thank you very much.

 

like this.I just got a 5.3 in my 3600 car with me in it and hoping for 9s with it

 

You are going to want to run something like a 3:55 gear out back.... as those 4:11's are going to be too short and you will be shifting too fast.

I run a 3.31 gear and 26" tall tire.... while it is long in each gear... once you make boost it feels great. It just pulls and pulls and pulls. Turbos like load.... superchargers need gearing.

 

Is that with a larger motor? What kind of shift point? I was under the impression with the smaller cubes you wanted to gear them shorter and rev them out more. Esp if you are heavy or aren't making 1400 crank... Evry time I went down in gear size I picked up with my 5.3/4.8 combos. Started at a 3.10 AND 30" tire... Then a 3.50... then a 3.64 and a 28". Picked up quite a bit each change and I still dont' think I had enough gear. This was in a relatively light weight setup as well at about 3000lbs pulling 7300 or so through the traps at 158ish. Still saw 1100+ rpm drops at the shift with a 17 stator ptc. Felt like a 3.73 or so with a 28" and an 18 stator would have been perfect for that combo. If I Were at 3600lbs I'd think the mechanical advantage of the gear would be even more important.

 

First and second are kinda useles.

 

At 700whp on a street tire, 3rd is hit or miss and any bump on 4th also caused a loss of traction for me.
Made my butt hole pucker more than once for sure lol.
My 275/50/15 MT Street R's were magic on the street though.

 

Whats my problem lol

 

Self own.

 

I have twin gt35s with same size as you. 5.3 motor with 4.08s made 702 on 18psi. The 4.08s were useless. Went to 3.37 and loved it. Then I went th400 and swapped to 3.54, cars now a t56 magnum and getting couple more psi on the tune soon.

3450 weight for my car. So we pretty identical. Do waste a minute of your time with the 4.08s. Also my car has the btr stage 2 turbo cam. Works fine. My dyno graphs looks exactly like there comparison charts. Tq drops off around 6000ish and hp Meets there and climbs.

 

i still have the 3:55’s I took out. I will put them back. God I want this car done. Still debating on the stage two or three cam. Stage two would be plenty for this little car. But summit guy was saying lean towards the three.

 

The gear ratios in the manual are what make the shorter gears harder to plant. A 2.66 first gear is pretty nutty, you need really good suspension and tires to plant that, but guys do it all the time. With a heavier car I'd still think a shorter gear is the way to go. I'd try the 4.11's personally first.

The starting line ratio seems better in 2nd gear. Starting in 2nd with a 4.56 is the same as starting in 1st with a 3.08. Should be much more manageable, but you can't "drop" the clutch and go.

*IF* you have the rpm on tap for your power level, a shorter gear will defiantly be better in a heaver car. To say a short gear is unusable isn't exactly true. Tune the setup around the gear and trans and sort he the suspension out to handle the shorter gear. You'd be much better off IMO.

At 3450 and 700hp you should be trapping 135-140. I'd gear the car for 140 at your redline/tire size... what ever that gear may be.

A 26" tire and 7k would put you at 153 with the 3.55. 132mph with a 4.11
Rev it to 7400 and you'd be at 139 with the 4.11. About perfect IMO.

The clutch slipper valves make for pretty exact repeatable launches VS just trying to do it manually. There are a few different types, but if I were doing any racing with a manual trans from a stop, I'd want something like this.

https://www.grannasracing.com/produc...solenoid-valve

 

Alright. Better to error on the side of caution and go with 2. You can always apply more boost but if you get stuck with a lazy combinations...that's hard to fix. Go with 8706 and don't look back.

 

thank you very much.