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I apologize, I should have said these are for a 4V head. But they can be used on 2V application as well. Ive seen all the posts on this subject and while I have no personal experience it seems there are no documented drawbacks to using 4V headers on 2V heads. However there are some who theorize that the 1 3/4 primary, 2 3/4 " collector that PPC sells is a better match for 2V heads. My opinion, $150 is a good deal either way. The tubes are 1 7/8" primaries with 2" collector. They will bolt up to stock non GTS exhaust. I had these on my car with CHI alum heads which have much smaller ex ports than my old 4V heads. They worked good. But I thought that I might gain some HP so I changed to PI "Big Throat" headers. I really can't tell a seat of the pants difference but my wallet is lighter which may account for a lower ET at the strip. $750 and some skin off my knuckles for that experiment when all was finished.
I didn't use PPC headers. I now have PI "Big Throat" headers. They're good headers, fit well, look good coated, no hassel installation even with my slightly raised exhaust ports.
According to the folks at PPC, their headers come with collector adaptors to weld to your pipes.
David,
How do you like the CHI heads? What did you use for an intake manifold?
Alan

quote:
Originally posted by David:
I apologize, I should have said these are for a 4V head. But they can be used on 2V application as well. Ive seen all the posts on this subject and while I have no personal experience it seems there are no documented drawbacks to using 4V headers on 2V heads. However there are some who theorize that the 1 3/4 primary, 2 3/4 " collector that PPC sells is a better match for 2V heads. My opinion, $150 is a good deal either way. The tubes are 1 7/8" primaries with 2" collector. They will bolt up to stock non GTS exhaust. I had these on my car with CHI alum heads which have much smaller ex ports than my old 4V heads. They worked good. But I thought that I might gain some HP so I changed to PI "Big Throat" headers. I really can't tell a seat of the pants difference but my wallet is lighter which may account for a lower ET at the strip. $750 and some skin off my knuckles for that experiment when all was finished.




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CHI heads were worth the price paid. I have improvement through all RPM ranges but especially noticeable in the low and midrange. Throttle response improved and more vacuum with bigger cam. The intake is a TFC single plane that was port matched and a "Mighty Demon" 750 carb. I have pics but I cant figure out how to paste it to this post.
Dave,
Thanks for the info. The CHI web page now has matching intakes listed for both their 185CC and 218CC aluminum heads. Which heads do you have? I talked to them and they suggested the smaller ports for the street.

I just picked up a set of "bundle of snake" 180 Deg. type headers. Do you think they would work with the CHI heads?


quote:
Originally posted by David:
CHI heads were worth the price paid. I have improvement through all RPM ranges but especially noticeable in the low and midrange. Throttle response improved and more vacuum with bigger cam. The intake is a TFC single plane that was port matched and a "Mighty Demon" 750 carb. I have pics but I cant figure out how to paste it to this post.




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Oh by the way. There are some things that are not mentioned in the sales brochures. 1.They recommend head studs. Its easier to do this when engine out of the car.
2. you have to elongate the intake bolt holes to line up with the heads (unless they fixed that)and use a big gob of silicone at the end rails.
3. If you have open chamber heads now with a domed piston you will need new pistons.
4. I used REV valves, 2.15 intake with 1.65 exhaust. The exhaust valves had to be cut by REV from a standard 1.71 clevland valve.
The rest is all Crane valve train.
I think those headers will work. The exhaust port is raised a bit which may make it difficult. I'm sure I've seen others out there with raised port heads and 180 headers.
I may think of other things later.
quote:
Originally posted by Alan B:
I just picked up a set of "bundle of snake" 180 Deg. type headers. Do you think they would work with the CHI heads?







I just bolted a set of Hall's 180 deg. headers on a set of CHI heads for a friend.
They had been cut in the middle to fit a set of "high ported" 4V heads(the 4 pipes that cross in the middle were cut,expanded and spaced) so the raised exhaust port wasn't a concern.It also makes installing them ALOT easier.

Ron



[This message has been edited by r mccall (edited 03-24-2004).]
I was wondering if they would need to be cut. I figured the distance from port to port across the engine would grow as the ports moved up the head. Were the new pieces welded in while the headers were bolted in place? How does your friend like the heads?

Alan

quote:
Originally posted by r mccall:
I just bolted a set of Hall's 180 deg. headers on a set of CHI heads for a friend.
They had been cut in the middle to fit a set of "high ported" 4V heads(the 4 pipes that cross in the middle were cut,expanded and spaced) so the raised exhaust port wasn't a concern.It also makes installing them ALOT easier.

Ron

[This message has been edited by r mccall (edited 03-24-2004).]





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I think they would have to be cut.I had them on my car with the "high port" iron heads (exhaust raised just over 1") and they had about 1 1/2" to 2" of space where they had been cut.On the CHI heads there is about 3/4" to 1" between the cuts.I didn't weld them I just used the stainless steel band clamps to seal them.They didn't leak at all.
We are firing the engine for the 1st time tomorrow.I'll let you know how it runs.
Ron

[This message has been edited by r mccall (edited 03-26-2004).]
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