Toss the 318...too slow...

[Tripp]

Gentlemen - please clarify - the 66 Coronet 500 with poly 318 is just plain
slow - my question is: how easy is it to put a 383 or 440 in - do I need
a different transmission (its an automatic) - do I need a different raditator -
any front end suspension changes? Little surprises? - or is it just different motor mounts? Will the current power steering just bolt right on?
What headers do you suggest with the power steering? Is it a better
idea to bolt in a 340/360 crate engine? Note: I am not at all interested in
a 500+ HP monster -it will not be raced.

[Ray Bell]

You are better off just giving the Poly a chance to breathe...

If you do change, you will need to change the tranny, or at least the housing. Probably the radiator, and it really boils down to the fact that you'd be best off either sticking to the Poly and doing some work on it or buying a power unit complete out of a big block car and swinging the lot over.

The Poly has a lot of untapped potential, I believe. Stroked it has even more, but just giving it a chance to pump air will do a lot.

[custom880]

I agree with ray. The poly is unappreciated but a few people out there have found that they can be quite good engines. If you can get a 4 bbl intake, have some head work done slip a cam in you get one heck of an engine.

[dwc43]

Keep the original engine in it. You'll be bringing it's value way down by swapping in a non original engine too. Clones are not worth what an original car is worth and you'll be saving a piece of automotive history. Not many of these old cars still around you know.

[nhdriver]

Poly's are old tech & very hard to find H.P. parts for.To put a B engine in you need a Big block trans.& mounts The rad. should work. you will need some different kick down linckage. Another alternative would be a 360. You could keep your trans. (you would need to have your torque convertor rebalanced or you can use a B&M flex plate made for a 360) 360'S are cheap & readily available. There are lots of H.P. parts available for them too.

[Dick]

A four barrel carb will raise it from 230 HP to 260 HP. Dual exhaust will also help. That same motor was rated at 290 HP with factory dual quads in the Plymouth Fury a few years before. You might find a factory manifold (4 bbl) cheap.

Valve adjustments, points, plugs and condensor were all ingredients of a 318 Poly tune up. They run forever and are considered by some to be one of the best engines ever built by Chrysler.

[dwc43]

Poly performance parts are everywhere. Pistons are available. Comp Cams has the valve train and cams. What else you need. Headers are no big deal either. A 4bbl is just a 4bbl so that's not a problem either. Plenty of Thermoquads to go around.

[cutting torch]

My vote is to build the poly!

torch

[pishta]

I say go with the poly power too. Spitfire (Laysons) can make you a set of headers if he is still making them. Weiand still stocks a 4bbl poly intake. The trans bolt pattern is the same as the LA motor so if a crate 360 is in the works, you need not get another trans but you may eant to beef up your internals. Motor mounts should not be a problem with either LA or B, as the 66 probably came with a B as an option. The 340 timing set is an interchange, as well as the oil pump drive shaft, The poly already has a forged crank (same dimensions as a 318/340, with a small mod) a 360 crank can be used for a stoker as well as any of the other popular crank kits. Ah, give it a chance. You dont see a canted valve Mopar every day!

Hey, when did my age start showing in my posts? Not that it bothers me, but damn Dick, your old!

[Dick]

Originally Posted by pishta

Hey, when did my age start showing in my posts? Not that it bothers me, but damn Dick, your old!

Just like a Poly.............an oldie but a goody.

[dave571]

Originally Posted by Tripp

Gentlemen - please clarify - the 66 Coronet 500 with poly 318 is just plain
slow - my question is: how easy is it to put a 383 or 440 in - do I need
a different transmission (its an automatic) - do I need a different raditator -
any front end suspension changes? Little surprises? - or is it just different motor mounts? Will the current power steering just bolt right on?
What headers do you suggest with the power steering? Is it a better
idea to bolt in a 340/360 crate engine? Note: I am not at all interested in
a 500+ HP monster -it will not be raced.

Well Tripp, I'm going to agree with you 100%

Pull the 318 and keep it under your workbench if you like. It can't be proven original anyway. The blocks weren't vin stamped until 68. It can only be date coded correct that early.

If you do some check of values, you will find BB clone cars are worth more than original 318 cars in almost all cases, so don't feel bad about the pull.

For a BB....
Shumacker creative services sells the mounts although you can get a used set of mounts and brackets. No K frame swap is necessary.
http://www.engine-swaps.com/

Yes you need a BB 727.
You could probably find a water pump housing that would alow you to use the oem rad, but it will run hot. A rad from a bigger car (ie newyorker etc) will fit in there and keep it cool.
The suspension is the same. You could put bigger torsion bars in, but it won't change much.
Most regular off the shelf headers will work with powersteering.
You may need to modify the poly brackets, or find some old style BB brackets to make the old style ps work. Newer style stuff will be easier to find, but finding a hose to fit may be a problem. Easiest fix would likely be modifying the existing pump and bracket to fit.

For a crate LA SB....

No trans change necessary.
I don't know if poly motor mounts will fit a LA engine. Even some LA engines vary from others so you may need a mod there.
The ps pump bracket will still need modifiying to go onto a newer motor.
You'll probably need a bigger rad also.


To keep the poly....

Yes the parts are out there.
You can stroke and over bore the motor to around 400 inches. All it takes is money

It's your car man. Don't be afraid to make whatever mods you want. Those are cool, and don't look out of place with a BB or LA motor in them.

