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Pontiac 400 Questions


stephenh
04-09-2007, 10:22 PM
This thread is open to discussion, but I am directing the questions toward Mr.Pbody.

Basics:

79 TA, 4-speed, 301, 308 rear end, A/C carCurrent status:

Car is in the body/paint shop in Kansas. Hope to have it finished by the end of May.
I have a 77 400 shortblock in my garage here in Iowa; .060 over, completely machined and balanced.
The 301 has a one-way ticket to the cold, dark corner of an unknown relative's garage......in a saltwater swamp.......acid rain.......and no engine stand.......jkWhile data mining the forum, I came across a very good piece of advice. "Make a plan and stick to it." Kiss that notion goodbye! I started out planning on a solid, streetable, and mostly affordable engine. Well now I've realized that I will be able to do a good deal of work to this engine. The guy at the machine shop talked me into getting cast aluminum pistons. He says they are strong enough, but I would hate to invest a great deal of money in this engine only to have a piston shatter. Hear is my plan as of now:


Edelbrock Performer heads
Edelbrock Performer intake(possibly RPM, I haven't checked into the shaker hood adapter kits yet)
Comp. Cam 224/230 @ .050 (very open to suggestion)
Hydraulic Flat tappet lifters
Decent push rods
Better-than-Stamped rockers
Holley 650-850????
Headman/Hooker/Doug's headersMy feeling is that this is a fairly standard build for good streetable power, but the parts lend themselves to alot of tinkering. I won't spend much time at the track, but I want to have the ability to give whiplash with a touch of the pedal. I think the pistons would be fine for these given "bolt-ons", as I will spend most of my time under 5800rpm. But what if.........

Questions:

72 or 86cc heads? My motor guy said 72cc heads would give 9.99:1 compression(given bore, stroke, head gasket thickness, and piston dish.) Is this a safe combination with no worries of detonation? 86cc would give 8.75:1, but would just be begging for the 461 stroker kit.
How can I use the cam to compliment this slightly high compression ratio.
Which ratio of rocker?
Opt for roller rockers now, or wait to redo the entire engine as a roller?
This may sound a little crazy, but should I sell my pistons on e-bay and fork over the cash for forged pistons now?
How far can I go with this engine before the stock 4-speed, drive shaft, and rear end are in danger?I will update with pictures sometime this week.

Thanks,

Steve

stephenh
04-10-2007, 08:40 AM
How do i get a picture on here?

maxwedge
04-10-2007, 08:43 AM
Interesting, I am in the process of this myself, not my car though. Check the build up and results in Oct. 2006 Hot Rod magazine. Also check the build at pontiac street performance.com ( no spaces). Eutectic pistons may be the way to go, remember this a mid range torque engine, 5500 rpm , The rear will be a problem with any bite. With aluninum heads 10:1 comp. is doable especially with an aggressive cam.

stephenh
04-10-2007, 09:37 AM
How aggressive of a cam would be suitable for 10:1 and still allow plenty of vaccume for all of my accessories as well as pleasant in-town driving? What is a good upgrade for my rear end that will allow 500hp? Is the tranny strong enough? What's a good clutch upgrade? The car will see plenty of highway driving, so I don't want racing gears. I understand the physics of engines, I just don't have the wisdom that years of engine building provides. Also do you know how to identify the cc volume on a set of Edelbrock heads? There is a used set on eBay which look decent, but the guy doesn't know the cc volume.

stephenh
04-10-2007, 12:50 PM
How about this setup:

Edelbrock 72cc heads ported by Rock n Roll Eng.
Crane full roller rockers
Comp Roller Cam, 236/242 @ .050 with hydraulic lifters
Edelbrock Performer/RPM intake
Holley of undecided sizeGetting close?

maxwedge
04-10-2007, 03:14 PM
They have to be checked for the cc's unless Edelbrock has a part number that tells the cc's. You would need an O/D trans to really have a cruiser with a true 5oo hp engine as I said get that issue of Hot Rod all your answers are there. Vacuum will be an issue with thtat cam you need a storage tank. With a regular 4 spd over 3.55 is tough to highway cruise unless you have a large tire on there.

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