Cookwithvette

I just took the carb off and found a couple drilled holes in the passageways of my intake manifold. I can't remember if they were there from the factory or not. Has anybody seen anything like this?


http://temp.corvetteforum.net/c3/coo...tte//holes.jpg For large image.


[Modified by Cookwithvette, 7:43 PM 3/23/2003]

BSeery

hmmmm-- don't remember seeing those on mine. I don't plan to pull my carb off for a while either.




[Modified by BSeery, 12:34 PM 3/23/2003]

theandies

I can't recall seeing any either. I'm like Brian though, not planning a carb change soon.

CDaniel525

well I am pretty sure they are there on my manifold as well not sure what they are for tho
best bet would be go to salley-chevrolet website and ask in their forums....people who work there will respond with a definite answer
orr just call them :cool:


[Modified by 74VETTE, 8:51 PM 3/23/2003]

QuickVet

i have one on the shelf at home. i will try to take a look for you tomorrow and let you know.

Smokehouse69

Mine had 'em, I was shocked when I saw them, so I called Jim Pace. The techs said they were supposed to be there. What purpose they serve, I have no idea.

Mystery Machine

Never even noticed when I swapped carbs a few weeks ago :conehead

Kinda strange though... :skep:

Paul 75 L82

They act like a built in PVC valve. They suck from the lifter valley into your intake and relief any backpresurre that the motor creates. It's a smog thing!

Cookwithvette

The holes don't seem to go down into the oil galley. In fact, the left hole still has a large puddle of gas in it. I'm beginning to suspect they are outlet holes for EGR functions. I know the ZZ4 doesn't have EGR capability because of the heads but that manifold supports such function.

Cookwithvette

Smokehouse69: This is good to hear. They looked so.... Bubba. I started rolling on the floor when I saw your sig. "Always where under where." :lol:

QuickVet

I checked my manifold. it too has these holes.

Twin_Turbo

That's not possible. Having an air leak there would mean you have almost no throttle control over the engine rpm by altering the amount of air coming in. Air would be sucked in via the valley and the breathers on the valve covers.


[Modified by Twin_Turbo, 5:53 PM 3/24/2003]


[Modified by Twin_Turbo, 2:53 AM 3/25/2003]

Cookwithvette

Thanks QuickVet

cardo0

Saw nearly the same thing on a brand spanken new Edlebrock Performer with EGR that cost me ~$150. Verified with a fashlight in dark room they'r feed by the EGR valve which is plugged off in your pix. Didn't like the idea as possible fire hazard from raw fuel - Murphy's law ya know. Sent that intake back. :(
You could just thread and plug (with pipe plugs) but should really remove intake to keep any metal scraps going you know where.
My Shark needs a C.A.R.B. exempt intake and the Weiand #8000 is my next victim. :yesnod: Pix on Holley (new owner) website looks good (no holes).
BTW those wheels are good match on your color shark. :thumbs:

Cookwithvette

Thanks cardo0. :cheers:

My biggest concern now is how to get the lake of fuel out of that passageway. You can see gas in the left hole in the pic. (Really scared me, looked like coolant at first) I've been planning to go EFI for some time now so if/when that manifold comes off it won't be going back on.

BSeery

Looks like a damn good place for some JB Weld !!

cardo0

Just removing that EGR bolck plate should allow a dain path and If you have an air compressor blowing air would help dry it out - also verify connection to EGR. The ZZ4 aluminum heads don't have an exhaust crossover port making the EGR valve pretty stupid.
I like BSeery's idea to seal with a blob of JB weld - easy fix. :thumbs: