ERICCAMARO

I have a pre 87 base with post 87 heads What do I have to do to the lower intake base to make it fit the late model heads? I know i have to do something to the center bolts but what??

tpi_roc

You need to drill them at a different angle


Pre 87 heads had all bolts in at the same angle

Post 87 heads had the bolt holes in the center angled more "skyward", so you just need to angle those holes slightly different. Places like summitracing.com sell little tools to help you drill it out.

ERICCAMARO

I have access to a drill press that would probably do the trick right?? What do you mean by skyward do you mean more vertical?? like straight down anyways thanks for the help

91-ZZ4-Z28

Edelbrock makes a tool for this that makes it easy.

Manifold Bolt Hole Slotting Tool #8501

I is about $50 from summit but makes nice clean angles the Summit part# is EDL-8501

ZZsmpch

iTrader: (1)

You can spend $50 on the tool, or get a used manifold that works for $40 off of ebay like I did They seem to go pretty cheap.

ERICCAMARO

Good call. Think ill do that and save myself some work.

dacuma

hey check it out it I just did this, I got some photos of the drilled out intake, and the bolts and spacers you need, its in my album,
http://community.webshots.com/user/dacuma
its like the first two photos.

ERICCAMARO

Sweet where did you get the bolts and stuff.

dacuma

I got everything from summit, its the holley intake bolt kit, and edelbrock slotting tool, that is part number 8501, I did a post on the adaptors, its on here somewhere, I forgot that number, I ll find it and post it later.