Gen 4 heads on a Gen 5 block
 

I know this has been kicked around a little before, but can someone show some pics of both a gen 4 head surface and a gev 5 block surface, and where the potential leak areas are? Someone out there has to have some spare parts to take some pics of.

Re: Gen 4 heads on a Gen 5 block
 

Dennis Moore's BBC Marine Hi-Perf. book covers that all nicely with pics. Coolant leaks into the lifter valley. --- Jer

Re: Gen 4 heads on a Gen 5 block
 

Thanks, talked to TEAQUE today, and they first said sure with the right gaskets. But he went out back and talked to the mechanics and they said no way, it will definately not work. Now I have to change the whole motor..............

Re: Gen 4 heads on a Gen 5 block
 

gen 4 heads can be installed on a gen 5 or 6 block , use felpro# 1037 for 4.250 bore & 1047 for 4.500

Re: Gen 4 heads on a Gen 5 block
 

You know this question is coming, have you used these successfully? It would sure make things easier for me.

Re: Gen 4 heads on a Gen 5 block
 

SPANKER i wouldn't pull your tale on something like this ! if you need more info. email me and i will give you my phone ## :cool:

Re: Gen 4 heads on a Gen 5 block
 

I had a situation where I was going the other way around... I.E. Gen VI heads on a Mark IV block. I called the tech support at both Fel Pro ( Federal Mogul ) and Cometic... Cometic spent a great deal of time with me ( they were great ) in the end, they did not have a gasket recommendation... Fel Pro did recommend the 1037 / 1047 ( depending on std. bore vs overbore ) and stated that they have had good results either way, I.E. mark IV 's on gen 5 and 6 and vice versa. I upgraded my Mark IV ( 454 / 365 hp magnums ) to be identical to the HP-500...and topped it off with Gen VI heads. I had water problems in the oil. Blamed the heads at 1st. It turned out to be reversion. I pressure checked the head/block cooling system and the pressure was fine. All of that said, I am switching back to Mark IV
heads... My Gen VI heads ( rectangular port ) are going to be up for sale this spring.

Re: Gen 4 heads on a Gen 5 block
 

Yes, with the right head gaskets you can put Gen IV heads on a Gen V or VI block. Wrong head gaskets you will have cooling problems. I know I did till I got the right head gaskets. I also had problems finding the right push rods.

Re: Gen 4 heads on a Gen 5 block
 

Head gaskets to put Gen IV heads on a Gen V or VI block. Fel-Pro Marine, Gasket# 17048

Re: Gen 4 heads on a Gen 5 block
 

The 17048 is not listed for a 454 bore its for a 502 bore. But it still is not listed for a gen 4 head swap. But the 1037 does look like the right one. It's listed for all years.