dath

So the 383 I've dropped in has been suffering from some knocking. I finally squared away my timing and am getting a maximum of 36* of advance at a little over 3000 RPM. I am not currently using my vacuum advance. . .

I am still getting knocking with this setup, but it only seems to happen when the engine has warmed up to full operating temperature (165 degrees or so, it doesn't really get any hotter normally). I am guessing this is caused by the spark plugs. Normally I would think that I had too hot of a plug installed, but I'm not sure that is it. I'm running Delco R43TS plugs now (engine should be about 10:1 and was supposedly dynoed at 427 HP). The problem is that my plugs are fouling (oil fouling it looks like). I'm thinking that the gunk on them is maybe heating up and causing the knocking. The engine is consuming a fair amount of oil (2 quarts per 500 miles ). I have about 900 miles on it at this point and I think it is still consuming oil.

I was thinking of switching to NGK plugs since they have a shorter ground strap and are thus more suitable for nitrous applications (which I'm planning on as soon as I get everything else working properly). I picked up some YR5 plugs and was going to gap them at .045" (I'm running a stock style HEI setup). Should I go colder, hotter, what?

Also, do you think this kind of oil consumption is "normal" on a new engine? Last I checked, the compression on all cylinders other than 2 were very close together (around 195 psi), which to me would indicate the rings were steated in (with the possible exception of those two cylinders). . .

Regards,
-dath

BB wowbagger

Have you considered using the R43T which doessnt have an extended tip?

dath

So the 'S' designates extended tip then? No, I hadn't, I didn't know it existed. At this point, I'd try just about anything, but it would be nice to kill two birds with one stone so to speak. . . Get rid of the fouling and fix the issue, which I am suspecting are related, but maybe not. I'm not even sure they are still fouling as it takes a while for them to get that way. . .

big_G

I think the oil comsumption is abnormal. I would address this problem first.

dath

big_G, what would you check first for oil consumption? The engine does have a high volume pump and I sometimes wonder if that may be part of the problem. . . Should I get a leakdown tester and see what that tells me first? What kinds of things would cause the excessive consumption? Rings not seating, valve guides, valve seals, that kind of stuff you think?

-dath

big_G

You need to check all the things you listed, including the PCV system and intake gaskets. The rings won't pass that much oil, unless the gap or fit is way off. With 900 miles, they should be well seated by now.

dath

Sorry to show my ignorance here, but how would I check the intake gasket? Obviously I could pull the intake and replace the gasket, but I'd much rather not do that if it isn't the problem. My intake was way loose for some while before I noticed and retorqued the bolts. Maybe it didn't seal up well after the retorque. . .

Also, is it possible for the PCV to suck oil up and cause the issue? Man, that would sure be a simple fix I know my PCV rattles around, but I have noticed that the vacuum hose that I have connected to it seems oil saturated (all the way through ???) for some reason . . . I don't have a baffle on the valve cover behind the PCV either . . .

I just called around and I can't believe that none of the parts stores or Sears carry a leakdown tester in stock. I'd have to fix my Harbor Freight special air compressor anyhow Why is it that everytime I get ready to fix a problem I end up being short one part or tool??? Is it just me???

EDIT: Also, I forgot to mention, my pistons are forged as well, so I would expect a little looser tolerance, but that shouldn't cause the problem I wouldn't think since they heat up and expand to fit?

