TPI, T5, 3.42 swapped

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Welcome to the site from Houston. Cool car! I'm surprised you find the gearing to be tall. Are you sure its a 3.42? I really like this rpm calculator....

http://www.csgnetwork.com/multirpmcalc.html

Use the bottom section so you can plug in your overdrive ratio.

According to it, a 25.6" tall tire with a 3.42 rear gear and a .63 overdrive should turn 1838 RPM at 65 and around 2404 RPM at 85. That doesn't seem that tall to me which is why I ask if you are sure it is a 3.42. I don't doubt its an 8.5 but who knows if the gearset has been changed. Maybe a 3.08?

Is the identification tag still on the trans? If you can identify the transmission for certain (thereby identifying the gear ratios) and confirm the rear axle ratio (jack up rear end and see how many turns of the driveshaft = one turn of the rear wheel - will be close enough to tell if it is 3.42 or something else) that will help in identifying what change to make to get the car more to your liking.

The clutch desperately needs to be replaced. It wasn’t apparent immediately because I babied it the 200+ miles home from where I bought it. I cranked on it and did some drifting and donuts in a parking lot for my 8 year old son. That pretty much fried whatever was left of the clutch plate. Hahahaa. So maybe the bad clutch makes it seem geared tall. A new clutch kit is first on my list but it’ll be months before I’m able to get to it. I bet that’ll make all the difference. If not, maybe 4.10s is where I need to be. 👍🏽
 
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4.10s with a stock TPI 305 is not a good combo. I had a warmed-over TPI 305/WC T5/3.08 combo in my '91 Z28 and it was not doggy at all.

Case in point (heh... I was still a shitty driver 10 years ago):

3.42s are about as far as you want to go with 26" tall tires and that torquey low-reving engine. 3.73s if you up to a 27-28" tall tire and have plans for a 350+ down the line.

But, fix your clutch first so that you have all the torque being transferred to the drive wheels.

Buy this: http://www.moates.net/aldu1-and-cabl1-p-127.html?cPath=64
Download this: http://www.tunerpro.net/

...and figure out exactly what that car is doing with respect to its state of tune. You may have the wrong injectors or a fuel pressure issue (I see a gauge near the DS frame rail) - does it have an adjustable FPR? Vacuum leaks? Clogged/restricted intake/exhaust?
 
4.10s with a stock TPI 305 is not a good combo. I had a warmed-over TPI 305/WC T5/3.08 combo in my '91 Z28 and it was not doggy at all.

Case in point (heh... I was still a shitty driver 10 years ago):

3.42s are about as far as you want to go with 26" tall tires and that torquey low-reving engine. 3.73s if you up to a 27-28" tall tire and have plans for a 350+ down the line.

But, fix your clutch first so that you have all the torque being transferred to the drive wheels.

Buy this: http://www.moates.net/aldu1-and-cabl1-p-127.html?cPath=64
Download this: http://www.tunerpro.net/

...and figure out exactly what that car is doing with respect to its state of tune. You may have the wrong injectors or a fuel pressure issue (I see a gauge near the DS frame rail) - does it have an adjustable FPR? Vacuum leaks? Clogged/restricted intake/exhaust?

you made too many left turns, all your blinker fluid ended up on the right side.....🙂
 
you made too many left turns, all your blinker fluid ended up on the right side.....🙂

I never washed that car... so I sure as hell wasn't spending money on more blinker fluid.
 
4.10s with a stock TPI 305 is not a good combo. I had a warmed-over TPI 305/WC T5/3.08 combo in my '91 Z28 and it was not doggy at all.

Case in point (heh... I was still a shitty driver 10 years ago):

3.42s are about as far as you want to go with 26" tall tires and that torquey low-reving engine. 3.73s if you up to a 27-28" tall tire and have plans for a 350+ down the line.

But, fix your clutch first so that you have all the torque being transferred to the drive wheels.

Buy this: http://www.moates.net/aldu1-and-cabl1-p-127.html?cPath=64
Download this: http://www.tunerpro.net/

...and figure out exactly what that car is doing with respect to its state of tune. You may have the wrong injectors or a fuel pressure issue (I see a gauge near the DS frame rail) - does it have an adjustable FPR? Vacuum leaks? Clogged/restricted intake/exhaust?

Yeah, I’m hoping a new clutch makes all the difference. Supposedly, the motor has heads, springs, and a cam. Once the motor warms up, it doesn’t lope at all. It has a crazy lope when I first start it though. Lol. So I’m assuming there’s a fuel issue or vacuum leak. It runs well. It might just need a tune as well??? I think it may run rich too. Anyway, I just got it and haven’t gone through everything yet. It’s a project so I’ll get to things when I can. Thanks for the tips.
 
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If you have the stock shifter you shoudl upgrade to a brand that has stops. I have a Hurst shifter with stops so I can't overshift like you can with a stock floppy shifter. I drive my GP daily and I like the 3.08 rear end so I don't have to shift it every 30 feet in the city.

I'm not sure why you would need a shifter with stops on a T5. That's an internal rail shifter with stops already machined in the shift plate in the tail housing.
 
I'm not sure why you would need a shifter with stops on a T5. That's an internal rail shifter with stops already machined in the shift plate in the tail housing.

The difference with the Hurst shifter compared to the stock shifter was like night and day. There are complaints about the stock shifter on many forms. I know about the channels with the ball bearing which are supposed to control the shifts but the shifter is very sloppy

"
Truckedup said:
But 3rd gear,Camaro or Mustang,is the weak link.If you avoid full throttle shifts and teenage burnouts,it'll hold up ok behind a moderately built V-8.​

This is mainly due to a limitation of the stock shifter & the lack of shifter stops. The "overshifting" of the 3rd gear fork causes bending, cracks & excessive wear on the pads - this results in less than perfect meshing of the synchro & dogs. A shifter with positive stops, adjusted correctly, will minimize this inherent weakness."
 
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The slop in the shifter is in the shifter "tower" itself. If you remove the shifter and actuate the trans with a rod in the shift rail pocket you can feel that the trans is actually very positive. However the shifter s are built with plastic bushings and weak bellvue springs giving a very vague feel. You can actually back the stops all the way out on the Hurst shifter and not notice any difference. I think Hurst is actually the only company to have stops, but I don't know that with 100% certainty.

My sunbird had a factory S10 shifter without the upper. I simply took the lower half apart and straightened it. It was every bit as positive as the aftermarkets and it had no stops
 
The Pro 5.0 shifter has stops. It is specifically designed for the T5 in a Third Gen Camaro. I hate to hear the OP doesn't like his. It's what I went with in my car but haven't finished putting it back together yet, so haven't had a chance to try it out.
 
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