Plenum differences

Booyah

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Does anyone have some scoop on the differences between '96-'98 intake plenum and the '99 - '01 plenum? Key interest areas are performance difference if any and swapability of plenums between the two time periods. :read:
 

Booyah

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quadcammer said:
they won't swap. there is no use in swapping them even if you could.

That's all you've got, "they won't swap", followed by an opinion?

So why won't they swap? And one of the reasons I'm asking is because I hate the '99 - '01 plenum and would like to reuse my stock plenum if I decide to swap heads and intake.
 

Black96SVT

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how do you have a 99-01 plenum on when you have a stock 97 Cobra? :shrug:

you would need to change the heads and all that crap, not worth the effort and money
 

xxxcobra

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Black96SVT said:
how do you have a 99-01 plenum on when you have a stock 97 Cobra? :shrug:

you would need to change the heads and all that crap, not worth the effort and money

Actually if your staying NA it would be worth it, you would pick up some HP switching to a tumble port head along with a nice 99-01 ported intake.

I will be doing this swap (04 cobra heads) when money permits.
 

Booyah

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:p
Black96SVT said:
how do you have a 99-01 plenum on when you have a stock 97 Cobra? :shrug:

you would need to change the heads and all that crap, not worth the effort and money

I think you need to reread what I typed. I never said I have a '99 - '01 plenum. I stated I have a stock plenum and don't want to use a '99 - '01 plenum if I decide to swap heads and intake.

Reading it's fundamental. :p
 

blackfang

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The C head engine aka 99/01 Cobra has a tumble port head design unlike the B heads. In order for the intake to bolt up you need the C heads unless you want an amazing loss of hp. The ports of the B heads do not match up with the intake. Plus a tune will be needed to eliminate the IMRC's.

Tumble port gives a more violent explosion in the chamber and gives more low and midrange power over the 96-98's. The B heads flow better, but lack in velocity where the C heads shine in that catagory.
 
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Booyah

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blackfang said:
The C head engine aka 99/01 Cobra has a tumble port head design unlike the B heads. In order for the intake to bolt up you need the C heads unless you want an amazing loss of hp. The ports of the B heads do not match up with the intake. Plus a tune will be needed to eliminate the IMRC's.

Tumble port gives a more violent explosion in the chamber and gives more low and midrange power over the 96-98's. The B heads flow better, but lack in velocity where the C heads shine in that catagory.

See this is the info I already have but what's the difference in the plenums between the setups. Being that the plenum is just a cover for the intake does the '99-'01 plenum help with velocity?
 

na svt

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blackfang said:
The B heads flow better, but lack in velocity where the C heads shine in that catagory.

The B-heads do not flow better than C-heads. They are the worst flowing stock 4v heads available. And yes, they also lack velocity.
 

na svt

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Booyah said:
See this is the info I already have but what's the difference in the plenums between the setups. Being that the plenum is just a cover for the intake does the '99-'01 plenum help with velocity?

The upper intakes are not interchangeable.
 

quadcam

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Ok, I intend to go FI in the near future, would the SHM short runner intake for the B head motor be a good mod for n/a? Would it get gains, or would the bottom end loss make it not worth it?
 

na svt

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quadcam said:
Ok, I intend to go FI in the near future, would the SHM short runner intake for the B head motor be a good mod for n/a? Would it get gains, or would the bottom end loss make it not worth it?

A standard short runner intake will not kill your bottom end. It will barely be noticeable especially if you have 4.10s or steeper gears. Supercharged on 3.73s will be okay also.

Don't get the shm short runner, you can make one yoruself or have someone do it for you. I'm making one now.

Short runners are good for about 20-25 hp at peak and will work with both FI and N/A.
 

xxxcobra

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na svt said:
A standard short runner intake will not kill your bottom end. It will barely be noticeable especially if you have 4.10s or steeper gears. Supercharged on 3.73s will be okay also.

Don't get the shm short runner, you can make one yoruself or have someone do it for you. I'm making one now.

Short runners are good for about 20-25 hp at peak and will work with both FI and N/A.


I agree, make it yourself an save $$$
 

quadcam

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Are there any threads on how to do this? I am ok at wrenching things, but I dunno about machine work....

edit- would I do well to delete the IMRC while I'm at it, or should I hang on to 'em till I get the blower?
 

xxxcobra

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quadcam said:
Are there any threads on how to do this? I am ok at wrenching things, but I dunno about machine work....

edit- would I do well to delete the IMRC while I'm at it, or should I hang on to 'em till I get the blower?

I would delete them.
 
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