What would you do?

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Scampin

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I'm in the planning stages of building a street/strip motor for the 64 barracuda. I picked up what I thought was a clean 360, ended up being a turd. Crank has already been cut .020, already been bored .020 and it looks like it may take another 20 to 30 to clean up.
I also have a 4" mopar crank, and a set of h-beam rods out of another motor that is going bigger. These are for a 340 block, which I have. I have a set of j-heads that just got freshened up, a few different intakes, and probably will end up with a thermoquad on it. The only issue I see, is I more than likely will end up using the 273 exhaust manifolds. I got a set of magnum manifolds from a member, but there is no way they will fit without serious modifications. So how bad do you think 273 manifolds will hurt a stroker? Will later 340 manifolds fit? I have a set of 72's.
What would you do?
 
Build the 416 out of the 340 and buy a good set of headers. You won't be sorry.

I personally would never run exhaust manifolds on a stroker. That's a lot of air to force through 273 manifolds.

I guess it all depends what the budget is and what your objective is. Sounds like headers would be your best bet.
Good luck.

-Mike
 
Think about it this way. A stroker is built to make more power because of the extra air it can move/ displace. You're gonna build that engine to move all that air & then try to blow it through restrictive exhaust manifolds designed for an engine 143 cu in less. I'd go nothing but headers on a stroker motor or anything "street/ strip".
 
Nothing like throwing money out the window by choking your stroker down to a power level worth crap by the use of exhaust manifolds. Look into tti for headers. I do not know if they have it for your year car. Or headman/hooker headers.

The exhaust manifolds is like throwing away a 100HP.
 
The early A v8 manifolds are the worst. Worse than the big block ones IMO and those are pretty bad... So if you wnt manifolds I'd just build the 273. If you are thinking bigger the 340 HP manifolds from teh 68-71s will fit and flow much better. Not sure about teh 72s but I think the only difference is the size of the outlets - on the 72 they are 2" rather than 2 1/4".
 
Unless your not planing on spinning it above 3000rpm headers are in your future.
 
I am looking to run 13.0's in any type of heat. The car is a 4spd with 3.23 gears and polyglass tires, I will have to drive 100miles to the track... I figure it will take around 330hp. The way I look at it is if I build the 360 I have to pay for a set of pistons, a crank, and machine work. Then the build has to be efficent enough to make .91 hp per cubic inch, which means I may have to push the compression up some.
If I build the 340 stoker, I have to pay more for the pistons, machine work would be the same, but I already own the rods and crank. Then I only have to worry about making .79hp per cubic inch. Which means I could probably get away with running piss gas.
Nothing is set in stone, just rolling ideas through my head.
 
Sounds like the following combo will suit you:
-340 w/ 4" crank
-new pistons to run with the stroker, probably about 9-9.5:1 CR max with iron heads.
-Aluminum intake, high(er)-rise/dual-plane, optimally an air-gap.
-Probably around a 750-800CFM carb, depending on the cam/heads. If you're going to drive it on the street, I'd avoid the double-pumpers.
-Clean up the J-heads and install larger valves if they're not already in there.
-Dougs/TTI headers, unless you want to scrape.

When you start looking at cams, make sure you match the cam to the motor and what you're trying to do. Call Comp Cams or Hughes and get a good idea of what kind of lift/duration you need to drive 100 miles to the track, race, and then drive home.

The 3.23s are going to hold you off the line, so don't get too wild with the cam. You will need some serious torque, but the stroker motor should help with that.

You should be able to hit your goal, but the wrong combination of parts could easily hold you back.

Good luck!
 
Scampin said:
I'm in the planning stages of building a street/strip motor for the 64 barracuda. I picked up what I thought was a clean 360, ended up being a turd. Crank has already been cut .020, already been bored .020 and it looks like it may take another 20 to 30 to clean up.
I also have a 4" mopar crank, and a set of h-beam rods out of another motor that is going bigger. These are for a 340 block, which I have. I have a set of j-heads that just got freshened up, a few different intakes, and probably will end up with a thermoquad on it. The only issue I see, is I more than likely will end up using the 273 exhaust manifolds. I got a set of magnum manifolds from a member, but there is no way they will fit without serious modifications. So how bad do you think 273 manifolds will hurt a stroker? Will later 340 manifolds fit? I have a set of 72's.
What would you do?
Click to expand...

