reverse flow?

B

bet on black

Member
has anybody ever tried or seen somebody try to reverse flow the cylinder head? what i mean by that is switch intake and exhaust ports. you really just need to install the distributor 180 out for it to run that way, right?

since there are 8 exhaust ports, one for each cylinder, you can get around fuel distribution issues with port fuel injection. siamesed exhaust runners wouldn't hurt too much i don't think. 4 ports makes it easy to make a turbo header. ;)
 
Reverse-Flow Head

bet on black said:
has anybody ever tried or seen somebody try to reverse flow the cylinder head? what i mean by that is switch intake and exhaust ports. you really just need to install the distributor 180 out for it to run that way, right?

since there are 8 exhaust ports, one for each cylinder, you can get around fuel distribution issues with port fuel injection. siamesed exhaust runners wouldn't hurt too much i don't think. 4 ports makes it easy to make a turbo header. ;)
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What would be the advantage of this? Build a new header out of tubing; forget swapping the ports around.
For one thing, the cam and valve timing would all be off. The firing order and ignition timing would be the same; you would just be swapping the function of the intake and exhaust valves, so you would need a different camshaft (each pair of lobes would swap positions).
 
the Buick straight 8 shares intake ports in pairs. it's one of the great performance bottlenecks on the engine.

if you reverse flow the engine and feed the turbo off of what are now exh ports, i presume that the restricted port cross section wouldn't matter near as much.

this actually was done on a Buick, but on a Nailhead v8 dragster. it's really weird to see a exhaust stacks sticking out of the 'intake' valley. the intake ports are also a major restriction on the Nail.

http://forums.pelicanparts.com/uploads21/Nailhead_Powered_Dragster1358424165.jpg

Nailhead_Powered_Dragster1358424165.jpg
 
Well I, kind of like that, its been done before but havnt seen anything about results, Buick straight 8,s have fairly good flowing exh ports and flow IS important!
 
I have seen that done on Fords, but I thought it was to get cooler running, because the stock setup runs the exhaust through the water jacket. Fords have only 3 exhaust ports, so how would it help to use them for intake?

Ray
 
bob k. mando said:
the Buick straight 8 shares intake ports in pairs. it's one of the great performance bottlenecks on the engine.

if you reverse flow the engine and feed the turbo off of what are now exh ports, i presume that the restricted port cross section wouldn't matter near as much.

this actually was done on a Buick, but on a Nailhead v8 dragster. it's really weird to see a exhaust stacks sticking out of the 'intake' valley. the intake ports are also a major restriction on the Nail.

http://forums.pelicanparts.com/uploads21/Nailhead_Powered_Dragster1358424165.jpg

View attachment 4032
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that's exactly what i was thinking. once the turbo spools up, the exhaust ports don't matter as much, and the siamesed ports shouldn't hurt exhaust flow as much as the fuel distribution problemcould be a major tuning issue. plus its different.
 
raycow said:
I have seen that done on Fords, but I thought it was to get cooler running, because the stock setup runs the exhaust through the water jacket. Fords have only 3 exhaust ports, so how would it help to use them for intake?

Ray
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Im not sure what their thought process was that made them think they needed to do it, but many did. The current Flathead Ford powered record holder Bonneville streamliner of Ron Main is done that way. It has the record at a little over 300 MPH, so it must help when trying to build an engine to that degree of power.
 
bet on black said:
better fuel distribution on a forced induction application (turbo) :thumbsup:
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and by better, i mean that in reference to converting to multi-port efi to maintain precise fuel control over each cylinder, by having one intake port for each cylinder with it's fuel injector in that intake manifold runner.
 
well buick straight 8,s have big problem on intake side, they have been tweeked and modified to obtain pretty amazing performance in spite of not having the best breathing. The intake looks like its made for a tractor, and then is saddled with siamese ports, then they made it worse with the forties intake manifolds even the 4 barrel manifold has 90 degree bends. A lot can be said for using the exhaust ports with individual smooth flowing ports. Good flow many times trump bad intake porting. Also a blower or turbo would really work, just my thoughts on the matter.
 
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hidden carrb

By the way while talking unusual porting, has anybody seen the Ford flatty with a 'hidden carb under the intake manifold'??? Dont recall

what kinda carb it was but it took in air from the oil filler hole and blowby tubes. nobody figured out why he was so fast !!!

I think it was a midwest roundy round car or something like that, it blew me away when I saw it. I'll try and find it. I thought I had seen it on the web someone had done that to an ford flathead!-----anyway guy fooled everyone, it ran away from the competition, I think it was a small one barrel carb ! I,m still searching, he donated it to a museum, Hey! I couldnt have dreamt this up!
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i'd like to do it, but i'm sure the camshaft machining is where the project just gets too expensive to do it. i already have the turbo header and intake planned out. who knows, I've done dumber things with money.
 
has anybody seen the Ford flatty with a hidden carb under the intake manifold???


never heard of it. was it used in early NASCAR or something?
 
reverse flow head

I think it was a midwest roundy round car or something like that, it blew me away when I saw it. I'll try and find it. I thought I had seen it on the web someone had done that to an ford flathead!-----anyway guy fooled everyone, it ran away from the competition, I think it was a small one barrel carb ! I,m still searching, he donated it to a museum or somthing, I couldnt have dreamt this up!
 
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Backwards Buick Nailhead

bet on black said:
has anybody ever tried or seen somebody try to reverse flow the cylinder head? what i mean by that is switch intake and exhaust ports. you really just need to install the distributor 180 out for it to run that way, right?

since there are 8 exhaust ports, one for each cylinder, you can get around fuel distribution issues with port fuel injection. siamesed exhaust runners wouldn't hurt too much i don't think. 4 ports makes it easy to make a turbo header. ;)
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Yes, my husband did this in the late 90s. Runs great!
 
Yes

He had it custom made by Howard Cam back then. It has been over 20 yrs. Anyone can do it, today they would likely use a computer and have the cam locations changed. He would need to be a Bilett Cam. One with a roller shaft.
Not sure how it would work on a street application due to the heat. It requires a higher cooling capacity. We have our in a boat. Feel free to email him at mjpelphrey@yahoo.com if you like to discuss further. He doesn’t mind y’all to others about it.
 
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