GlockLT4

How many modified LT4's running stock LT4 (OBDII) computers? (stock means factory program!) I dyno'ed mine with the hot cam and only pulled 290rwhp, BUT i just stuck the computer in, let it idle for a minute then dyno'ed. I think even with OBDII i probably need to drive it around for a day or so and then it will learn a little.

Talking cam swap's here... no strokers or anything. Just like a cam/heads/headers package, or just cam.


[Modified by GlockLT4, 5:35 PM 2/22/2004]

Zix

I did heads/cam on mine and pulled 364ish, don't remember exactly. That was with the computer reprogrammed by Ed Wright. I haven't dynoed it ye with the new intake, headers, or electric WP yet. I'm runnin a Crane Cam (222/230@.50 .542/.562 112LSA)

Perfusion

Still very much a newbie here, but shouldn't an LT4 dyno around 300rwhp when stock?

GlockLT4

Yeah, i just put a cam in and need lots of tuning :). I pulled 296 completely stock. With the cam I got 312rwhp out of it by tuning my obdi computer. Stuck my obdii on there for one run real quick and it only did 290. I think it needs to learn a little before dynoing like that.


[Modified by GlockLT4, 3:30 PM 2/22/2004]

Dan Parker '96

On my LT1 to LT4/Hotcam conversion I found out that minimal changes to the stock program work best (I'm using LT1 Edit, EFILive v6 Pro, Alex Peper's OBD-2).

Stock timing and minimally modified (only over 4000rpm) fuel tables maximized my area under the curve.

After looking at your power peaks (5700-5800rpm) I'd say you've got some type of problem up top.

The Hotcam shouldn't peak until about 6400rpm... and then it'll level off.

My last run was 316RWHP, converter unlocked with (as I found out later after I exploded it) a POS converter. This was through the stock manifolds and cats.

Regardless of what your absolute dyno numbers say... they shouldn't peak until 6300-6400rpm. Again, your numbers seem to trail off about 500rpm too soon.

GS345

Im still running the ODBll on mine. got it tuned after the heads. ran stock program with, hot cam/headers/exhaust and dynoed at 343 or so.

jeff

GlockLT4

Yeah, i'm just trying to avoid the costs with programming the obdii since i have an obdi computer and know how to tune it with the software i have. obdii gets expensive fast. Reason for making this poll was to see how many people have the STOCK programming in there obdii computer running a 350 with a cam and headers maybe.

GS345

I did run mine stock till I added the heads/intake/52mm tb. It seemed to work fine, just kept the service engine light on alot of the time.

jeff

GlockLT4

:cool: :thumbs: I may have to give the stock LT4 computer a chance then :).

ericcer

No dyno numbers just track numbers. I do a 8.0 @ 90 mph with the hotcam and longtubes.

Sounds like your ODBI PCM has a better tune in it than the ODBII. I have heard that an ODBI PCM can give you about 5 hp more than an ODBII.


[Modified by ericcer, 8:43 PM 2/22/2004]

MongooseLT4

Dynoed 311hp 300tq with hotcam only.....I'm sure thier are better numbers with a tune.