one for the induction gurus,bbc rect int on ovl port heads

[moeraces]

Ok Induction guys i would like for someone to settle this arguement for me once and for all,, I have heard this for years...
I may be wrong ,,,but i had a machinist tell me in a machine shop,,las t weeka,,,,,,supposed reputable , one,,,,mind u ,never had any work done there ,,,but guy is supposed to be top notch....
we were discussing intake ,head combinations,,,
he said that it was possible to gain horsepower and torque on a bbc engine by installing a rect port intake on a oval port ,,cyl head ,,i may be completly wrong and sound like i,m from another planet,,i do not believe it ,, i do not see how that is possible given the port difference and mismatch involved.especially on a normally aspirated engine ,,,may not be true on a forced induction bulet ,,,but it still sounds illogical...to me.
I would however consider a possibility if the mating were opposite ,reversed,,, an oval port intake on a rect port head...that it should work fine ....
I debated this point with him ,and he was steadfast on his statement ,,,can this be true ???,,,he actually quoted horsepower torque figure to be increased .......?????
my owy experiece with this is limited ,,,to knowing a fellowwho purchased a car years ago witha 427 bbc ,it was sick for a fresh new engine,,,,ran awful,,,,after further investigation,,, it was found to have an edelbrock c -427-x rect port intake on a oval port head. he then changed it out and ran like a different car,,,,,

[johnh]

Inquiring minds want to know. Good question.

[sunsation540]

the larger rec port intake to a smaller oval would be a miss match to say the least.. given the area of the rec port that is 1/2 inch shorter in over all hight a real choking point,, however you may have this backwards.. we put oval port intakes on bigger rec port heads to increase the torque and low speed response.. that trick is worth 35-40 lbs of torque and hp loss of 12.. but the torque in the lower ranges especialy in a heavy car always picked up ET.. like alcohol they will not make big hp swings but the torque increase we make most anything et harder,,

[Mike Peters]

the larger rec port intake to a smaller oval would be a miss match to say the least.. given the area of the rec port that is 1/2 inch shorter in over all hight a real choking point,, however you may have this backwards.. we put oval port intakes on bigger rec port heads to increase the torque and low speed response.. that trick is worth 35-40 lbs of torque and hp loss of 12.. but the torque in the lower ranges especialy in a heavy car always picked up ET.. like alcohol they will not make big hp swings but the torque increase we make most anything et harder,,

Yeah, what John said....... I think that info you were given is backwards.

[moeraces]

thats abt the figure he qouted ,but he said it was rect on oval,,i thought then and ,i agree with you guys ,,,that he's got it backwards.

[supernova]

That was a trick the super stock dragracers did back in the old days to make more tq.
Rectangle heads and oval intake. Very old school and worked great on bad ass street cars back in the day.

[go to guy]

Ok Induction guys i would like for someone to settle this arguement for me once and for all,, I have heard this for years...
I may be wrong ,,,but i had a machinist tell me in a machine shop,,las t weeka,,,,,,supposed reputable , one,,,,mind u ,never had any work done there ,,,but guy is supposed to be top notch....
we were discussing intake ,head combinations,,,
he said that it was possible to gain horsepower and torque on a bbc engine by installing a rect port intake on a oval port ,,cyl head ,,i may be completly wrong and sound like i,m from another planet,,i do not believe it

Believe it!


This 11:1 468 with GM cast iron oval port heads makes at least 725HP@ 6300 and 600+ ft./lbs. torque @ 5100 RPM! Some say at least 750HP!!



Ran a best of 10.07 @ 131 and 1.28 60 foot in my nearly 3900 lb. Chevelle leaving off the footbrake...

http://s381.photobucket.com/albums/oo26 ... ent=10.flv

as well it ran quicker and faster than EVERY 454, 496, 502, GM's 720HP 572 and most 540's in a similar Chevelle here in Division 1 brackets with a Holley Strip Dominator RECTANGULAR port intake manifold!

Before the Strip Dominator, it was run for many years with a Performer RPM Rectangular port intake manifold!

i agree with you guys ,,,that he's got it backwards.

Still think he got it backwards?

[shadetree]

http://www.speedtalk.com/forum/viewtopi ... =oval+port

[supernova]

Ok Induction guys i would like for someone to settle this arguement for me once and for all,, I have heard this for years...
I may be wrong ,,,but i had a machinist tell me in a machine shop,,las t weeka,,,,,,supposed reputable , one,,,,mind u ,never had any work done there ,,,but guy is supposed to be top notch....
we were discussing intake ,head combinations,,,
he said that it was possible to gain horsepower and torque on a bbc engine by installing a rect port intake on a oval port ,,cyl head ,,i may be completly wrong and sound like i,m from another planet,,i do not believe it

Believe it!


This 11:1 468 with GM cast iron oval port heads makes at least 725HP@ 6300 and 600+ ft./lbs. torque @ 5100 RPM! Some say at least 750HP!!




Ran a best of 10.07 @ 131 and 1.28 60 foot in my nearly 3900 lb. Chevelle leaving off the footbrake...

http://s381.photobucket.com/albums/oo26 ... ent=10.flv

as well it ran quicker and faster than EVERY 454, 496, 502, GM's 720HP 572 and most 540's in a similar Chevelle here in Division 1 brackets with a Holley Strip Dominator RECTANGULAR port intake manifold!

Before the Strip Dominator, it was run for many years with a Performer RPM Rectangular port intake manifold!

i agree with you guys ,,,that he's got it backwards.

Still think he got it backwards?

Is this your car? I now this car it belongs to or did belong to the one and only, none other, the one we all love on this web site and many others with to many call names to list. I'll try, foot breaker, bracket race, the one and only racer in the world that knows everything guru, the one that doesn't play well with others, the legend in his own mind and so on and so on.
Ed is this you??????
Hi Ed!!!!


Sorry dude but a 10.07 is good for may be 700 hp not 750 + and if thats the best time it's been may be it would make more power with right intake on it!!!!!

[go to guy]

More CLUELESS comments again from one that thinks he knows who ain't done shit nor has shit worth talking about!

[Hitchcock]

More CLUELESS comments again from one that thinks he knows who ain't done shit nor has shit worth talking about!

Isn't this the kind of crap that got you booted. Supernova called you out because of your constant attitude displayed above. Both provoked, or unprovoked. If your gonna try and rejoin our community, please keep that stuff at bay. Otherwise your just wasting a bunch of peoples time.



As far as the question above, I think people are suprised by how much power can be made with a rect. port to oval port mismatch. 30 years ago it was the hot ticket. But with modern cylinder head and intake technology your better off with a tuned and matched set up.

[go to guy]

As far as the question above, I think people are suprised by how much power can be made with a rect. port to oval port mismatch. 30 years ago it was the hot ticket. But with modern cylinder head and intake technology your better off with a tuned and matched set up.

What message board and/or magazine did you read that on/in?

Meanwhile...



920HP, oval port heads topped with a Vic Jr. rectangular port manifold!

[Hitchcock]

If it was the way to get things done, why do the fastest N/A drag racing cars use that theory? If it works for you great. But that dosent mean that everyone else is wrong. Show me one Pro Stocker doing it. Sure there are a few guys doing it, that does not mean every car doing it has more power than its matched induction counterpart.

[go to guy]

You've got an aweful lot to learn yet you're offering advice!

Too fucking funny!

[supernova]

I will travel any where you want to meet with my STREET CAR for a Challange best 2 out of 3 title for title!!!!!!!!!!!!!!! Yes it is a CHALLANGE Your car and my car. I even bracket race your dumb ass!!!!!!!!!!