-dath

big_G

You do need a baffle for the PCV. At higher rpm's, the oil splashes around pretty good, and the pcv will suck oil. I would pull the intake and reseal it. Forged pistons won't change oil consumption.

dath

big_G, thanks a bunch. It's so nice to be able to ask questions and get answers so quickly. Now I just have to break it to the wife that I need a new set of valve covers. Any gasket recommendations for the intake? Also, any recommendations on how to torque the center two bolts on both sides of the intake? They are angled in such a way there the only thing I can get at them with is a crow's foot and I managed to round a couple of corners that way

-dath

big_G

Your welcome, dath. In tight confines, I use 12 sided bolts so I can use a 12 point wrench. Don't worry about torque, you can't overtorque when using a 10 inch wrench. I use fel-pro gaskets almost universally. I also re-torque them again the next day.

dath

Slick. I also think I found the solution to my baffle issue as the wife was just complaining about me spending more money so I decided to look for something that would be lower cost. . . Looks like Moroso makes a grommet with an integrated baffle:

http://store.summitracing.com/defaul...=KeywordSearch

I'll see about getting a better set of end wrenches (just have some crappy import ones now, time to upgrade to some crappy Craftsman ones) and a set of 12 point bolts instead of the 6 pointers in there now . . .

-dath

dath

And even better yet, my local speed shop had two of the PCV grommets in stock, so I bought one and put it on. I'll see if that helps, if not, I think I'll pick up a leakdown tester and see what it tells me. The intake may be coming off pretty soon too.

Thanks for the help guys. Once I get this oil bit solved, I think I may try the R43T delco plugs (short snout).

-dath

Brettmc

What intake are you running?

Brett

stingr69

If the intake was not tight when the sealer was curing that could be where these issues come from. The intake gasket can leak pulling in the oil causing the plugs to foul. The oil could be causing the detonation.

I would reseal the intake first and change the plugs to see if that stops the oil consumption. Pull a plug after driving to see if they look any better. Those 43's are a cold plug and will foul easily in regular street driving. A hotter plug will burn off the crud better. Try some 45's untill you get this sorted out. Switch back over to colder plugs when you start running it hard if needed.

-Mark.

guvnerwl

What's your initial timing? I would pull 4 degrees off and see if knock goes away - easy to do - good info.

dath

Brett - I'm running an Edelbrock Performer RPM.

Mark - Good suggestion, I think maybe I'll just do it then if it is likely the cause of the problem. I know the intake was loose enough to be leaking oil at the front and rear of the engine before I retorqued it. It was like that for quite a while I'm sure (several hundred miles at least).

guvnerwl - Initial timing is around 13 degrees. I suppose I could back the timing off a little more, though I was completely unable to get it to knock until it warmed up, at which point it became trivial to just blip the throttle while going 40 MPH (or other conditions as well) . . .

Regards,
-dath

Brettmc

I'm having a hard time getting my rpm air-gap to seal. I used the standard Felpro intake gaskets and it wouldn't seal. Edelbrock suggests their part # 7203 or Felpro #1212 (this is for a bbc tho). I used the 7203 last week. What gaskets did you use?

Brett

dath

Not sure which gaskets were used, they were installed by the engine builder. Stupid me didn't retorque the intake right away either as I didn't know when it was supposed to be done and the builder didn't mention it. I'm sure it isn't helping my problems, though I really wish I knew how to tell if it was the intake causing the oil consumption for sure. Swapping the gasket will only tell me if it stops, if it doesn't stop, it could just mean that I didn't do a good job swapping the gasket. . .

-dath

Brettmc

You can see some things with the intake off....like soggy intake gaskets....like oil in the head intake ports....like coke on the backside of your intake valves...like oil runners in the intake manifold....all will tell you something about your engine. It's not really hard to pop the intake, should only take about 30 minutes. The only cost is some time, rtv, and a good set of gaskets.

Brett

dath

Thanks Brett. I have just never had an intake off before, so I wasn't sure what to look for. I know the basic procedure for replacing the gaskets and everything as I've read many posts about it before. . . You are right, I can't imagine it taking me more than 30 minutes to take the intake off. Probably take me a couple of hours to put it back together again as I'm a bit slow and haven't done it before. . . It would also give me an excuse to replace the bolts as I rounded one of them and started to round another trying to use a crappy crow's foot on my torque wrench. If only someone made box ended crow's feet then I could be happy that I can get an approximate torque set still without rounding the heads of the bolts. . .

-dath