior, ABS, the greddy catback and some other stuff. Before I removed the 170lbs, I was running 11.5s all year and my best was 11.40 last week. After I just removed the 170 lbs, my best is now 11.16 @ 122.25 with a 1.53 60ft! 7.12 1/8th @ 94.54.
So I think the 4.77 gears hurt my 1/4 mile times. My time to the 1/8 mile is .07 quicker, but my time from the 1/8th to the 1/4 mile time is actually slower by .04 secs, and I didn't beat my best trap speed which I got with the 4.10s.
And I can also contribute the better 60ft times to mostly my driving, the 170lb weight loss and the tires. Last year my best was a 1.57 60ft with the Hoosiers, and all year I didn't beat that (I matched it once) until this last week after I removed the 170lbs. I did a 1.56 and a 1.55 with the tires spinning some and had to shift into 2nd right before the 60 ft mark, and my last run I did a longer burnout and I noticed I got better traction and pulled a 1.53 60 ft and didn't need to shift until right after the 60ft.
So now I am wondering if I should put the 4.10s back in. But then my gearing will be like 3.93 because of the bigger 26" MT ET streets, and that may hurt my times. It sucks cause I spent so much money on the 4.77s with all new bearings and the install and they didn't help my times. It seems the 4.30 gears would maybe work best, then my final drive ratio would be like 4.12, which is like that same as last year when I got my best trap speed and that's when my car was 115 lbs heavier.
This year I got 4.77 gears and 26" MT ET Streets. With the taller tires, it makes my final drive ratio 4.57 (Its like having 24.9" tires with 4.57 gears in the rearend). I also added a roll bar that weighs 55 lbs, and I removed 170 lbs of stuff like everything out of the interior, ABS, the greddy catback and some other stuff. Before I removed the 170lbs, I was running 11.5s all year and my best was 11.40 last week. After I just removed the 170 lbs, my best is now 11.16 @ 122.25 with a 1.53 60ft! 7.12 1/8th @ 94.54.
So I think the 4.77 gears hurt my 1/4 mile times. My time to the 1/8 mile is .07 quicker, but my time from the 1/8th to the 1/4 mile time is actually slower by .04 secs, and I didn't beat my best trap speed which I got with the 4.10s.
And I can also contribute the better 60ft times to mostly my driving, the 170lb weight loss and the tires. Last year my best was a 1.57 60ft with the Hoosiers, and all year I didn't beat that (I matched it once) until this last week after I removed the 170lbs. I did a 1.56 and a 1.55 with the tires spinning some and had to shift into 2nd right before the 60 ft mark, and my last run I did a longer burnout and I noticed I got better traction and pulled a 1.53 60 ft and didn't need to shift until right after the 60ft.
So now I am wondering if I should put the 4.10s back in. But then my gearing will be like 3.93 because of the bigger 26" MT ET streets, and that may hurt my times. It sucks cause I spent so much money on the 4.77s with all new bearings and the install and they didn't help my times. It seems the 4.30 gears would maybe work best, then my final drive ratio would be like 4.12, which is like that same as last year when I got my best trap speed and that's when my car was 115 lbs heavier.
12-02-08, 12:17 PM
#28
Yes. The Hoosiers are nice cause they are the stock size, these are good to use unless you are making more than like 350 hp. I think I'm getting slightly better traction with the ETs. They are both good. But I haven't ran the MTs yet with the stock 4.10s and I'm hoping they don't slow down the car because they are a bigger diameter tire, I have only ran them with the 4.77 gears I had.
12-02-08, 02:30 PM
#31
tom,
1. reading this thread i was hoping you'd end up going with the 25" tire and 4.3 rear, as i thought a 4.7 rear would definitely be overkill. now that you've updated the thread, i see i was right! I'd go with the 4.3 rear and keep your 26" tires to get your final drive ratio back near stock. I think with that setup you should be able to drop atleast a tenth off of the ET, as 150lbs of weight reduction is a lot! I would think that dropping over a tenth of the 60' and dropping 100+lbs of weight would be enough to get you into the 10s.
