383 Stroker v. Pontiac 400 Stroker?

[Inspector71]

My neighbor is a union autoworker with GM. I like him but don't care for his attitude that because someone drives a foreign car (my wife does) they are not an American. Anyway my question has to do with a little friendly competition. He has a 67 Pontiac GTO and it is a very nice car. He had the 400 stroked and he said it now specs out at 461 cubic inches. I am working on a 68 Charger. For various reasons I want to stay with the 383 but have it stroked. 440Source offers a 438 and a 496 cube version. I want my car as streetable as possible (had over heating problems with past cars) and plan on going with the 438 build. That gives him 23 cubes over my '383.' However, as I was looking over his motor before it went back in, it appeared the Pontiac heads (iron) were kind of small compared to the stock 383 heads I am NOT using (I am going with Edlebrock aluminum heads). I am not anyone has ever confused with being an authority on this subject, but it seems to me that even if the Pontiac is stroked and big, am I right that the stock Pontiac head will restrict or hinder the performance of this engine compared to what I plan (I'll be using an aluminum intake, radiator, carb. and adding headers)? If so, will my 383/438 stroker stand a chance against the Pontiac 400/461 stroker? Thanks in advance.

[c00nhunterjoe]

The total cubic inches of the engine is only half the battle. The bottom end is nothing more then an air compressor. If your heads can't move the air in and out of then it doesn't matter how big your engine is.

Without knowing exactly what is done to his engine you can't really say whose car is faster. You can make a 383, 438 or 496 very streetable. It all depends on what combination you put together.

[Cooter]

496 C.I. from a 383 will require some SERIOUS rod to piston ratios...ALOT of stroke. Just because all that sh*t rotates on the stand, doesn't mean it's gonna make power @6000 RPM....


All this bench racing is wonderful, but it all comes down to weight of cars, drivers,engine power bands, traction, etc.
Just simply comparing dyno sheets is one thing, but I've seen alot less power run around alot more power on the street.

[Inspector71]

Thanks for the responses. It should go without saying that various factors play a role in how well and fast a car will run, something I learned years ago as a young man. It would seem that anyone on this forum already understands this. Bench racing is simply a point from which to begin considering what is possible and what is worth the work and expense. For example, I suggested that heads would play a significant role but wanted to test this idea by asking the more informed. I appreciate the responses suggesting that indeed, the 383/438 with really good heads will run better than the Pontiac 400/461 with small stock Pontiac heads.

[hatersaurusrex]

Maybe you shouldn't be trying to compete with someone who is an obvious knucklehead that would talk trash about what your wife drives.   Sounds like he needs a couple of knucks to the mouth to me.

[Challenger340]

Bench racing is best left at the Bench.....too many variables with Tire/gearing/suspensions/yada/yada

But in simple ENGINE terms....
Nuthin wrong with the Poncho's, they are capable of some decent power curves....and without knowing more about the particular combo used to achieve the 461 inchs...some characteristics common to all Poncho's will still be present, even with aftermarket heads.
that said, IMO,
far better internal Engine Dynamics present in the Mopar 438/383, in terms of Rod Ratio Balance to Heads, Oversquare Dimensions, Oiling, Bearing speeds/widths, etc., etc.
If we were Bench-Dyno racing....
I'd CLOBBER YOU with the Mopar from a engineering perspective, NO CONTEST !

I dunno about perspectives in Streetability, but pretty much childsplay these days to kick 525-550 Hp with 550 Ft/lbs Torque out of a 438 using out of the Box Eddy or Stealth Heads, and a Flat Tappet Hydraulic Cam on pump gas.
Please....
Don't try that at home with your Poncho...sad seeing grown men cry ??