318 Poly Motor Upgrade

[Ron H]

Realizing this is a big question, please pardon me. I'm looking to rebuild my solid 318 in my '63 Fury over the winter to add some horses. I'm not thinking wild but in the area of 350-375 HP. I've put this off for years as my motor has remained real solid and rather peppy since I added duals, 4bbl, sure-grip, gears, among a few other minor upgrades. My issue is all of the info I've collected about possible options are mind boggling. If anyone has done such a rebuild I'd appreciate any advice on nifty upgrades. I'm looking at the basics with block/head boiling, cylinder honing, new rings, valves, seats, springs, cam, new rockers, etc. Any ideas?
Thanks!

 

[rumblefish360]

New rockers are available for the poly?
Do turn me on to the vendor!

The best thing about the poly is that it uses many LA parts so if your so in minded to stroke it,
390 cubes is an E-Z-2 do thing.

I'd also suggest a set of TTI headers and there full exhaust system @ 2-1/2 inches.

Cams can be had from racer brown or crane cams.

 

[Ron H]

Thanks Rumblefish360...well ok tossed out some broad engine components whether applicable or not...not sure about all components available for the poly; but tell ya got one helluva long list of possible upgrade parts from various well known vendors. As I've researched, the days of the 318 being better used as a boat anchor are long gone, especially for the poly motor (semi-hemi). I had been looking early on to drop it for a crate 360 or finding a 340/360 around but sort of like the idea of staying to the "factory" correct motor given its potential. Not looking to obtain a wild engine as this motor has the potential to garner, ya know 400 or 450+ hp. Going that far I think a 360 or b-block is better route. I guess reviewing the list I'll have to pick, choose, and delete to drum up a poly in the healthy 350-375 hp range. I had my right manifold reconfigured by a long time forum member (his source) and that's on the car now with a new 2.25 inch exhaust system, my old system was 2-inch. Low restriction...sounds meaner than hell; a loud bark with a mini bite right now. Headers for this car are priced in the sky (I checked TTI) and a heady install so went the reconfigured manifold route at least for now.

 

[threewood]

I had mine done by Gary Pavlovich and am happy with the results. Nothing extraordinary but it is a strong motor. Cam will make a huge difference but to get the power a set of headers is a must. Plus a 3 angle valve job and some port work to get them to flow.

 

[Ron H]

threewood, what do you reckon your HP is or around? Just out of curiosity if you've done this check post rebuild or know this, what's the compression? I have one weak cylinder #2 pumping about 100 and others are around 120-125. my motor still runs strong, uses no oil...go figure. Fact the motor has run so well I've kept putting off the rebuild but getting antsy to have more get up and go (to include the 727 rebuild as well). thanks.

 

[threewood]

threewood, what do you reckon your HP is or around? Just out of curiosity if you've done this check post rebuild or know this, what's the compression? I have one weak cylinder #2 pumping about 100 and others are around 120-125. my motor still runs strong, uses no oil...go figure. Fact the motor has run so well I've kept putting off the rebuild but getting antsy to have more get up and go (to include the 727 rebuild as well). thanks.

Horsepower estimate is a slippery slope. I would think with my mods it would be in the 340 range but that is just a guess as i have no 1/4 mile times or dyno runs. My compression is 9.5 to 1. You can get above that but it involves custom pistons which adds quite a bit of cost. My block was decked and heads milled to ensure straightness which helped the compression numbers a bit. I didn't go stroker for the sole reason I wanted to keep it reliable.

I was the same way, I wanted to keep mine as stock as possible. But then I wanted more power so the 2bbl had to go, then I needed headers to get full benefit, larger cam, head work, etc. I rebuilt the pushbutton 727, added a higher stall TC and governor that shifts at 5800.

 

[polywideblock]

check this out http://chryslerpower.com/webstore/Poly