[Plenum] How hard to remove?

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Feb 14, 2003 | 11:04 AM

FlyboyZR1

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From: Minneapolis MN

[Plenum] How hard to remove?

I'm not expecting any huge gains, but I'd like to remove my plenum to have it ported and cleaned. On a scale of 1-10, how hard it the plenum to remove? It basically just looks like several torx bolts, a couple vacuum lines, and a brake booster fitting. I've heard many stories from forum members about stripping those bolts, and that's it's not worth it to remove it. Anyone have a step-by-step procedure, or should I just leave it alone?

:flag

Feb 14, 2003 | 11:31 AM

65Z01

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From: SE NY

Cruise-In II Veteran

Re: [Plenum] How hard to remove? (FlyboyZR1)

It's not realy difficult but I couldn't scale it for you.

There is also an electrical line to the MAT and the TB bolts to remove.

If you take your time and are careful you won't strip any bolts, just be sure to hand start all of them. The plenum usually requires a rap or two to break the seal to the runner flanges and some muscle to align all bolt holes on reassembly.

I don't think you will realize any performance gains from porting the plenum, though it was one of my first "free" mods.

Feb 14, 2003 | 01:08 PM

Jeffvette

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From: No more yankee my wankee, the Donger is tired!

Re: [Plenum] How hard to remove? (FlyboyZR1)

It's pretty simple

Remove Air bridge (black accordian)
Remove sensors (MAT, IAC, MAP, TPS)
Remove vacuum lines
Remove 8 rear most bolts
2 front bolts back off 1/4 inch and gently pull the plenum up (so you don't tear the gaskets) Pry gaskets gently off
Remove vacuum line on the underneath of plenum
Remove two clips for DIS
Remove the third clip in the bakc of the DIS module, then use a 1/4 rachet with a 1/4 socket to remove Another DIS harness
Pull plenum off

Things to check or do
Replace Vacuum lines
Check secondary actuators for binding
I would consider changing coil packs to Screamin Deamons
Tighten all bolts to factory specs

Figure about a 15 RWHP gain due to port work for the plenum AND injector housings. Look for a recent post in the ZR-1 section I just did regarding powder coating. Beware, has lots of pics.

Feb 14, 2003 | 01:47 PM

FlyboyZR1

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From: Minneapolis MN

Re: [Plenum] How hard to remove? (Jeffvette)

Quote:

Remove Air bridge (black accordian)
Remove sensors (MAT, IAC, MAP, TPS)
Remove vacuum lines
Remove 8 rear most bolts
2 front bolts back off 1/4 inch and gently pull the plenum up (so you don't tear the gaskets) Pry gaskets gently off
Remove vacuum line on the underneath of plenum
Remove two clips for DIS
Remove the third clip in the bakc of the DIS module, then use a 1/4 rachet with a 1/4 socket to remove Another DIS harness
Pull plenum off

Things to check or do
Replace Vacuum lines
Check secondary actuators for binding
I would consider changing coil packs to Screamin Deamons
Tighten all bolts to factory specs

Is that procedure for an L98 or a ZR-1? Despite my name, I actually have an L98. Thanks for the info though. :)

Feb 14, 2003 | 02:06 PM

VQT88Vette

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Joined: Jun 2000

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From: Las Vegas NV

Re: [Plenum] How hard to remove? (FlyboyZR1)

Quote:

Is that procedure for an L98 or a ZR-1? Despite my name, I actually have an L98. Thanks for the info though. :)

You should mention that in your original post...
All torx bolts are easy to stripped but the one you see on the plenum are easy. In order to take the plenum out you have to loosen the two bottom torx bolts on each side of the runner, that's is whe you may run into problem of stripped the head of the torx bolts because they are in an odd angle that you can't put a straight extension to it. Do it slow and you'll be OK, this is much easier than chnaging the spark plugs.

Feb 14, 2003 | 02:16 PM

Jeffvette

Race Director

Joined: May 2000

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From: No more yankee my wankee, the Donger is tired!

Re: [Plenum] How hard to remove? (FlyboyZR1)

Quote:

Is that procedure for an L98 or a ZR-1? Despite my name, I actually have an L98. Thanks for the info though. :)

Whoops ZR-1

Feb 14, 2003 | 06:59 PM

blk90rdstr

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From: Bucks county Pa

Re: [Plenum] How hard to remove? (Jeffvette)

It is relatively simple. I'll give it a 4 in dificulty. its the same procedure as the one posted maybe easier. Just remember to pull the vac and coolant lines off the throttle body as well as throttle/cruise/kickdown cables. The brake booster vacuum is hardlined you need to unsrew it, its easy to miss. Its pretty straightforward after. Some people say you need to tap it off with a 2 x 4 but mine pulled off easily. There is a list of good mods and maintenance to do while youre in there. Mine is apart right now all ported and polished.

Feb 14, 2003 | 07:34 PM

VetteNoob

Le Mans Master

Joined: Jan 2002

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From: Kyle TX (Because Mojo Made me fill it in)

Re: [Plenum] How hard to remove? (FlyboyZR1)

Real simple if you follow the directions you received (for L98s not ZR1s or you will be REALLY lost :) hehe). Took me about 30 minutes to take it off the first time and about 15 minutes there after. Go for it, it's fun anyways.