I've had 3 pontiac engines 2 were 455's nearly the same as the 400. Use a dual plane manifold Mine was an edlebrock with a holley 750 vacume sencondaries for street but changed it out for a double pumper when i changed the cam to a Compcam 292 adv. with 501 lift quite choppy. The 280 compcam adv 280 with 480 was great for the street but both combinations needed a stall converter its was about 3000 for the bigger cam 2400 on the 280 both had headers and 4.10 rear end gears. You need to change out the valve springs.Pistons were 10 3/4 to 1. I used a cam kit summit. gl
301's are not good candidates for high performance. But if 210 - 220 HP, 4500 RPM. and 120 or so pounds lighter than a small block chevy are ok then this little indian orphan with finned aluminum valve covers might work.. With a 252, .425 lift cam, .025 off the deck or head gasket, attention to detail, extrude honed exhaust it will look something like this. The Qjet CFM is controlled by the air valve opening, it is easy to thread a hole at the stop and make it adjustable. We would run them from 2500 to 4500 in second and tune until we got the best result. There was a W72 option but it is not well documented. Here is a Sim:
Had a 1967 400 in my 65 bonneville and it hauled ass no problem Posted using the Full Custom H.A.M.B. App!
Crane makes the 068 "blueprint "S" cam...Put it in with a 4 degree advance key..All you need for this application..An Edelbrock Performer aluminum manifold will look nice on there but 67-72 Q jet and intake will run just as well.
So is a Pontiac 301 really that bad ? Not when it's a 400 pretending to be a 301. Some compression will really wake it up, then you can pick a great cam. http://www.wallaceracing.com/head1.htm Smaller chamber heads would be the easiest quickest way to that if the bottom end is good and doesn't need new pistons. But you'll need to know which 4x heads you have to start with to make it worth the effort.
All the 400 4bbl 4x heads have 98.2 cc. The 6x-4 heads have 93.7cc heads. A set of those milled .025 will put you close to 8.5. You would need to mill the 4x .050. 3 cam charts. Since the Crane 068 doesn't have seat to seat figures, I used the .050 plus 15 rule for DCR.
What do you want to do with it. Drive it or street race it. A good manifold and exhaust should be enough to wake that motor right up. An Early q-jet manifold works as well, if not better than many aftermarket manifolds. Same with the factory cams. Many aftermarket grinds use the same lobes designed for Chevy Engines. I'd go with the H.O. Cam
So, I am looking at a 19080 Trans Am turbo with the 4.9 Turbo here in Europe. The seller, a specialist in importing US cars states the engine runs quietly and the auto box shifts smoothly. But the turbo is blown so performance is down, he claims he has a new turbo boxed and ready to fit but he is too busy to do this. Now I smell a large rat, the turbo on this is easy to access I reckon I could change it myself without too much hassle and the seller is a garage with a workshop attached. What is he hiding? Why doesn't he fit the new turbo? (p.s. this will be my second Firebird, back in the day I had a 3.8 v6 in my twenties).
turbos don't "blow" and run quietly. Large rat present. best thing to do with a 301 is salvage the oil pan, front cover, distributor, starter, carb and throw everything else away. use the parts to dress out a 400.
Thanks, I'll pass on it, it just very suspicious that a well-equipped garage or shop skips doing a simple repair that would add thousands to the sale price citing the reason is that they are too busy. I belive there is more to it and the engine is trash.
I was working in a Pontiac store back then. Replaced many 301 for cracked block behind the starter. Plus all the cracked Fiero blocks. Seems like all we did was hd line work.
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