ChrisLS1Bird

Guys,

I have inherited a '97 M6 Camaro with a 383 LT1 (see sig). There are a variety of mechanical problems with the car that I am trying to resolve. I have a few starter questions that I hope someone on here can answer for me.

1. I think that the car has at least one blown head gasket. The car has an electric water pump that had wiring issues and may have cut off and allowed the car to overheat.

I have yet to do a compression check, but what do you think of this oil (pics below)? Seen this before? I'm hoping it is milky because of coolant, not indicative of a major problem in the shortblock. Note that just a few cycles of idling after changing the oil and it's already looking slightly cloudy again (no pic of that).

https://picasaweb.google.com/data/fe...photo&hl=en_US

2. Can someone point me to the best replacement head gaskets for this car? Cylinders have to be 30 over, right? Also not sure about the thickness of the gaskets I need. I have AI heads that are supposed to net 11.X:1 compression, so I'm not sure I need extra thin gaskets that increase the compression any more. But maybe I do. Really don't know what to buy, so please help...

3. Will I need new head bolts? If so, which ones?

4. I want to send the PCM in for a mail order tune. I believe the car has 1.6 roller rockers on it. Should I account for these when I describe the cam specs? If so, how?

Thanks for any help.

-Chris

Injuneer

Link goes to a Picasa site that requires a user name and password.

With a cam that big, you want a hands-on dyno tune..... not something for a mail-order tuner to do.

Black_Z

If you have the time and ability I would pull the motor from the car this winter and put it on a stand, tear it down and inspect all of the bearings, internals etc. I would give the guys at AI a call a see what they recommend for your heads - Cometic might be the way to go. I would put it all back together with new bearings, ARP hardware and a new oil pump for good measure. After dropping it back in the car, you can chase down the minor issues after that. Definetaly put a new electric water pump in it and wire it up right.

ChrisLS1Bird

I believe the link is fixed.

There is no shop locally (in Houston) that still tunes LT1s. Bryan at PCMforless says he can get me a good approximate tune. Of course I want dyno tuning, but I'll have to make a 3 hour drive each way to get that, and that's something I will worry about after the car is mechanically sound.

I am not in a position to pull or tear down the motor, but I will get some help with that if necessary. Can you guys give me any other help for now with the questions I posted?

Injuneer

As far as the tune, the tuners typically have a questionaire that you fill out. If the lift you quoted is the gross (valve) lift with 1.6X rockers, the tuner has to be told that. The pcmforless questionaire asks for "LIFT (max valve)".

You have to know what head gasket thickness was used to calculate the static compression ratio.

TitoPR221

First get the specific stroker-build information (actual stroke, top of piston distance to deck, piston dish cc, etc). Valve lift, top of piston height, head milling, block decking and piston top features also influence the gasket specifications. This is assuming the problem is a blown gasket. There is not enough information to confirm that the problem is a blown gasket.

ACE1252

Put a cooling system pressure tester on it to see if it will hold pressure.

Wouldn't the Felpro 1074 head gaskets work for him?

'97's had tty head bolts...I think(but your 383 may not). I used ARP head bolts on mine when I put it back together.

ChrisLS1Bird

Just discovered that the car has ARP head bolts already.

Engine was built 7 years ago and probably only has 200 miles on it (180 of which was accrued during one highway trip). It has an Eagle 4340 3.75 stroke crank and JE 16cc dished pistons (.030 over). All I have is an invoice from the builder (revolutionary performance). No data on "top of piston distance to deck," "top of piston height," or specific info on the exact amount of head milling or block decking.

I understand that we can get very very scientific with this. Will Felpro 1074s be appropriate? Are those the right bore (4.125")?

http://www.jegs.com/i/Fel+Pro/375/1074/10002/-1

I am waiting for a response from AI regarding the head gaskets and cam specs in conjunction with the 1.6 RRs.

PWR SHFT

revolutionary performance used to be a supporting vender but i believe they went out of business. Go to AutoZone or the like and rent a coolant pressure tester. That will tell you if it is a headgasket or atleast an issue witht he cooling system somewhere. Know for sure before throwing money at it and replacing parts.

TeeTopZ

FYI, if your engine is .030 over, you have a 4.030 bore. The 4.125 bore is the stock bore from a 400 sbc

ChrisLS1Bird

Coolant pressure tester...didn't know they had those. I was going to put the hours in to do a compression check instead.

AI recommended the Impala head gaskets, but I'm not sure they recalled that I said I had a 383. Those Impala gaskets are listed at 4.000 bore, but maybe that is not accurate. Surely someone makes 4.030 bore head gaskets. Do I have to get 4.125s or 4.000s and just not worry about the difference?

ACE1252

If I'm not mistaken, the stock LT1 head gaskets are 4.125" and I think the 1074's are thinner than the impala gaskets....however best to confirm that information. I'll do some looking around.

I forgot to mention that I used 1074's when putting mine back together. I was concerned when I put the 1074's on my block. They were not the same size as the bore. I compared them to the Chevy one's I pulled off and they had the same diameter bore.

ACE1252

Bingo...here is the stock gasket. 4.125" bore.
http://www.summitracing.com/parts/NAL-10168457/

Here is the Fel-Pro one(I think this is it...someone back me up on it...)....
http://www.summitracing.com/parts/FEL-1074/

PWR SHFT

Yup. Connect it to the filler neck on the radiator. Take the cap off, put the pressure tester on, and pump it up. Very easy.

Bersaglieri

Sounds like you need to find someone who knows what they are doing. You're making alot of assumptions with a very high performance motor. Not to be a jerk, but you're around the 3th grade level of engine knowledge and you should be in Jr. High to work on this motor.

You need to figure out the problem. You must realize it may require pulling the motor, tearing it down, and having a someone/engine builder go through and check and/or blueprint everything just to know what you're dealing with.

Does it really have a blown gasket, what's the compression ratio based on the actual head CC's, piston CC's, bore, gasket bore/thickness, stroke, etc. Dished pistons do not sound right on a solid roller build. What springs are on there, do they still have good spring pressures [important for solid roller], how many actual miles are on this motor, 200 sounds low for 7 years and if it make track passes then it's older than it seems. What rockers? What lifters? What lobe lift on the camshaft [yes it needs figured out with 1.6 rockers if that's what you have]. What LSA on the cam? You need that info for a tune at the very least. Does it already have a tune or dyno tune? Is it OBDII or converted to OBDI? What's the oil pressure? What oil is needed for the bearing clearance? The list goes on and on.

You should not be running a stock gasket on this build. This is why you need to know where the compression is/needs to be.

I don't want to discourage you, but you've got a long way to go before just driving this puppy around. You inherited a project car and you need to learn alot to not destroy this thing.

Was the previous owner a member here? Does AI or anyone else have info on the build that you could draw information from?

-Dustin-