tall deck exhaust
Thread Starter
Le Mans Master
Joined: Aug 2010
Posts: 8,519
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From: Bussey, IA
tall deck exhaust
Have a '68 Coupe that is getting a 427 tall deck. Does not have any exhaust at this point. Is TD exhaust the same as SD? In other words can I run standard headers on my engine? TIA 
Andy
Andy
Melting Slicks
Joined: Jan 2003
Posts: 3,030
Likes: 94
From: meraux LA
I'm running a set of Brodix alum heads on my 454 that have .5" raised exhaust ports. The headers I used are the hedman std . 454 headers. I did have to massage the #3 and #4 tubes for steering box and frame clearance.
Le Mans Master
Joined: Apr 2007
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From: Graceland in a Not Correctly Restored Stingray
The tall block is has a nominal deck height of 10.200" verses the standard's 9.800". ...which in the case of a short stroke such as the 427's begs the question, why? If it's about rod length, given you're most likely looking at custom slugs anyway you could just adjust the pin height for .250" or .400" long rods in a standard block (~1.7:1 or ~1.74:1 rod/stroke, respectively), avoiding unnecessary reciprocating inertia and weight. Just my $.02.
Melting Slicks
Joined: Feb 2006
Posts: 3,105
Likes: 96
From: Sunrise FL
The tall block is has a nominal deck height of 10.200" verses the standard's 9.800". ...which in the case of a short stroke such as the 427's begs the question, why? If it's about rod length, given you're most likely looking at custom slugs anyway you could just adjust the pin height for .250" or .400" long rods in a standard block (~1.7:1 or ~1.74:1 rod/stroke, respectively), avoiding unnecessary reciprocating inertia and weight. Just my $.02.
If that's the case there are spacers available that permit use of regular BB intakes too. There is info in the archives about truck BBs.
Last edited by mikem350; Mar 31, 2016 at 04:17 PM.
Thread Starter
Le Mans Master
Joined: Aug 2010
Posts: 8,519
Likes: 506
From: Bussey, IA
I believe the 572 td uses the same block as the 427 td. Would the modification have to at the head (do sd and td manifold/header mount the same, same bolt pattern and distance etc) or in the tube body ("dented" or adjusted for clearance or lengthened to drop low enough). Thanks
Thread Starter
Le Mans Master
Joined: Aug 2010
Posts: 8,519
Likes: 506
From: Bussey, IA
Do you have a picture of that and how much you had to "massage"? Had any issues from heat on the steering box?
Thread Starter
Le Mans Master
Joined: Aug 2010
Posts: 8,519
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From: Bussey, IA
Sounds like the OP wants to use the tall deck truck motor as is?? So what you are saying is the exhaust outlets on the head will move the headers up 0.4 inch, and out some due to the new angle.
If that's the case there are spacers available that permit use of regular BB intakes too. There is info in the archives about truck BBs.
If that's the case there are spacers available that permit use of regular BB intakes too. There is info in the archives about truck BBs.
I have an L88 hood, so I think I will be OK on height but not sure about the rest.
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Melting Slicks
Joined: Feb 2006
Posts: 3,105
Likes: 96
From: Sunrise FL
I installed Heddman headers on my 66 BB and had to dent the tubes at the box and I think the idler arm. No big deal, everybody with a bb does the same. In your case might have slightly more interference due to the extra width. Yes they will heat up the box...it does happen, but so do iron manifolds.
I bought the headers, fitted and dimpled as needed, and then had 'em Jet coated, which cuts down the heat. One or two plugs also were tricky, think I dimpled at the bend to get a wrench on them too.
I would be careful about intake selection, even with the L88 hood.
I bought the headers, fitted and dimpled as needed, and then had 'em Jet coated, which cuts down the heat. One or two plugs also were tricky, think I dimpled at the bend to get a wrench on them too.
I would be careful about intake selection, even with the L88 hood.
Last edited by mikem350; Apr 1, 2016 at 11:27 AM.
Thread Starter
Le Mans Master
Joined: Aug 2010
Posts: 8,519
Likes: 506
From: Bussey, IA
Do you have an idea of how much wider a td is than a sd? and any recommendations on the intake? I am all ears! Also, are M/T valve covers out of the question also for clearance sake?
Melting Slicks
Joined: Feb 2006
Posts: 3,105
Likes: 96
From: Sunrise FL
The 572 crate motor is a TD and dimensions are similar. Search the archives for this swap. You can also check the C2 forum, same chassis, but fiberglass is different.
Are you using the peanut heads?
Are you using the peanut heads?
Le Mans Master
Joined: Apr 2007
Posts: 7,353
Likes: 72
From: Graceland in a Not Correctly Restored Stingray
cos(45*) x 0.400" x 2