Regear or up boost question
#1
Regear or up boost question
In the land of theory here, so bear with me.
Car is mechanically limited via gearing and cam to roughly 143mph. 6400 shift, 3.73s, and 28s. pt76gts turbo, 10-12psi area
Question arises on whats easier; add boost in quicker and try to ET quicker, or re-gear for a better ET?
Again in theory, a shallower gear set, 3.54 area should build boost much faster. But, if I do toss 3.54s in, and the turbo runs out of steam, its all for nothing and I waste a lot of money.
Thoughts?
Car is mechanically limited via gearing and cam to roughly 143mph. 6400 shift, 3.73s, and 28s. pt76gts turbo, 10-12psi area
Question arises on whats easier; add boost in quicker and try to ET quicker, or re-gear for a better ET?
Again in theory, a shallower gear set, 3.54 area should build boost much faster. But, if I do toss 3.54s in, and the turbo runs out of steam, its all for nothing and I waste a lot of money.
Thoughts?
#2
Pull some gear out of it. Turbos need to be able to lean on somthin. With my experience in turbo hayabusas the less the gear the better. I've never had to say it needs more gear.
#3
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this is true I changed from a 3.42 to a 4.00 gear in my buick when I went to a 9" axle and the car slowed down half a second. I had a 3.00 gear so I put it in for street driving and it felt so good I ran it at the track and it was .3 faster than my best with a 3.42. never changed it. the strange thing is the 3.00 gear was the fastest 60' as well.
#12
this is true I changed from a 3.42 to a 4.00 gear in my buick when I went to a 9" axle and the car slowed down half a second. I had a 3.00 gear so I put it in for street driving and it felt so good I ran it at the track and it was .3 faster than my best with a 3.42. never changed it. the strange thing is the 3.00 gear was the fastest 60' as well.
#17
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Matt if you wanna keep the S60 throw the 3.54s in it. I can only see it going faster. I don't think the gear swap alone will hurt the efficiency of the turbo more than it already is. If you wanna go through the trouble of pulling that rear back out and selling it, get a 9in with 3.23s
#18
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I have a little 302cid 4.8 and 3.25 gears in my 9" going 142mph in the 1/4 on low 14psi boost.. and it cruises down the highway at 2800 going 76 mph with 28" tires..
people have always told me you can never have to much gear just not enough power to pull it..
people have always told me you can never have to much gear just not enough power to pull it..
#19
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FWIW I had 3.25s in my 6 speed car last year, which most consider way too low. Car had absolutely no issues getting through the power band and my butt dyno tells me its faster because . The only issue was that 6th gear was useless untill about 90mph haha.
I put 3.50s back in this year but i threw on 28" tires so its still the same final drive as having 3.25s, i love it.
I put 3.50s back in this year but i threw on 28" tires so its still the same final drive as having 3.25s, i love it.
Last edited by Ryans99ls1; 07-22-2014 at 08:03 AM.