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Discussion Starter · #1 ·
So I'm hoping someone can give me some advice here. I'm shopping around a cam and lifter kit for my 71 pontiac parisienne which has a 400 stock. Can anyone recommend a kit that is compatible with stock heads. I don't know what come with the stock engines, and I've never opened up this engine before. Is there anyway to upgrade to a little bit better cam and lifters without having to change the heads? i wouldn't mind getting a little more power.

here's a photo of her
 

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Depends on the heads it has. If you have number 99 heads then you have a decent compression ratio to work with. Something in the range of
216 intake 228 exhaust at .050 with like a 112 LSA on a 108 centerline
If you have the number 96 heads then you have a real low compression engine due to the head volume.In which case I would search for a better set of heads,and as allways replace the timing chain with a new one when doing the cam swap to ensure good performance.
For the engine with heads numbered 99, a summit 2801 would be a decent choice but will probably need a 2500 stall to get your lead sled moving well off the starting line
The 99 heads have 86 CC chambers , and that is sweet.
The 96 have 96 CC chambers and that is ...not so much
400 with 86 CC chambers = 8.7 to 1 static
400 with 96 Cc chambers = 8.0 to 1 static
Of course without tearing the heads off and actually CC ing them you wont know what you have .
If it were mine I would throw caution to the wind and put in a comp cams XE 262 regardless of the heads it has.
If youre going dissasemble the engine and do some checking then get busy and post back some more info ...:thumbup:
 

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Discussion Starter · #6 ·
okay first straight and informative answer ive got, so thanks for that. Two more questions. how exactly would you measure the cc of the heads? and if i put in a XE 262 and as you say, throw caution to the wind? whats the worst case scenario? the cam blows if its not compatible?
 

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Naw, the XE 262 should work well with either set of heads on your engine.
The XE grind has a fast closing rate on the aft side of the lobes which helps build compression and keep intake vacuum up for power brakes.
The dynamic compression suggests that you should be good to go on pump gas.
you may need 92 octane if you have the tighter #99 heads as dynamic CR will be at 7.3 ish to 1.
Be sure the cooling system is in good shape.
Also I am asuming You have a 4 barrel engine.
Did you check the head numbers also?
Please verify head numbers. Better cam choices may be out there.
Oh... CC ing the heads requires removal of said part. We can go there if you want.
 

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Lunati voodoo part number 10510702 would also be a good choice. IMHO.
 

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Sweet ride!

It's always a good idea to run the numbers from the engine and heads to see exactly what you are working with. Even knowing what the engine is, there's always a chance someone has rebuilt it- and that will often mean the compression is no longer stock.

Installing a mild cam like LATECH recommended is fine. If the engine has many miles on it, rebuilding the heads can help a lot. And while the heads are off the compression can be determined.

Headers or good exhaust manifolds will also help, along w/a free-flowing dual exhaust system. If it has a Q-jet, keep it and the intake. I'd recommend installing a HEI distributor.

Lower rear gears can really wake up the acceleration, just don't get too carried away. 3.73:1 might be a bit much, especially if you do a lot of HW driving. If that's the case, 3.42-ish ratio would work well. You should check to see what differential you have, 8.5" or 8.2". I don't know about the Parisienne but there were 8.5" 10-bolts used along about '71 in some GM full size cars, IIRC.
 

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What a beautiful barge. I dub thee 'Large Marge'

Seriously; if you want to swap the cam, you'll need new lifters and probably want new springs to go with. Id pull the heads and have them cleaned, inspected and CC'd (filling the combustion chamber with a measured amount alcohol to determine exactly how large the combustion chamber is for optimizing your cam choice). This will also give you a chance to see if the heads have been milled, if the surface of the block has been milled or if rebuilder pistons or performance pistons have been retrofitted. Milling the heads and/or "deck" of the block (the flat face the cylinder head mates against - with the proper head gasket) will raise the compression, usually for higher performance. However, a milled block with a small cc combustion chamber could necessitate higher octane fuel and retarding the timing more than normal.

You'll need new head gaskets at a minimum, and a helper to make it easier to remove the heads. If you go this route, don't order the cam/lifters and springs before everything has been verified
 

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Discussion Starter · #11 ·
Hahaha!! large marge!!!

I think that will be the road i will take. i'll find out what heads i'm running then make my decisions based on that. I am running a quad but its a POS...i need to get it rebuild, vaccum issues... current exhaust is the original manifold which need TO GO! i had a nice dual exhaust rebuilt around them for now, but ive been loking for headers to fit my frame for a while, i probably will need to have them fabicated. ive bought two sets of headers in the past and they didnt fit, frame in the way. Thanks for the advice and liking my ride! I named he Rosie the Impaler, but Large Marge may stick hahaha.
 

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We call those "darksiders". The big Pontiacs have a personality unlike any other big American car. Another term that "fits" is GALY (Great American Land Yacht).

Headers for the B-body are a crap-shoot at best. I would prefer the HO exhaust manifolds used on the '69 Firebird called "long branch". Ram Air Restorations makes them, marketed by the good Pontiac resto houses (Ames Performance, Performance Years). They make power like headers and last like iron. They're longer than your logs, so your new pipes will just have to be cut and "flared" to fit.

The XE grinds are our most popular, but the Dual Energy cams are very good in the big car, too. 275DEH is one we used in the 428 with excellent results. Good power and 17 MPG in a '69 Cat wagon.

FWIW

Jim
 
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