[Bruce K]

I did some testing Sunday in my T/A and my friends '72 Camaro. We both have Gtec's, mine the older pro and his the newer one. We hooked them up and did some 0-60 runs. The newer one read about .3-.4 faster than the old one.

He found this industrial area with a new concrete 1/2 mile straight with no buildings or traffic yet.

Anyways I'll just give you numbers with the new one. This was really my first time driving the car since I put on SSM traction bars. What a difference, no wheel hop! We had a gallon jug of water and did an initial burn out.

My friend ran a 3.84 (his car ran 11.06 @ 125, 1.545 60', Skip, he wants to run ya). Then we got in the T/A, all runs with both guys 180 (me) & 230 lbs. My first run, lost traction and ran a 5.8 or so. Then I started to get the hang of it and launching at 3000 and eased off the clutch and into the gas 4.84. A couple more times and upping the rpm to 3400-3500 I ran a best 4.24 with virtually no wheel spin! Enough clutch wear for the day.

It was quite a rush at around 4000rpm, the clutch fully engaged, no slip and pulling really hard, a quick lift throttle shift to 2nd and 60mph.

My times getting closer to the Camaro, he had to do one final run to widen the gap between us. He did a nice burn out (tires smoking white), and dealt a crushing blow with a 3.54! He has some alot of wheel spin, but goes like heck.

All my pals and myself included say I need more gear. Some think 3.73-3.90-4.10. I've never had a car with over a 3.55 ('77 L82 Vette) and wonder if a 3.73 would be fine for around town and occasional 10-15 mile highway, or would it be miserable. I was holding out for a Tremec before making a gear change, but it looks like the TKO600 will have to wait.

What do you think the 3.73 would do to my 0-60 & 60' times?

(The bad guy below)

[BILTIT]

I used to run a 3.23's and switched to 3.73's. I never documented the change but you sure can feel it. I was running a 400 then and it really liked it. The 455 could really use the 3.23's better i think. I don't like the highway cruising at 3200rpm.

It should help the launch.

[Bruce K]

We used to cruise our boat motors at 3500 all day long.

[Bruce K]

What would it take to get my 60' down into the 1.6-1.7 range?

[BILTIT]

What are you running for tires, traction bars, clutch?

[Bruce K]

MT 275/50/15 drag radials on 8" snowflakes, Southside Machine traction bars, Centerforce dual friction

[Bruce K]

I switched intakes, RPM on right now, Holley 750, standard ST10 trans w/2.43 1st

[BILTIT]

hmmm, any wheelspin? What tire pressures? How much burnout? What are you launching/shifting at? Timing? Looks like you have a solid setup and should be able to run a 1.7 no problem. You would be running quick if you could get the 60' down. I would guess with a 1.7-60 you should run mid/high 11's.

[Bruce K]

I agree, the times posted I think were on 7 cylinders. Had a real bad miss all the way to the track and almost didn't run. I ran 119.9 mph on my Gtec pro a few weeks prior.

My goal is to get into the mid 11's, but from what I gather, the Borg Warner may give up the ghost if I really hook hard at launch. A gear would help the trans out. Do you think a 3.42 would be noticably different, or just a waste of time?

Check out my first post for launch tech I have used. I found it difficult to get a good burn out at the track. I couldn't stop the car long enough.

30 psi on the street Sunday, 30 and 15 psi at the track

[BILTIT]

Sorry about all the questions, i see now most are answered in first post. I think the 3.42 would be a waste as the 4-sp would really like a 3.73 for launching purposes (auto's need less gear as we have convertor multiplication to help us). Thats just my opinion, i don't have much exp. with 4-spd. I used to run a st-10 in mine with the 400 but swapped it out. I think mostly some tuning and launching practice will help.

I am not a fan of the highway driving with 3.73's and may put my 3.23's back in for awhile.

[Junkyard Dog]

I used to run a Camaro with a 3.73 and a 4 speed and it was great! I even ran it on the autobahn in Germany for two years and took it on a trip across the continental United States. I had never owned a car with an overdrive and I did not know any better. The rpm range of the engine (where it ran best) was about 3,500 to 7,000 rpm.

Then I got old, drove cars with overdrives and stayed away from old cars. I finally got a 66 GTO with 3.55 gears and a 4 speed, and it is great "around town" as you say, but miserable on the highway.

A lot of it is perception and how old you are!

It will definitely help with your launch, but when you accelerate to 55 mph, it will feel like you need to shift up one more gear (which is where the overdrive comes in).

