How fast have you gone with exhaust manifolds?

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LXguy

LXguy

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Hey All

Doing the header procrastination thing, so inevitably, the alternative of just running some hp manifolds has come up.

Has anybody actually run them at the track? How fast did you go?

Thanks!

Steve
 
XE284 comp cams cam, .030 360 with factory dished pistons, Edlebrock Torquer II intake, a 850 holley carb that flows 1130 cfm's, factory iron heads that were bowl cut and blended with a gasket match with 1.88/1.60 stock valves. Fully adjustable valve train with 3/8 chrome moly pushrods, timing set at 35* total @ 2500 rpms.
 
That's pretty awesome!

Did you ever try it with headers and the same combination?

What kind of manifolds were they?
 
HI
I ran a 13.76 with stock manifolds on my 64 Dart Gt at Speed World in Az. for the first time out 103 & 13.76
 
LXguy said:
That's pretty awesome!

Did you ever try it with headers and the same combination?

What kind of manifolds were they?
Click to expand...

We used a set of shorty hedders which are on there now and it runs a best of 7.36 @ 95 mph 1/8. It also has a 4 ft. tube that connects to the shortys because of the fumes, this is just to get it past the drivers compartment, and not for any other reason.

As for the manifolds they were standard 360's.
 
13.2 @ 105 mph. This was done on Repop E70-14 Red Lines.

340, 4 Speed.


I would also like to note... This is down from the 11.78 @ 118 mph I was running with headers, 3" exhaust and slicks.
 
I think some of the FAST guys use the extrude honing process to kind of hog out and polish the manifolds. It's expensive, but supposedly it works pretty well. Might be worth a look if you really want to use your manifolds.

http://www.gethoned.com/process.html
 
Pretty awesome numbers, guys.

That site says Extrude Hone wants $675.00 to do a pair of exhaust manifolds!!!!

SHEESH!

Steve.
 
LXguy said:
That site says Extrude Hone wants $675.00 to do a pair of exhaust manifolds!!!!

SHEESH!
Click to expand...

Price a set of TTi's lately?

I think if you honed the manifolds you'd come out ahead, especially in the installation headache department!
 
AndyF on moparts had several magazine articles on his B/RB engines... I know he cleared the 500hp mark with at least one of the stroker combos. You should cam it for the loss of scavenging and to eliminate some overlap. The FAST guys use that along with the extrude and hand porting to get the power numbers. Nothing about those cars is as it seems. The LA hp manifolds are pretty good. The HP big block ones are not too shabby. The rest can be tossed to the scrap guy.
 
rmchrgr said:
Price a set of TTi's lately?

I think if you honed the manifolds you'd come out ahead, especially in the installation headache department!
Click to expand...

I'm positive that you're right about the headache portion. Just looking at my engine compartment is enough to make me think about spending money on cast iron.

I got a set of the polished, coated TTI step tubes at Monster Mopar weekend for $625.00 (plus $75.00 drop-shipping).

Seems like the minimum you're going to pay for decent manifolds is $250, and that's not for the HPs.

Still, I'm considering it.
 
Back in 1973 at the winter nal't went 12.53 @109 with stock exh manifolds with the head pipes cut off we painted the head pipes an cut them where the paint stopped changing color this was a pure stocker with dot tires and 4:10 we won class by the way i still have the car 71 demon 340 4 speed
 
I would love to see a picture of that car. Especially if you have one from "back in the day".

Steve
 
Not all the FAST guys are running ExtrudeHoned manifolds so I wouldn't feel that it is a must. Does it help? I am sure it does, but realize they are looking to squeeze every possible thousandth of a second out of their cars and are restricted to using the factory parts without the option of running headers. IMO the extrudehone process on anything less than a very serious effort class specific car such as the FAST cars or the guys running in SuperCarRaces (http://www.supercarraces.com) will be costly and provide marginal if even measurable results. There are a few small block cars in the 12.0 high 11 range that are running stock exhaust manifolds that have only been cleaned up with a die grinder.
 
is expensive but if limited to manifolds, it can be worth it. The problem is that Chevy built a lot of manifolds with increased id and once they have been enlarged by te exrude process it's hard to overcome. I had a 56 Chevy and was lucky enough to come across a set of the maniflolds and in the late 60's I was offered a new set of headers for them. That alone tells you how good they were and what the Chebby croud is willing to do get their hands on them.
 
Here is a website about taking several different sets of exhaust manifolds and headers and comparing them on a mule engine on a dyno. I think the engine was a 360 crate; not sure which one, but the article says, I believe. I just don't have time to look it up right now.


This article is pretty eye-opening, I think.

Click on the little tan-colored menus with the horsepower and torque numbers and they will expand to much larger menus that are a lot easier to read.

Just go to:http://tinyurl.com/6dwlmv


Pretty educational I thought...

Bill
 
Somewhere out there on the internet there's an even better website on which the test involves a more thorough exercise in finding out just which manifolds work and which ones don't.

The testers took two early 340 (swept-back) passenger-side manifolds and tested them on a dyno engine, and the results were amazing. Seems as how that driver's side 340 manifold was KILLING exhaust flow, and when they replaced it with another passenger side manifold (which, of course, you can't do in the car) they picked up a bunch of horsepower. I don't remember how much, but it was on the order of ten or twelve, if I remember correctly. Maybe more...

Something to consider: With that kind of unequal exhaust flow between the two original manifolds, there would be vigorous and constant flow through the under-carb crossover, heating that area of the intake manifold up considerably. Not good...

Perhaps somebody reading this may know where that site is located; I lost the URL, like the dummy I am...

Sorry...
 
I just wish I hadnn't lost the URL for that other exhaust manifold website. It had even more in-depth testing of different combinations, including Dakota manifolds, I believe.

I'll keep digging... :)

Bill
 
rmchrgr said:
I think some of the FAST guys use the extrude honing process to kind of hog out and polish the manifolds. It's expensive, but supposedly it works pretty well. Might be worth a look if you really want to use your manifolds.
Click to expand...

All of the F.A.S.T. guys are stokers with mega roller cams. The Hemis have two of the cylinders switched in firing order to smooth out the idle (the car must have a "stock" sounding idle). Their tricks are not limited to anything internally in the engine. The manifolds are not the key to their speeds, but just a component. Their suspensions are tricked out, the fuel systems are tweaked, they run the lightest combinations possible. It goes on and on. Plus they run on bias ply tires. The fastest right now is a 10.30 from a L-88 Corvette with Dudek's Hemi RR running in the 10.40's at 135mph+. They have tried Extrude Hone, but had better results just from porting the manifolds on the Mopars.

As for my Pure Stock GTS, the best time is a 13.26 @ 103.46 on 205R70-14's on 14x5.5" rims. 3.91 gear, 727 trans. 3600lbs with me in it. No head work, no manifold porting. Factory intake and AVS carb, and factory exhaust manifolds. :)
 
For what it cost to have a set of exhaust manifolds power extruded you can buy a set of tti's..given the choice headers for me everytime...
 
LXguy said:
Hey All

Doing the header procrastination thing, so inevitably, the alternative of just running some hp manifolds has come up.

Has anybody actually run them at the track? How fast did you go?

Thanks!

Steve
Click to expand...

Don't know how fast I went. The speedometer only went to 160 and the cops couldn't catch me to let me know.
 
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