Improved coolant flow to cyl 2 & 3 exhaust valves

[tekenaar]

Originally e-mailed to me by "RallyBob" Legere I have found that by simply adding a couple holes to the stock head gasket, I can lower the exhaust temps of #2 and #3 by about 150 degrees. I do this to all my Opel head gaskets, matter-of-factly. I cut two 3/8" holes at this area only. To locate these holes, lay the gasket on the head, and tap the gasket with a soft hammer right at the triangular-shaped water passage holes on either side of the head bolt hole beneath the center exhaust ports. Then in the center of these indentations you just made in the gasket, punch out the aforementioned 3/8" holes. I use a gasket punch.

[RallyBob]

Sorry guys, didn't think it was a big deal. Old news to me. It was Otto's idea to post it as a tip.

Bob

[soybean]

Originally Posted by Originally e-mailed to me by "RallyBob" Legere I have found that by simply adding a couple holes to the stock head gasket, I can lower the exhaust temps of #2 and #3 by about 150 degrees. I do this to all my Opel head gaskets, matter-of-factly. I cut two 3/8" holes at this area only. To locate these holes, lay the gasket on the head, and tap the gasket with a soft hammer right at the triangular-shaped water passage holes on either side of the head bolt hole beneath the center exhaust ports. Then in the center of these indentations you just made in the gasket, punch out the aforementioned 3/8" holes. I use a gasket punch. Otto

Otto, I have a question. I pulled the cylinder head and was going to try what you had posted for improved coolant flow. In the pictures I have enclosed there are several coolant passages that are compressed. Would it be of any benefit to open those up as well? The block has the openings.Thank you, Jarrell

[tekenaar]

Originally Posted by soybean Quote: . . . Otto, I have a question. I pulled the cylinder head and was going to try what you had posted for improved coolant flow. In the pictures I have enclosed there are several coolant passages that are compressed. Would it be of any benefit to open those up as well? The block has the openings.Thank you, Jarrell

Jarrell,
While it wouldn't hurt, the extra effort wouldn't improve things much beyond the two recommended holes, IMO, at least not in relation to the extra work involved. More chances for something to go "not quite right" with cutting the additional holes, too!

The biggest "hot spot" in the CIH head is, of course, the cylinders 2 and 3 junction because you have two exhaust valves right next to each other. Lowering exhaust gas temperature in this area results in the best cylinder-to-cylinder head temperature stabilization, which is the specific purpose of the extra coolant holes here, adjacent to #2 and #3 exhaust valves.

Of all the cracked heads I've seen, the great majority were in the #3 combustion chamber, typically cracked at the narrowest junction of the intake and exhaust valve seats.

[Travis]

Originally Posted by soybean Would it be of any benefit to open those up as well? The block has the openings.Thank you, Jarrell

This is common on the aftermarket head gaskets out of Europe. Here's one from Risse. I can't comment on it's effectiveness however.

-Travis

[calvin]

Man it would be almost worth the effort to pull the head to do this even though I only have 100 miles on the engine . I wish I knew that one earlier too.

I do have a question though about this. Do the 2 liter head gaskets that OGTS sells have more holes open than the stock 1.9 gaskets?

[GTJIM]

The extra holes would need to be of the correct size to carefully meter the water flow up from the block and through the head passages. Too much water directed up through the front of the head could shut off and "stagnate" the water in the rear of the head - that is why the stock set up has the large water hole at the rear - to promote water flow forward through the head.

That being said, opening up the water flow up past the spark plugs will help cool them and also allow any air/steam that is trapped below the gasket to be purged out of the system - looks like we will have to unlimber the 6mm and 8mm wad punches ........

The Risse gasket pic uploaded by Travis (thanks!) will give a guide to where to punch the holes - I think they know a bit about hi-perf CIH Opel motors ....

[nobody]

Calvin in a word the answer to whether the OGTS head gaskets have these holes the answer is no if you look back in the 2.0 thread I believe I showed them all and none had holes like Otto mentions. Sorry. That is a very good point Travis but I have an early and late model risse and they do not have the holes you mentioned. they are exatly like a felpro.

[Travis]

Originally Posted by nobody That is a very good point Travis but I have an early and late model risse and they do not have the holes you mentioned. they are exatly like a felpro.

Risse also sells them without the extra holes. It all depends on what you order...

-Travis

[soybean]

I belive when I put it back together, I will follow the pattern of the Risse gasket that Travis posted. I'm going to practice on the old gasket first though. I won't know the results for about a month until I get everything back on the car. I had been having a problem with overheating even though the engine was flushed. I think I am going to put a petcock on the thermostat housing like RallyeBob suggested to help bleed air out of the system as well. What the heck, can't hurt. Jarrell

[soybean]

I finished up cleaning up the head to put it all back together and this is what I found out. The Risse gasket has holes that wouldn't be needed. In the attached thumbnails, I have the holes that are existing on the felpro gasket. The old gasket on the head and the only places that new ones could be added. That is the question again? Would it be of any help or leave it stock, or like GtJim and RallyeBob suggested just the 2 holes between #2 and #3 exhaust valves. Thank you, Jarrell

[RallyBob]

I strongly suggest you only punch holes under the center exhaust ports as previously recommended. The greatest reason is because opening *all* the holes will mess up the flow characteristics of the coolant via turbulence. It is designed to flow from the front of the block to the rear of the block, drawing the heat away from the cylinders. Then it comes up through the rear of the head, pulling heat from the ports and combustion chambers before leaving the head via the thermostat housing. If you disrupt this pattern drastically, it can cause overheating problems, especially at lower rpms where the flow rate is slower.

HTH

Bob

[tekenaar]

Originally Posted by soybean I finished up cleaning up the head to put it all back together and this is what I found out. The Risse gasket has holes that wouldn't be needed. In the attached thumbnails, I have the holes that are existing on the felpro gasket. The old gasket on the head and the only places that new ones could be added. That is the question again? Would it be of any help or leave it stock, or like GtJim and RallyeBob suggested just the 2 holes between #2 and #3 exhaust valves. Thank you, Jarrell

As Bob said, only #2 and #3 holes closest to the junction of the cylinders should be opened up.

[jeff denton]

Well, jeez, that was simple enough! It didn't occur to me to scrutinize the head gasket and compare it to the head...
OK, I'm convinced. Everybody study this and punch a couple holes in your next head gasket!
Thanks, Bob (Keith?)!! Now the fuel grade thread can go back to its original topic

[nachi11744]

Hello,
IIRC, the ELRING head gasket for the CIH 2.0,2.2 and 2.4 have the holes punched out along all the cylinder block coolant ports on the intake/exhaust side, just like the Risse gasket.
Hope that helps.

[nachi11744]

Hello,
Pic of ELRING headgasket for Opel CIH engine.