EXsoccer1921

iTrader: (14)

i'm gonna need a 26x10 minimum. powell is working up a quote on me for a hub swap so hopefully i can get a 15x8/9 on there and run an 11" tread. it seems like a lot of tire but when i get my built trans and start launching off the 2step at around 15psi(upper 300's) i'm gonna need all the tire i can get. right now while i'm on my 16's i'm gonna get a 26x11.5 MT ET Street. 9.7" tread width and 10.8 section so idk why they say 11.5. but its still not a full slick so once i get the hub swap and the wheels i'll run a;
26x10 hoosier, 10" tread
26x10 m/h, 10" but smaller section width than the hoosier
26x10 MT, 9.6" tread

just all about how each one hooks.

i'd rather have the 3.82 drive on a built trans so i can stay in the power band longer but i guess the 3.82 still breaks. only the 4.45 is strong enough, i'll have to shift into 4th for sure but the power i'm making plus the 4.45 itself i'll still pull like crazy.

newt

iTrader: (2)

Sweet!

No love for the top 10 overall 1/4 spot? LOL

I snagged the 10th spot!

cmiller8006

iTrader: (3)

The 3.82 still puts all that stress on third gear where the trannies are breaking. There not breaking the diffs, at least if you have the lsd, Matt M did break the open diff in his lnf tho.

EXsoccer1921

iTrader: (14)

you'll need to be an hhr, cobalt, or g5

EXsoccer1921

iTrader: (14)

yeah thats why i'm gonna have to go with the 4.45


hell maybe i'll spray a 100shot in 4th. bring it up close to 700 haha

cmiller8006

iTrader: (3)

If your going to spray it, why not lol. But you know your car can do more than that if you turn the boost up. I know I am looking to do 550 or so and I will be happy.

EXsoccer1921

iTrader: (14)

yeah right now my injectors are static at 30psi. need to go with 198s and a couple more pumps

newt

iTrader: (2)

Huh fair enough I guess

slowswap

Shorter the gearing the faster you'll be. 4.45 will always be faster through the quarter then the 3.82.

EXsoccer1921

iTrader: (14)

maybe, maybe not. 3.82 would allow me to shift less and stay in boost/500+whp a **** ton longer. 4.45 while accelerating quicker, will also cause me to shift more and spool the turbo up one extra time. it could turn out that i'm shifting into 4th right at the wrong spot and as soon as the turbo spools back up i'm crossing the stripe so all i'm doing in 4th is shifting then waiting. while if i were in 3rd i'd be accelerating the whole time. but honestly i really dgaf if im running 4.45s, as long as its consistent.

slowswap

Let's make some assumptions so you can see.

Assumptions:

Trap Speed: 120
Tire size: 24.5

RPM per gear with 3.82
3rd - 7418
4th - 5595

RPM per gear with 4.45
3rd - 8642
4th - 6518

That's roughly 1000 RPM difference in each gear. Give me the shorter final drive any day of the week. Now if you know your tire size and estimated trap speed, we can pin point what would be the best option.

slowswap

I included a link to small spreadsheet I made to help calculate ideal tire heights and such. I included tire growth in the formula to account for it, although it might be a bit on the excessive side.

Hope this helps.

cobalt tranny gear calc.xls

slowswap

You want the ultimate setup, the quaife 6 speed, with the 3.82 final drive, will really help in drag racing because the 1-2 shift will be much more in the power band and easier to accelerate through.

cobalt tranny gear calc 6sp.xls

For ***** and giggles, with an 8000 redline, you'd be good for 150 in 4th on a 24.5. How ideal is that?! Such a perfect fit. 600 whp range and you'll be close to that trap, with some weight reduction of course.

------------------------------------

Sorry for multiple posts, but I really love gear ratios and how they effect acceleration.

mtbrent

Weight of car is why that honda is cutting those numbers. Will be tough, imo, to ever see those 60' in a balt without serious wr.

EXsoccer1921

iTrader: (14)

its already been done

not a big fan of downloads lol. but i do have an 8100rpm redline. trap speeds will be 125-135

mtbrent

The wr or the 60ft times? If wr, what are ya down to?

EXsoccer1921

iTrader: (14)

60' times. not by me though. iirc ryan has pulled some 1.5s and 1.6s on some of his passes from what we were talking about last time i was at the shop. weight reduction i don't have anything right now other than removing the entire interior save for the dashboard. running a turndown off the dp so no catback. hvac delete(weight of compressor, condenser, lines), no front bumper support. electric water pump(way lighter than factory pump and less lines) and no balance shafts. and i'm talking to five star bodies right now about a removable fiberglass front clip assembly that maintains factory body dimensions. not extended out like the profwd cars.

Hockeyman

iTrader: (4)

You can add me to the LSJ list if you want, although it's not that great of a run. Listen to those Nexen tires beg for mercy!
http://www.youtube.com/embed/c9tCUxpNOZY
2.8/60/i/e/rm/he/t/baldasstires 13.88@102 with a 2.35 60ft

EXsoccer1921

iTrader: (14)

concrete palace??? how was it?

EXsoccer1921

iTrader: (14)

whats rm?

slowswap

That makes no sense. Why remove weight off the front end? Other front wheel drives battle to add weight to the front end. The rear trailing arm could stand to be redone to remove weight from the back of the car. Coilovers will also help with extremely stiff rear spring rates.

Another thing to consider would be going to a smaller front brake kit to fit smaller wheels. Are 4 lug brakes smaller? Just something to consider.

You won't get a cobalt going fast until you get rid of that nasty 1-2 gear progression. I wouldn't be surprised if you could shave .5-1 second off of et. Not only is progression is bad, but first is also stupid short.

If you're building a whole transmission, might want to look at ways to change to better ratios.

07cobaltguy

Going wednsday to see what the 2.2 turbo can do with 15psi and corn.

EXsoccer1921

iTrader: (14)

i'm not worried about taking weight off the front end, weight is coming off everywhere. already have coilovers plus drag bags.

yes John is working on a 5 lug/ls disc brake setup for me with different hubs and knuckles and tc axles while maintaining ABS. so i'll be able to run a 14" wheel. just doing a 4 lug swap wouldn't be safe with the force being applied to the lugs, that and the axles would just suck *****.

4.45 built trans on a single stage limiter at about 12psi off the line and a nice slick. i won't spin so i'll be able to shift right at 8k and put me right in the 2nd gear powerband. nls'ing i won't have to worry about lag.

don't worry, this car has big things in its future lol

cmiller8006

iTrader: (3)

Exsoccer what you wanna do is great, but your car can go very fast without all the things you just mentioned and a 14 inch wheel. It will be neat to see what you come up with, but I will be staying with the lsj brakes and 15 inch wheels and 24.5 m and h tires. I too will be launching at 5500 minumum and about 10 psi in first, we will have to compaire our 330 foot marks to see who is getting out of the hole better. I know top end you should kill me tho. I have already ran a 5.02 330 and a 7.6 1/8th on the stock turbo and the same set up I mentioned.

EXsoccer1921

iTrader: (14)

yeah hopefully i'll have atleast a 30mph backhalf. launching will definitely take some practice. don't expect a video of my first pass

and the reason for the 14" wheel is since these cars just suck all around. instead of going taller tire, i'm just going smaller wheel and getting more sidewall in that way. i may still stick with the 15's though, just depends. the spacers that i had made hubcentric to the centerlines i found out will also fit another 15" wheel with the same dimensions only both these wheels cost less than one centerline