Blue Thunder Install this weekend

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Omie01

Well-known member
Joined
Oct 4, 2014
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Location
Minnesota, USA
My Car
1972 H code fastback Boss 351 clone
I am going to be installing my new Blue Thunder intake this weekend, and I was just wondering. I got the SCE gaskets for the port surface and rubber China Wall gaskets. Last year I used a little Black Permatex to seal the ports, but I was told to use Edelbrock Gasgacinch. Has anybody used The Gasgacinch for their intake? I found out the hard way last year that the SCE gaskets do not have the holes for the pins in the heads, I had to hurry up and punch holes while the Permatex was setting up. But now my gaskets look like they have wetness stains around the ports from the Permatex, so I want to try something different that wont stain or deteriorate the gaskets. The first set of gaskets I used were the edelbrock paper gaskets, and the bottom lip of the ports split on me and started sucking oil into the ports. The SCE gaskets are working well so I'm going to use another set for this intake.

 
I am going to be installing my new Blue Thunder intake this weekend, and I was just wondering. I got the SCE gaskets for the port surface and rubber China Wall gaskets. Last year I used a little Black Permatex to seal the ports, but I was told to use Edelbrock Gasgacinch. Has anybody used The Gasgacinch for their intake? I found out the hard way last year that the SCE gaskets do not have the holes for the pins in the heads, I had to hurry up and punch holes while the Permatex was setting up. But now my gaskets look like they have wetness stains around the ports from the Permatex, so I want to try something different that won't stain or deteriorate the gaskets. The first set of gaskets I used were the edelbrock paper gaskets, and the bottom lip of the ports split on me and started sucking oil into the ports. The SCE gaskets are working well so I'm going to use another set for this intake.
 I can only comment on my experience with a factory 4V intake reseal. When my engine was rebuilt, they used the rubber end seals, which subsequently leaked, so I had to redo it myself. I used a FelPro gaskets valley pan set with Permatex 2 gasket maker around the ports as RTV silicone does NOT stand up to gasoline. I then sealed the ends with "The Right Stuff". Expensive, but the best product for the job. The result is I have zero leaks, oil or vacuum.

If you can, post a pic of the Blue Thunder intake.

Thanks and hope this helps you.

Geoff.

 
I think it says on the permatex to not use if in direct contact with gas. Yes I always use Gasgacinch and just the metal turkey pan (no paper gasket) for intake. I just wish I know how to pronounce Gasgacinch......

 
I think it says on the permatex to not use if in direct contact with gas.  Yes I always use Gasgacinch and just the metal turkey pan (no paper gasket) for intake. I just wish I know how to pronounce Gasgacinch......
 Yes, Permatex RTV is not, but the Permatex 2 Form-a-gasket say it can be used anywhere. It is non-hardening as well. I've had no issues with it. BUT if I need to do an iintake manifold again, I'll look for the Gasacinch or whatever it is from Edlebrock, which was obviously made for the job.

 
Gasgacinch is used to hold the gasket in place while installing the manifold, it is still up to the gasket to provide the seal.

+1 on the Right Stuff, it's the only thing I use for these types of installations, where it is used instead of gaskets, including differential covers.

Remember, the aluminum manifold and iron heads have different expansion characteristics, so there will always be some movement at the manifold/gasket interface.

And, use all-thread, studs, or bolts with the heads cut off in the 4 center holes to provide help in centering and aligning the manifold squarely. If you use studs you can leave them in place, remove the other two types and install the correct bolts.

Finger tighten all the bolts in the recommended tightening pattern and then at least two torquing sequences, three is better.

 
I have a set of cut of bolts for the 4 middle bolts for alignment from the first engine I built, so I will be using those. I have used the rubber end gaskets each time with the permatex ultra black gasket maker and they have worked every time. My first problem was with the fel pro/edelbrock gaskets. They actually split on the bottom. The SCE gaskets have more meat to them. I have a turkey pan too, but have never cared much for them. Maybe I should take another stab at using it.

 
















Here it is all done. The first pic is the Air-Gap before removal. 2nd and third pics are the Blue Thunder before install. 4th pic is the engine prepped for install. 5th and 6th pic are the Blue Thunder and Air-Gap side by side for comparison. I did port match the Air-Gap as much as I was comfortable doing. Unfortunately there was just not enough meat to port match to 4v size. 7th and 8th pic are obviously the Blue Thunder installed, the engine is running during the pic. Vacuum is perfect, idles just as good as the Air-Gap, but I can't take it for a test drive until May. They salt the roads here in Minnesota so I can't drive it until the roads are clean and dry!! I didn't run into any problems during install other than the valve covers had to come off for clearance, and I did have to take the distributor out. Then one of the posts on the coil stripped out when I was re-connecting the wires, but that had nothing to do with the intake. I used the SCE gaskets, with the rubber China wall gaskets. You can use ARP Cleveland intake bolts, but the Blue Thunder comes with one bolt for the 3rd port on the passenger side, it is really long. I had to get different bolts for the Air-gap, it won't use regular Cleveland intake bolts. I just hope the upgrade is worth it. I'm sure I won't regret it!! It does seem to idle a little smoother but that could be in my head. OH, and the Ram Air air cleaner still will NOT fit under the hood with this intake. I was hoping it would!!

how to upload photos to internet

 
Yes, I use it to run the engine and still be able to tune the carburetor. In the spring we get a lot of dandelion floaties and other stuff in the air, it helps keep crap out of the engine while I tune it.

