A overlay of my LS1 vs 305tbi compared.
it's fun seeing what modern technology gets you.

1992 305tbi/700r4 was a 140K+ mile unit with a Cat delete. Otherwise 100% stock.
LS1 is from a 2001 firebird.(+T56 Mag-F)
216/220 0.600/0.600 112 Lsa cam.
(TSP Stage 2 truck cam high lift)
Long tubes + dual 3in + 2 Vibrant Bullet mufflers + SpinTech 3000 muffler with side exist exhaust.
Crank scraper from Improved racing
ATI diaper, 10% under drive.
Other than that, it's a basic LS1.

I'll have future vidoes on the 0-60mph results and top speed at a road course in the future

​​​​​https://m.youtube.com/@3rdGenGuy/videos


Overlay of both engines from a AWD Mustang Dyno.

LS1 only

Original 305tbi. That torque curve is hilarious

 

LS1: 368rwhp/360rwtq
305tbi: 122rwhp/208rwrq (not including the weird converter spike)

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1.2G sustained turns at full throttle with no oil controll revving past 5,000rpm. The 305tbi was a champ. Continues to live in another 3rd gen.

 

Wow!...

 

LS1 with baby cam and long tubes. So simple, so good. 10x more fun to drive than stock.

 

Big oof on that 305 chart, could it even break the tires loose before? That must feel like a rocketship in comparison.

 

With Warmed up race tires, the 305tbi wasn't able to spin the tires at all.
The LS1 has surprisingly good traction in 1st gear.

 

At 1400rpm that LO3 was beating down that LS1! Ha, that was actually hard to type. Very solid build. What tires are those. They look identical to my RE71R's. They hook hard even with hundreds of rwhp.

 

Those are RT660s,
there's like 6 200tw tires that looks basically the same.
​​​​​I don't like them.
they require far far too much heat to work compared to tires like the CRS new re71RS or A052.
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If you don't tell us it's "Original 305tbi" we'd believe the exhaust is plugged or something like that! It's almost GM was aiming at making the car move from take off, feeling powerful, but choke it after for fuel economy.

 

That's like my Jeep Cherokee 4.0L I6. The faster you revved it the slower it went.

 

LS Engines are like fat ugly girls... They not much to look at but they work harder, perform better, stand up to more abuse, and stay with you longer.

 

That's because they can't run away. (there is no plus-sized smiley).