Hi folks,
I wrote Wilson manifolds and asked the "what intake to use on my 496" question. The response was all Edelbrock stuff.....with their fav being the RPM air gap. Gads, that's all I need is more toeque than I can use below the converter stall speed. I assume Wilson is quite good, but also does work for Edelbrock.
I'm not even going to mention what they said they would tune up the RPM for $$$$ wise. But lets just say I could buy all the manifolds I'm considering and have $$$$ left over.
Maybe I shouldn't have mentioned the words street/strip in my email. It was however quite nice that they responded to my email....many companies have email available....but never respond.
Along those lines, anyone read Hot Rod mags latest rat motor intake comparrison article? All Edelbrock intakes. Gee, and guess what won...duh...the RPM air gap.....which is simply an RPM with the middle portion cut out for airflow to keep it cooler.....like that matters after the hood is closed and you have just driven 20 miles in 90 degree temps to the track. Of course we all carry a bucket of dry ice to "cool things down".
Me thinks the advertizers have a ton of pull in these articles.
Sigh......
Ron

You can get the same results with the performer RPM and a splash shield in the lifter valley,the Air Gap does keep the HOT oil off the bottom of the intake,gotta be worth sumthin graemlins/thumbsup.gif

I think the carb mounting surface is actually higher on the airgap, maybe the little extra runner length gives the airgap a better turn on the ports? The airgap seems to outpower the regular rpm on every test I've ever seen published, smallblock and bigblock. I've got a teamG oval and also an rpm airgap oval I'll be trying if I ever get the car together. But from what I hear up to 6500 the airgap wins.

I personally like a Holley Strip Dominator. Nearley everyone around here runs that intake on strip and street cars. Just my two cents worth.

Originally posted by baddbob71:
[QB] I think the carb mounting surface is actually higher on the airgap, maybe the little extra runner length gives the airgap a better turn on the ports? The airgap seems to outpower the regular rpm on every test I've ever seen published, smallblock and bigblockThe airgap actually loses some volume due to the airgap design...but not much.Both intakes are the same height.As far as the Airgap being better than regualr RPM..I don't buy that,because an airgap also blocks off the exhaust crossover,and a regular RPM doesn't.To make that a truly fair comparison,any dyno testing should have the exhaust crossover blocked off and the valley sheild installed w/the regular RPM vs. the AirGap..now,its apples to apples.The article in "Hot Rod" is some good info though.Makes me want to get an RPM on my car..I'm still running the 'ole Performer on it.The standard RPM was worth 29 HP/20 ft/lb. TQ over the Performer on a mild crate 454

SB intakes...

A stock cast-iron intake up to say, 3500 to about 4000, then a Performer up to about 5000 to 5500 and the RPM and Air Gap above that until they sign off somewhere around 6500 rpm or so depending on motor size!!

BUT personally, I like the Holley 300-36 intake for a SB, b/c it is a true high-rise!! It's advertised at an off idle to 7200 rpm intake and it is right in there with the old GOOD Z-28 intake only a schosh bigger ported if not mistaken?!!

pdq67

Ron, as far as I know, no one has demonstrably proven that the RPM is worth anything but marginal gains over the GM 163, Weiand Stealth, etc. ( I'd choose the rpm if I had to buy one) I also have little doubt that if a racer tried the RPM vs an AG, the difference would be measured in hundreths if any at all.

But, like fishing lures, they always have to come up with 'new and improved'.

To me the choice might be RPM or Dart single plane, or if it was a true street car, the 3X2 that I enjoy so much.

