look, I'm told by my grandfether that there's pretty much nothing i can do to get more power out of it. Apparently, block is too weak to bore it, stroke is too long to make it a stroker. Any ideas? I want to beat his 89 that has a 351W bored and stroked, so its pushing around 440 horsepower. I want be sure he's telling me the truth or if he's just scared of getting his *** kicked at the strip.

 

What kind of meds is your Grandfather on?? A stock displacement 390 (with the proper equipment) will kill a Windsor....stroker or not.

However, you need to start saving for some 428 CJ or 427 low riser heads. Those crappy truck heads are the first thing that needs to go.

 

wow, thats news to me...ill have to go tell that to my 390. you can stroke it out with a kit for about 1900.00 and get massive power. the 427s wont clear the 4.05 bore too easy. go with some edelbrocks or the blue thunder heads. slam on a good intake and a nice cam. drop in a 428 crank and you have a merc 410. they came stock with 440ft lbs. so imagine a 445 stroker...some of the older 360/390 blocks can be bored out to the 428 bore. that 80 over...thats a lot of boring...so no, they didnt have thin walls...

 

I don't know the exact numbers on my basically stock 390 rebuild, but its enough to peg the speedo in 2nd in my 73' in under 15 seconds (3rd is broken, just got the Trans Manual today)...with my old engine in the back.
Here is what I did;
I ported the Exhaust on the stock heads (D2TE AA) heavily, almost to the point where the bump on the inside of the runner is gone. I then lightly ground and polished the chambers to to eliminate as many hot spots as possible. I also did some light porting and polishing on the intake side but only to match up to the intake manifold. I'm running a stock 'T' or truck 4V intake mated to a Holley 2bbl carb. I also ditched the stock exhaust for headers (35$ on craigslist) and a pair of Cherry Bomb Turbo Mufflers. I did a cam swap as well, which came from Ebay from a company called Maddog Racing under they're RV torque cam application. Here's the specs.

Lift 484/510
Adv Duration 270/282
Duration @ .050" 204/216
Lobe Centerline 112 (107/117)

The lift isn't that impressive, but I've been told by several people that with stock springs the max amount of lift you can run safely is .521 so i thought i'd keep it under that.

So far I'm really happy with the results and it gets better mileage than my old 360 that i had. I did this the cheapest possible way since the 360 decided to start eating the nylon timing chain about the same time my then G/F (Now wife) told me she was pregnant. Keep looking for those heads, but be wary and learn your casting numbers. I had some guy try to sell me some 428 SCJ heads that turned out to be 360 heads. Needless to say i was P*SSED.

In closing, keep looking for deals on craigslist because they are out there and try and learn as much about your motor as possible. PM me if you want to I'd love to help.

 

Try this out I got some good results from reading it.

390 Build-Up the Old Way Page 1