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Discussion Starter #1
My brother is in the process of restoring his '69 GTO and we wanted to get thoughts on this engine combination. Car is an original 69 400 CI, 350 HP manual transmission car (based on the WT stamping on the block). His plan is to turn it into a Judge with functioning Ram Air, with some added HP. Below is what our plan is, any help or constructive feedback is appreciated. Thanks

Original 400 block, +.030 bore
Original crankshaft, turned .020
Clevite P-Series Full groove main bearings
Aftermarket 5140 steel I beam rods
Melling std oil pump
Speed Pro L2262F-30 pistons
Speed Pro Moly rings
Rotating assembly balanced
Original 48 heads reconditioned, milled .010, with Manley SS valves
Lunati 10510704 camshaft & lifter kit
Lunati springs, locks retainers
Comp cams push rods with new screw in studs and guide plates
Edelbrock Performer-Link True Roller Timing Chain Set
Comp Cams roller tip 1.52 rocker arms
Performer RPM intake
Holley HP 750 cfm carb
HEI ignition
New Harmonic dampener
All hardware and fasteners are new
 

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Discussion Starter #3
It's in the car and fits nicely under the factory hood (the carb spacer was just for the picture)
 

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jsj372: "Clevite P-Series Full groove main bearings"

PJ: Bad choice in my book. I have never run fully grooved bearings, but have run the 3/4 groove for this reason - You don't want a fully grooved bearing in the main cap (lower bearing). If anything, the best way would be to have gone with the 3/4 grooved main bearings. This gives a little extra oiling and still has the solid base section to support the crank which is where all your rotating force will be. This is a neat trick if you are racing and plan on tearing down the engine to inspect the bearings on a regular basis.

I would add the later oil pan with baffle to curb oil starvation on hard acceleration. Make sure you replace the factory oil pump rod with an aftermarket hardened piece.

Looking at your choice in pistons and milling the heads, I assume you are building a street/strip engine and will be running an octane booster or using racing gas?

My opinion here: Not a fan of the cam you selected only because it has a 110 LSA. This may further aggravate your already high compression ratio by providing a high Dynamic compression ratio. I did a real quick, not exacting, check and I get a Dynamic Compression ratio of around 8.9 to 1. Again, it won't be pump gas friendly - so be aware of detonation problems that may arise. I would have gone with 112-114 LSA. Prefer the 110 LSA cams on lower compression - under 9.0 because they do build more cylinder (Dynamic) compression. Also assume you ported the heads to improve flow for the higher lift and matched them to the larger ports on the intake. Cam overlap shows to be 60 degrees so manifold vacuum should be pretty good.

As stated, the Performer RPM intake may cause problems with hood clearance if running the RA set-up - it is almost 1" taller and am not sure if the Holley will add to this as well. I believe BearGFR may have pulled this one off and modified his set-up to work with the lesser hood clearances - it is one of his posts.

It may all work with a 2500 stall converter if automatic and some 3.90 gearing.

Just my opinion, not saying it won't work. Should be interesting. :thumbsup:
 
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