I better stay in this section...I keep gettin in trouble in the bench racing section,political views too strong I guess :D anyway... Hey Gene, its tough enough to keep one carburetor right,let alone keeping 3 of em right...I think multiple carb setups are neat looking,but I wouldnt want to have to tune em :eek:

If you are considering a single plane intake, I recently got off the dyno with my 540bbc. Trying 3 different intakes, comparing oranges to oranges, I made 24 more horsepower using the Edelbrock Super Victor CNC intake with a one inch spacer. If I would have spun the motor past 7000, it would have made more. :eek: Although this intake cost around $575, I'm happy I spent the extra coin! By the way, Wilson has his name on this intake too. Good Luck! :cool:

70454SS,

Out of curiousity, what other intakes were tested? I posted some results on here earlier this year from some track testing I did. Switching from my trusty Edelbrock Performer RPM to a Victor Jr. Resulted in a loss of both ET and MPH. .25 and 3mph as near as I could tell. I was talking to the guy that built my heads earlier today and he wants me to try a custom Dart single plane OVAL port on my rect port heads. It's an interesting idea, but at a turn key price of $700 for the intake and intake porting, I'll need more than an interest to do that test :D

Has anyone run the Dart dual plane? It looks like a good manifold but looks don't mean anything.

Yesterday I was at Chet Herbert's and ran into John Beck, who had assembled my engine. John knows that a lot of the parts on my 496 were used simply because I already had them. I asked him about switching to an Air Gap from my current Vic Jr. He said that he had done the switcheroo on another customer's 509 that was very similar to my 496: average hp and tq went up 5-7, although the peak hp was lower with the Air Gap. I actually already had an Air Gap, but I didn't use it because it hadn't been cut down to fit my heads the way the Vic Jr had been. John seemed pretty confident that if I did the swap, that it would drop .10 or maybe a little more off my e.t.

So I'm thinking I should take the time to match up the Air Gap smile.gif

Thomas

what does peak HP mean to ET? not much.

I've been told if it's a daily driver in a climate where temps can get a little frosty to stay away from the airgap. I am trying an airgap on my 454, because I was pleased with the performance gain I got when I switched from a performer to an airgap on my 350. We will see what it runs. I don't have very may cubes and a tiny ZZ502 cam, so it doesn't really compare to the real engines you guys run.

Several years ago I read that Dart recomended an Oval Port manifold on door cars with Rectangle Port heads.They said it brought better torque withought the HP sacrifice.

Anyone know if that is true?


I remember reading several times that racer1320 uses just the opposite, an Rectangle Port intake on Oval Port heads.

I also remember him saying that he didn't thing there was a gain doing it the way he did.

Anyone care to comment?

The RPM air gap is just a marketing thing, like those spark plugs that come with 4 ground straps instead of 1. I would just go with a Holley Street Dominator, those flow much better then the air gaps.

Originally posted by thrasher:
Several years ago I read that Dart recomended an Oval Port manifold on door cars with Rectangle Port heads.They said it brought better torque withought the HP sacrifice.

Anyone know if that is true?


I remember reading several times that racer1320 uses just the opposite, an Rectangle Port intake on Oval Port heads.

I also remember him saying that he didn't thing there was a gain doing it the way he did.

Anyone care to comment? The guy I sopke with about this, Tommy Champion of Champion Racing Heads, said he has used this set up with super stock cars running deep into the 9's with great success. Now, it's important to remember that there are many differences between a Super Stock car and the street or street/strip type rides that most of us on this site build (i.e., we use less RPM, gear and usually heavier cars). Having said that, he was pretty confident that it would help the low/mid range torque without sacrificing upper range power. To me it seems reasonable. If you can keep the same cross-sectional area and improve velocity torque should increase. I don't mean to over simplify the many factors that are involved in the induction system (runner length and tuning, impulse reversion, runner floor and roof design, etc...) which can make selecting the best induction system difficult to say the least. I may soon be able to report back on whether this works or doesn't. Trying to work out a deal as I type ;)

