Testing the 3500 Plenum.

[v6h.o.]

finally got off my lazy ass today and installed this thing after its been sitting around on my shelves since about May or June...

I started modding it to fit a few months back but just never got the time to finish mod'ing it to make it work. Quite a bit of modd'ing went into it just to get it to fit on the car as is anyways. PITA GM changed a few things on this engine which makes it not such a direct bolt on due to items hitting/contacting others. even though it does bolt onto the LIM directly as the 3500 shares the same LIM as the 3400's do.

its half-ass'd on there right now just to test it out see what it feels like, will need to redo alot of shit. but for now i just wanted to see(feel) what it was like, find any problems maybe or what i need to change to get it on there for next year. It does by seat of pants dyno feel a bit better top end wise. but its hard to tell really. In theory it should be better for High RPM power anyways. but proof is only in the pudding as they say. wish the track was still open. Should have had things more organized to test this thing back when i went to Saskatoon, who knows might have seen another tenth less... maybe not.

few shots of the ugly bitch (looks like a Gen2 and Gen3 plenum had sex and this is the offspring) i did start to sand it down, will eventually polish it up as well.










The 3500 doesnt use a FPR on the Rail it uses one in the Fuel sender unit in the tank so of course it hits the 3400 FPR at its widest point... just clears it now.

[Guest]

sweet nice work.

I say you hit a dyno instead of a track. A track can have different conditions at different times of the day. A nice back to back run on teh dyno when you have it all sorted out to make an easy swap to the next intake would be a good way to do it.

or dyno it, and try and get back as soon as possible and then redyno it and use the SAE numbers.

Good work. I would rather use this over a 3100 or 3400 intake as it will give more top end(theoretically) and it also doesnt' haev all the numbers on them. Cleaner look I think.

Shaun

[ProjectMM]

Sweet, hope it helps! how much time did it take to bolt on? and get running?

[gpse3400]

Do you think you could please give the what for on the TB mounting?

[Rhedalert]

Do I see just 4 bolts for the plenum-to-lower?

[v6h.o.]

No there is 6 bolts. in the pics you cant see the one by the P/S pump front corner as its an old original black 3400 bolt.

they are all in the same location as the 3400 plenum as per bolting.

for the t/b i bolted it up just using 2 of the 4 holes that are already existing in the plenum, just instead of worrying about the locations and redrilling for the proper stock 8MM bolt holes, i used the small pre-existing holes and two small 6mm bolts. Just Fit, some anarobic sealant on the t/b and that solves the gasket issue. LOL.

the problem with doing this as you might see in the pics is the T/B cable bracket does not completely work at all really now. this bracket is a one off one that i have as I made it years ago when i did my top end conversion and used the wonky 2.3L DOHC throttle body (stock it was 56mm, and at the time it was the largest t/b i had kicking around to use, this has since gone from stock 56mm, to overbored 60mm, to now its existing 64mm diameter-Waffer thin!) the bracket only bolts up to the t/b on the one bolt hole on the front of it. the two stock style throttle body bracket bolts that go on the top of the bracket into the plenum on the stockers are not able to be used, and since i just half ass'd this t/b on with the two bolts its on an angle that makes the bracket sit even more wonky..

things i had to do to even get it bolted on:

Grind down the area for the FPR to clear,
Cut down the bolt hole for the #2runner at the P/S pump to plenum area as on my application (stock 3.1L front cover modified to fit GEN3 P/S pump it tilts the pump and twists it more forward compared to gen3 front covers do, which i had issues with the 3400 plenum fitting this way as well)

I cut off the EGR and Purge Valve Ports at the back of the t/b opening area due to fitting my T/B on as well as i dont use any of these ports on my 3400 either. (the Holley doesnt alow for EGR or Purge valve control either)
these were cut off flush at the t/b neck and then for quick testing purposes filled with High Strength/Cure Bodyshop epoxy, its a black thick goo that turns hard as a rock. -i've used it in the past to seal a cracked Transfercase for customers.

I also had to grind areas of the T/B flange to alow my wonky setup t/b to be able to move through the paces as the arm was hitting the flange in one small spot.

the IGN module on the3500's is different to our older stuff. so the bolt holes are way off in alignment. the Ign module is just bolted to the plenums two bolt holes but not the back two studs for now.

other than that, its a direct bolt on replacement :P

pics of it when i got it out of the box:

[RednBlack]

Fucking Canadians! (Unless you are French Canadiens) Snows so much, all you can do is work on your car! No time for BBQ and Deer Hunting! All you do is work on the Damn car and bitch about our politics! btw....Excellent work Colin! :P

[gpse3400]

Hey Colin, what was the part number of the Upper intake and the price?The Canadian figure will be fine.

[v6h.o.]

part number is:




I payed $175 bucks Canadian for this, but that was at my price through work.

[FastGT31]

just to let everyone know, at GMPARTSDIRECT.COM that piece is only $116.99 U.S shipped to your door. international shipping may be higher

[Chris88CL]

GMparts direct doesnt ship to Canada unless they have recently changed their policy

[Mars]

Nope they dont ship to Canada

[Batman96LS]

so why should this give more topend?

[bszopi]

Larger plenum volume.

[RacerX11]

Larger plenum volume.

And slightly shorter runners

Marty