REbuild advice on parts

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photorep

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Hi..I am rebuilding a 360 for my '74 Scamp. The machine shop will prepare the block and heads(bore, align, hone, zero deck, balance) and I will be doing the actual build. So far I have decided on KB107 pistons and Comp cam XE268H and performer RPM intake.

My question is should i purchase a re ring kit from Summitt or Jegs or buy each of the components separately? Also, what piston rings, oil pump etc.
You guys get the idea...advice on the proper parts for a good street build. Hoping for about 375+ HP. Also, who do you think has best prices?
THANKS
 
Another question...The heads that came with my block arejust standard 360 heads with 1.88" (i think) intake valves. When the heads are reworked, should I enlarge the intakes too 2.02". Would this give my more HP or a better running engine?
 
What's your static compression going to end up being? It could possibly be high for pump gas with that small cam.
 
photorep said:
Another question...The heads that came with my block arejust standard 360 heads with 1.88" (i think) intake valves. When the heads are reworked, should I enlarge the intakes too 2.02". Would this give my more HP or a better running engine?
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You could probably make your 375 HP a reality with the 2.02s but at a pretty high RPM. You'll likely not turn such on the street so it's really money wasted, IMO. I would stick with the 1.88s.
 
I don't really know. I thought that KB107 with zero deck would yield about 9.5. Is that what you mean by "static". I am mostly a newcomer to all this so am not well versed in the important details.
I picked the cam by recommendations on this forum.
 
Yeah. That could be too high with iron heads and that mild cam. I would choose a cam with a little later intake closing event. JMO. What type premium fuel is available in your area?

Nothing wrong with the cam. It's a good one. If you zero deck that thing, you're gonna be askin for trouble on pump gas I believe.
 
Would the 2.02 decrease performance on street driving...or just not do anything worth the extra money spent
 
photorep said:
Would the 2.02 decrease performance on street driving...or just not do anything worth the extra money spent
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I thought I already answered that? Put the 2.02s in it. They will be there for bench racing and nothing else.
 
Johnny Dart said:
There is a couple engine builders on the site making really impressive numbers.
MRL Performance is one,and the other is Bryan at IMM engines.
Look them up,and see if you can pick their brain on the latest greatest combos.
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EXCELLENT suggestion. However, remember those guys have access to some very good pump gas or race fuel. The need to know your octane limitations. 91 is pretty lame.
 
I've also been told specifically 91 octane in SoCal is lackluster...a very good friend of mine had his Mustang tuned by Mike Murrillo in San Antonio for 91 octane gas; ran great there and in Abilene...ran 12.40s all day long N/A 306. As soon as he PCSd to SoCal, he had nothing but problems and detonation, couldn't even run it at the strip there without blending it 50/50 or more with Sunoco or VP 94.
 
Since it seems that zero decking the KB 107's might not be good with CA gas, what are my alternatives?
 
Are you dead set on the KB 107s? You know you can get a dish piston to drop your static CR to a more pump gas friendly number and still make your goal power.
 
photorep said:
Any recommendations gaskets , bearings, etc.....
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Felpro, clevite.

The CR doesn't worry me so long as you run a reasonable curve.

I'd be hard pressed to believe that bigger vlaves and resulting porting wouldn't help at all
 
photorep said:
Since it seems that zero decking the KB 107's might not be good with CA gas, what are my alternatives?
Click to expand...

Sit down with a GOOD online compression calculator. I like the one on the KB (United Engine and Machine) web sit. If you don't know all of your specs, FIND them out. Enter them in the calculator and see what you come up with. Start with the blueprinted spec for deck height (9.6) and see what comes up. Use the KB 107 as a base line. You can look the specs up right there on the KB site. IMO, if you are over 9.3:1, you will have trouble on pump gas with iron heads, unless you run a cam with an exaggeratedly late intake valve closing point....in other words a pretty radical cam. I would try to plan it all out like I have described above first. You can do all that without ever spending a penny.

Most of these people who tout high compression on pump gas with iron heads have never tried it and are parroting what they've read here or in car magazines. The truth is very easy to get to. All you have to do is look back at history. If compression was much more over 9:1, there was a sticker somewhere on the car that said PREMIUM GAS REQUIRED. And that was back when premium gas was 100 octane. Super Premium was 110. A TRUE, blueprinted 9.5:1 engine will struggle to run on any of today's pump gas without a cam that's really "too large" for a street car, or a limited timing curve, or both. That is WITHOUT quench.

Go read IQ52's low compression 440 thread. Look at the numbers he got from a 440 UNDER 8:1 compression. I think he proves that for the most part on the street, high compression is for bench racing. It's all in the heads.
 
I agree with everything except comparing a 8:1 440 to a 360. Having owned, driven and raced both in street trim. A 440 is a torque monster and a low compression 360 needs gears. LOL
 
I tend to agree with Rob, you need to plan out your build with limiting factors in mind. If your pump premium available is 91, then you definitely need to reign in your CR to a reasonable level...9:1 is a reasonable number. 9:1 is also a pretty good CR for cam flexibility and power potential. Proper planning, selection of parts, and execution of build will yield a good running engine with a wide powerband, streetable manners, and livable consumption (depending on the amount of lead in your right foot).

Check out this build from MRL:

http://www.forabodiesonly.com/mopar/showthread.php?t=216449

Meets your goal, has a great torque curve, pretty simple build-no exotic anything. If nothing else, it'll be a good guide to choose parts. YRMV
 
Having been there and done that with a 360, KB-107's as J heads with 2.02's.....

For you, I would first tend to the block, overbore only as much as needed. Then move to the crank and rods. I'd do new rods which work out cheaper and stronger than redoing the stock units. Then get your pistons and have the machinist assemble the shortblock and see exactly where the piston sits in the hole first!

The KB-107's are a 9.8-1 ratio with a 72cc chambers head and a .039 head gasket.

With these numbers, you can make slight changes to the final ratio. First is a thinner or thicker gasket. Fel-Pro makes a .055 thick head gasket. This is a minor drop, but .016 differance is a good start.

Your pistons may even be .010 down in the hole. See where it all sits first!

The cylinder heads chamber can be smoothed out and a coating to resist detonation an be used on top of the piston and head chamber. This can be cheaply done and before balancing it.
 
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