Rectangle port intake on oval port heads. - Chevelle Tech
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post #1 of 13 (permalink) Old Dec 2nd, 19, 3:20 AM Thread Starter
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Durand
 
Join Date: Dec 2015
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Rectangle port intake on oval port heads.

There have been numerous posts of people using the factory dual plane aluminum rectangular intakes on oval port heads with good success.
With that in mind, would the same be true with a single plane intake?


Ran across an old rectangular port Team-G intake digging around in the garage that got me pondering.


I have a dyno mule engine of sorts in my car right now for the time being.
461cid, 781's, 230/236 @.050- .552/.555, Performer 2-o, 800 cfm Q-jet.
The performance is acceptable, but seems restricted and plateau's of sorts in the upper RPM's I believe is intake related.
I will be doing some track testing, between the 2-0 and a molested factory cast iron high rise oval intake.
So figured why not try the Team-G also.


To try and keep the experiment as apples to apples as possible I'd like to use the same Q-jet on all the intakes.


So the main question/questions is/are;
Running the Q-jet on the Team-G's dominator flange.
(Adapting a spread bore onto a standard square bore intake, leaves something to be desired in the flow path department in my opinion with the spread bore's large secondary butterfly size and would skew testing where the dominator flange would not.)
Would it be worth making an adaptor for the Team-G and adding it to the testing, or would it be overkill and a waste of time being a high RPM intake? (I can mill out an adaptor for 5 bucks worth of bolts and material laying around the garage.)


I know, put a Performer RPM on it, but that costs money.
I'd rather buy the crank trigger for the new engine, than another intake for this one.
It's a temporary engine and just thought about doing some inexpensive intake testing this spring before removing it.

65 Pontiac Lemans 468 BBC, t400, 4.10 12bolt

Best 1/4 mile. 11.43 @ 118 mph
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post #2 of 13 (permalink) Old Dec 2nd, 19, 4:04 AM
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Jani Heino
 
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Carb gasket surface in team g intake is very wide compared to edelbrock intakes so it may have enough materia to match it for q-jet. Not sure is it possible but it is close.
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post #3 of 13 (permalink) Old Dec 2nd, 19, 2:54 PM
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Tom
 
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Re: Rectangle port intake on oval port heads.

In past years, several of the BB engine "experts" have flatly stated that installing a rectangle port intake on oval port heads would cause a flow reversion at the mating ports and it just would not work well.
Several members here on TC have used rect port intakes on oval port heads with excellent success.
So that has pretty well dispelled that "old wives tell"!
Now, with that said, you CANNOT go the other way. An oval port intake WILL NOT WORK on rect port heads because the upper part of the port in the head will be exposed.

Tom Parsons
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post #4 of 13 (permalink) Old Dec 2nd, 19, 4:30 PM
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Re: Rectangle port intake on oval port heads.

The Q-jet will not work very well on that intake as you have super big secondaries and tiny primaries that will cause mixture distribution troubles. As for the Performer 2-0 back in the late 80's prior to the Performer RPM coming out I ported the openings out the oval ports on my 781's and that made a huge difference.
When I got my RPM intake it was 1 tenth and 1 mph better over the port matched Performer 2-0. Can't hurt to try the Team G, It would be better if it were an oval port.
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post #5 of 13 (permalink) Old Dec 2nd, 19, 7:02 PM
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jeff
 
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Re: Rectangle port intake on oval port heads.

I say you have them so go for it .. only takes time and a few gaskets.
Money well spent and you will know if it works on your combo.

I stuck my SBC in a wheel dyno and tested the Edelbrock RPM intake against a stock iron marine Q jet intake and then stuck on a plenum Ported Q jet iron automotive intake.
I tested with 2 carbs A well tuned Q jet and a Holley 750 double pumper which was much modified.

On the RPM intake the Holley square bore made 10 HP more than the Q jet. But the Q jet made 10 HP more on the Q jet ported intake.

Later i stuck on a tunnel-ram and made 53 more HP everywhere than the RPM which won the above test against the other intakes by 10HP.

I like swapping intakes too see what happens.
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post #6 of 13 (permalink) Old Dec 2nd, 19, 8:57 PM
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Re: Rectangle port intake on oval port heads.

I picked up a edlebrock air gap rpm endura shine intake for cheap. even though it's a rec port intake I plan on using it because it's what I have. still havent decided on the heads. 063 ovals or rpm rovals on a reringed flat top 454.
I say if you have it, use it. jim
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Jim

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post #7 of 13 (permalink) Old Dec 3rd, 19, 6:13 AM Thread Starter
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Durand
 
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Re: Rectangle port intake on oval port heads.

Quote:
Originally Posted by Janih View Post
Carb gasket surface in team g intake is very wide compared to edelbrock intakes so it may have enough materia to match it for q-jet. Not sure is it possible but it is close.
Yes it does.
The outside width of the secondary's is slightly smaller than the dominator's square flange width.

65 Pontiac Lemans 468 BBC, t400, 4.10 12bolt

Best 1/4 mile. 11.43 @ 118 mph
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post #8 of 13 (permalink) Old Dec 3rd, 19, 7:08 AM Thread Starter
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Durand
 
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Re: Rectangle port intake on oval port heads.

