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I have used all the mentioned intakes on my 302 in a 84 Mustang. Had the T5 with a 3.08 rear. Cam was a .536/.548lift heads pocket ported DOOE. Both 650 and 750 Holley carbs used.
The Vr Jr was slightly lower on torq but just enough to make it easyier to drive around town. Mid range and top end was better. I have also flow tested each of these intakes bolted to several SBF heads factory ported and aftermarket ported.
I pulled 24 to 28 MPG highway with the Vr Jr. Dont remember in town. The 750 did well untill a muffler shop doing my exhaust screwed up the tube size going over the rear axle. Had to drop to the 650.
If I had dug into it deeper at the time I would have noticed the Jr port is raised around .1 of an inch over stock location (the Vr EFI is about .285 over stock location). Could turn average of 12.2 in the quarter.
On the bench all of the intakes reached max flow around .500 lift.
Wether the combo works or not mostly depends on selecting all the correct parts. Very important is being able to modify each circuit in the cab to function correctly. Most only change main jets possibly the power valve.
 

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Discussion Starter #22
Thanks for the responses. Seeing I am going to change the manifold anyway, I will be going dual plane. Most likely a RPM AIr Gap. According to Edelbrock Tech, my hesitation while easing the throttle is the manifold. Caused by the large plentum and the exhaust gasses being drawn through the cyl. in the overlaping phase. This causes rough low RPM running. Their words, not mine. They said that when I tromp it (which I get no hesitation) it rushes more air down the cyl not giving the exhaust gases enough time to draw through the cyl. With a dual plane the passages and plentum are smaller and the air going through has more velocity at lower RPM, therefore more low end power and torque.
 

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The real issue might be the port volume of the heads. If they are too large the air velosity is screwed causing poor filling of the cylinders. The cam selection can aggrivate the issue. Split lift and overlap the big contributor.
Many of my builds have higher dynamic compression than static. This is because of more effective filling of the cylinders. A dual plane will possibly in most cases bandaid your issue.

But then you will have what I concider a cammed motor which most manifold companies condone
 

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Thanks for the responses. Seeing I am going to change the manifold anyway, I will be going dual plane. Most likely a RPM AIr Gap. According to Edelbrock Tech, my hesitation while easing the throttle is the manifold. Caused by the large plentum and the exhaust gasses being drawn through the cyl. in the overlaping phase. This causes rough low RPM running. Their words, not mine. They said that when I tromp it (which I get no hesitation) it rushes more air down the cyl not giving the exhaust gases enough time to draw through the cyl. With a dual plane the passages and plentum are smaller and the air going through has more velocity at lower RPM, therefore more low end power and torque.

The tech got it right. A single plane CAN be streetable..depending on your personal interpratation of streetable...Generally speaking, it's not a low RPM performer.
 

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The real issue might be the port volume of the heads. If they are too large the air velosity is screwed causing poor filling of the cylinders. The cam selection can aggrivate the issue. Split lift and overlap the big contributor.
Many of my builds have higher dynamic compression than static. This is because of more effective filling of the cylinders. A dual plane will possibly in most cases bandaid your issue.

But then you will have what I concider a cammed motor which most manifold companies condone
imposible to have higher dynamic c/r than static .
filling the cylinders is different than ratio's

I know what your saying ,

YES , an engine can have Higher cyl. psi at 10/1 cr that one with 12/0cr
 

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Thanks for the responses. Seeing I am going to change the manifold anyway, I will be going dual plane. Most likely a RPM AIr Gap. According to Edelbrock Tech, my hesitation while easing the throttle is the manifold. Caused by the large plentum and the exhaust gasses being drawn through the cyl. in the overlaping phase. This causes rough low RPM running. Their words, not mine. They said that when I tromp it (which I get no hesitation) it rushes more air down the cyl not giving the exhaust gases enough time to draw through the cyl. With a dual plane the passages and plentum are smaller and the air going through has more velocity at lower RPM, therefore more low end power and torque.
edel. tech is half right , know what that means for the other half
 

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imposible to have higher dynamic c/r than static .
filling the cylinders is different than ratio's
Nope. DCR "can" be higher than static. intake manifold pressure also affects DCR-in a big way. In the wallace racing calculator, put in 30 psi boost and see what the DCR goes up to. I've seen them upward of 35:1 DCR-but we're talking 2000+ HP boosted engines.
 

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Nope. DCR "can" be higher than static. intake manifold pressure also affects DCR-in a big way. In the wallace racing calculator, put in 30 psi boost and see what the DCR goes up to. I've seen them upward of 35:1 DCR-but we're talking 2000+ HP boosted engines.
nope , DCR , isn't PSI . .DCR is just a ratio , that's what the R stands for
 

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nevermind. Arguing has absolutely nothing to do with the original post. My apologies for hijacking. I will no longer share my experiences since Mr DANH can't post anything that makes sense.
 

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nevermind.

Arguing has absolutely nothing to do with the original post. My apologies for hijacking.

I will no longer share my experiences since Mr DANH can't post anything that makes sense.
I am glad I am not the only one that cannot understand mumbles... :frown:

I have him/her/it/mutant on IGNORE. Did he ask you for any and all hands-on experience? :confused:

 

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nevermind. Arguing has absolutely nothing to do with the original post. My apologies for hijacking. I will no longer share my experiences since Mr DANH can't post anything that makes sense.
mavman do the math to prove me wrong.
that would make the klutz life worth while .

you don't understand or it makes sense , because you don't know the differene .

here is some help understanding ..... when doing the DCR , is the intake manifold pressure info ask for ?

anyone can post up what the DCR is and how its got
 

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I am glad I am not the only one that cannot understand mumbles... :frown:

I have him/her/it/mutant on IGNORE. Did he ask you for any and all hands-on experience? :confused:

klutz , can ask you about anything and you wouldnt know , except for cut and paste / links .

btw , does your foot taste good or hurt ? maybe both ?

ADD.. klutz this could be your dream come true , you can cut & paste what DCR is and and do an example. no ,not you do an example but cut & paste one

klutz , I know the ignore button isnt working , dont miss your chance
 
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