tbi rev limited?
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Car: 88 firebird formula
Engine: 5.0 TBI
Transmission: auto
tbi rev limited?
Does anyone know whether or not the 5.0 TBI engine is rev limited via the ecm? Mine seems to run out of power at 4000rpm.
even with the limited cfm rating of the factory TBI, it seems that it should pull farther than that!I have added an open element 14 inch air cleaner, and bumped the timing up to 4 degrees btdc.
Still has the same problem.
Anyone have any input?
even with the limited cfm rating of the factory TBI, it seems that it should pull farther than that!I have added an open element 14 inch air cleaner, and bumped the timing up to 4 degrees btdc.
Still has the same problem.
Anyone have any input?
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Car: '90 RS
Engine: 377 LSX
Transmission: Magnum T56
Re: tbi rev limited?
Originally posted by oldred88
Does anyone know whether or not the 5.0 TBI engine is rev limited via the ecm? Mine seems to run out of power at 4000rpm.
even with the limited cfm rating of the factory TBI, it seems that it should pull farther than that!I have added an open element 14 inch air cleaner, and bumped the timing up to 4 degrees btdc.
Still has the same problem.
Anyone have any input?
Does anyone know whether or not the 5.0 TBI engine is rev limited via the ecm? Mine seems to run out of power at 4000rpm.
even with the limited cfm rating of the factory TBI, it seems that it should pull farther than that!I have added an open element 14 inch air cleaner, and bumped the timing up to 4 degrees btdc.
Still has the same problem.
Anyone have any input?
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Car: '90 RS
Engine: 377 LSX
Transmission: Magnum T56
Originally posted by vic_V8
valves tick at like 5500 rpms don't they? (in stock engine)
valves tick at like 5500 rpms don't they? (in stock engine)
#6
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Shifty, do you honestly think an L03, even stock, won't make power past 3500 rpm??? Come on now, that is taking it a little far don't you think? 4k maybe, but I don't buy that either. I know of one member here with a verified dyno who's peak hp was at 4700 rpm with only full exhaust and nothing else. I myself shaved off half a second of et by shifting at 5k rather than 4400 rpm. Granted that's still not very high compared to my LS1 that I shift at 6400 rpm, but it's not 3500 bad, lol.
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Car: '90 RS
Engine: 377 LSX
Transmission: Magnum T56
Originally posted by 25THRSS
Shifty, do you honestly think an L03, even stock, won't make power past 3500 rpm??? Come on now, that is taking it a little far don't you think? 4k maybe, but I don't buy that either. I know of one member here with a verified dyno who's peak hp was at 4700 rpm with only full exhaust and nothing else. I myself shaved off half a second of et by shifting at 5k rather than 4400 rpm. Granted that's still not very high compared to my LS1 that I shift at 6400 rpm, but it's not 3500 bad, lol.
Shifty, do you honestly think an L03, even stock, won't make power past 3500 rpm??? Come on now, that is taking it a little far don't you think? 4k maybe, but I don't buy that either. I know of one member here with a verified dyno who's peak hp was at 4700 rpm with only full exhaust and nothing else. I myself shaved off half a second of et by shifting at 5k rather than 4400 rpm. Granted that's still not very high compared to my LS1 that I shift at 6400 rpm, but it's not 3500 bad, lol.
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#8
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Car: White KSwisses
Engine: 5.3L Gen III
The car isnt rev limited, but it is speed limited (at least in mine) at 107 mph, then the fuel cuts off. A bitch if you changed rear-end gears without recalibrating your speedo.
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Car: 88 Camaro SC
Engine: SFI'd 350
Transmission: TKO 500
Axle/Gears: 9-bolt w/ 3.23's
To the best of my knowlege, the 88's didnt get the speed limiter set as they used a different ecm.
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Car: 91 Red Sled
Axle/Gears: 10bolt Richmond 3.73 Torsen
It isn't limited in stock code but if you want one it can be patched in. The patch basically changes the code to look at engine RPM instead of MPH. RPM = 8-bit value * 25 while MPH is just 8-bit value. So if your "mph limiter is stock" at say 107, then 107 * 25 = 2675rpm limiter. That's good for keeping your friends from romping around . I set mine to 6000rpm (6000/25= 240) and resume just below that.
That patch can be found on the DIY-Prom board.
https://www.thirdgen.org/techbb2/sho...hreadid=108380
That patch can be found on the DIY-Prom board.
https://www.thirdgen.org/techbb2/sho...hreadid=108380
#11
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Car: 1991 Camaro RS
Engine: Briggs & Straton
Transmission: Centrifical Clutch
I once accidently burried my tach. For a good couple of seconds. She ran a little shakey afterwards, but run the same as always. From what I understand, the speed limiter on the RS's is 112 (actual, now what the inaccurate gauge shows).
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Car: 96 Silverado/99 Suburban
Engine: 700 cubic inches of 'Muican Awesome
Transmission: 4L80/4L60
Axle/Gears: Chunky/Clunky
These LO3's are strong as all hell. I've also missed a shift before and buried my tach, still ran great. I've also buried my temp. guage as well. Ran like it was still warming up...
#13
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Car: 1990 Formula
Engine: 305 TBI (LO3)
Transmission: 5 speed manual
Originally posted by 90RS305
These LO3's are strong as all hell. I've also missed a shift before and buried my tach, still ran great. I've also buried my temp. guage as well. Ran like it was still warming up...
These LO3's are strong as all hell. I've also missed a shift before and buried my tach, still ran great. I've also buried my temp. guage as well. Ran like it was still warming up...
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Car: 96 Silverado/99 Suburban
Engine: 700 cubic inches of 'Muican Awesome
Transmission: 4L80/4L60
Axle/Gears: Chunky/Clunky
Originally posted by Formula4Speed
170 hp can't hurt anything except your ego :lala:
170 hp can't hurt anything except your ego :lala:
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Car: '86 Camaro
Engine: 406 Small Block
Transmission: 4 Speed
Axle/Gears: 3.45
Originally posted by dimented24x7
To the best of my knowlege, the 88's didnt get the speed limiter set as they used a different ecm.
To the best of my knowlege, the 88's didnt get the speed limiter set as they used a different ecm.
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Car: 1992 Pontiac Firebird
Engine: Lo3 305
Transmission: th700-r4
Axle/Gears: stockers
88 not speed limited?
Is it true that in 88 an lo3 equipted car is not speed limited? I have a '92 but I put a 88 ecm ( I'm not sure on the id) in there. It runs great but is it now limited? Just wondering.
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Car: 91 Red Sled
Axle/Gears: 10bolt Richmond 3.73 Torsen
Speed limited by bcc;
https://www.thirdgen.org/techbb2/sho...hreadid=260438
https://www.thirdgen.org/techbb2/sho...hreadid=260438
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