I dont get it......

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Patch

Patch

Patch
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Oak Harbor, WA. 98277
I got my engine home....(1975 360) pulled the 2 barrel manifold off of it....and then the valve cover......somebody........stuck 318 heads on this 360......3769973 casting number......Why....why would someone do that?......My question is.......the heads are fresh apparently.....nice soft umbrella seals and all....but wont this absolutely kill the performance of the 360? the combustion chambers are 2 to 3 cc smaller......but the flow and valve size is smaller.......should I just run it as is until I can build up another set of heads......or will it even be worth it to run it with these heads on here?
Thanks in advance.......Pat

:angry7:
 
The heads are not going to totally kill things off. The smaller port volume will likly increase velocity of the intake charge, resulting in better atomization and cylinder fill. The valves are slightly smaller, but it is not going to completely kill the flow. Run them while you build or buy another set, and then you can go all out on your other heads, and drop them on for a big HP gain.
 
So even with the intake port mis-match.....my 1971 340 manifold I have for it will run fine? I am assuming it would.......just not what it "should" be.....Thanks......
 
So I have heard about the EQ? heads on Ebay....are those only magnum style? I have a set of 3769974 heads.....are these decent? They are the 1.88 intakes...so I am assuming i can punch them up to 2.02's......With the magnum style head.....do you have to run magnum specific intake manifolds?
I opologize in advance.....I know these questions have been asked before.....Pat
 
magnums suck, if you run magnums your just like the chevy lovin moderartors.
 
People do dump and unexplainable things. By way of example your reading my post. However, Mopar Action did a head flow shoot out in the last magazine. If your ditching your heads you should look at it. There is some cheap austrialian heads they seemed to like that I'd never heard of.
 
Patch said:
I got my engine home....(1975 360) pulled the 2 barrel manifold off of it....and then the valve cover......somebody........stuck 318 heads on this 360......3769973 casting number......Why....why would someone do that?......My question is.......the heads are fresh apparently.....nice soft umbrella seals and all....but wont this absolutely kill the performance of the 360? the combustion chambers are 2 to 3 cc smaller......but the flow and valve size is smaller.......should I just run it as is until I can build up another set of heads......or will it even be worth it to run it with these heads on here?
Thanks in advance.......Pat

:angry7:[/quoteThere are many odball mopars out there. I bought a 360 at a swap meet last year that came from a mid seventies motor home. The two barrel was for a 318, the intake matched the carb, there is no choke well on the intake, the choke is electric and on the carb. The heads are marked 360 have no visable casting numbers and have 318 ports and valves. The head gaskets were original mopar items. I also have a 318 that has International Harvester cast on the block in 4 places and none of the usual mopar markings. Just when you think you have seen it all, some one holds up a mirror.
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this set up will make more low end torque such as a 4x4 or tow rig can use.
 
Well that makes sense.......I did however find pioneer melt plugs on the head frost plugs......so at some point not too long ago they were put on......is there anyway to back track through pioneer to find out when???



daredevil said:
this set up will make more low end torque such as a 4x4 or tow rig can use.
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Like the guys said they will work decent and not totally kill the performance. Low end will be better but you'll loose some perf. at the top end. The 974 heads you have are ok castings. Better than what you have but I don't think their enough better that I'd go through rebuilding them to put on. More than likely you won't gain a bunch with them. Save your money for some good aftermarket heads like the EQ's or Eddy's. Even the small valve EQ's flow real good and will boost the compression some and like Mopekid said they have them with LA intake bolt angles. Only other thing you need to do with them is switch to magnum valve train components.
 
............The 318 heads will pick up the low and mid range quite a bit,top end wont b affected much on a low comp engine...they will raise comp approx 1 point [comp = hp] ur 360 heads will b very hard pressed 2 try and keep up.....kim.......
 
oldkimmer said:
............The 318 heads will pick up the low and mid range quite a bit,top end wont b affected much on a low comp engine...they will raise comp approx 1 point [comp = hp] ur 360 heads will b very hard pressed 2 try and keep up.....kim.......
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That's right. The 973 heads do have a smaller combustion chamber than the 360 heads so the compression increase will offset most any perf loss the bigger valve/port heads have.
 
That works for me guys.....I dont plan on tearing this thing apart.....I'm going to take a peak at the main-rod bearings to see what their like and if all is well.....(Might put a mild cam in in) put it back together and run it to get the car all set up for a small block.....previous leaning tower of power......:)
Thanks for all your help!
 
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