So you have a 4 inch crank for 340 mains, does not fit in the 360. I would sell it to get some money for the rebuild of the 360 you already have. You can use the h beams, but i would sell them , too. If the 360 crank is ok then i would use it, bore the block after sonic Test is ok, most can take .060 inch overbore. Cast or hyper pistons will do the job if you dont plan power adders.

This should get you a fresh shortblock you can depend on without spending a lot of money. Buy a cheap set of headers, around 130 bucks at summit. Put it together and have fun!

Michael
 
Oh, i just noticed you have a 340 block, too......then i´d use the 4" crank of course - and sell the 360.

Michael
 
You can make that power through manifolds but you'l be losing a bunch from them. You'll also want a custom cam from someone that knows how to make power with bad manifolds.
 
Yeah the cam will be coming from Dwayne Porter. Though I know all about the losing of hp through manifolds, it may be too much to ask throwing the 273 manifolds on. What about making a set of log manifolds, something you would expect on a turbo set-up? I have done it on a turbo 4cylinder, pretty easy to do really. I'm sure someone makes the flanges....
 
I think everyone who has or had cheap headers in a A-body hate(d) them.
They hang too low and get beat up, etc... High dollar headers aren't much better.
I dont know how much mod work would be needed to get the magnum manifolds in there but it might be worth the effort. ( Switched left for right and upside down fits. Lets call that joke of the day. I dont know if it would fit or not. )
I think your left manifold has a near 90 degree turn before the dump that really restricts flow.
Good luck with whatever you decide.
 
My advice is to build a solid short block w zero deck pistons that can be upgraded with better cam, heads, manifolds later when you want to go faster. And believe me you will want to go faster eventually. And yes use headers.
 
Scampin said:
Yeah the cam will be coming from Dwayne Porter. Though I know all about the losing of hp through manifolds, it may be too much to ask throwing the 273 manifolds on. What about making a set of log manifolds, something you would expect on a turbo set-up? I have done it on a turbo 4cylinder, pretty easy to do really. I'm sure someone makes the flanges....
Click to expand...

Dwayne's definately up on making power with manifolds and his cams flat out work (not to mention his valve jobs/head work). But - you can use the later A manifolds and that would be my 2nd choice... Just get the best you can get (68-71 340 monifolds) because one way or another you will be pumping through them, not getting any help from them. I don't think making longs is wortht eh effort when a factory set will work.
 
Absolutely NO WAY would I put manifolds on a ANY performance oriented build unless it was due to a race class restriction. For example: Take a deep breath through your mouth, insert a coffee stir straw into your mouth, and now try to exhale....a bit of an exaggeration, but this is similar to what you are doing to a stroker engine with tiny exhaust manifolds. The better the engine can breath (move air/fuel), the more power you can make.

Get some good headers (not cheap-o's) and you will have plenty of ground clearance. Can you see my headers hanging down.....nope, they are just a tick higher than my low profile pan. I had some cheap-o black jack headers YEARS ago...flattened them when I hit a decent size dip in the road...never again.
 

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No way I would run any style stock manifold on a performance engine. I dont even like them on a stock engine.
 
Argh... The "other" motor is just going to eat up too much money this spring for me to build the stroker. I think I am going to be stuck with the 273, which ran fine, just leaked oil like a stuck pig. I am probably going to throw a 4bl manifold, and a cam in it. Possibly clean the heads up some.
Cam, and manifold suggestions? Have any ideas? I am sure it has been discussed 1000times.
 
IMO. Before I throw a cam in it, I'd simply save the money and just throw a 4bbl. On it and call it a day.
 
is it a 64 273? That uses the oddball intake bolt pattern. If it were me I'd swap on some 66 or 67 273 heads and run a normal LA318 intake on it. It's a solid cam so I think I'd keep it stock or get a custom grind made for it.
 
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