Notices
C3 Tech/Performance V8 Technical Info, Internal Engine, External Engine, Basic Tech and Maintenance for the C3 Corvette

Holley spreadbore on a 77

 
Old 01-24-2011, 11:25 AM
  #1  
0Paul Ruggeri
Former Vendor
Thread Starter
 
Member Since: Nov 2006
Location: Carmichael ca
Posts: 2,482
Thanks: 0
Thanked 1 Time in 1 Post
Default Holley spreadbore on a 77

A customer with 77 bought a Holley spreadbore for me to install. Its suppose to be a "direct replacement". When I tried set the carb on the intake, the vacuum housing hits the EGR valve. I called Holley and they said use a spacer. I'm concerned about hood clearence. Anybody running this combo? Any problems?
Paul Ruggeri is offline  
Old 01-24-2011, 11:29 AM
  #2  
wcsinx
CF Senior Member
 
wcsinx's Avatar
 
Member Since: Mar 2002
Posts: 23,120
Thanked 35 Times in 34 Posts
Default

remove EGR

install blockoff plate

problem solved

wcsinx is offline  
Old 01-24-2011, 12:23 PM
  #3  
0Paul Ruggeri
Former Vendor
Thread Starter
 
Member Since: Nov 2006
Location: Carmichael ca
Posts: 2,482
Thanks: 0
Thanked 1 Time in 1 Post
Default

Originally Posted by wcsinx View Post
remove EGR

install blockoff plate

problem solved

Unfortunately not an option here in California
Paul Ruggeri is offline  
Old 01-24-2011, 02:21 PM
  #4  
Cactus Dave
CF Member
 
Cactus Dave's Avatar
 
Member Since: Dec 2010
Location: Tucson Az
Posts: 92
Thanks: 0
Thanked 0 Times in 0 Posts
Default

Originally Posted by Paul Ruggeri View Post
Unfortunately not an option here in California
One of the reasons I moved to Az.
Cactus Dave is offline  
Old 01-24-2011, 03:05 PM
  #5  
jb78L-82
CF Senior Member
 
jb78L-82's Avatar
 
Member Since: Oct 2007
Location: Rhode Island
Posts: 6,243
Thanked 427 Times in 382 Posts
Default

Any way to put a spacer on the EGR valve itself instead of the carb? Just get through the inspection and then remove that sucker fast until the next inspection!
jb78L-82 is offline  
Old 01-24-2011, 03:23 PM
  #6  
0Paul Ruggeri
Former Vendor
Thread Starter
 
Member Since: Nov 2006
Location: Carmichael ca
Posts: 2,482
Thanks: 0
Thanked 1 Time in 1 Post
Default

Originally Posted by jb78L-82 View Post
Any way to put a spacer on the EGR valve itself instead of the carb? Just get through the inspection and then remove that sucker fast until the next inspection!
No, the EGR is under the vacuum housing, so spacing would make it worse. There is a factory spacer under the EGR, but even with that off it still hits. I think I'll just go ahead and space the carb up and see what happens. I'll post the results.
Paul Ruggeri is offline  
Old 01-24-2011, 03:34 PM
  #7  
birdsmith
CF Senior Member
 
birdsmith's Avatar
 
Member Since: Feb 2006
Location: Japan
Posts: 3,175
Thanks: 0
Thanked 0 Times in 0 Posts
Default

I had one on my '70 with no EGR (wouldn't have mattered anyway as it was a DP) but as I recall the airhorn was slightly higher on the Holley than the OEM QJet so I still wound using a different air cleaner base with a 2-inch (vs. stock 3-inch) thick air cleaner element. I have also used a 1/2 inch thick spacer on a previous motor (to adapt a square bore Holley 600 to a spreadbore intake) and noticed an immediate stumble when stepping on the gas...I'd say this is not a good combination for that particular car.
birdsmith is offline  
Old 01-24-2011, 03:37 PM
  #8  
snoopykissedlucy
CF Senior Member
 
snoopykissedlucy's Avatar
 
Member Since: Apr 2008
Location: Irving Texas
Posts: 593
Thanks: 0
Thanked 2 Times in 2 Posts
Default

My 1976 has a Qjet but interestingly enough....it has a super thick carb gasket...about 1/4 inch. I figured it was to prevent heat soak but it may be to raise it ever so slightly.

