Better head gasket for a 1500

[maddy]

I've put a turbo on my 79' 1500 midget, 9:1 pistons and the like. The head was rebuilt and resurfaced. The block was true on top. All studs and bolts are ARP, which I torqued at 55 lbs on the head. At 7 lbs boost I figure that I'm around 13:1 or 14:1 CR. I've blown 3 head gaskets so far, the last using copper wire around galleys. I'm hoping someone knows where I can find a better than Payne head gasket. The top of the block has recessed grooves around the cylinders which stops me from fabricating my own out of copper.
Thanks for the help!!!!

 

[Hap Waldrop]

Mark, I think you're pretty much stuck with that head gasket, 9 to 1 CR probably wasn't the way to go with forced induction. Have you straight edge checked the block and head?

The 1500 racers, what few they are, use a shorter compression height pistons and deck the block enough to get rid of the recessed area in the top of the block, then use a 1300 head gasket. I've built a few race 1500s using TR6 pistons which have a shorter compression height and require block decking, this would be a good way to get your engine back to say 8 to 1 CR and that way you can explore with higher boost levels, at 9 to 1, you going to run into these type issues with forced induction.

 

[Morris]

Without forced induction, I was routinely blowing Payen head gaskets at 9:1 compression. I sprayed the last head gasket I installed with Permatex Copper Seal, it has held steady for the past 3 years.

I would love to see some pics of your turbo set up.

 

[Hap Waldrop]

Without forced induction, I was routinely blowing Payen head gaskets at 9:1 compression. I sprayed the last head gasket I installed with Permatex Copper Seal, it has held steady for the past 3 years.

I would love to see some pics of your turbo set up.

I would also recommend Permatex Hi Tack spray sealer, I like it better than the copper spray, the copper spray has changed over the years and now seem to react with some of the black composite gaksets, I even use it on the copper gaksets on the 948s. I started trying the Hi Tack on the Turbo 1275 competition head gaskets to get more than one use out of them on the race cars since they were like $150-200 each, to keep them from stiicking and tearing when you remove them, it did a great job with that nad kept my 15.5 to 1 race engine sealed up as well.


Mark, what are you torqueing the head to with your ARP studs?

 

[maddy]

Without forced induction, I was routinely blowing Payen head gaskets at 9:1 compression. I sprayed the last head gasket I installed with Permatex Copper Seal, it has held steady for the past 3 years.

I would love to see some pics of your turbo set up.

I would also recommend Permatex Hi Tack spray sealer, I like it better than the copper spray, the copper spray has changed over the years and now seem to react with some of the black composite gaksets, I even use it on the copper gaksets on the 948s. I started trying the Hi Tack on the Turbo 1275 competition head gaskets to get more than one use out of them on the race cars since they were like $150-200 each, to keep them from stiicking and tearing when you remove them, it did a great job with that nad kept my 15.5 to 1 race engine sealed up as well.


Mark, what are you torqueing the head to with your ARP studs?

I torqued to 55 lbs the last go around with lots of ARP toqueing compound and smooth strokes on the wrench.

 

[Guest]

Hap, can't he just make one from a sheet of dead soft copper and not worry about the ring area? I would think he could get by like that.

 

[RonMacPherson]

Fel-Pro used to offer a high performance gasket set for the lbcs. Know they still offer one for the Tr6, maybe see if they have one for your engine.

 

[Morris]

I used a Fel-Pro gasket once. It blew pretty quickly, and took me days to scrape off.

 

[Hap Waldrop]

Hap, can't he just make one from a sheet of dead soft copper and not worry about the ring area? I would think he could get by like that.

No, I never seen anyone sucessfully use one of those solid copper gaskets, I had a buddy who raced a 1500 Spitfire, we fooled around at his shop one with one of those solid copper gakets on a 1500, we had to anneal it with torch, followed the instreuction to a tee, instlled torqued everyhting down fired the engine up and watch water pout out between the blcok and head. over the year at the race track the solid copper head gakset subject has came up more than once, the experience most folks had was simular to ours.

I think Mark's ordeal has to do amybe with the amount of boost he is running and his CR or either a deck on the block or the head that is not perfectly straight, that would be my guess anyway.

As mentioned most 1500 racers I know, don't use the 1500 gasket, but rather the deck the block flat and use the 1300 gaskets, and I can tell you this one firsthand if you deck the block on a 1500, say .020" or more then try to use the normal 1500 head gasket you are screwed for sure, not enough area for the gasket to properly squish in the recessed areas. Been there, done that, filled the crankcase up with water

 

[Scott_Hower]

Hap - can you o-ring a 1500 block to handle the boost?

 

[maddy]

I did some rather radical things to try solving the issue. Copper paint, copper tape, Indian Head shellac, re-torqueing…. I’m going to 7 lbs tomorrow! If after that, and if the same thing happens, it’s lower with the boost.

 

[maddy]

I used a Fel-Pro gasket once. It blew pretty quickly, and took me days to scrape off.

Fel-Pro and Payne are one in the same! Same marking on both. At least those that I've got.

 

[Hap Waldrop]

Hap - can you o-ring a 1500 block to handle the boost?

