# Needing input on a 400 build



## Pontiaclover85 (Aug 23, 2020)

Hey guys, I recently purchased a 73 400 that was running but had low oil pressure ( had debris clogging oil passages by the oil tally plug behind freeze plug) engine is a two bolt 73 Catalina motor and has never been bored. I got two different approaches in mind but need some input. First approach- zero deck the block, stock crank, speed pro forged coated 4vr, cam that came with engine kit is an Elgin E-979-P with 420 intake valve lift and 443 exhaust valve lift and with 204 intak and 214 exhaust duration at .50, I plan on running a 800 cfm Buick quadrajet off a 71 Electra 455 with a 1 inch spacer under it, an hei distributor and I have a set of 7h1 heads off a Lemans I would like to mill and get close has I can to 9.1 -9.5 range for n my compression ( stock 4x4 heads seem like they need to be milked more and they too have press in studs and normal size valves instead of the large valves) ..... approach 2- basically same everything except with a eagle 4.250 stroke crank and either lc941 flattop pistons or lc938 10.6 cc dish pistons ( kit comes with either you choose. The car it’s going on is a 79 bonneville with a th350 and a 2.41 posi, car has ac and power everything and will likely never see high rpm driving do to its gearing. This car will simply be a highway cruiser that has plenty of power to pass anything on the highway and get decent mpg for what it is. This will be my first engine build So with my Gauls in mind and the car in mind what approach would be best for my needs ? I know Pontiac’s built for torque over horsepower so what type of torque could I expect from each approach? 
and lastly ( until I have another question later) will either or both produce good enough vacuum for the brakes and ac and cruise?


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## Pontiaclover85 (Aug 23, 2020)

Nobody......


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## PontiacJim (Dec 29, 2012)

Pontiaclover85 said:


> Nobody......


Cubic inches is what you want. Butler 461 stroker kit. Get Ross pistons to work with whatever heads you choose as long as you know the combustion chamber volume CC's. You can deck the block, and use a Felpro .041" head gasket to get you a .040" quench. Have the front oil galley plugs tapped for pipe plugs, but make sure they are not inserted too deep and cut off oil supply to the lifters.

Pay attention to the fit on your heads to manifold and valley pan when decking the block. You may have to trim the valley pan a little, as I understand, and you may need to mill the intake side of the head if you make a cut to the head surface. If the intake bolts don't fit easily, then the intake/head ports are off.

Use the *Best* brand rope/graphite rear main seal as it seems to work better than other options. Get a Butler Pro-60 PSI oil pump and aftermarket hardened oil pump shaft to match. 

Select a cam with a 114 LSA, and something around a 280 duration. Stock iron heads don't flow much over .460" lift unless you work them and watch for coil bind and clearances. Get a good 3-angle valve job. Stock dual plane intake with the Q-jet.

If you use the stock exhaust manifolds, I would clean/polish them up a bit and use as large a pipe I can with good free flowing mufflers.


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## pontrc (Mar 18, 2020)

PontiacJim said:


> Cubic inches is what you want. Butler 461 stroker kit. Get Ross pistons to work with whatever heads you choose as long as you know the combustion chamber volume CC's. You can deck the block, and use a Felpro .041" head gasket to get you a .040" quench. Have the front oil galley plugs tapped for pipe plugs, but make sure they are not inserted too deep and cut off oil supply to the lifters.
> 
> Pay attention to the fit on your heads to manifold and valley pan when decking the block. You may have to trim the valley pan a little, as I understand, and you may need to mill the intake side of the head if you make a cut to the head surface. If the intake bolts don't fit easily, then the intake/head ports are off.
> 
> ...


Drop the mic


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