My local Autozone has this gasket in the carb rebuild kit. If you cant find it, use a Fel-Pro Q1908 1/4 inch gasket $12.99

snoopykissedlucy is offline  
Old 01-24-2011, 05:26 PM
  #9  
0Paul Ruggeri
Former Vendor
Thread Starter
 
Member Since: Nov 2006
Location: Carmichael ca
Posts: 2,482
Thanks: 0
Thanked 1 Time in 1 Post
Default

That's the gasket that came with the carb, not high enough. Got the spacer Holley recomended, clears the EGR, but now the hood hits the aircleaner, nice!
Paul Ruggeri is offline  
Old 01-24-2011, 05:32 PM
  #10  
Shark Racer
CF Senior Member
Support Corvetteforum!
 
Shark Racer's Avatar
 
Member Since: Jan 2000
Location: San Jose CA
Posts: 11,984
Thanked 99 Times in 93 Posts
Default

Paul, would a relocator help? I installed one on my 78 and can take photos.

The one I used rotates the valve 90* and about 2" towards the rear of the engine. Will PM you a link.
Shark Racer is offline  
Old 01-24-2011, 06:41 PM
  #11  
fauxrs
CF Senior Member
 
fauxrs's Avatar
 
Member Since: Nov 1999
Location: San Diego CA
Posts: 5,768
Thanks: 0
Thanked 1 Time in 1 Post
Default

Edlebrock makes an EGR offset that raises and offsets the EGR to clear various carbs, coincidentally it works with the Holley as well. I run the holley spreadbore on my car right now with the EGR and it clears fine using this part.

its a bit difficult to see but the EGR on my engine here is spaced towards the rear of the engine and up a bit using that item.

Last edited by fauxrs; 01-24-2011 at 06:46 PM.
fauxrs is offline  
Old 01-24-2011, 08:00 PM
  #12  
0Paul Ruggeri
Former Vendor
Thread Starter
 
Member Since: Nov 2006
Location: Carmichael ca
Posts: 2,482
Thanks: 0
Thanked 1 Time in 1 Post
Default

Thanks guys, looks like I'll be calling Summit in the morning.
Paul Ruggeri is offline  
Old 01-24-2011, 09:00 PM
  #13  
Shark Racer
CF Senior Member
Support Corvetteforum!
 
Shark Racer's Avatar
 
Member Since: Jan 2000
Location: San Jose CA
Posts: 11,984
Thanked 99 Times in 93 Posts
Default

Originally Posted by fauxrs View Post
its a bit difficult to see but the EGR on my engine here is spaced towards the rear of the engine and up a bit using that item.
Purdy motor. I put L-82 valve covers on my "L-48" and I stripped and painted them to look original. I like yours better, but it'd be hell-on-earth to clean up the castings I found to look like that... definitely factory.

Does that engine still look as pretty with all the smog dressings and vacuum hoses on top?
Shark Racer is offline  
Old 01-25-2011, 09:49 AM
  #14  
fauxrs
CF Senior Member
 
fauxrs's Avatar
 
Member Since: Nov 1999
Location: San Diego CA
Posts: 5,768
Thanks: 0
Thanked 1 Time in 1 Post
Default

Originally Posted by Shark Racer View Post
Purdy motor. I put L-82 valve covers on my "L-48" and I stripped and painted them to look original. I like yours better, but it'd be hell-on-earth to clean up the castings I found to look like that... definitely factory.

Does that engine still look as pretty with all the smog dressings and vacuum hoses on top?
Well I had mine chrome plated those arent raw aluminum of course
6 years later more or less yeah black paint between the chrome fins now . still its more cluttered to be sure.


Last edited by fauxrs; 01-25-2011 at 09:52 AM.
fauxrs is offline  

Thread Tools
Search this Thread
Quick Reply: Holley spreadbore on a 77


Sponsored Ads
Vendor Directory

Contact Us - About Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
 
  • Ask a Question
    Get answers from community experts
Question Title:
Description:
Your question will be posted in: