V4motorsports

I have a stock 71 350/270. It needs a new cam, so after I pulled the intake, I found it full of something:


and the inside:


The water passages are almost completely clogged, oil wasn't changed on a regular basis, etc.

So…..

I am going to pull the engine and rebuild over the winter. I want to keep the stock auto transmission and stock 3:08 gears. It will be used mostly for a daily driver and cruises, no racing (have another car for that). But I do want to pump it up a little.

What are anyones recommendations?

Thanks

Russ

bluedawg

Well we got the intended use, but what we need is budget and power goals, plus what you have done to her already and how much originality you want to maintain.

oops!

V4motorsports

Thanks Dawg,

Its an all matching number car, so I'd like to keep it looking stock.

Thinking maybe 350/400 hp but still very street able. I know I will lose a lot of hp by keeping the original intake and exhaust manifolds, maybe stock heads but with a good valve job, different cam.

Just looking for some ideas. Again, doesn't need to be a monster. Would like to be able to turn the key and go.

Haven't done anything to it besides already pulling the intake and heads.

Thanks

Russ

bluedawg

While it's not impossible to reach That power level it will take some work and money. I'll suggest moth balling the original, buying a four bolt truck block and building either a 350" or a 383". You would need everything set up right to achieve 350 to 400 horse. For starters I'm suggesting headers, but check napa's Web site along with several others summit, jegs etc. Looking for 2.5" rams horns, I'm not as familiar with your 71 but it may have them already. Next step would be the heads, here I'll suggest aluminum and you can paint them to match, but if your set on steel, you can look for a set of cast iron vortecs from either Straub Technologies or scroggin dickey performance, the crappy part about vortecs is you can't use your stock intake. So if the intake has to be stock, maybe the route to go would be send you intake and heads out to a porter like scott foxwell or Eric wiengarter and have them ported as a set, be sure to explain your plans and ask about a camshaft to meet your goals, remember that the camshaft needs to be matched to the gears and converter if auto, so if the camshaft gets large enough you'll need to change gears etc. Start researching and let's hear what you come up with.

oops!

Revi

If you want 350/400hp (gross) you will need to get your compression in the low 10's:1 range, get better flowing heads(bigger valves) and a better flowing intake manifold or more cubic inches (383).

My very original, but "massaged" 70 L-46 makes 341hp/387tq.(engine dyno), an LT-1 intake manifold might add another 15hp. After that you will either need to make a 383 out of it or use non-GM intake manifold and heads.

V4motorsports

Dawg,

GREAT info! Thanks, thats what I was looking for.

Revi,

Now thats what I'm talking about! How/what did you do to massage everything?

Russ

68post

I'd want a mild 383 roller cammed engine under all of the original equipment for a nice "stock" look. Should drive very nice with 3.08's and an auto !

A lot of different avenues to go down and still have a stock look.

63mako

Retro roller cam, Bump compression to about 9.5 to 1, 383 internally balanced Scat rotating assembly, 2 1/2" Ramhorns and mandrel bent 2 1/2" pipes with free flowing mufflers, Maximize quench and pocket port, cleanup heads with 3 angle valve job. easy 350 - 400 HP, totally stock look, matching numbers, won't break the bank. The stuff you see in the engine is very typical in a 40+ year old engine. If your 400 trans is stock you already have a 2000 stall convertor.

Revi

The block is .030 over (not decked), pocket ported original heads, 3-angle valve job, 10.4:1cr, gasket matched. The only non OEM part was the cam, Comp Cam xe262h-10. Has a nice lumpy sound to it. I wish I had the time and funds to also dyno test the original cam (3896962) to see if one performed better over the other.

The cast iron intake manifold doesn't flow well above 5600rpm. One of the sacrifices in keeping it original.

V4motorsports

Revi,

since I don't plan on running it up to 6500 rpm's, do you think the 2 bolt mains will be adequate?

Like you said, LT 1 intake would help it breath and still look stock.

Thanks everyone for all the ideas.

Russ

BKbroiler

Two bolt mains are all you need. I have 200 runs on my 2 bolt 383 with no problems.

Mike Ward

Won't look stock at all. You'll need to change the carb, air cleaner ***'y and the hood.

You need to balance how much internal work you want to do with how much your want it to look stock.

garygnu

how much do you want to spend ?how much will your wife let you spend ? you can find good 383 ,short and long blocks for a good price .check out competition products for sbc 383 .