Well for Mark, that would not really be a option, because he would have to deck the block flat would would raise his compression ratio even more with his current pistons. Yes is could be done with if the bloc were decked in another application. I think a cool way to do a forced induction 1500 would be to use TR6 flat top pistons and deck the block until you come up with about 8.0 to 1, then Mark could really play with boost. Most 1500 racer, just deck the block flat, then use custom forged pistons and a 1300 head gasket, most of them with this set up have good sucess at CR as high as 14-15 to 1. I think Mark either has a head or block deck issue or the 7 pounds is too much boost at 9 to 1.

 

[Trevor Jessie]

Or... do you know someone that works at a CNC machine shop. You could have a plate made to decrease the CR. However, you would then have to be sure your valves could still open properly. You'd also then have to worry about two head gaskets... never mind it is more complicated than it's worth. :frown:

 

[Guest]

Hap - can you o-ring a 1500 block to handle the boost?

. I think a cool way to do a forced induction 1500 would be to use TR6 flat top pistons and deck the block until you come up with about 8.0 to 1, then Mark could really play with boost. I think Mark either has a head or block deck issue or the 7 pounds is too much boost at 9 to 1.

There is a guy in Dallas who turbos Ferraris w/ stock 11 to 1 pistons. He programs the injection for (lots) more fuel under boost to keep it cool and from comming apart. I want to say he goes as high as 11-15 psi, but I can't remeber.

You can boost high compression engines, you just need to have a VERY flexible and controlable fuel delivery system. The Z cars guys boost 9 to 1 motors all the time. Hyundai guys are doing it w/ 10.3 to 1 factory cast piston motors, usually in the 5-9 pound range with 5 being max on factory injection.

Using high comp pistons on a boosted motor supposedly does away with any turbo lag, but you really have to watch what you're doing. One mistake in programming and *POW*!

Haven't done it yet, but I got a BIG pile of turbos here.

Maddy, what are you using to get the juice to it?

 

[maddy]

I tried to blow the head gasket, without success! Ran it at 7 lbs boost to 6.5k rpms, no smoke, just power. Does it feel good! Hopefully, I’m good the summer…

 

[maddy]

I've got a Mitsubishi Talon sucking thru an SU HIF4. You can look here to see the "issues" I've been having
https://www.mgexperience.net/phorum/read.php?3,1291166
Funny thing is that the worst of it has been the head gasket!!!

Hap - can you o-ring a 1500 block to handle the boost?

. I think a cool way to do a forced induction 1500 would be to use TR6 flat top pistons and deck the block until you come up with about 8.0 to 1, then Mark could really play with boost. I think Mark either has a head or block deck issue or the 7 pounds is too much boost at 9 to 1.

There is a guy in Dallas who turbos Ferraris w/ stock 11 to 1 pistons. He programs the injection for (lots) more fuel under boost to keep it cool and from comming apart. I want to say he goes as high as 11-15 psi, but I can't remeber.

You can boost high compression engines, you just need to have a VERY flexible and controlable fuel delivery system. The Z cars guys boost 9 to 1 motors all the time. Hyundai guys are doing it w/ 10.3 to 1 factory cast piston motors, usually in the 5-9 pound range with 5 being max on factory injection.

Using high comp pistons on a boosted motor supposedly does away with any turbo lag, but you really have to watch what you're doing. One mistake in programming and *POW*!

Haven't done it yet, but I got a BIG pile of turbos here.

Maddy, what are you using to get the juice to it?

 

[Guest]

I tried to blow the head gasket, without success! Ran it at 7 lbs boost to 6.5k rpms, no smoke, just power. Does it feel good! Hopefully, I’m good the summer…

Let's see what she'll hold. :hammer: :wink:

:angel:

 

[Hap Waldrop]

Or... do you know someone that works at a CNC machine shop. You could have a plate made to decrease the CR. However, you would then have to be sure your valves could still open properly. You'd also then have to worry about two head gaskets... never mind it is more complicated than it's worth. :frown:

That would have to be a really thin plate and then would require 2 head gaskets (double trouble), as it doesn't take alot of material on block decking to draticly change CR. Cometic head gakset would be a good remedy if they made a MLS head gasket for the Triumph small 4cyls, but they do not, you can have them cusmtom made up to .060" thickness.

The deal with TR6 pistons in the 1500 is they have a lower compression height, to get to zero deck on a 1500, you have to wack the block like .250", but in a forced induction application, it would allow to taylor to CR with deck height.

 

[Guest]

Glad to see she's holding. I've read through (glanced at) the link you provided. There are a couple of things that I didn't see mentioned that will cause problems if left unchecked. I didn't see anything mentioning secondary enrichment under boost. Have you made a provision for that? From everything that I've read (not experienced first hand), once you get above 5#s, A/F ratio becomes a big concern. Something needs to be done to richening the mixture up to help compensate for the extra air leaning things out and the resulting detonation above that level. If secondary enrichment wasn't addressed, this may have contributed to your problem.


IIRC (from what I've read), that Mitsu turbo being used doesn't have the correct seal at the compressor for a draw through application. According to Corky Bell, w/o that it'll push fuel into the main housing and thin the oil which will burn up the turbo AND the engine. While that's not the casue of your immeadiate problem, unless it's sealed right it will be a problem in the future.

I mention these things only because I didn't see mention of them being addressed in the link. I would hate to see all of your hard work go *POOF*. I am by no means an expert in this area. I'm only going off of knowledge gained from others in the field. You may already know this, but as a friend, I feel compelled to makes sure. If I sound like a smart A$$, it's accidental (in this case).