Why did the L98 not come with 3.45's?
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Why did the L98 not come with 3.45's?
Now I know the reason that their was never an L98 5-speed was because the trans at the time couldnt hangle the torque of the 350. BUT why was there never a 350 that came stock with 3.45 gears? Why put 2.77's in a performance car? The 89 iroc z L98 ran a 14.8 stock. If it had 3.45's stock it would probably have hit 14.4's.
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Re: Why did the L98 not come with 3.45's?
they had 2.77's and 3.27's. I think the reason was for gas mileage purposes and the simple fact that a L98 fbody with the 3.45's would rival the Vette's of the same years in performance. GM couldnt have that. Else L98s would be very close to breaking 13's bone stock
p.s nice avatar
p.s nice avatar
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Re: Why did the L98 not come with 3.45's?
Don't forget 'emissions per mile'....my car went 14.3x with just a set of 3.73:1s. -Bill
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Re: Why did the L98 not come with 3.45's?
they had 2.77's and 3.27's. I think the reason was for gas mileage purposes and the simple fact that a L98 fbody with the 3.45's would rival the Vette's of the same years in performance. GM couldnt have that. Else L98s would be very close to breaking 13's bone stock
p.s nice avatar
p.s nice avatar

Yeah I think the G92 cars got 3.27's. Still 3.27's isnt a while lot better than 2.77's on a TPI car. I have also heard from others [now yourself] that it was because the Corvette of 1989 ran low 14's, which is where 3.45's should put a stock L98 car.
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Last edited by 89IrocZ350TPI; Apr 8, 2008 at 06:57 PM. Reason: Automerged Doublepost
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Re: Why did the L98 not come with 3.45's?
gas mileage. I don't buy that the 3.45s would have put it too close to the Corvette at all-----hardly a difference between 3.27 and 3.45s (Camaros still heavier and auto only)
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Car: 89 Iroc-z
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Re: Why did the L98 not come with 3.45's?
yeah i did the 2.77 to 3.27 swap and although the car felt faster from rolling starts and such, i only was able to match my best ET on street tires and 2800 stall. I did pick up a mph or 2 on average from the swap. 96.6 to 98 or so. With a set of slicks i'm sure 3.27's were worth a tenth to a tenth and a half. But the 3.42's i have now in the 10 bolt, it felt like it picked up alot. Just still hard to launch on street tires with more and more gear.
the difference for me between the 3.42 and 3.27 was more than the 3.27 and 2.77's
the difference for me between the 3.42 and 3.27 was more than the 3.27 and 2.77's
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Re: Why did the L98 not come with 3.45's?
3.4X gears are probably the best all around for TPI. You should try 3.73's now that you have an HSR setup..
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From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: Why did the L98 not come with 3.45's?
3.70/3.73's would be perfect for 1/4 mile times with HSR on a L98. Even most head/cam setups will like it alot.
I now have a 383 HSR that wants to rev up alittle, so i need to get me some 3.73's or in a perfect world, 3.90s to get my car to run its best. I will hold on to the 3.42's for the time being
I now have a 383 HSR that wants to rev up alittle, so i need to get me some 3.73's or in a perfect world, 3.90s to get my car to run its best. I will hold on to the 3.42's for the time being
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Car: '91 Z28 L98 G92
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Re: Why did the L98 not come with 3.45's?
Stock G92 option on my '91 Z28 5.7 Auto was 3.23:1 axle ratio. Spin the tires off of the car with 3.73s?..........does "Burnout91" give you hint? It spun bad with the 3.23s too...!-Bill
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Re: Why did the L98 not come with 3.45's?
Hey I just read your profile and I was wonder what is your rwh? I cant see the graph its too small, and also what do your 1/4 times look like?
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Re: Why did the L98 not come with 3.45's?
Bill
P.S.: If you look for a thread in the So Cal forum titled "ThirdGen Dyno Day", the dyno graph is also posted there.
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Re: Why did the L98 not come with 3.45's?
Cool. I have a similar setup as yours, and I am currently looking for a good head/cam match. I want to have around 300wrh and run mid 12's. Pretty much where you are at.
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