Biggus

iTrader: (1)

I'm experiencing premature head gasket failure on a pair of warmed over 575 SCI's. The motors are basically stock with the exception of flat top pistons and roller cams (similar to the 500 EFI cam) and reprogrammed rev limiters to 5450 rpm. Boost has not been increased, stock pullies @ 4psi at 5400

We are running the Fel-Pro 1047 I believe. The firing rings are toasted badly and we've also got leaking water into the intake valley. Our engine builder is thinking that the increased compression of the flat top pistons is putting the motors right on the edge and there is some detonation because of the increased combustion chamber temps.

I've read the rave reviews of Cometic head gaskets. Would they really be up to the task in this situation? Would a pair of Whipple intercooler/intake manifolds be the answer?

Looking forward to your input.

Kurt

PatriYacht

It seems to me that the Fel-Pro should be ok for such low boost. If you are having detonation you should fix that before something serious happens. It's like the head gasket was sending a warning. I think intercoolers are a great idea. They will probably up your hp also. Detonation is a real hp killer.

Steve Zuckerman

Biggus,
I am running a 575 with an AZSM boost kit, Whipple intercooler and 3" blower pulley for 7lbs. of intercooled boost.
Running the Fel-Pros and 93 octane with no problems.
Who recurved your ECU (advance, EFI air fuel ratio, etc.)?
What octane are you running?
I have a friend running 575s with a Comp hydraulic roller, no
intercooler, Fel-Pros, 3.5" blower pulleys, AZSM ECU recurve, running 93 octane, and no problems either.
I would have AZSM take a look at your ECU and add the intercoolers.
Regards,
Steve

Biggus

iTrader: (1)

ECU's were reprogrammed by Arizona Speed & Marine.

Thanks for the replies.

bobl

I just refreshed a set of 575's for a customer. I wanted to use Cometics but he insisted on using Merc parts. So, I ordered a set from Merc... Lo and behold 2 pair of Cometics showed up! Looks like they upgraded them on the late 575's, 525's and 600's from looking at the part numbers.

Crazyhorse

Hi Kurt. Long time no see.
I'm running Felpro 17048 gaskets with no problems (8.9:1 with 7 lbs boost). My timing is at 32 degrees.
Make sure to follow the Felpro torque instuctions to the letter. Double-check the total advance under actual conditions, either on a dyno or on the water with a good timing light. Also, be wary of timing lights that pull the timing mark to the zero line (knob on the back) as these can infrequently give erroneous readings when being used on electronic ignition systems.
How's Tim's boat doing?

Kelly O

Came across this old thread searching for head gasket info. Trying to figure what my '03 motors have on them stock. For my late serial number engines ( OM900000 and up ) the Merc. part number is 27-811546A03. These are different number than the three previous serial number series for the 575 sci.
So anyone know what the updated Merc. gaskets were ? Could they have put Cometics in at factory ???

bobl

It appears that the latest 575's did come with the Cometics, based on the part numbers. The number you listed is for the Cometic.

mrhorsepower1

Kurt,
Give me a call if you need the gaskets or advice. Thanks!

Dean

Biggus

iTrader: (1)

Thanks Dean but this is a thread from almost two years ago.

We installed the Cometic head gaskets along with Whipple intercooler/intakes. Working very well on this 30 Mystique T/S.