Hmmm, where'd THIS come from?

YES, it did come off my Riv today! Replaced it with a PEM I ported out a few months ago. This was not a fun project, but didn't turn out to be quite as difficult as it had appeared it might be.

I put in about 2.5 hrs on the job, taking my time and being careful with the studs. All the manifold studs and/or nuts came off w/o much trouble at all. I sprayed PB Blaster on all, but gave them a try immediately just to see if they felt like they were going to give me a hard time. One thing I'd do differently is to go buy a 6-point 13mm socket, instead of using my 12pt sockets. One nut rounded off a bit the last bit of tightening, and I'm sure a 6pt would have prevented that.

Aaron, you kind of downplayed the removal of the heat shield in your headers thread, but that shield was easily my biggest aggravation today. The lower screw was a complete PITA both to remove and to re-install. The dipstick tube was also a problem, but easily solved by pulling the tube out of the hole a bit to gain access to the lower #3 bolt.

A couple questions... I deemed it next to impossible to remove a manifold gasket, clean up the mating surface, and put back on. BECAUSE, I could not determine if there was even a gasket there. Certainly couldn't get my head in position to see a gasket, and couldn't find one with my fingernail at the edge of #5 port either. So I decided to just slap that PEM on and get it over with. Did these engines for SURE have a SS gasket from the factory? I've read references to that fact. Odd thing is, Buick's 350's and 455's back in the 70's came without an exhaust manifold gasket. They simply weren't needed.

Also Aaron, I forgot to do it right away, but you said to disconnect the battery before starting. What was the reason? 2 of them come to mind for me, but I want to hear yours first.

Anyways, got it all put back together, hooked up the battery, and fired it up. No hints of an exhaust leak, so it seems I got it sealed up pretty well. Did about a 10-15 minute easy drive around town, and a short couple of Interstate miles and back home again. Didn't push anything, just letting the PCM figure out what's going on.

I decided to get this done ahead of time, before my DP and new Cat install. The cat is ordered, should see it in a few days, and I have a week off starting Sept 10 to get it ready in time for a Street Legal date Sept 16. Just going to make a few runs, see what kind of gains the PEM, DP and hi-flow cat give me. Of course, first I'll hook up the LS1M and see if my KR situation has been resolved... If not, I don't know the next step. Need to find someone close enough to do some tuning I guess.

When I called my local buick dealership, they could not find a P/N for the gasket. I couldn't find it in the catalog at first either, but I did find the GM # somewhere.
I ended up ordering them from carquest.

Dave, mine had a gasket. I still have it if you're interested. I'll clean it up and send it to you free of charge. Sorry to hear of the difficulty you had. I had no problems removing the heat shield. The oil dipstick is held in with one screw, then pulls out. My manifold nuts came off easily too, but that could be because I used 6 point sockets.

Why do I disconnect the battery whenever I work under the hood? Once I was doing a job that was purely mechanical, so I thought: no reason to disconnect the battery? I got so far, then the valve cover didn't come off the way I thought it would, so had to unbolt the alternator to get clearance. To unbolt the alternator, I thought first I'd take off this black cable...

I'll just say in my case, it's not normal to think, "Wait, you're removing a big wire stupid! Go disconnect the battery!" I was focused on getting that cover off, still thinking this was a mechanical job, not an electrical one. Plus, the wire was black, so it didn't shout, "I'm hot!".

Well I dropped that wire, it touched the fuel rail, and fuel was ignited by spark as it welded a hole right through the pressurized rail. It took .1 secs before I had a situation reminding me of Saudi Arabian oil wells during the Gulf War. Luckily I had a rag in my hand, and put that fire out in short order.

So now I disconnect the batt whenever I work under the hood, because you never know when you might need to change direction during the job. Same reason I use jack stands to hold the car up. Jacks work fine most of the time, but then I remember that one time...

Aaron, thanks for the gasket offer. No need though, I'm fine with it as-is. There's no hint of an exhaust leak anywhere, so it's either sealed up tight w/o a gasket, or I simply didn't have good enough access to get at it, and it's right where it belongs.

