pontiac 389 build

[SCOTTGTO66]

I am rebuilding a 1966 pontiac 389. I have it torn down to the bare block and am getting ready to send it out and have it magna fluxed and bead blasted. It may get bore .10 over. This will be my first engine build and have access to all the tools as a friend of mine used to do this alot. I am looking for suggestions as to what I should do about a cam, pistons, lifters etc??? The car is a 66 gto conv. and I would like something that sounds and performs respectably. I will not be racing it but more cruise in's, ice cream trips with the kids etc (and an occasional burnout). I am trying to build on a budget (1000-1500 if possible). If you have any suggestions, please let me know. Thanks-Scott

[SStrokerAce]

The stock performance cam for the 345-370hp 400-455 cams was a hyd flat tappet 230/240 @ .050 .516 lift and 114 LSA.

Comp has that but they also have a 228/236 .520 lift 110 LSA cam that looks like a winner to me. Cam part number 51-309-4 Grind Number 276AH-10. Get some new lifters with it and new valvesprings to match.

Pistons can be anything from a Speed Pro rebuild kit to a Kieth Black Hypereutctic.

Bret

[Zee]

Welcome aboard Scott!

I'm not sure if you want to go .100 over as that will take you to a 4.160 bore size which would require custom pistons and ring selection may be limited. Not sure how safe the block would be at that overbore although a .030 455 carries a 4.180 bore. If you meant .010, same deal, custom pistons and rings are likely. No way any custom pistons are going to fit in your proposed budget. I take it your machinist will recommend .030 and go with speed pros.

Anyway cam choice is far more critical in a Pontiac than a Chevrolet due to the limited RPM range of the lower end. I would recommend reading Jim Hands book throughly before making a camshaft selection. That being said, my recommendation for what it sounds like you want to do is Crower's 60916 221/229 @ 112 LSA.

Also you can poke around the PY site and see cam choice has been beaten to death over there: http://216.178.81.108/forums/?

Here's a link to some of Jim's testing and writing. You will likely fid the camshaft and manifold sections most interesting: http://www.classicfirebird.com/hand/hand.html

You will quickly find out, most of these trails have been blazed before and what works and what doesn't is pretty well known. No need to reinvent the wheel. If you have a GTO, you already have most of the parts you need to go very fast if the proper cam is chosen.

[67bird]

Scott,
Get ahold of Ken's speed and Machine in FL or with CVMS. They can help you with any engine decisions you need to make. Also, check out the Pontiac zone forum. The guys that own the two shops listed are members there and are always helping people to make decisions. Another source is the new book that Jim Hand came out with on building performance Pontiacs ( previously listed above). Its a good read and I highly recommend it, and it's probably the best $20 you will spend before you build your motor.

[Zee]

This might help you on your budget if you move quick: http://216.178.81.108/forums/showthread.php?t=464123

[SStrokerAce]

Yall I didn't pick that cam out of the wind...

Tightening up the advertised duration from 308/320 to 276/284 means something.... that 308/320 cam was designed by Tom Neil, who was in my parents wedding. As much as Ponchos aren't my favorite, I'm kinda related to them.

That Crower cam looks good as well, I would just tighten up the LSA some.

Bret