71 L48 engine mods

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Aug 31, 2009 | 02:57 PM

fgunnr

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71 L48 engine mods

I have a '71 matching numbers coupe with the base 350/270 engine.

This is a sunny day driver and will never be a NCRS car as long as I own it.

What engine mods could I do that would not devalue the numbers matching engine.

I know about carb, headers, intake and such as long as I have the original parts that can go with the car. My concern is what happens with the addition of cams, pistons and such.

thanks

Aug 31, 2009 | 04:12 PM

Easy Mike

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From: Southbound

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You could rebuild to the 68-70 optional 350 hp version. It would look stock and most bystanders wouldn't know the difference.

Sep 2, 2009 | 07:29 AM

fgunnr

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Quote:

Originally Posted by Easy Mike

You could rebuild to the 68-70 optional 350 hp version. It would look stock and most bystanders wouldn't know the difference.

What would this include?

Sep 2, 2009 | 08:14 AM

Easy Mike

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From: Southbound

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Cam, valve covers, carburetor, possibly the intake. Any of the how to rebuild your small block Chevrolet reference books will have the specs for the 350/350 version.

Sep 2, 2009 | 07:42 PM

7T1vette

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From: Crossville TN

If your car is basically "stock", anything you do to it that departs from a stock assembly will cost you money when you sell it. The best money you can spend to improve engine performance is to rebuild the carb and distributor, recurve the distributor per Lars Grimsrud's papers, and keep it well maintained. {Just my .02.....}

Sep 2, 2009 | 08:00 PM

AllC34Me

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From: Easton, PA

St. Jude Donor '10

Quote:

Originally Posted by fgunnr

Bump for you. I am anxious to hear the answers to this one myself. I'll sit and listen. Thanks.
David

Sep 3, 2009 | 08:14 AM

Ganey

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From: CORVETTE 77 385 C.I. TEXAS

The hp gain for the 350hp is mainly cam, heads w/ larger valves & higher C/R.

When an engine is overhauled it is common to bore & replace pistons.
So you would use pistons that give a higher C/R.

68-72 standard hoods have limited clearance. One should consider the entire flow path.
The previous 2101 Performer & Chevy's bow tie intake are similar. Chevy has said it was as good as the high rise (LT-1). Chevy's bow tie logo & Edelbrock logo are behind the thermostat housing & not on the passenger side runner.

Cam- You should state trans.

Sep 3, 2009 | 03:02 PM

bobbarry

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From: Providence RI

I've got the same car and same engine, and the same dilemma.

At rebuild-time, I would recommend going to a 383 stroker kit, and porting the heads to complement a more modern-profile camshaft.

It would appear completely stock from the outside, but roughly double the hp of the stock engine.