My son has been working on this for a while and we just got it to the dyno for some initial first time tuning. Turns out the old 8 inch 'loose' 4500 RPM converter in the C4 trans barely lets the turbos start working but that's another mod to be done later...

351W with twin turbos, 42lb injectors, Pro M blow thru air meter, A1000 fuel pump and Paxton regulator.

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If you watch the video very closely, you can see when the exhaust header gasket blows by the heat coming up on the driver side over the intake manifold. We used these 'dead soft' aluminum two layer gaskets... Very frustrating...

Headers are hand made using a 3/8 BBK flange (cut off old header tubes - solid flange - not cut between ports) with stainless 1 7/8 pipe to the turbo flange. We had the flange milled flat after all work/welding was done. AFR 185 cylinder heads.

We'd like to change these header gaskets just 'one more time' because it is a PITA to do!

We're looking for the best gasket solution here to fix this 'once and done'.

Any suggestions!

 

Sounds good! Have you tried the high temp orange silicon to help?

 

Pics, Pics! Video doesnt show the details of how you built it. I want to do twins on my old F-100 and I am constantly gathering info here.

Benji

 

I just found 'REMFLEX" header gaskets as an option. Listed here by one of the authorized advertisers.

My two concerns here are:

1. Gaskets must withstand the heat

2. Gaskets must withstand the pressures induced by the turbo system

Of course there is the third and most important concern... that they don't blow out!

Any one tried these and have success?

 

I had the same issue on my last build and found high temp rtv to work best. I got it all over the place but if it keeps me from constantly changing gaskets. I can deal with the mess. Plus the tube has more than one set of gaskets, so it is more cheaper .

 

Are you using a gasket in conjunction with the high temp silicone or just the silicone between the head (AFR aluminum in this case with stainless header flange)?

 

Just use the orange silicone. Put it on both mating surfaces, let it sit for a bit and then slap her together. It doesn't need to go on thick at all. You should have no mess if done correctly.

 

I agree with the high temp RTV... I have used it many times and it works much better than gaskets.

 

My flanges were too low and did not let the flange sit flat on the head. I had to massage the flange to get the header to clamp down on the gasket.

Some picture would be cool too. There are no many around with shock towers and 351 turbos. What turbos? How much power on the dyno?

 

As long as both mating surfaces are as flat as can be and clean, you shouldn't have any problems with the orange cooper RTV. The stuff will last you till you have to take the headers off again, used it on my street coupe and never had a problem.

 

I guess I'm a little concerned about no gasket... But if it works and is a 'once and done' solution, I can go for that!

HP got up to 418 but if you look at the dyno graph you can see it is a steady increase in both HP and torque. The shop owner says the torque converter is too loose (4500 stall speed 8 inch converter) and the engine is never really seeing enough load to really use the turbos yet. We also need to get some air charge cooling on it as the timing had to be taken way out with the very hot charge going in. He also said we need bigger injectors as the fuel wanted to go lean.

He recommended methanol injection to solve both the air charge cooling and supplementing the injector size. He seems to think it will be well over 500 if we change the converter and add the methanol injection. We'll see.

Headers are one off's made from BBK header flanges and 1 7/8 stainless pipe tig welded routed straight forward to the turbo flanges.