Overheating BBC 468 Pro Street Willy's Coupe

[In-Tech]

The gasket you have now is the wrong one!
The victor reinz 4918 and 4923
conversion gaskets (left and right) should solve the problem.

Yeah, sheesh, problem solved. If you need a higher hp gasket, cometic makes one to fix the problem too.

[rp930]

I would use the special gaskets for what appears to be a known issue. Why add one more variable to this? I am sure the water pump will pump an adequate amount of water. If Cometic has them, which I would verify with them directly, then I would probably use them. I am sure the Victor Reinz or Mahle if you can find them. You don't want to have to do this again.

It looks like they are available on Amazon and elsewhere.

[topradman]

The gasket you have now is the wrong one!
The victor reinz 4918 and 4923
conversion gaskets (left and right) should solve the problem.

Yeah, sheesh, problem solved. If you need a higher hp gasket, cometic makes one to fix the problem too.

Ok, here's what I am having Cometic do for this gasket ( see lower portion of attachment ). The distributor has been corrected and my local machinist is check the heads for good health. He is also going to throw in a multi-angle valve job on the intakes only to help get the atomized fuel into the chambers. I think this thing is going to work now! The valves were in good shape, springs and seals were clearly new and we decided to leave the valve sizes alone as this is not a race car, just a grumpy lil' Willys coupe. I am changing the 3 coolant ports on the lower edge that come up between the cylinders and down sizing to 5/16" instead of 1/2" - 1/2" & 5/8". I think this will encourage the coolant to go all the way back to the rear of the head and not stagnate so much in the middle of the block as well, especially the passenger side. Based on the temp readings, this should solve that problem. It should also improve the velocity in which the coolant moves through the engine since it will mostly be the old school gasket stratagey that had no coolant holes along the bottom edge. I was nervous to not direct at least some of the coolant up between the cylinders as this is close to the exhaust valve seats so that is why I am retaining those 3 passages, just making them smaller. It should be kind of a hybrid series/parallel flow result. I feel pretty good about this change. We will see!

I have done cooling systems on a lot of old style big blocks that would be of the Mark IV design with heads and block that matched and just have never had this much problem. That is why I lean towards that strategy.

Will hopefully get the heads back next week. Also have an air gap manifold coming to help encourage the carb to stay cooler, not only because of the air gap itself but no exhaust even enters the intake this way.

[rp930]

Looks like that will work just fine. I might have checked the quench and possibly used a thinner head gasket if it was me since you are using Cometics.

[topradman]

Looks like that will work just fine. I might have checked the quench and possibly used a thinner head gasket if it was me since you are using Cometics.

I just checked deck height and with the flat top 0.030 HP pistons we are in the hole 0.026". Cometic will make a recommendation I am sure but you are right, 0.040 would not be optimum. Thanks rp930!

[topradman]

Cometic gaskets are officially on order. The part numbers will be archived and they are H2193SPBG027S (driver side) H2193SPBH027S (passenger side). The last 2 digits are for gasket thickness so if you needed a 0.030 or 0.040, the last two would be "30" or "40" respectively. Thanks again to rp930 for the pointer on the gasket thickness. I have been so involved in the heating end of this engine, it completely slipped my mind to check deck height and was going to just go with the same thickness that we took off the car.

Should have some results here week after next!

[Keith Morganstein]

If it was me, I would just assemble the engine with the victor-reinz/mahle conversion head gaskets and re-test. From my perspective the engineers at victor-reinz have already figured out what works. Hopefully, the Cometic gaskets ordered will also cure the problem.

Once I've installed temp probes in a system, I leave them I until I'm satisfied the overheating issue has been solved.

[topradman]

If it was me, I would just assemble the engine with the victor-reinz/mahle conversion head gaskets and re-test. From my perspective the engineers at victor-reinz have already figured out what works. Hopefully, the Cometic gaskets ordered will also cure the problem.

Once I've installed temp probes in a system, I leave them I until I'm satisfied the overheating issue has been solved.

