Hello - my nailhead is running again and I had a great drive through the black forest. This afternoon I decidet to take off my old rochester and put my new edelbrock carburetor with the edelbrock spacer on. Like you can see in the picture , my spacer holes and manifold holes do not really mach in the seize. Is that usual ??? The spacer is a original edelbrock spacer for my 401 nailhead. Also another question: you can see the red arrow - it points to one of two holes in my manifold. What are thouse holes for - and where do they go to??? There is also a connection between those holes. When I put my spacer and carb on , should I install the gaskets dry and what torque should I put on the screws? Ok - thank you for your help - Herby from far away black forest / Germany
The holes you've pointed to are an exhaust passage. This is there to help warm the carb for cold operation. Working with these is a pain because there's supposed to be a steel shim gasket that covers this passage before the regular carb base gasket is used...this protects the carb from the corrosive exhaust gases. Might not be an issue since you plan to use the adaptor which will protect the carb. Devon
Hi again ! So - could I just put my new carburetor on the manifold ? Is the spacer just for going from spreadbore to squarebore ? Should I close the holes from the exaust or just let them be as they are? Thank you for your help !!! Vielen Dank auch an Sascha aus Hannover - was meinst Du - kann ich also die Adapterplatte einfach weglassen , wenn beides squarebore ist ??? Gru aus dem Schwarzwald - Herby
Your manifold looks like the old square bore pattern, but your spacer looks like one side is for a spreadbore (small primary bores, large secondaries). Does the carb have the same pattern as your manifold (squarebore)? If so, you can either block the exhaust passage completely (see here: http://www.v8buick.com/showthread.php?t=128085 ) or use the original heat shield gasket, and avoid the spacer. Either way you have to make sure you protect the carburetor from exhaust gases. Devon
Out of curiosity, what would be a good source for the heat shield gasket? When I put my Edelbrock 750 on, I just bolted it on and ignored this passage. After reading this, it seems like that was probably a mistake. Thanks, Mike
I'm afraid I can't help you there, you might want to start a new thread to get the attention of those who know. Devon
Herb,, What you really need to do is put a spread bore manifold under the qjet that you have. A spread bore with adapters under it is not good. like tryint to cram a tornado thru a key hole. Put a spread bore manifold to match the carb and you should get a big performance boost.
I think you will be ok just putting the new Edelbrock carb directly on the stock intake. Do not try to use the spacer as the front butterflies/valves will not be able to open in the small quadrajet style holes in the spacer. Edelbrock offers steel heatsheild type plates. You would need to use a gasket on top and bottom of the spacer though. I would use the new Edelbrock carb, and do some slight reworking of the stock intake. I think both Doc, and Telriv (Tom) have posted some modifications that would help you get more performance out of the stock intake.
Mike - try this link http://www.oldbuickparts.com/commerce/product_info.php?cPath=19_31&products_id=1192 If that dont work - oldbuickparts.com go to 63-85 riviera parts, then group 3, part is carbuerator baffel plate 14.95
One of the guys on the nailhead list has recently made some very nice carb 'heat shields'. He has done the Carter AFB/Roch 4 CG square and will soon be doing for the early Qjet base. They are stainless and three times thicker than the old stocker=a perfect fit and very nice. I'll post when those are available-
Hey Doc. The 66 parts book does not show a gasket between carb and stainless plate. How would the heat get to the carb if you insulate it from the carb?