Quote:
Originally Posted by 68Chevele View Post
The Q-jet will not work very well on that intake as you have super big secondaries and tiny primaries that will cause mixture distribution troubles. As for the Performer 2-0 back in the late 80's prior to the Performer RPM coming out I ported the openings out the oval ports on my 781's and that made a huge difference.
When I got my RPM intake it was 1 tenth and 1 mph better over the port matched Performer 2-0. Can't hurt to try the Team G, It would be better if it were an oval port.
Not to argue, but I beg to differ. It really wouldn't much different than an open spacer on top a dual plane intake. Along with Holley doesn't seem to have an issue with using it on a big Mopar. https://www.summitracing.com/parts/hly-300-14/overview/
With the Team-G's small runner size ( for a single plane ) I think it might work well
I've even pondered trying a pair of Q-jet's on a tunnel ram for street duty.


On the 2-o I matched the ports to the heads, ( They come from Eddy set for peanut ports) so that isn't the issue.
To me the runner design on the 2-o sucks. ( Squared runner corners and such. )
Runner shape and velocity is more important than size a lot of times.
Which is why I'll be testing the molested iron high rise against it. (My money is on the iron intake.)
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65 Pontiac Lemans 468 BBC, t400, 4.10 12bolt

Best 1/4 mile. 11.43 @ 118 mph
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post #9 of 13 (permalink) Old Dec 3rd, 19, 7:29 AM Thread Starter
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Durand
 
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Re: Rectangle port intake on oval port heads.

Quote:
Originally Posted by jeff swisher View Post
I say you have them so go for it .. only takes time and a few gaskets.
Money well spent and you will know if it works on your combo.

I stuck my SBC in a wheel dyno and tested the Edelbrock RPM intake against a stock iron marine Q jet intake and then stuck on a plenum Ported Q jet iron automotive intake.
I tested with 2 carbs A well tuned Q jet and a Holley 750 double pumper which was much modified.

On the RPM intake the Holley square bore made 10 HP more than the Q jet. But the Q jet made 10 HP more on the Q jet ported intake.

Later i stuck on a tunnel-ram and made 53 more HP everywhere than the RPM which won the above test against the other intakes by 10HP.

I like swapping intakes too see what happens.

Going too.
I'm into trying weird unconventional thinking and things sometimes.( making more from less theory )
Which got me to playing with Q-jets and the iron intakes. (got ahold of a couple 800 cfm units and Ruggles book )


Sometimes it's fun to be stealthy and different, it gets the knuckle draggers to scratching their heads instead of their balls wondering why it runs theway it does.
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65 Pontiac Lemans 468 BBC, t400, 4.10 12bolt

Best 1/4 mile. 11.43 @ 118 mph
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post #10 of 13 (permalink) Old Dec 3rd, 19, 7:55 AM
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Gene
 
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Re: Rectangle port intake on oval port heads.

small rect gasket, like a MG 5228 seals it.

Gene
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post #11 of 13 (permalink) Old Dec 3rd, 19, 9:55 AM
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jeff
 
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Re: Rectangle port intake on oval port heads.

It is fun to take "trash" and make it work better than the expensive stuff.

I told my friends when i was in my early 20's that I would make my 350" in my '78 nova run 13's with q jet and an iron intake and the iron exhaust manifolds.. They all said it can't be done you need an aluminum head and a Holley carb and headers to go that quick.

Ran 13.028 at 105 MPH with a Q jet and the iron stuff.
My Uncle was even impressed.
Uniroyal tiger paw tires 3.70 gear TH 350 and a 2000 stall converter.

I did later add headers and the performer RPM intake which had been out about 2 years and a carter AFB 750.
It went 12.55 with that stuff and the same tires.. Getting it to hook up in first gear was not happening.

Lots of porting and milling. Little 270H comp cam was used.
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post #12 of 13 (permalink) Old Yesterday, 5:51 AM Thread Starter
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Durand
 
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Posts: 444
Re: Rectangle port intake on oval port heads.

Funny, I still have my little daily driver 327 from my 20's on an engine stand carb to pan and ready to run.
It will run 13.50's in the Lemans.
Little smaller cam than your 350's w/flat tops, and a well done top end ( Joe Mondello ported) set of camel humps, Eddy TM1 intake, and 600 Holley.

65 Pontiac Lemans 468 BBC, t400, 4.10 12bolt

Best 1/4 mile. 11.43 @ 118 mph
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post #13 of 13 (permalink) Old Yesterday, 11:04 AM
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Re: Rectangle port intake on oval port heads.

Quote:
Originally Posted by LaVelle View Post
Not to argue, but I beg to differ. It really wouldn't much different than an open spacer on top a dual plane intake. Along with Holley doesn't seem to have an issue with using it on a big Mopar. https://www.summitracing.com/parts/hly-300-14/overview/
With the Team-G's small runner size ( for a single plane ) I think it might work well
I've even pondered trying a pair of Q-jet's on a tunnel ram for street duty.


On the 2-o I matched the ports to the heads, ( They come from Eddy set for peanut ports) so that isn't the issue.
To me the runner design on the 2-o sucks. ( Squared runner corners and such. )
Runner shape and velocity is more important than size a lot of times.
Which is why I'll be testing the molested iron high rise against it. (My money is on the iron intake.)
You are right, that intake would work very well. Te problem is that it is HEAVY and if one is trying to get their car to pitch and roll off the starting line the weight does not help that's why the aluminum intake is so much more helpful. I have run as quick as 11.78 with a 396 back in 1994 after running the sq. port deal on oval heads. The 163 intake ran the best of 12.03 so even though you can bolt it on and the sq. port intake will work, sometimes it's not the best deal at the track. Nice work on that plenum.
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