1968 HP exhaust manifold

GOLDMYN

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I was able to purchase the drivers-side hp exhaust manifold and no passenger-side. For now, I'm going to install what I have, just want opinions in-case there's a reason I should not install what I have. 1968 Chrysler 440 engine
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DSC05125.JPG
 
Assuming you still have the LoPo left side why not wait until you get a right side to make a HP pair before making the change?
 
You will have uneven exhaust flow running two different sets of manifolds. This can make the engine very difficult to tune and has the potential to cause burnt valves do to problems with different mixture settings on the right and left. The performance exhaust will need to be tuned richer to get those 4 cylinders to run right. Wait until you have both manifolds to install them.

Dave
 
The right side HP exhaust manifolds are the same as on a B Body and are being reproduced at a reasonable price.
 
I will only confuse the issue but not negate the previous posts in any way by saying the HP manifolds although cool ,do not flow much more from the stock log manifolds by any appreciable margin. I actually hope they do . If I am wrong please give me some data. But I do agree to swap them as pairs and not one at a time cause who the f#ck knows.
 
I'm kind of surprised that it would be that drastic a difference. I could see an issue having a log on one side and running a header on the other, but who would do that ...right? LOL I agree with the guys. I'd wait too. I mean, why not do it all at once. If it's at the shop and on the hoist...

I didn't buy the HP manifolds because everything I could find out about them suggested that I would only gain 5 or 6 horses over the logs, assuming duals. It stands to reason that if the logs were running through a single exhaust, then you installed duals when you installed the HPs, you would see higher gains. I also came away with the impression that the HPs were more prone to cracking than the logs. The other reason I didn't bother was because when I installed duals with turbo mufflers on my 390, which was just running basic manifolds, I was very impressed and satisfied with the gains. So much so, that I decided against the headers I'd been considering.
 
I only paid $50.00 for this manifold, I'll wait till I find a similar bargain for the passenger-side
 
Rather expensive on ebay. Cheapest I found was 400 for a set. At that price headers seem to be a better option. Anyone put headers on their c-body? What type? I looked at TTI but they were really expensive. Stainless steel though. From what I've read b-body versions have clearance issues with the passenger side hitting the upper control arm mount. Headers would be a decent performance upgrade. From other posts you probably need them if you go to a cylinder head upgrade due to the angled plug design too. So they would be a good first step in the aluminum head upgrade path. Always thinking about upgrades for the 440.
 
Is there an easy way to tell the HP manifold from the regular one? I have a 66 fury someone had a 440 in it at some point. The only thing left in the car is the RH manifold attached to the exhaust. It looks exactly like the one linked. I don't plan on using manifolds on this car...
 
The standard version looks like this:
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Passenger side is similar with a valve in the pipe going downward. A thermostatic spring opens/closes it. It closes when the engine is cold and helps with directing heat through the intake manifold passage under the carburetor. Opens when the engine warms up. It is usually stuck on old manifolds due to rust. Hopefully in the open position.
 
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