Bigtime
Well-Known Member
I need that dual plane intake!
600 or 750 CFM?
- Thread starter Bigtime
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Bigtime
Well-Known Member
Like to have it, but it is too pricey for me right now...Gonna have to save some $$$. Also, a new Performer RPM is about $75 less isn't it?
Bigtime
Well-Known Member
Good advice....I will check out the AFR. I am a believer in only changing ONE THING at a time. I got that from the bracket racing days. Change one thing, TEST IT, and continue to change as desired. I am also a believer in spacers and have a NIB 1" open plenum one in the garage. I will use my current setup as a base line, THEN I believe that I would 1]try the dual plane and the 600, 2]try the dual plane with the 1" spacer with the 600, 3]try 1 & 2 with the 750. This should tell me what I want to know...I hope.
Bigtime
Well-Known Member
Another thing to throw into the mix here. I believe the car has a 3.23 gear in it now. I will have to get an idea using the "chalk" method. I have a 4:11 for the car. In my opinion, when I put the lower gear in the car I will test it with my current setup. The lower gear may make the TM6 work better since the engine will operate [theoretically] at a higher RPM range. If the engine seems [then] starved, the 750 with the TM6 may be the hot lick. Won't know until the gear is in the car, then I can start testing different things.
Bigtime
Well-Known Member
I will try the AFR gauge....and BTW, to ALL who are responding to my post: If I MISS responding to you I apologize. I've received SO MANY good responses!
Mopar Muscle carburetor shoot out article,puts the hp numbers to cfm's. Article is based on a 383/906/500 lift cam.
https://www.hotrod.com/articles/mopp-1207-carburetor-dyno-test/
https://www.hotrod.com/articles/mopp-1207-carburetor-dyno-test/
Dibbons
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Thanks for the article. Sad those dyno pulls don't represent driving around town or part throttle getting on a freeway on ramp.
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I'd swap to a dual plane. You can sell the TM-6 to recoup some money.
Carburetors and climate change, every one is an expert LOL...I have heard this song way to many times, your running what... oh your carb is to large... get a grip....
My car, in avitar, 383, 727, 323...built to stock specs, TRW flat tops, 460 lift purple shaft and 906 heads and a holley dominator single plane. Built the car for a client 30 some years ago, so, it was kept tame. He returned the car a year later, and, it never left. A sales rep at a local Dodge dealer supplied all parts required, and with that said, a 625 cfm carter was supplied. I put the car away for 15 years, finally had some time to spend on it, so out it came. And just as I had remembered, way soft on response. Off went carter, pulled a Holley 780 VS off the shelf ( 780 = 350 Z28) and bolted it on, instant game changer.
My car, in avitar, 383, 727, 323...built to stock specs, TRW flat tops, 460 lift purple shaft and 906 heads and a holley dominator single plane. Built the car for a client 30 some years ago, so, it was kept tame. He returned the car a year later, and, it never left. A sales rep at a local Dodge dealer supplied all parts required, and with that said, a 625 cfm carter was supplied. I put the car away for 15 years, finally had some time to spend on it, so out it came. And just as I had remembered, way soft on response. Off went carter, pulled a Holley 780 VS off the shelf ( 780 = 350 Z28) and bolted it on, instant game changer.
Breaking the threads up a bit here..for fear of wall of text LOL
Second thing to be changed out was that single plane domonator,for a RPM duel plane, again seat of the pants change, yeah, almost filled my pants with crap, when my car got sideways after a launch...
So,Duel plane for sure, as for carb size, as the above article shows, more fuel ,more power,. And for the neh sayer's, think about a 340 six pack, how many cfm's there, to some folks here, they would say, there is enough carburetor for two engines!!!!!!
When you understand how the 6 pack, 6 barrel works, things will make better sense.
As for the smelly carb guys, adjust your idle mixture screws, should solve the problem.
Second thing to be changed out was that single plane domonator,for a RPM duel plane, again seat of the pants change, yeah, almost filled my pants with crap, when my car got sideways after a launch...
So,Duel plane for sure, as for carb size, as the above article shows, more fuel ,more power,. And for the neh sayer's, think about a 340 six pack, how many cfm's there, to some folks here, they would say, there is enough carburetor for two engines!!!!!!
When you understand how the 6 pack, 6 barrel works, things will make better sense.
As for the smelly carb guys, adjust your idle mixture screws, should solve the problem.
Lazerwolf
Well-Known Member
Agree with everyone here, no exact answer but go with dual plane. I have a similar engine, 400 (EStreet heads), mild cam (Lunati voodoo 10230702). When purchased, it had a performer RPM intake and 600 Edelbrock carb. Ran like crap, either bogged low end and/or choked under hard acceleration. Edelbrock tech said intake doesn't match heads so go with performer instead of RPM, which helped with my configuration. Biggest difference was switching 600 Edelbrock for 750 Holley. Not saying the switch from Edelbrock to Holley was the answer, but I had a Holley so that's what I used. I had called both Edelbrock and Holley, which both said the 600 should have been good enough. Very happy with the way it runs now. AFR meter says running a bit rich but my configuration seems to like that. Seems sluggish leaning it out more.
Bigtime
Well-Known Member
I'm inclined to try your suggestion....I have a 750 Edelbrock carb rebuilt in the box, and by selling the Tarantula intake that is on the car along with a Torker that I have laying around I can buy a Edelbrock RPM intake. The only question that I have now is how [do you think] the 750 + an RPM intake will work with a 4.11 rear gear....I think I'll be just fine....WONDER WHAT others following this thread think??
Woah!!!!!!
Your original post was 383/727/323 set up. Because you and I were running a 323 gear, and with out a torque converter, a single plane manifold would not create enough lower end torque to get our cars up and moving. If you have a 411 gear, now, leave the single plane on and check out the 750 you have in stock.