Ah, the battery disconnect... I even thought about this just before I started working, then totally spaced it out. Until I was trying to loosen the lower heat shield screw. Apparently my wrench touched where it shouldn't have (sure as hell couldn't see what it was touching) and I got a mild shock with sparks, and the wrench handle became a few degrees warmer. No apparent damage to anything though. So out came the seat and off came the cable. The other aspect I was thinking about was having the computer re-learn for the better flowing front side exhaust. Maybe not enough of a diff with a PEM to be necessary.

The dipstick wasn't any big deal, and the heat shield will be easier if I do this again sometime. Reinstalling the lower screw was a b*tch, at least getting the threads started was. A magnetic socket would help.

Anyway, on Tuesday I'll try to hook up the LS1M and see if this helps at all with the KR. Should be doing the DP and cat next week while I'm off work.

Off-topic question: I may be trying some flexible tubing for a 4" FWI next week also, will have to locate the IAT sensor elsewhere. Best to tap it into a 45deg elbow at the TB, or into a 45 elbow at the other end of the tubing, near the filter? (may not even need one there though)

When given the choice, I've always thought it a good idea to locate the IAT sensor as far away from the TB as possible. Reason being, you should get a more accurate reading. The TB wicks heat from the engine to the intake, and could warm up your sensor if mounted too close.

Go to a clubgp forum around you there should be someone there who can tune for you if theres noone on here that can.

How much KR were you seeing before?

SpaceBar wrote:

Go to a clubgp forum around you there should be someone there who can tune for you if theres noone on here that can.

How much KR were you seeing before?

I started to see up to 5-6 deg when I did the 3.6 pulley, so needless to say, I've been driving nicely for a couple months, no hard acceleration runs.

There's a MNclubgp, but they're based 4 hrs away, not making that trip just for a tune, not yet anyway.... Also DakotaWbody.com in SD/ND, but I haven't read there of anyone doing custom tunes for others. Correct me if I'm wrong here, but I'll need to go to someone that is licensed to do 3800 tuning commercally, right? Or someone else running a Riv? For instance, someone with HP Tuners for their Regal GS wouldn't be able to tune a Riv, right? Aren't they limited to only a couple vehicles that they have to specify upon purchase?

Aaron, I'm thinking about putting in my TB spacer next week also, which would help cool the intake side. Not sure if I'll actually try to install the FWI, or just pull out the stock box and do some test fitting for now. I'd kind of like to make a couple/3 runs on 9/16 with just the PEM and DP/cat added.

When you did the first KR scan, did you record the ambient temps, fuel type, IAT, LTFT, O2, RPM, or any other important data? Oftentimes you can better pinpoint the cause when you can see what these other variable are. Also, when you do your new scan, it's important to have all these variables the same in order to get a consistent scan.

I've seen drastic differences in KR with 10ºF difference in outside temp, using same octane fuel from different stations, or if my intake temps are up from sitting idle. Mods can give results, but you can't always see them if other conditions are against you. I have to think to have that much knock with a 3.6", something wasn't right. I don't think you ever found out what it was.

TB spacers are one of those mods that should work, but results have not been impressive, imo. Furthermore, it's cheap, so lots have done the mod and some have had coolant leaks into the TB. It's recommended you plug the coolant passages in the TB, or know how to seal the gasket so it doesn't leak internally. I've seen some nasty picture from some pissed off modders who thought they had things under control. I don't have a spacer on mine, nor do I plan to at this time.

My pre-3.6 scans were in much warmer ambient temps, probably about 10deg warmer, and I saw a high of like .50 deg KR, IIRC, including going WOT. I don't have recorded scans, just was using it in gauge mode to watch the KR range. I REALLY haven't had time to seriously look into how to use this scanner best. Is it any wonder I'm very hesitant to consider a tuner? With 2 young kids, and both of us with demanding jobs, car time is scarce.

BTW, fuel was 92 from the same Amoco station, as always. I've also done a lot of reading on the supposed pros and cons of running a TB spacer, and I think it's worth trying out. I wouldn't doubt if many leak issues are due to improper installation. I think with the right sealant, and properly torqued bolts, there shouldn't be a problem. I likely will wait til next spring though, now that I think about it. Haven't decided on what sealant to use, have to re-read some of the online data again.