2. also, not to **** on your parade here, but i hope you're not running this 20psi of boost on regular pumpgas, as 17-18psi is usually about the limit on a 9.0:1 compression motor like ours, the point at which 93 octane gasoline starts igniting itself. however, I'm glad to see your turbos have lasted this long running the higher boost. you definitely proved me wrong on that one
3. i have a question: do you have any trouble with your car getting unstable using the wrinkle walls in the rear and the the stock'ish tires in the front? i've always heard it's best to use some skinnies up front to balance out the "wobble" of the slicks in the rear, but i've never tried it myself. you seem to have made quite a few passes on that setup so i was just curious. great job running low 11's with your setup, you're definitely a badass for running that fast and trying different setups to push those stock twins.
1. reading this thread i was hoping you'd end up going with the 25" tire and 4.3 rear, as i thought a 4.7 rear would definitely be overkill. now that you've updated the thread, i see i was right! I'd go with the 4.3 rear and keep your 26" tires to get your final drive ratio back near stock. I think with that setup you should be able to drop atleast a tenth off of the ET, as 150lbs of weight reduction is a lot! I would think that dropping over a tenth of the 60' and dropping 100+lbs of weight would be enough to get you into the 10s.
2. also, not to **** on your parade here, but i hope you're not running this 20psi of boost on regular pumpgas, as 17-18psi is usually about the limit on a 9.0:1 compression motor like ours, the point at which 93 octane gasoline starts igniting itself. however, I'm glad to see your turbos have lasted this long running the higher boost. you definitely proved me wrong on that one
3. i have a question: do you have any trouble with your car getting unstable using the wrinkle walls in the rear and the the stock'ish tires in the front? i've always heard it's best to use some skinnies up front to balance out the "wobble" of the slicks in the rear, but i've never tried it myself. you seem to have made quite a few passes on that setup so i was just curious. great job running low 11's with your setup, you're definitely a badass for running that fast and trying different setups to push those stock twins.
Last edited by jacobcartmill; 12-02-08 at 02:32 PM.
12-03-08, 12:00 AM
#32
I definately wish I would have bought the 4.30s to begin with instead of the 4.77s, they would be best for the 26" MT ETs, or just kept the 4.10s in. I decided to not spend anymore money (I already wasted enough) and just put the 4.10s back in and see how it does with that setup. The weight reduction did help alot!
Lately my turbos have been running at about 17-18 psi, occasional spikes higher, I really only seen 20 psi when it was very cold in the winter. I have always just used 93 octane pump gas. I will be putting on another set of non-seq twins and I'll see if they make more boost which will tell me if my current stock turbos have gotten warn out at all.
I have not had it get unstable or scary, and I drive to the track with the slicks and front motorcycle tires on the factory spare rims, and occasionally on the road when I still had those tires on the car. It's always been good on the track. Thanks.
Lately my turbos have been running at about 17-18 psi, occasional spikes higher, I really only seen 20 psi when it was very cold in the winter. I have always just used 93 octane pump gas. I will be putting on another set of non-seq twins and I'll see if they make more boost which will tell me if my current stock turbos have gotten warn out at all.
I have not had it get unstable or scary, and I drive to the track with the slicks and front motorcycle tires on the factory spare rims, and occasionally on the road when I still had those tires on the car. It's always been good on the track. Thanks.
01-06-09, 04:35 PM
#37
If you have high horsepower, I think 4.10s or 4.30s at the most are best with the 26 inch tire. So far my only experience with the larger tires is with the 4.77s which was too much gear. For my hp I think 430s would be best with the 26 inch tire, but I want to see how it goes with the stock gears first and didnt want to spend or possibly waste any more money on the gears. For more hp, 410s may be better.
05-25-10, 12:20 PM
#38
sorry to bump an old one.
would you mine listing the set-up you were using when you ran the low 11's SEQUENTIALLY? i see in your sig that you are full non seq now.
ill probably never go non-seq. and ive got almost full bolt ons, just waiting for injectors, hopefully soon. curious as to what you were running?
would you mine listing the set-up you were using when you ran the low 11's SEQUENTIALLY? i see in your sig that you are full non seq now.
ill probably never go non-seq. and ive got almost full bolt ons, just waiting for injectors, hopefully soon. curious as to what you were running?
06-03-10, 06:30 PM
#39
I had all the same mods when I did 11.16 sequentially, see mods list, except the car was heavier. after I went non-sequential I did alot of weight removal and ran a little faster but the clutch was slipping too, so it should have went faster, and I haven't been able to get any good runs in since then, got a rebuilt motor now too. Now I'll have to wait till a cool night or until the fall, it does alot better in the cold air.
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