526 SS 96

Good luck with it.

Danny McAdams

If you are using the 94 cam with splined shaft, I'll bet you are one spline off easy to do with an aftermarket cam. Tha symptoms you describe shows a spline advanced. I have fixed 4 94's in last 2 yrs, found same thing every time, when you pull opti off the shaft will be stuck in cam. Good luck. Danny Mc

Spitfire557

I did not understand that post at all. I have the '95+ opti.

street demon2k3

had just about the very same thing happen to me when i got my 355 together, 1/4 throttle and it would backfire like crazy put idled and revved to the limiter with just a few pops after 5k rpm. i changed out the wires, replaced knock sensor, readjusted valves, coils, MAP, Opti 2x, new o2's, rewired most wires coming from the pass. side where the LT's seemed to burn through, and about 7 sets of plugs. i tried tr55, tr6, A104's, and they all seemed to foul out causing some of the symtoms as well. finally got some ac delco platinums and everything has been fine for now. the most likely culprits were the wires, knock sensor, plugs which caused the car to run like ***. since i switched to platinums the car has ran like fairly well. good luck.

shoebox

He means he thinks the opti is installed wrong (yes, it can be done). You really should put "vented opti conversion" or something in your sig, so people will know.

NightTrain66

that is a very thorough post on rocker adjustment from 526 SS that describes it well. I would try 1/8 to 1/16 of a turn though.

If the tune is off, it will never be right. A scan will help you determine what the O2's, TPS, MAF and other sensors are doing and if they need replacing or adjustments.

Make sure the plug wires are not crossed (especially 5/7). Make sure the wires are new and on the right plug.

Firing out the exhaust can be opti one spline off as mentioned since that slows the timing down. Could be excess fuel burning in exhaust or lean conditions can cause this. Lots of variables. A scan would show alot more in these areas.

playa7970

so when the car is under a load and you accel it backfires right? is it like you have to gradually ease into it so it wont do it? im only asking because i had the same problem with my setup but after dyno tuning it and some help with some members i got that sorted out mail order tunes to me are good if you have a minor bolt on car but when you start dealing with major upgrades and mail order tune will only get you by im still working out some issues with my setup but ill eventually get there

Injuneer

The title of this thread is misleading... it isn't an "LE2 Problem".... it appears to be a tuning or other problem on an engine that just happens to have LE2 heads/cam.

irishz28

did you degree the cam when u put it in?

Spitfire557

The cam was degree'd by the previous owner and was fine.

Well, it is a problem with my LE2 motor, so yes, the thread title is correct. But thanks for pointing that out.

Sounds exactly like what my car is doing. I'm going to try bypassing the KM today if I can, see if that helps at all. I'll also double check all the plug wires. I'm running the AC Delco Platinum's gapped at .050". I'll keep you guys updated though.

CamaroSS30thAnn

i had a problem like this after my header install , first problem were crossed wires also had a problem with bad 02s

id say check ur wires first if u havent , if all fails pull of ur opti and check which hole u pu tthe cam dowel on , there should be 3( i think ) 2 shallow holes and one deep one, the cam down goes into the deep hole.

good luck man

would be nice to find out what ur problem is, im interested in the LE2 package

SS RRR

That's what I would check first. Make sure all wires are connected to the proper plugs. It's possible the timing chain could be off a tooth...

Spitfire557

I still haven't gotten around to checking the plug wires. Zigroid came over and we scanned it with his laptop. I'm pretty dumb at reading all the numbers, but I'm sure he'll chime in.

palehorse77

Did you ever figure out what was wrong with your setup?

It sounded to me like it was your tune, but clearly it could be a myriad of things.

After recently doing a new timing chain, opti, e-h20 pump & obd1 (pcmforless tune) cpu mine sounds to be acting very similar to yours. I've yet to do a dynotune. I was planning on getting the Tunercat software can you do the scan / data logging with it? I thinking I'd need Tunercat RT.

Colin

God damn that sounds nice. I hope my Vega comes even half as close.