After careful consideration of all this, I opted to go with my own coolant port design and here is why. I feel like, with virtually nobody or very, very few people that seem to be "in the know" on this Mark IV/Gen V conversion there probably has been very, very little if any testing or research done that would make Victor/Reinz the only definitive choice. I feel like someone in their R&D or a couple of "somebodies" just studied the gaskets and came up with the 4918 and 4923 and it worked, simply by opening both back holes and making the bottom 3 the same size. I would be willing to wager there was actually no testing done on this. I cannot find an article that discusses solving this problem. I go to Jegs, Summit & Speedway motors and there is not definitive look up for this pair of gaskets, no option for "Conversion" gasket either. I go to Victor/Reinz Mahle online catalog and do a search and they will not come up using those numbers nor will they come up under any application I have tried to use for GenV block and no "Conversion" option either. Same with Felpro online catalog. Felpro just warns you not to do it.

Unless I am missing something in all of these searches? And I admit, I could have missed something.

Admittedly, there are the articles that suggest using these gaskets but no info on how they arrived at this decision. I haven't found any article along the order of "we contacted our friends at Victor/Reinz and they were happy to meet the challenge. After extensive testing of various flow designs they came up with the part number 4918 & 4923." You know what I mean?

That being said, I have the upmost faith in the quality of Cometic and their MLS gaskets. I have them on my 850 RWHP street Camaro and no problems. Multiple engine builders that I know personally swear by them for any high compression or high horsepower engines, especially boosted motors. So, that's why I went with Cometic and my own thoughts on gasket design, of course after studying parallel flow series flow gaskets by Felpro, Cometic and of course, considering the Victor/Reinz "conversion" gasket pair.

I had to remove the probes to do the engine disassemble.

I CAN SEE BBC GASKETS IN MY SLEEP NOW!

[rp930]

Cometic gaskets are officially on order. The part numbers will be archived and they are H2193SPBG027S (driver side) H2193SPBH027S (passenger side). The last 2 digits are for gasket thickness so if you needed a 0.030 or 0.040, the last two would be "30" or "40" respectively. Thanks again to rp930 for the pointer on the gasket thickness. I have been so involved in the heating end of this engine, it completely slipped my mind to check deck height and was going to just go with the same thickness that we took off the car.

Should have some results here week after next!

Happy to help. I used the .027 gasket on mine too. At least got the quench closer to right.

[rp930]

Any update?

[greg]

[topradman]

Any update?

Just got heads back from machine shop this afternoon. Should have some results to post next week.
Stay tuned. I did not start this thread to leave it hanging.

[midnightbluS10]

If it was me, I would just assemble the engine with the victor-reinz/mahle conversion head gaskets and re-test. From my perspective the engineers at victor-reinz have already figured out what works. Hopefully, the Cometic gaskets ordered will also cure the problem.

Once I've installed temp probes in a system, I leave them I until I'm satisfied the overheating issue has been solved.

After careful consideration of all this, I opted to go with my own coolant port design and here is why. I feel like, with virtually nobody or very, very few people that seem to be "in the know" on this Mark IV/Gen V conversion there probably has been very, very little if any testing or research done that would make Victor/Reinz the only definitive choice. I feel like someone in their R&D or a couple of "somebodies" just studied the gaskets and came up with the 4918 and 4923 and it worked, simply by opening both back holes and making the bottom 3 the same size. I would be willing to wager there was actually no testing done on this. I cannot find an article that discusses solving this problem. I go to Jegs, Summit & Speedway motors and there is not definitive look up for this pair of gaskets, no option for "Conversion" gasket either. I go to Victor/Reinz Mahle online catalog and do a search and they will not come up using those numbers nor will they come up under any application I have tried to use for GenV block and no "Conversion" option either. Same with Felpro online catalog. Felpro just warns you not to do it.

Unless I am missing something in all of these searches? And I admit, I could have missed something.

