318 build

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Brandon689

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Hey guys I'm thinking about running kb399 pistons in my 318 I have 360 heads on it with stock 318 pistons but trying to get some more performance out of the 318 so I'm wondering if it would be a good combo with porting and polishing the 360 heads and some kb399. Any insight is appreciated I tried searching to see if there was any info on this combo but couldn't find anything
Setup I have now
318 stock bore with stock pistons and 360 heads cam I'm running is a lunati LUN-10200702LK and weiand action plus pro and quick fuel 750
 
Before we get started, use the search function for 318 builds. There are hundreds of threads about the subject. (and about as many opinions)
 
Welcome to FABO. The kb399 pistons might be a bit high in compression with the 702 cam. The kb 167 pistons will increase your compression a bit and work better with that cam. As far as the heads a good valve job and some bowl porting is all that's needed. Bigger valves never hurt.
 
JFLN said:
Welcome to FABO. The kb399 pistons might be a bit high in compression with the 702 cam. The kb 167 pistons will increase your compression a bit and work better with that cam. As far as the heads a good valve job and some bowl porting is all that's needed. Bigger valves never hurt.
Click to expand...

I’d take a second guess into actual fact of the matter since his “360” heads and what ever gasket he is making use of is an unknown.

W. See a little facts here as in how many cc’s the head has and what gasket is will be used. Then take a look here; KB Hyper Piston - Chry 318 Rod 6.123 Solid Dome -6cc 2V [KB399] - $444.93 : United Engine & Machine Co. Incorporated, Performance Pistons

From the link above, these are estimated ratios dependent on a few variables?
Trying to follow the numbers...
60cc-11.7, +4cc’s lower the ratio .7 to;

64cc-11.0, +4cc’s lowers the ratio .6 to;

68cc-10.4, +4cc’s to 72cc’s,lowers the ratio .6 or .7, IDK, this is a best guess from following the link numbers. But the math looks like;

10.4 - .6 = 9.8-1.
10.4 - .7 = 9.7-1

The missing variable, head gasket thickness. However, you can vary this to an easy 1/2 point or more in ratio. Down to 9.2-1?

Sit down and play with a ratio calculator and various head gasket thickness and then cal Cometic gaskets for there MLS gaskets. I had a set
Made up @ .100 thick.
 
Rumblefish360- What? No LMAO somewhere in your post. I think you missed a gear.

"W. See a little facts here as in how many cc’s the head has and what gasket is will be used." The op can use a thicker gasket to lower compression or a thinner gasket to raise compression. He can also cut the heads to raise the compression. He can leave the piston at .012 below deck to lower compression or 0 deck to raise compression. Once he has more info he can go from there. I should have given more info to the op so here goes-
With new pistons I figure 0 deck.
Felpro 1008 gaskets at 4.17x.039
Ported heads would be surfaced with a minimal cut so 70cc heads.

The kb399 piston would be 10:1 compression. The kb167 piston would be 8.9:1 compression. With the open chamber iron heads and lunati 702 cam which can use a stock torque converter I would use the kb167 pistons. Now when the op knows more he can change things to suite the build.
 
A pox on both their houses but not much choice
no quench with either
so 9:1 with that 262 lunati voodoo should get the intake down to .006 around 57 ABDC and stock gears and converter
the 10:1 should have a bigger cam and a hp converter (and gears)
do the heads like have been said seat and 60 degree about the same width 72 and a little 80 then blend and a top cut
me I'd run cut down 2.02 valves with a 30 degree seat where the existing top cut is now with that cam flame retardant on
carb? can you return it would be ok with 10:1 and much bigger cam and low gears but overkill going to take some tuning
simple AVS would be plenty
 
Wyrmrider said:
A pox on both their houses but not much choice
no quench with either
so 9:1 with that 262 lunati voodoo should get the intake down to .006 around 57 ABDC and stock gears and converter
the 10:1 should have a bigger cam and a hp converter (and gears)
do the heads like have been said seat and 60 degree about the same width 72 and a little 80 then blend and a top cut
me I'd run cut down 2.02 valves with a 30 degree seat where the existing top cut is now with that cam flame retardant on
carb? can you return it would be ok with 10:1 and much bigger cam and low gears but overkill going to take some tuning
simple AVS would be plenty
Click to expand...
??? You were using voice typing on your cell phone weren't you. LOL
 