The following link makes for some interesting reading on different intakes design and the pros/cons of each:

http://victorylibrary.com/mopar/intake-tech-c.htm

We use a Dart "conversion" manifold on our 534" motor.
It`s a single plane oval to rect port set up.
Originaly, I had the standard oval port version sent, I planned on matching the ports on it to the Dart 325`s...NO WAY!!... the ports in the manifold were so small it looked as though a ping-pong ball would have a tough time going through them!.
I would have spent countless hours with my arms numb up to my elbows grinding away and who knows if it would`ve been right; so for $500+ we had the CNC`d version sent instead, money well spent IMO.
So far the car has run decent times for a pump gas 10.25 comp car that weighs 3700 LBS + with driver....10.19 ET @ 130+ mph street driven, never, ever, trailered any where including drives up to Daytona.
Anyway the manifold works ;)

Guys,
Don't make me cry tears.......
I just sold my Dart oval port single plane along with the Edel "roval" port heads cause I had matched the manifold to them........
Perhaps I should have kept it and tried it as is.
I agree with the ping pong ball sized ports as delivered by the way.
So by "conversion" manifold, I assume that you mean one that Dart starts out as the oval port model then CNC port matches to your heads?

Another manifold that looks interesting is the Merlin/World products single plane. I believe Dart and World products were nce associated with each other? Or maybe even the same company? Anyway, it sounds quite like the Dart but with a smaller plenum.

I went to the NHRA Div 6 points race today at Woodburn dragstrip.....so that got the blood for some 1/4 mile blasts flowin again.

Ron

Originally posted by Ron454:
So by "conversion" manifold, I assume that you mean one that Dart starts out as the oval port model then CNC port matches to your heads? Ron YES

kjett,

The other intakes we used were a Dart single plane and a Brodix single plane. One inch spacers were used on all three intakes.

70ss540

BigRed-L72,
Dart's web site has little to no info on their manifolds. Perhaps I should write them.

I have sent a rather detailed email to World/Merlin concerning their new manifolds. Seems that what they have mey be a cross between the Dart oval and rect manifolds. I'll see what they say.

70SS540, those were all dominator manifolds correct? I really don't think my little 498 is going to move enough air for the Super Victor CNC manifold, and a dominator just isn't in the equation at the present time.

Thanks again for all the responses.

Ron

Originally posted by BigRed-L72:
We use a Dart "conversion" manifold on our 534" motor.
It`s a single plane oval to rect port set up.
Originaly, I had the standard oval port version sent, I planned on matching the ports on it to the Dart 325`s...NO WAY!!... the ports in the manifold were so small it looked as though a ping-pong ball would have a tough time going through them!.
I would have spent countless hours with my arms numb up to my elbows grinding away and who knows if it would`ve been right; so for $500+ we had the CNC`d version sent instead, money well spent IMO.
So far the car has run decent times for a pump gas 10.25 comp car that weighs 3700 LBS + with driver....10.19 ET @ 130+ mph street driven, never, ever, trailered any where including drives up to Daytona.
Anyway the manifold works ;) Red,

What's the part # on the intake or is this a custom piece direct from Dart?

Thanks.

It`s a Dart deal top to bottom, one that is available OTC.
Call Dart, and ask them about the oval/rec conversion manifold.
I don`t have the PN right in front of me, but if you need it I can dig it up for you.

Give Dart a ring that should cover it.
I do believe we got ours from Doug.Herbert`s though.

So this might not apply if one doesn't have Dart heads?
Do youo have to send them a head to match to?
Ron

Sorry for going off topic here, but i've been wondering this for a long time.

What's the deal between Dart and World? Everytime i read something from more than a decade ago, they talk about Dart S/R Torkers, Dart Sportsman II heads and intakes, etc, and these are all names that World uses today. Anybody know what's up with this?

They were affiliated/partners at one time.

They mighta got "married" again recently too??

pdq67

Originally posted by Ron454:
So this might not apply if one doesn't have Dart heads?
Do youo have to send them a head to match to?
Ron Called Dart today. The part # for this manifold is 41214006 and is available through Summit Racing for ~$590. The ports are opened up to a Mr. Gasket 121 intake manifold gasket. The dimensions on the gasket are 1.75" W and 2.50" H.

Interesting..hmm..whats the Ždifference between the performer..and the performer rpm???...is it just the height of the plenum?