Hi I've been searching through threads and have gotten some good Ideas but thought I'd post this just to see if any more can be suggested on my problem.

Did these mods on a 2001 with 19k on it.

232/230 595/590 on a 114 XER cam
Ported heads with stock vavles and just resurfaced .005 and a vavle job
REV springs and Titanium retainers
Combination MS 7.4 chromoly pushrods
NGK Tr55's at .50 gap (out of the box)
Kooks LT's with ORP
Predator standard tune (was going to do custom after getting it running)

Everything else is stock I believe. Installed it all, did the exaust and installed all 4 02's for now. Its a six speed car. Started it, it ran great for about 5 seconds has great oil pressure then started running like complete crap. Shaking ALL over the place rich as hell, pouring smoke out the back. Made sounds everyonce in awhile sorta like a back fire. But for the most part valvetrain was quieter than I expected.

It does idle it doesn't die. If you give it any gas it might those it staggers really bad. Did get a light and am checking that later today although I'm sure its a misfire...

Had VERY competent help on the install Chris (Viseral on this board) has done a crapload of these swaps. Cam was installed dot to dot for sure. Seems like all cylinders are firing so it doesn't seem to be ignition. Chris thinks its pushrod length they are too long and keeping the vavles open, I'm REALLY hoping that is it cause thats pretty easy. I ordered a pusrod length tester and will have to figure out how to use it

Also don't know the base circle yet I am asking the shop I bought the cam from.

So pushrod length will hopefully be it but I was wondering is anyone else had any other suggestions that I could check while I'm in there??

Thanks!!

Bobby

 

I don't think the pushrod length is the trouble. I've done several cars with just a cleanup cut on the heads and 7.4in pushrods without any troubles. If all of your sensors are connected (MAF, O2's, etc..) and you don't have a leak on your intake.. it would have to be related to the tune.

 

I agree with Gomer on the tune. My sons car fouled out the plugs it was running so rich after the H&C install. We slightly drilled out the throttle body to get it idling as it would instantly die. Cleaned off the maf and 02 sensors and its drivable now. We're getting our cars dynotuned this tuesday which will help drivability and power alot. Go over all your connections and make sure everything is properly connected.

 

How much does the tune have to do with the first 60-90 seconds of start up. I didn't run it that long really no way I could drive it. I figured with relatively stock tuning it would at least run maybe have to give it a little gas to keep it from dying etc. but this is BAD, not tuning bad but BAD.

I will try the custom tune from James to see if that helps it should get it close. But I don't think so.

The O2's shouldn't matter at first right? The MAF, etc is plugged in. The only thing I think might be mesed up and I HIGHLY doubt it is somthing to do with the rear grounding straps but the car wouldn't start in that case right?

I thought 7.4's would be fine too. but maybe the vavle job screwed things up? Maybe a bent valve?? (which would REALLY be ridicoulus)

Really there are guys driving similar setups on stock tunes. This is not drivable. Its not pouring out black buffs when you give it gas. Its pouring out black clouds at IDLE. You give it any gas and runs worse...

But I appreciate the suggestions I will install the mail order tune (should be relatively close) and try it in the morning. If I did it tonight I think the neighbors might get a little pissed it is VERY loud

Thanks again!



Bobby

 

I am new here but I have a lot of LS1 experience, pulled my 98 apart more times than I care to count. With a cam that size it will run like crap until it gets on the dyno and is programmed correctly.

 

Did you guys do a basic check for piston to valve clearance? 232 duration with nearly .600 lift is gonna be on the edge. Maybe that is part of the issue?

Dunno about tuning, i've seen cams that big go in and they certainly didnt do what you are describing. Sounds like there may be something else wrong, but I have no idea what.

 

93TAWicked1,
I just got my h/c done on my WS6 about three weeks ago. The tune has alot to play with the start up. We had to work on mine a little bit to get it right. I think after you get it tuned right you will have know problems at all.

 

Well everyone I talked to including Jantzer (who sold me the cam) and Combination MS who sold me all the accessories assured me that as long as the heads weren't milled PV clearance wouldn't be a problem We did turn it over by hand a number of times and had no problems whatsoever. very smooth (well as smooth as you can expect) Plus would PV problems make some noise? The vavle train is pretty quiet I expected the sewing maching effect but not alot of tinging noises just the horrible blub blub idle and occasional rap backfire like once every 90 seconds. Plus the smoke out the rear is crazy I've had cars with rings go out have less smoke than that!!!


JMX thats kinda what I thought too it would run bad without programming but not like this. Guys but GX5's or whatever in without programming and can still drive the car.