Admittedly, there are the articles that suggest using these gaskets but no info on how they arrived at this decision. I haven't found any article along the order of "we contacted our friends at Victor/Reinz and they were happy to meet the challenge. After extensive testing of various flow designs they came up with the part number 4918 & 4923." You know what I mean?

That being said, I have the upmost faith in the quality of Cometic and their MLS gaskets. I have them on my 850 RWHP street Camaro and no problems. Multiple engine builders that I know personally swear by them for any high compression or high horsepower engines, especially boosted motors. So, that's why I went with Cometic and my own thoughts on gasket design, of course after studying parallel flow series flow gaskets by Felpro, Cometic and of course, considering the Victor/Reinz "conversion" gasket pair.

I had to remove the probes to do the engine disassemble.

I CAN SEE BBC GASKETS IN MY SLEEP NOW!

Why would you assume they didn't do their jobs? What makes you think no one had this issue, researched the issue, documented it all, and found a fix? Because they didn't put it on an automotive forum or have it ran in any one of a number of mags? Because you couldn't find it? Is there anything else to support your theory that they did their jobs half as deductible with no evidence pointing towards that? You haven't even used the gaskets, yet you're already shitting in them. How do you know they have all these downsides?

[topradman]

If it was me, I would just assemble the engine with the victor-reinz/mahle conversion head gaskets and re-test. From my perspective the engineers at victor-reinz have already figured out what works. Hopefully, the Cometic gaskets ordered will also cure the problem.

Once I've installed temp probes in a system, I leave them I until I'm satisfied the overheating issue has been solved.

After careful consideration of all this, I opted to go with my own coolant port design and here is why. I feel like, with virtually nobody or very, very few people that seem to be "in the know" on this Mark IV/Gen V conversion there probably has been very, very little if any testing or research done that would make Victor/Reinz the only definitive choice. I feel like someone in their R&D or a couple of "somebodies" just studied the gaskets and came up with the 4918 and 4923 and it worked, simply by opening both back holes and making the bottom 3 the same size. I would be willing to wager there was actually no testing done on this. I cannot find an article that discusses solving this problem. I go to Jegs, Summit & Speedway motors and there is not definitive look up for this pair of gaskets, no option for "Conversion" gasket either. I go to Victor/Reinz Mahle online catalog and do a search and they will not come up using those numbers nor will they come up under any application I have tried to use for GenV block and no "Conversion" option either. Same with Felpro online catalog. Felpro just warns you not to do it.

Unless I am missing something in all of these searches? And I admit, I could have missed something.

Admittedly, there are the articles that suggest using these gaskets but no info on how they arrived at this decision. I haven't found any article along the order of "we contacted our friends at Victor/Reinz and they were happy to meet the challenge. After extensive testing of various flow designs they came up with the part number 4918 & 4923." You know what I mean?

That being said, I have the upmost faith in the quality of Cometic and their MLS gaskets. I have them on my 850 RWHP street Camaro and no problems. Multiple engine builders that I know personally swear by them for any high compression or high horsepower engines, especially boosted motors. So, that's why I went with Cometic and my own thoughts on gasket design, of course after studying parallel flow series flow gaskets by Felpro, Cometic and of course, considering the Victor/Reinz "conversion" gasket pair.

I had to remove the probes to do the engine disassemble.

I CAN SEE BBC GASKETS IN MY SLEEP NOW!

Why would you assume they didn't do their jobs? What makes you think no one had this issue, researched the issue, documented it all, and found a fix? Because they didn't put it on an automotive forum or have it ran in any one of a number of mags? Because you couldn't find it? Is there anything else to support your theory that they did their jobs half as deductible with no evidence pointing towards that? You haven't even used the gaskets, yet you're already shitting in them. How do you know they have all these downsides?

WTF???? I think you answered your own question. I didn't "assume they didn't do their jobs". I am not "shitting" on anything. Read the post. Can you show otherwise? Have you used the gaskets? RU a democrat troll?? Wow.

[rp930]

Topradman-

Wow is right. Please don't let that stop you from giving us an update.