i have been doing some research on simple bolt on mods to open up the flow of the plentum some options i have seen are spacers between the top plentum and the bottom one but that seemed very contravercial as to just a increace of power on the bottom end and i really would like more responce but i dont wont to loose top end power, but i didnt find any thing on how high in the power band the power is effected due to lenthening the runners. i also was looking for the diference in the 2.8 plentum and a 3.1 plentum (being more open) if there is a diference besides the abcense of the 2.8 madlion. PS this is on a v6 that has had a 3.4 swap and still has all the 2.8 intake and fuel sys. Thanks

any advice/threads on this is apriciated

 

2.8/3.1 intakes are the same internally

 

okay thats what i thought, you know anything about the plentum spacers?

 

money better spent would be having the 3.4 intake modified to fit with the distributor, it takes 2 saw cuts and a tiny bit of welding to make it work. welding shop prolly charge u about 40-60 bucks to make the cuts and weld it up

 

and keep the 2.8 plentum?

 

Any pictures of the modified 3.4 intake so i can use a distributor with my future swap.

 

the front side of the 3.1 plenum has to be modified to accept the 2.8 Throttle body

I can post a pic of the two side by side if you are interested. I have them both right here next to each other

 

on both these pics, the 3.1 plenum is on the top.

it's the only differences I can find.

 

I take it by this you know what I was about now, with clearancing for the TB? And as dave said, they are identical internally, spacers would help, but not hugely, a 3.4 intake takes more work to make work than it seems like it would at first glance, even figuring out how to run the throttle cable is a pita...

 

Yep! I didn't know they used different tb's, but after looking at them, it's no big deal to alter it

 

so to replace the intake not the plentum it just two cuts for the distuributor and the 2.8 plentum will bolt right back up?

 

send pilsbury a pm he has the 3.4 intake modified to fit on his car

 

I have a full 3.4 intake over here that I got with my 3.4 engine... now i'm interested in the procedure to make it work

 

u pretty much have to cut the crossover tube off the back of it and then weld up the holes. other then that i think u just need the throttle cable and bracket from a 3.4 car. along with the tb

 

yeah, I read up on a lot of old threads that covered that, and even found some pics.

Not sure it actually DOES anything positive, but it's a cool idea. I guess I'll just polish up my 3.1 plenum when I swap to the 3.4

 

its a much better intake, it has a larger plenum volume, shorter runners, and no nasty bend in it.

my only concern would be in a boosted application, on pilsburys car the middle cyl on the driverside was running hotter then the other 5( about 100* iirc), i dont know if this was an airflow issues or the injector was running a lil leaner in that cyl, i didnt have enough time to look into it while i was there doing the turbo stuff on his car

im pretty sure the one injector was just flowing less then the others and was causing the issue, cause to be honest if any of the cyls should have been lean it should have been the rear cyls since the air would stack up at the back of the intake making the rear cyls being fed more air

 

even with the back rail of the plenum scooped out, it still practically hugs the distributor cap. I'm wondering what kind of effect that much heat would have on the electronics

now, if you go full bore and put the coil packs in there... it might be more attractive to me

 

the heat wont hurt it,just make sure there is dielectric grease under the ignition module and u wont have any issues. i modified a gen 2 fwd top end to clear a dizzy and the guy never had an issue with it. that had 1/16th clearance from the dizzy to the back of the intake

 

well, I've got the plenum, so i guess there's no hurry to decide what to do with it.

how do I get around the Throttle cable problem? couldn't find much info on that

 

sorry., missed this post. So putting the cable and bracket from a 3.4 solves the problem?

which TB do I use?

 

+
i would assume the 3.4 bracket and tb would be the way to go,u would have to ask pilsbury for the definative answer as he is the only one i know of currently using a 3.4 intake on his motor