Out of curiosity how fast will a stock L03 run in terms of M.P.H.? I know it's goverened but how fast can you go before it hits the limit?

 

It appears to be 115. Might be different by year, but idk. Read the article below.



https://www.thirdgen.org/unlimited

 

My old 89 L03 would go 110 and no more. Gotta love the speed limiter....

 

My friends camaro did well over 120 with a LO3, 5speed and unknown gears probably 2.73 or 3.08 it's a RS. He took out the TBI and installed a carb and different distributor (Screw that Speed limiter crap) when he let off the gas it took a good 15 seconds for the speedo to start dropping from the 85mph mark. If I had to take a good guess I bet we was doing 130 and it was still climbing!

 

I installed a truck TBI ECM at one point in my attempt at tuning a TBI engine and i got her to go over 130. That's about it. (Truck ECM has no speed limiter) at least the one i got didn't....

 

Certain trucks don't have a speed limiter such as my 88 3/4 ton Suburban LO5 350 with TH400 does not have one, I don't think any 3/4 ton trucks do? I do believe all 1/2 tons with 700r4 or 4l60E do though...I could be wrong? Did you have a 5 speed? Seems like you would have to have one in order to do that mod, 3/4 ton trucks with TH400 tranny's the ECM has no control over the transmission, otherwise you would have to deal with TQ converter lockup and other issues. Just curious as how you got the 350 ECM to work on a 305? I know people who have done a 305 to 350 swap and had to change computers because the 350 would not run right with the 305 ECM.

 

I got my dates screwed up, Sorry man. It was after i did my L05 swap. Didn't make much more hp than the L03, just more torque. Shoved me harder into the seat on launch basically. But with the L03 ECM/Auto i ran her to 120 once.(after the speed sensor bypass mod) lol

 

well iv got a 92 formula with a LO3, 4L60 4 spd o/d, and 2.73 gears all stock and it will run until my speedo tops out at 120 and it still pulls after that so..

 

My brother did the L05 swap out of a 92 1500 truck and it had no speed limiter. He had the 120 mph speedo and it was pegged and still climbing it's fair share of times. He also did a T5 tranny so I'm not sure if that has anything to do with it.

Never really understood why they speed limited the L03 engine and not the TPI engines. You'd think the TPI's would have way more potential for top end and that they'd be the limited ones.

 

135 mph (220kmh) in OD , bypassed speedlimiter with TBI CHIPS, 91 Trans Am WS6 5.0 TBI, 4speed auto, 2'73 .

 

I didn't even know you could buy a 91 trans am with a 305 TBI. Guess you learn something new every day.

 

its an export model (Switzerland) RPO "EXP". see my cardomain page for details and RPO code.

 

Ahhhhh ok....so I'm not going fully crazy yet I guess. Sounds like it could be a rare car at some point. Looks like it's in nice shape too!

 

Just curious why ppl are bringing threads back from the grave quite frequently now? Just read the thread don't post...

 

Do 305 tbi cars with a 5 speed have a speed limiter?

 

Mine is an 88 so no limiter for me, then again with the EBL I don't have that problem any way,lol. My speedo is still off but I can probably do over 130mph now after the swap.

 

I got my 89 RS up to 115 mph with it still pulling and climbing until I caught up to traffic.

 

my governor is at 119 on my lo3?