can you use a rect port man on oval heads ?

[74_schiada_flat]

can you use a rect port man on oval heads?
someone said no problemo if you use oval gaskets.

[Fiat48]

Not the best but it does work.

[74_schiada_flat]

Not the best but it does work.
hard to get a good seal?
or just for flow?

[GofastRacer]

I did it and it worked great BUT you need to blend the ports and you have to be careful, it's real easy to break thru the casting it's thin on the top, just blend the minimum and you'll be ok!..

[GofastRacer]

hard to get a good seal?
or just for flow?
No problem sealing, just remember it's not square port heads!.

[74_schiada_flat]

No problem sealing, just remember it's not square port heads!.
thats not even the worst part about the problem. i am going to be using a square port tunnel ram with square port spacers on a talldeck with oval heads.
this should be interesting.

[76BARRON]

and switching heads is not an option?

[74_schiada_flat]

and switching heads is not an option?
looking for some but cant find any i can afford right now.
i figure ill just run it like that for this season.

[76BARRON]

Long Beach swap meet! Next one is May 8
Last time(4/10) I saw a few set's ,some of them fully prep'd or assembled
in the 500.00 range from dealers/regulars at swapmeet.Not sombody you will never see again. Just an F.Y.I.

[74_schiada_flat]

Long Beach swap meet! Next one is May 8
Last time(4/10) I saw a few set's ,some of them fully prep'd or assembled
in the 500.00 range from dealers/regulars at swapmeet.Not sombody you will never see again. Just an F.Y.I.
thank you! i was thinking about going to pamona sunday.

[victorfb]

wouldnt it be easier and less expensive to buy an oval port tunnel ram? buying new heads and then having them checked, straightened, new gaskets, ect. will be costly. i know alot of people think if you want to go fast you need the rect. port heads but im still not a believer in that. your large oval ports were designed very well and will perform extremely well with the right set up. especially with the tunnel ram were you need the velocity. just a thought.
oh and useing the oval heads with rect. intake will work but you will have a large restriction at the top of the port. there is not much material there on the head to blend enough that is safe and that will make it work, unless you have the GM aluminum heads that use the same castings as the rect. port heads. the extra material can be removed from those, and actually works well. but thats not an option in your case. i would find an oval port tunnel ram since you want to use the 2 carbs, and use the cam to control your intake. thats actually the key. cam timing and duration will make those large ovals work extremely well.

[Speedin' Ian]

I have a set of 990's I may be selling cheap with nice valves, ported and polished and new roller springs. However they would need a valve job and they are about 126cc

[lost boy]

get the oval port tunnel ram and you will be a happy camper! and alot less hassle.

[jmm]

Back a few years ago Hot Rod did a story on this very same subject. They did some Dyno testing. They ran ovals with a square port intake. It made more power with the sqaure to oval then oval to oval. They said it was due to a better mix of the fuel and air from the turbulence of the edge of the port.
I also know a guy running a Hydro with this set-up who runs over 100 m.p.h. with no problems..... :rollside:

[GofastRacer]

Back in the 80's a big name engine builder was doing that with success, damn can't remember who it was though!. :hammerhea :confused:

[Speedin' Ian]

Not sure if I should say who was doing this but the guy who does my heads also does the heads for a very famous motor builder. Back in the day when they were running circle boats (jets I believe) they were dominating with that very set-up, square port intake on oval port heads that they converted to square port heads. Supposedly they even broke the kilo record at that time, so when I was deciding what heads to run he dug these heads out, but we decided to go with some CNC ported VIctors instead.

[CircleJerk]

It works better than anyone would expect!!! Desperate deeds and mismatched inexpensive combinations, sometimes produce respectable performance and this is one example.