This car is not drivable. My 93 had tuning issues and it didn't run great sometimes but you could drive it down the street even in its worst tune...

But seriously I'm NO expert by far so I appreciate the suggestions and will probably even try the tune tonight just to see what happens I just need to upload it to the ECM! Screw the neighbors

Oh I hope it isn't PV clearance or vavles or anything like that I REALLY don't want to pull the heads again at this point!

Thanks again everyone!!

Bobby

 

Did you hear any knocking or such upon start up? I don't care who sold you the cam but P to V should always be checked as the cam a tooth off will cause a collision. I don't think this is the case in your situation. Pull the plugs and look at them they are probably fouled out causing it to run this way.

 

No the first 5 seconds or so she Ran BEAUTIFULLY, then just ran like crap. I can see your point but not being a mechanic I have to depend and trust certain people. From now on I will check PV but how do you do that? The only method I've heard of is the clay method and that isn't always perfect either???


I'm sure the plugs are fouled at this point. I'm going to do this first, but if I don't fix whats wrong with it they are just going to foul out.

No knocking just idling REALLY bad and alot of smoke. I did turn the motor over by hand and NO hangups. IF PV was REALLY bad like a tooth off wouldn't this become apparent here? Plus we REALLY checked and doublechecked the dots lining up on the cam install.

So I'm going to try the easy stuff first. I'll pull the plugs tonight and upload the tuning. In the morning reinstall the plugs and try and fire it up. I''ll pull the vavle covers tonight too and see if there is anything broken in there. I doubt it there was no crazy sounds like that but you never know

 

Its normal for alot of smoke as it is burning off of the engine/exhaust as it heats up. If you spun the motor by hand your P to V should be fine. The engine will run rich until it is tuned with that kind of cam. A dirty maf sensor or bad o2 sensors could also cause a further rich problem. You can spray them with brake clean and try that. I think if you install a fresh set of plugs you'll be totally suprised. It won't run well until you get it tuned but like a drag car you'll have to clean it out to keep the plugs cleaned off and keep it from dying.

 

Dave I really do get your point and appreciate it. But this is the fourth H/C swap I've done (1st on an LS1 though the rest were LT1's) I know about the smoke off the headers etc. This is not that kind of smoke this is out the tail pipes constant smoke and I did let it idle for awhile. I don't think the O2's don't even matter until the car goes into open loop but I could be wrong on that. The MAF, unless it got dirty sitting on my bench is fine.

The plugs were new, If I install new ones they are going to foul out again. The car isn't just not running well. If not in running condition while I said before I'm not a mecahnic I do know enough to tell the difference and Chris was there as well who does have alot of LS1 experience.

Again I appreciate the advice and am by no means disagreeing with it. I'm just taking the other side explaining the situation the best I can to see if that changes anything

Again this isn't bad running like it just runs like crap. This is the car is shaking and its scary to let it keep running and remember is is just a 114 cam I've always ran 112's and the shaking is EXCESSIVE!

 

Did you check lifter pre-load?

 

I also say double check the spark plugs, Maybe one of them or one of your plug wires went bad. The smoke though kinda makes me think there may be something else going on. What color is the smoke? It might seem a bit much but you can try a leakdown as well if worse comes to worse.

 

The very first thing you NEED to do is get a QUALITY tune then diagnose the problems.

 

Actually the preload I am going to recheck after replacing the spark plugs and uploading the tuning. I will let it run a little then take the vavle covers off. Did a search and there are a number of threads on Preload and they all say different crap.... Any body have any suggestions on that? We installed the rockers torqued the bolts to 22 and then rotated the engine numerous times and checked them again and they were all at 22.... But if there is a more precise way I'd love to hear it

Smoke was bluish black, it was fuel it stunk up the whole garage on driveway pretty bad. Nieghboors even came over and made a few jokes

 

Mine did that the first time I started it up. But stupid me forgot to connect the 4 spark plug wires on the passenger side. Doh! And after that it ran fine. Except that I had to drill the throttle body plate so it would idle. I did the same on the rockers, 22ft/lbs, turned engine re-torqued and all was fine. Check the back of the intake and make sure the map sensor is connected. Mine wasn't and it took me a couple of hours checking connections to figure it out. Hope you get the problem fixed.

Peace
Ever

 

BTW - I still haven't changed my plugs. And tuning didn't help it that much. Idle was more refined and I gained 10rwhp.

 

I had a cracked plug do the same thing, it drove me nuts. My car backfired like a shotgun at the back of the car.

 

I would also guess that the coil pack could have been left unplugged on one side. Once you pull the plugs and check to see which ones are fouled you can establish a pattern to the problem if there is one. A compression test is also easy enough to do.