Your original post was 383/727/323 set up. Because you and I were running a 323 gear, and with out a torque converter, a single plane manifold would not create enough lower end torque to get our cars up and moving. If you have a 411 gear, now, leave the single plane on and check out the 750 you have in stock.
Bigtime
Well-Known Member
I'll do just that, and thanks! I was thinking the same thing. Since I am going to run the 4.11 rear gear FOR SURE, I should check performance with my existing set up. [with the 750 carb, not the existing 600] It's obvious that the lower gear will cause the motor to wind up faster and operate in a higher RPM range. This is a "stoplight" car for me.....weekend fun...no racing or constant high RPM's. I will give it a try with the 750 carb once I have the center section in place.
Bee1971
Well-Known Member
"This is a "stoplight" car for me.....weekend fun...no racing or constant high RPM's."
Just an observation
Then why are you so stuck on a single plane intake manifold , especially on a mild build 383 ?
As others have stated - Dual Plane Intake on the street where TORQUE is it for everyday driving , stoplight to stoplight
Lower Gearing will help
But under 3,500 RPM s , a Edelbrock Performer / Performer Rpm TORQUE will bee night and day difference compared to a single plane
Especially
"This is a "stoplight" car for me.....weekend fun...no racing or constant high RPM's."
Just an observation
Then why are you so stuck on a single plane intake manifold , especially on a mild build 383 ?
As others have stated - Dual Plane Intake on the street where TORQUE is it for everyday driving , stoplight to stoplight
Lower Gearing will help
But under 3,500 RPM s , a Edelbrock Performer / Performer Rpm TORQUE will bee night and day difference compared to a single plane
Especially
"This is a "stoplight" car for me.....weekend fun...no racing or constant high RPM's."
Bee1971
Well-Known Member
I would say your engine is quite a bit different then O.P. especially running the E Street Heads and Cam
What CC ?
Anyways , yes I could see it choking or falling on its face running only a 600 cfm carb , probably very lean under load with your configuration
I would say huge difference changing to the Holley 750
But I had to laugh at the Edelbrock Tech
Man talk about that Tech reading from his little go to script
Let me guess - Script says
E Street Heads = Performer Intake
Performer Heads = Performer RPM Intake
When in fact the E Street Heads flow identical to the Performer Heads - Difference is the valves and valve seats themselves and different CC configuration on what head you buy
Nothing wrong with the Performer Intake but
The Performer RPM is about as good as it gets best option for street use running those heads
Only issue with the RPM is hood clearance if you don’t have it
If you still have the RPM intake , hood clearance is not an issue, swap it back out again running that Holley 750 on top
You might bee surprised
The carb shootout, went in hand, with the manifold shootout, round 1 and round 2. The second round sold me on the RPM, 1st round had me hunting down a DP-4B. Had already changed out the 906's for a set of Stealth's.
All of these tests were done on the same motor, this was their test mule. I have the original copies that had these tests in the archives. At the end of the carb shootout,while the motor was still on the dyno, for shits and giggles, the started removing loads, alt, water pump, etc. The last thing they did was change the oil.....20/50 to..... 5/30 viscosity,
I was shocked to see that HP gain!!!!!!
https://www.hotrod.com/articles/hrdp-0712-mopar-intake-manifold-comparo/
https://www.google.ca/search?source...-wiz.....0..0j0i131j0i22i30j33i21.wfXVjRfLEDE
All of these tests were done on the same motor, this was their test mule. I have the original copies that had these tests in the archives. At the end of the carb shootout,while the motor was still on the dyno, for shits and giggles, the started removing loads, alt, water pump, etc. The last thing they did was change the oil.....20/50 to..... 5/30 viscosity,
I was shocked to see that HP gain!!!!!!
https://www.hotrod.com/articles/hrdp-0712-mopar-intake-manifold-comparo/
https://www.google.ca/search?source...-wiz.....0..0j0i131j0i22i30j33i21.wfXVjRfLEDE
Last edited:
BSB67
Well-Known Member
I'm not sure which carb shoot out you are referencing. The carb shoot out article from above is dated 2012 and manifold shoot out 2008.
Here is my cautionary note to the lovers of the RPM intake. No manifold does everything the best. And 383s are not 440s. IMO a 1 hp/cuin street driven 440, will probably be best suited with the RPM, a 1 hp/cuin 383 will probably be better suited with a Performer, or other dual plane intake IMO.
In Shoot Out 1, the 383 was making over 450 hp, and the RPM intake slightly out performed the other aluminum dual plane intakes in the upper rpm range, and about even or slightly under performing in the lower rpm range. Personally, in shoot out 1, I would pick the RPM if that was my 450 hp 383. But in reality there are very very few stock stroke 383 making anywhere near that power. That motor in SO1 had 10.3:1 CR, light weight diamond racing pistons, a medium size cam with the most aggressive racing solid flat tappet lobes made by Comp Cams. It is highly unlikely an inherited "mild" 383 will even be close to 400 hp. That, coupled with the fact the short stroke 383 struggles with low end torque, I would generally give the nod to one of the other dual plane intakes.
Lazerwolf
Well-Known Member
Sold the RPM. The extra roughly 1 1/2" extra height on RPM with a 1" spacer, had the hated Edelbrock 1002 bug eye cleaner hitting the hood. Without the spacer, the 600 carb was terrible to start warm. Never tried the 750 without spacer, probably should. First swapped out the RPM for performer and put normal air cleaner on. Better but not happy. Swapped out the 600 for 750 and performance much better. This might try removing the spacer and it no issues, could consider going back to a RPM intake.
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