[Billy177]

I went from 3.23's to 3.90's and have the tko600. I think my 0-60 got a lot slower cause the car does not get any traction anymore. I can punch it at 40mph in 2nd gear and the tires will break loose. they are 275/60/15's BFG Radial T/A's

[BILTIT]

The BFG radial T/A's are a big part of the problem, i know from experience. I used to run 295/50's and i spun through every gear! The MTDR's are a whole different animal. I get spin through 1/2 to 3/4 of first then they stick like glue (on the street)!! At the track=no spin!

[Bruce K]

Billy, How did your install go? Did you have to modify the trans tunnel and did you use a kit with the offset shifter?

I think a 3.23 with the 2.87 1st gear would be a nice combo for you, nearly the same as a 3.73 with a 2.43 1st gear of the BW.

If your Radial T/A's are more than a couple of years old, they get hard and don't hook well at all, especially with your current combo of 3.90 x 2.87.

Btw, how would you rate the Tremec?

[Bruce K]

Originally Posted by Junkyard Dog

I used to run a Camaro with a 3.73 and a 4 speed and it was great! I even ran it on the autobahn in Germany for two years and took it on a trip across the continental United States. I had never owned a car with an overdrive and I did not know any better. The rpm range of the engine (where it ran best) was about 3,500 to 7,000 rpm.

Then I got old, drove cars with overdrives and stayed away from old cars. I finally got a 66 GTO with 3.55 gears and a 4 speed, and it is great "around town" as you say, but miserable on the highway.

A lot of it is perception and how old you are!

It will definitely help with your launch, but when you accelerate to 55 mph, it will feel like you need to shift up one more gear (which is where the overdrive comes in).

Your rpm range is a little higher than mine, so far only 6200 max. I'm getting a little old also,lol, but I only drive 8-10 miles usually on surface streets 50mph max to meet my car guys on Woodward. Occasionally I take the freeway home about 10 - 12 miles or so.

[Bruce K]

Originally Posted by BILTIT

Sorry about all the questions, i see now most are answered in first post. I think the 3.42 would be a waste as the 4-sp would really like a 3.73 for launching purposes (auto's need less gear as we have convertor multiplication to help us). Thats just my opinion, i don't have much exp. with 4-spd. I used to run a st-10 in mine with the 400 but swapped it out. I think mostly some tuning and launching practice will help.

I am not a fan of the highway driving with 3.73's and may put my 3.23's back in for awhile.

Even a 3.23 is no picnic on the highway. I'm trying to locate a set of 3.73's and give em a try. Eventually I think I'll get an overdrive.

[BILTIT]

Bruce, what tires are you running? Tires will change 60's drastically.

I used to launch my 400 at 5000rpm an it would annihilate the tires but i was young and thought it was cool, track time has shown me otherwise.


What do you mean by ''could not stop the car long enough''? I assume it wanted to push the front tires on you? When doing a burnout with a 4-sp you need to get tire speed up as quick as possible and that means ripping through first and into second very quickly (or skip first all together) without much car movement, this will get the tires up to a speed which will heat them up nicely (could use a line loc to help out).

[Bruce K]

I'm running the MT 275/50/15 Drag Radials. Maybe I was a little timid while doing my burnout. I guess I didn't want to burn out my rear brakes. The car started to move forward and when I applied the brakes it started to bring the engine speed down and I didn't want to mash the throttle and brakes at the same time, I never really got them smoking.

[Billy177]

the tremec install went well it only took about 3 hours and that is including replacing the clutch disk to a 26 spline. The only hard part was aliging the bellhousing. The transmission is excelent the shifts are smooth. I did modify the trans tunnel and I have the offset shifter however the shifter is not installed as the one they sent me was defective and I wanted to drive it, I still have to install the new offset shifter and the console. The overdrive(.64) is nice keeps the rpms low when crusing but with the torque of a 455 it pulls very hard on the highway all the way up to 160mph (4800 rpm)

as far as the tires go they are 2 years old with about 15000 miles on them. I know they are not the greatest as when they do spin they don't leave smoke or strips but that may be cause its been cold, around 45 degreese. I just dont want to go too sticky as I still have the 8.2 rear but with a mini spool

I highly reccomend the tremec it was the best thing i have done to my car

[BILTIT]

Originally Posted by Bruce K

I'm running the MT 275/50/15 Drag Radials. Maybe I was a little timid while doing my burnout. I guess I didn't want to burn out my rear brakes. The car started to move forward and when I applied the brakes it started to bring the engine speed down and I didn't want to mash the throttle and brakes at the same time, I never really got them smoking.

Some have said that a drag radial sidewall is too stiff for sticks, they are shocked too much and spin. You may have to run a softer sidewall to absorb some of the shock and get better 60's. You could try airing down to 12-13psi, might help.