[Ray Bell]

Originally posted by pishta
.....Weiand still stocks a 4bbl poly intake.....

I haven't seen you posting for a while, my young friend...

Maybe you've been away? Anyway, while you were away, Weiand ran out of stock. No more. Second hand market only, but they are out there.

As are some original Chrysler ones... they're on eBay from time to time, some wreckers are bound to have something.

...or just wait until I get my manifold out of the planning stages and into production.

[pishta]

Originally Posted by Ray Bell

I haven't seen you posting for a while, my young friend...

Maybe you've been away? Anyway, while you were away, Weiand ran out of stock. No more. Second hand market only, but they are out there.

Oops, PAW still shows a part number, maybe some parts house still has a few. I see dual quads on Ebay all the time for the poly. Get creative and graft a P7 intake onto those heads!

[Sandman1]

QUOTE=pishta]I say go with the poly power too. Spitfire (Laysons) can make you a set of headers if he is still making them. Weiand still stocks a 4bbl poly intake. The trans bolt pattern is the same as the LA motor so if a crate 360 is in the works, you need not get another trans but you may eant to beef up your internals. Motor mounts should not be a problem with either LA or B, as the 66 probably came with a B as an option. The 340 timing set is an interchange, as well as the oil pump drive shaft, The poly already has a forged crank (same dimensions as a 318/340, with a small mod) a 360 crank can be used for a stoker as well as any of the other popular crank kits. Ah, give it a chance. You dont see a canted valve Mopar every day!

Hey, when did my age start showing in my posts? Not that it bothers me, but damn Dick, your old![/QUOTE]

Stay with the poly. TTI now has headers for your ride. Polys were cast 'fat' so most will easily take a .0.90 overbore (sonic test block first) that will give you 360 (JE Pistons). If you want more: http://www.ramracing.com/ has stroker kits available.

[Ray Bell]

Definitely sonic test first!

We've checked five blocks, several won't go the .090", none will without boring offset. That's not an issue with a road engine, but we're looking at a race engine and don't want to do that.

Worst case was an engine with .110" wall thickness on the thrust side, .235" on the other.

But Gary Pavlovich, who does a lot of these, says just that... you can bore them to .090", but sonic test first.

[REDNECKMOBILE]

Go with the B block conversion, you'll have all the power you'll need plus a smooth and reliable ride. The poly is too limited by parts and all small blocks are weak compared to a 440 with 350 horses unless you stroke which means big money.

[Ray Bell]

I fail to see the logic in that...

When you're faced with all the costs of a conversion... the little things that see the money run away, like the engine mounts, the radiator, the brackets, the new tranny, the exhaust system and so on, putting a bit of effort into the nice old Poly sounds much more enticing.

A low-cost stroker can be had by grinding a 360 crank's mains, after all, and using the converter from the 360. But then, a new cast stroker crank is $300 or so, and that gives 400 cubes anyway. With matching pistons, of course. But pistons seem to be on the agenda anyway, for both compression increase and as another means of grabbing capacity.

The only area in which the over-the-counter availability seems to be lacking is with the inlet manifold. This is one reason why I'm becoming more confident of the success I'll have with the one I expect to put on the market within the next year.

But all the same, they are on eBay, and at swap meets.

For more informed discussion on Polys, go to this site and join in discussion.

[dave571]

Originally Posted by Ray Bell

I fail to see the logic in that...

When you're faced with all the costs of a conversion... the little things that see the money run away, like the engine mounts, the radiator, the brackets, the new tranny, the exhaust system and so on, putting a bit of effort into the nice old Poly sounds much more enticing.

.

I fail to see the logic in that. The stuff to convert it is not expensive, and most of the stuff, is parts you would change when upgrading the old 318.

A set of used BB mounts/brakets for a 66 up B body can't be worth more than 40 bucks at a swap meet (if that much) they are not exotic.
You'll want a rad upgrade with ANY performance build that makes power.
Gonna run the old y pipe and single system on the performance poly?
727's are pretty cheap too.

You can't tell me that the parts to build a poly into a bigger motor, won't be more than the cost of picking up a BB 727, and some drive shaft mods, when you are changing the rest anyway.

It's a big car, a big inch motor will respond better. my .02

[dwc43]

It will all cost about the same either way, but keeping it original will make it worth much more in the long run.

[rumblefish360]

I'd keep the 318 close. Worth is like beauty, in the beholders eye. Performance wise, the big block can't be beat.
I echo what Dave571 said.

[usdart]

Where did all the Guys go that preach 'there is no replacement for displacement'?

If you want original then keep the 318, if you want HP then out with it!

[rumblefish360]

Hey, he could stroke it since it'll take a "LA" crank! Think overbore to 4 inch with 4 inch stroke. Muwhahaha. Why, Yes!, it's only a poly 318.

[Crank]

Originally Posted by dwc43

It will all cost about the same either way, but keeping it original will make it worth much more in the long run.

I don't see how it would hert the value i would rather have a big block than a poly penut in that heavy b body for one,plus he will allway's be looking for more power and will never be happy .IF this is going to be a daily driver maybe a polly is the answer but if not i would go big as i could even a 451 would be a nice swop .440's and 400's are not hard to find and allot of parts to choose from.So my vote is big block .