 
















Here it is all done. The first pic is the Air-Gap before removal. 2nd and third pics are the Blue Thunder before install. 4th pic is the engine prepped for install. 5th and 6th pic are the Blue Thunder and Air-Gap side by side for comparison. I did port match the Air-Gap as much as I was comfortable doing. Unfortunately there was just not enough meat to port match to 4v size. 7th and 8th pic are obviously the Blue Thunder installed, the engine is running during the pic. Vacuum is perfect, idles just as good as the Air-Gap, but I can't take it for a test drive until May. They salt the roads here in Minnesota so I can't drive it until the roads are clean and dry!! I didn't run into any problems during install other than the valve covers had to come off for clearance, and I did have to take the distributor out. Then one of the posts on the coil stripped out when I was re-connecting the wires, but that had nothing to do with the intake. I used the SCE gaskets, with the rubber China wall gaskets. You can use ARP Cleveland intake bolts, but the Blue Thunder comes with one bolt for the 3rd port on the passenger side, it is really long. I had to get different bolts for the Air-gap, it won't use regular Cleveland intake bolts. I just hope the upgrade is worth it. I'm sure I won't regret it!! It does seem to idle a little smoother but that could be in my head. OH, and the Ram Air air cleaner still will NOT fit under the hood with this intake. I was hoping it would!!

how to upload photos to internet
Must be the motor mount differences in the 73 or carb height differences.  I was able to fit the Ram Air with the Blue Thunder manifold

 
I contacted Permatex technical services to ask advice on which product SHOULD be used on the installation of an intake manifold with valley pan and paper gaskets as in the Fel-Pro type.

Quote: Permatex recommends High Tack Spray-a-Gasket (item # 80064). It should work very well for your application. Spray both sides of the intake manifold gasket and continue to the placement of the intake manifold on top of them. End quote.

 The tech did not confirm my question about Permatex 2, but only offered the above. I may contact him again for more information on Permatex 2. I and other engine guys I know have used this without issue as it is non-hardening, so it will move with expansion and contraction and not break the seal. Another Permatex product that was recommended to me was the Aircraft Grade gasket sealer.

Geoff.

Update on Permatex 2.

The tech say that both will do the job, but the High Tack Spray-a-Gasket has an improved formula and therefore better suited for manifold installation.

That's all I got from them. Pretty vague, but better info than nothing.

 
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Were you running a different intake before the BT? What is the biggest difference you can feel? Bottom end torque, mid-range pull, or top end RPM's?

 
Last fall I changed the stock cast iron clever intake that's in the wifes 67. Made a Big difference with that off the line feel. Even with the 3.70 gears before it was a bit sluggish with the cast. I just need too retune the Holley to fix the stumble it now has, but that's going to wait for spring. Been running a BT on my 72 for years. I just waited so long on the 67 because I wasn't real sure if the hood would clear the air cleaner. Its close, but its ok.

 
Were you running a different intake before the BT? What is the biggest difference you can feel? Bottom end torque, mid-range pull, or top end RPM's?
I was running a Performer b4 the BT. It helped in all 3 aspects, it's just better in every way. As far as I am concerned, it was like a night and day difference. Feels like a different car. I think you will be really happy.

I also used the Gasgachinch to hold the intake gaskets in place & I used the Right Stuff only for the valleys. Worked great.

 
Did you block the exhaust crossover channel in the manifold?

Last time i used the gasket to block the crossover the gasket eventually broke there after a few months of use. I wonder whats the best way to clock the crossover?

Sent from my SAMSUNG-SM-G930A using Tapatalk

 
The last time I had the heads off my Cleveland I used the gaskets without the heat passage hole, not realising they won't hold up. When I took it apart they were burned thru. This time I have cut pieces of aluminium bar, filed to fit & driven them into the heat passages on the intake side of the heads. I used a very small amount of sealer too. But then I scored a s/h RPM Air Gap to run instead of the Torker I was going to use so I needn't have bothered! Fire up estimated in 2-3 weeks.

 
I did not block the exhaust cross over, I removed that part of the gasket, But I am running the block off plate on top of the intake as my current carb has no choke. Will there be an issue having the exhaust ports functional?

 
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