whats the lowest horsepower ever in a ls1 trans am

**purplebat66** · 06-14-2008, 08:28 AM

Just curious if anyone had the lowest numbers on a stock ls1 trans am.I had my car at the vette doctors and to my amazement my car dynoed at a mere 234 horsepower they tunned it and now it has 286 horses which is really still low since i have a lid slp, catback exhaust, k&n airfilter and msd wires.The guys at the vette dr were great its a great place to take your ls1 car.I am just curious what could be holding my car back .They told me that the motor and trans were good and i have a feeling it could be the cats how do i find out if its the cats .Thank you for any help.

**joejenkinsglass** · 06-14-2008, 09:10 AM

it probably has a load of carbon build up from the whopping 234 hp just drive it hard and use good gas the engine should clean itself right up

**RandomOmen** · 06-14-2008, 09:13 AM

That is extremely low! What did they say about its low HP?

If the cats are clogged it should throw a code. The code it throws will indiciate which cat.

**Benner** · 06-14-2008, 09:28 AM

Are you running premium fuel?? and a clogged cat won't always throw a code. Seen it many times at work, even on vehicles only 2 to 3 years old.

**Mr. Luos** · 06-14-2008, 09:36 AM

Originally Posted by purplebat66

whats the lowest horsepower ever in a ls1 trans am

You win.

**blackbirdbrain89** · 06-14-2008, 12:15 PM

wow i have to say that might just be the lowest hp #'s from a ls1 ever. hell u might have a cloged fule filter or a fule pump going out... cats wont hold u back the type of cats that are one outa cars a knows as honey cones theay are not like that old type from the 80s ours dont clog. how meany mi is one ur car? ur car might be missing a lobe or some thing. i have never herd of a ls1 car losing lobes but u never know its also possable that the push rods may be bent and losing power that way as well

**purplebat66** · 06-14-2008, 12:20 PM

well i actually had the cars top end rebuilt and i its running perfect as of right now it has 286 rear wheel horsepower i know thats still pretty low i am giong to have the cats checked out next week.

**Cronex** · 06-14-2008, 01:36 PM

Originally Posted by Mr. Luos

You win.

...yeah, seriously.

**SVG210** · 06-14-2008, 04:23 PM

wow 234 are you shure its a v8?

**vannatte** · 06-14-2008, 06:13 PM

Originally Posted by hurraquio

wow 234 are you shure its a v8?

**tonyjnjz** · 06-14-2008, 06:36 PM

must have a ford 4.6L in it

**blackbirdbrain89** · 06-14-2008, 06:39 PM

u need to sell that car and get a diffrent ls1 car... the one u have must be a lemon or some thing

**vannatte** · 06-14-2008, 06:45 PM

There has got to be something seriously wrong with that car. I think my 86 IROC had more hp than that.

**tonyjnjz** · 06-14-2008, 06:53 PM

Originally Posted by vannatte

There has got to be something seriously wrong with that car. I think my 86 IROC had more hp than that.

rwhp???? they were like 205 flywheel....they maxed at 245 flywheel in 92

**purplebat66** · 06-15-2008, 04:55 AM

happy fathers day believe it wont have 286 horsepower for long

**Speed Psychosis** · 06-15-2008, 05:28 AM

check the spark plugs, front o2s, throttle body, maf, and filter. something sure as hell isn't right. my guess would be maf or o2s sense it seems to be a sensor problem considering a tune got you 50 rwhp.

**mrr23** · 06-15-2008, 05:51 AM

got me beat. the 99 TA i had initially dyno'ed 250 rwhp right after i bought it. did plugs, wires, and fuel filter and it did 278 rwhp.

**Benner** · 06-15-2008, 05:52 AM

Originally Posted by blackbirdbrain89

wow i have to say that might just be the lowest hp #'s from a ls1 ever. hell u might have a cloged fule filter or a fule pump going out... cats wont hold u back the type of cats that are one outa cars a knows as honey cones theay are not like that old type from the 80s ours dont clog. how meany mi is one ur car? ur car might be missing a lobe or some thing. i have never herd of a ls1 car losing lobes but u never know its also possable that the push rods may be bent and losing power that way as well

Sorry but the sentence in bold I have to argue. Since I started working at the dealership I'm at as an apprentice tech in January, the master tech i work with and I have had to change at least 5 sets of cats from GM vehicles that were at least a 2000 or newer. We have to cut the cats away from the pipes and take it back to parts for the core and most of them You can't see straight through at all.

Chances are they burn the centers out of the cats, but sometimes they will clog on you.

**jrc1122** · 06-15-2008, 06:11 AM

Originally Posted by purplebat66

Just curious if anyone had the lowest numbers on a stock ls1 trans am.I had my car at the vette doctors and to my amazement my car dynoed at a mere 234 horsepower they tunned it and now it has 286 horses which is really still low since i have a lid slp, catback exhaust, k&n airfilter and msd wires.The guys at the vette dr were great its a great place to take your ls1 car.I am just curious what could be holding my car back .They told me that the motor and trans were good and i have a feeling it could be the cats how do i find out if its the cats .Thank you for any help.

Holy COW!!!

ever thought of the possibility that they were fudging the system a bit, to make "their" custom tune appear to give you 54 HP. Makes them look like Gods, you go and tell all your friends and they get tunes as well. Perpetuation is the key to good business. And you just perpetuated for them.

**mrr23** · 06-15-2008, 06:13 AM

Originally Posted by jrc1122

Holy COW!!!

ever thought of the possibility that they were fudging the system a bit, to make "their" custom tune appear to give you 54 HP. Makes them look like Gods, you go and tell all your friends and they get tunes as well. Perpetuation is the key to good business. And you just perpetuated for them.

guess you missed this part. i'm not sure what he means by his top end rebuilt.

Originally Posted by purplebat66

well i actually had the cars top end rebuilt and i its running perfect as of right now it has 286 rear wheel horsepower i know thats still pretty low i am giong to have the cats checked out next week.