Slant Six Forum :: Super Six Exhaust Manifold Question

... 6 into 2 headers? Fellas I raced slant/6's for 5 years on oval tracks around Michigan. I buzzed my first 234 ci Slant at 7000 rpms every night for 30 to 50 laps. We tried some of the trickest wierdest ideas on the planet to keep up with MIX & MATCH Chubby 306 ci inlines and 309ci Fords.
Oh Yah, I did IT!
The 6 into 2 (LONG pipes) works better than stock from 2400 rpms up to 6800 when the head just quits flowing.

Sweet working Stock Street exhaust?

STOCK Cast iron exhaust with the outlet OPENED up to 2.375" ID. Take this size into the casting, at least 2 inches.
Notice you will not be boring at a 90 degree angle to the stock flange. Meaning to accomplish the 2.375" to a 2" to 2 1/2" depth follow the casting of the manifold below where it mates to the carb. When it exits the manifold you will notice the straight line of this flow will not be parallel to the derectional flow of the stock flange. This off-angle will net you a 2 1/4" ID outlet. Hook up and carry THAT 2 1/4" ID all the way through a smooth flowing muffler to the tailpipe tip...

Author:	quikdrive [ Tue Aug 23, 2011 2:26 pm ]
Post subject:	Super Six Exhaust Manifold Question
I have been reading a few things that seem to contradict one another and wanted to try and get some clarification. Is there no difference (from a performance standpoint) between the Super Six exhaust manifold compared to one off of an early A body (66 dart)? I understand that there might be some casting differences w/ the support ribs or the choke pocket but it seems that the outlet diameter is the same. I am just trying to figure out if it worth even buying a super six exhaust manifold or just redoing my exhaust to a larger dia. Thanks Neil

Author:	raPoM [ Tue Aug 23, 2011 2:30 pm ]
Post subject:
All slant six exa manifolds outlets are the same. Only diff is the choke pockets,and "newer" casting have more ribs for durability. Jared

Author:	Doc [ Tue Aug 23, 2011 2:30 pm ]
Post subject:
No performance difference. With the exception of the Hyper-Pak exhaust manifolds... the passages and outlet size is the same on all factory SL6 exhaust manifolds. DD

Author:	quikdrive [ Tue Aug 23, 2011 2:36 pm ]
Post subject:
Thanks guys! Will save myself some money then. r/ Neil

Author:	raPoM [ Tue Aug 23, 2011 2:48 pm ]
Post subject:
Hahaha Doug, I think we both said it at the same time Neil- Good idea,I would just gasket match it,and clean it up and call it good. Jared

Slant Six Forum https://slantsix.org/forum/

Super Six Exhaust Manifold Question https://slantsix.org/forum/viewtopic.php?t=46066	Page 1 of 2

Author:	Aggressive Ted [ Tue Aug 23, 2011 3:28 pm ]
Post subject:
If you go with a 2.25" exhaust flange and pipe you can shave/grind off the inside of the cast iron exhaust manifold to match. It takes a few hours to do but will improve the flow, enough to feel the difference. I went up about 5" into the manifold @ 2.25". I am cheap and thought why not try it. I am gald I did..... The next step would be to buy one of Doc's manifolds (The "Dutra Duals" setup) so you can double the flow.

Author:	raPoM [ Tue Aug 23, 2011 5:58 pm ]
Post subject:
Ted- Good tip. When I did the SS swap on my first car (70 dart) I had my machinist friend open the manifold up on his lathe to 2 1/4 and it was a VERY big seat of the pants difference,and that was with the stock exhaus pipe What did you use to open your manifold up? Die grinder?

Author:	olafla [ Tue Aug 23, 2011 7:02 pm ]
Post subject:
These quotes are from an early thread, I think it was posted by someone named terry, forgive me if credit is placed incorrectly here... Quote: ... 6 into 2 headers? Fellas I raced slant/6's for 5 years on oval tracks around Michigan. I buzzed my first 234 ci Slant at 7000 rpms every night for 30 to 50 laps. We tried some of the trickest wierdest ideas on the planet to keep up with MIX & MATCH Chubby 306 ci inlines and 309ci Fords. Oh Yah, I did IT! The 6 into 2 (LONG pipes) works better than stock from 2400 rpms up to 6800 when the head just quits flowing. Sweet working Stock Street exhaust? STOCK Cast iron exhaust with the outlet OPENED up to 2.375" ID. Take this size into the casting, at least 2 inches. Notice you will not be boring at a 90 degree angle to the stock flange. Meaning to accomplish the 2.375" to a 2" to 2 1/2" depth follow the casting of the manifold below where it mates to the carb. When it exits the manifold you will notice the straight line of this flow will not be parallel to the derectional flow of the stock flange. This off-angle will net you a 2 1/4" ID outlet. Hook up and carry THAT 2 1/4" ID all the way through a smooth flowing muffler to the tailpipe tip... Re. differences in manifold castings: Some later manifolds came with provision for an O2 sensor. Olaf.

Author:	Aggressive Ted [ Wed Aug 24, 2011 9:34 pm ]
Post subject:
Jared, Yes, die grinder and some long shank cutters.

Author:	raPoM [ Wed Aug 24, 2011 10:05 pm ]
Post subject:
Ted, Thanks,I think thats what I will do this time,machinist friend lives in Utah...too bad, he was a good friend to have Did you use a gasket for the outline? If so where do you get your gaskets? Thanks Jared

Author:	Jeb [ Thu Aug 25, 2011 4:33 am ]
Post subject:
Get him to remachine the outlet flange itself and put in two new studs. That can be a hard one to seal up if it's not flat.

Author:	Aggressive Ted [ Thu Aug 25, 2011 9:04 am ]
Post subject:

Author:	Rug_Trucker [ Fri Aug 26, 2011 9:40 am ]
Post subject:
The exhaust manifold is some really hard stuff! Harder than head material. If I do one in the future I will send it to the machine shop.

Author:	USAJon [ Sat Aug 27, 2011 12:19 pm ]
Post subject:
used headers $175 delivered mounting Hooker washers FREE from Holley Corp. (nice salesman) duel exhaust tubing eBay local pick up new. w/clamps hangers $63 two thrush glasspacks $56 delivered

Page 1 of 2	All times are UTC-08:00
Powered by phpBB® Forum Software © phpBB Limited https://www.phpbb.com/

Author:	raPoM [ Sat Aug 27, 2011 12:31 pm ]
Post subject:
Quote: used headers $175 delivered mounting Hooker washers FREE from Holley Corp. (nice salesman) duel exhaust tubing eBay local pick up new. w/clamps hangers $63 two thrush glasspacks $56 delivered Cool,but what does that have to do with the stock manifold?