I've been playing around with some option the one I think I may go with is kb167 and set of aluminum heads 58cc that cc includes the 5cc you lose from the valve reliefs in those piston I'll run a felpro head gasket 0.039 and according to the compression calculator should put me around 10.5 I'm going to get bare heads and have them set up at a machine shop as for needing a bigger cam I've debated maybe running 1.6 ratio rockers but not sure and I have a 2500 stall converter and 4.10 gears. I'm still young and learning so try to take it easy on me lol
 
toolmanmike said:
??? You were using voice typing on your cell phone weren't you. LOL
Click to expand...
Lol I was wondering wth he was talking about i read it like 5 times and still didnt get it. That makes sense now! I thought it was some secret car language us newbies havent learned about yet. :rofl::poke:
 
you may only need 1.6 on the intakes but iron rockers work fine up to .550
if roller tips then read and understand the 4 articles on the B3 website
there is no getting around relocating your shafts when you add the radius of the roller
 
Well if I do go with a different cam I wouldn't be sure as to what would be a good cam with the heads and piztons and not sure how much lift I would be able to get away with
 
Brandon689 said:
I've been playing around with some option the one I think I may go with is kb167 and set of aluminum heads 58cc that cc includes the 5cc you lose from the valve reliefs in those piston I'll run a felpro head gasket 0.039 and according to the compression calculator should put me around 10.5 I'm going to get bare heads and have them set up at a machine shop as for needing a bigger cam I've debated maybe running 1.6 ratio rockers but not sure and I have a 2500 stall converter and 4.10 gears. I'm still young and learning so try to take it easy on me lol
Click to expand...
If you mean the AL heads are Edelbrocks with 63 cc heads, then the 5 cc's would ADD to the chamber volume, not subtract from it. So you should use 68 cc's not 58 cc's, if I am guessing how you are working the numbers. (And congrats for doing that homework.)

KB167's end up around .012" below deck for a standard LA deck height. With that and the Edelbrocks and the 1008 head gasket at .039" thick, I get a static CR of 9.25. DCR with your cam is 7.6. Decent for a street engine with decent low RPM torque, and quite a step up for a 318. Nice that you will a chance at some quench effect now. With the 2500 stall and 4.10 gears, you will need a larger tire budget LOL

Put on the 360 heads with a typical chamber size of 72-73 cc's, unmilled, with the same KB167's and head gasket and the SCR drops to 8.3 and the DCR drops to 6.8.... DCR is about that of a stock low compression 318 so low RPM torque will be about the same.
 
nm9stheham said:
If you mean the AL heads are Edelbrocks with 63 cc heads, then the 5 cc's would ADD to the chamber volume, not subtract from it. So you should use 68 cc's not 58 cc's, if I am guessing how you are working the numbers. (And congrats for doing that homework.)

KB167's end up around .012" below deck for a standard LA deck height. With that and the Edelbrocks and the 1008 head gasket at .039" thick, I get a static CR of 9.25. DCR with your cam is 7.6. Decent for a street engine with decent low RPM torque, and quite a step up for a 318. Nice that you will a chance at some quench effect now. With the 2500 stall and 4.10 gears, you will need a larger tire budget LOL

Put on the 360 heads with a typical chamber size of 72-73 cc's, unmilled, with the same KB167's and head gasket and the SCR drops to 8.3 and the DCR drops to 6.8.... DCR is about that of a stock low compression 318 so low RPM torque will be about the same.
Click to expand...
Would you suggest running a different cam with running aluminum heads and kb167 and thanks that's my bad I thought you subtracted
 
Brandon689 said:
Would you suggest running a different cam with running aluminum heads and kb167 and thanks that's my bad I thought you subtracted
Click to expand...
Does the cam fit the need?
A larger cam duration wise moves the rpm band up.
Does that fit the build better?
 
9.low x:1 compression .028 gasket
262 Lunati voodoo the shorter seat than the 268 comp should bump you DCA- maybe nm will run the numbers (or the similar duration Howard with the "15 footnote)
either gives you more lift so no need for expensive rockers and the B3 kit and you can use your current gears and converter
more duration then the 10:1 motor and spend lots of money to get the whole combination- and no real difference around town
 
rumblefish360 said:
Does the cam fit the need?
A larger cam duration wise moves the rpm band up.
Does that fit the build better?
Click to expand...
Yes, that is the question that the OP can help to answer. Is this mostly for street/cruise use, pure drag racing, rally/road race, or hauling logs? The cam selection will changed with that, and the emphasis on compression ratio may change a bit, and CR should track cam selection to a fair degree.

If 'twer me, I'd mill the block deck roughly .012" to get the pistons flush to the deck, OR just use the Mr Gasket 1121G head gaskets to get the piston-to-head gap down to a range that is good for quench effect. Once there, then there is a bit more flexibility for cam selection; i.e., you can go shorter if desired and stay away from detonation, especially with those AL heads. And, it bumps up SCR and DCR about 0.2 points.
 
A change in ratio isn’t needed for a small cam size change. Example; Next cam size up. Head gasket thickness can do most if not all the changing required. Unless your already at the thinnest gasket now.
 
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