kb167 pistons good choice for 318?

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69-318

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Iv got my 318 torn down and was thinking of going with the kb 167 pistons and zero decking to get some compression. are there any negative thoughts towards this? the 318 is a magnum but i was gonna loose the roller lifters and go with hyd.flat tappet and bigger cam and just rework the stock heads.
 
Your goiong to need to calc your ratio with a zero deck height and the cylinder head cc to see where it is at.

IMO, it would be silly to loose the roller cam.
 
i would love to keep the roller cam if i could. the only reason i was gonna replace it is because its in bad shape and unfortunatly im on a tight budget with this build. i need to get new pistons anyway so i was wondering if the kb 167's would be my best bet.
 
I think most people agree the KB's are good pistons. I agree on trying to keep the roller. If your lifters are good you could probably reuse them. Maybe somebody here has a deal on a used roller cam?
 
Well, I think it'll be a 9.9 to a 10.1 ratio with a standard fel-pro .039 gasket. To high for pump gas in your area? And the intended cam for the engine?

If your lifters are good, then it's just the price of a cam.

Otherwise, by the time you converter over, it'll be more money rather than staying with the roller. Your choice.
 
i was wanting to go with something just over .500 lift and around 230 duration at 0.050 lift. our premium gas is 91 octane here. i had a bent pushrod that might have been caused by a gummed up lifter or something else? i know the lifters can be rebuilt. like i said id love to stick with the roller cam if i can.
 
Well, you'll need more cam or less compresion cause the 91 will probably not feed it right.
 
what about comp cams 20-247-4? its 236 duration at 050 and .528 lift with 1.6 rockers?
 
Have the heads been checked for cracks yet? You could help decrease to a safer c/r with those pistons by running a .049 head gasket, and bore over .020 if necessary. That's a c/r of 9.35:1 w/ stock bore or 9.44:1 w/ .020 over bore. Your cam choice will also lower your dynamic c/r. Also consider your altitude into the factor. Higher being more resistant to detonation due to lower cranking compression. Why not buy a single replacement lifter?
 
69-318 said:
Iv got my 318 torn down and was thinking of going with the kb 167 pistons and zero decking to get some compression. are there any negative thoughts towards this? the 318 is a magnum but i was gonna loose the roller lifters and go with hyd.flat tappet and bigger cam and just rework the stock heads.
Click to expand...

Those are nice with 1.81 compression height and all but they are expensive. I found some Mopar 9:1 pistons that I think were put out of production on a website that is called 1stchryslerparts.com they are cast pistons with the old late sixties forged compression height and are MUCH cheaper than the Keith Blacks; about 130 bucks for all eight plus shipping. Part number is: P4529419. The hypereutectics are better for durability but not if you are on a budget. It would take a bit more milling to zero deck the cast ones, but I wouldn't jump on decking until you measure what the deck height is with pistons with a dial indicator and figure your compression ratio with the combustion chamber cc and head gasket thickness first because you might go too high by zero decking it and you can't put the metal back on.
 
im going to clean and inspect the lifters in the next few days and if its just the one thats damaged ill replace it and stay with the roller cam. i checked 1stchryslerparts.com but couldnt find those pistons. would there be a better choice in pistons than the KBs? i was reading about a few builds with these and zero decking making around 400hp. is this unrealistic? im going to have the heads rebuilt with bigger valves. my altitude is 3740 feet but id like to drive to the coast at some point. my idea was to safely lift the super low compression ratio as high as i can to reach my hp goal. if possible.
 
have the heads checked for cracks. i started to work on mine and found cracks in both heads between the intake and exhaust seats..2 or 8 and 1 or 7.... you said mag motor so im assuming mag heads... 10 bolt valve cover

my 318 in my ramcharger is TBI its roller but non mag.... 5 bolt valve cover
then its a cam lifter and pushrod swap
 
Losin the roller would be a fool thing to do. Those lifters are the more expensive of the two and you already have those. They can be reused over and over and rarely go bad. The roller will be head and shoulders above what any flat tappet can do. That engine was designed around a roller cam. Changing that will likely result in failure. ...and no, 400 HP is a very realistic goal.
 
69-318 said:
im going to clean and inspect the lifters in the next few days and if its just the one thats damaged ill replace it and stay with the roller cam. i checked 1stchryslerparts.com but couldnt find those pistons. would there be a better choice in pistons than the KBs? i was reading about a few builds with these and zero decking making around 400hp. is this unrealistic? im going to have the heads rebuilt with bigger valves. my altitude is 3740 feet but id like to drive to the coast at some point. my idea was to safely lift the super low compression ratio as high as i can to reach my hp goal. if possible.
Click to expand...

I just went on there and plugged in the parts number and it came right up. P4529419 You have to put the P on there too. On high octane pump gas which is 93 I think the highest ratio you want is 9:1 or so. There's other things that come into play though such as the duration on the cam where the intake valve stays open longer after bottom dead center which effectively lowers the dynamic compression ratio and you can actually get away with running a higher static ratio like 10:1 or so. I suppose high altitude would change that somewhat don't really know what to tell ya on that though.
 
thats odd i just checked 1stchryslerparts.com and again it didnt show any results for p4529419? are they available anywhere else? yes im deffinatly gonna try to stick with the roller cam. i havent had the heads checked yet but i heard they are notorious for cracking between the valves. hopefully mine will be ok i want to keep this build on the cheap. yes it is a magnum motor from a 96 truck i believe? if i find the lifters are in good shape then ill start shopping for a cam and pistons.
 
well heres an update i dissassembled, cleaned and reassembled all of my roller lifters and they all seem to be as good as new so now i gotta start shopping for a roller cam. about 3/4 of the lifters were seized with gunk and the plungers wouldnt move at all but thankfully now theyre all working fine. i guess the old owner didnt like to change his oil.
 
Nah, it's a magnum thing................ just like they had no low end torque at all. (But the 95 318 put out more HP than the 454)
 
69-318 said:
thats odd i just checked 1stchryslerparts.com and again it didnt show any results for p4529419? are they available anywhere else? yes im deffinatly gonna try to stick with the roller cam. i havent had the heads checked yet but i heard they are notorious for cracking between the valves. hopefully mine will be ok i want to keep this build on the cheap. yes it is a magnum motor from a 96 truck i believe? if i find the lifters are in good shape then ill start shopping for a cam and pistons.
Click to expand...

That's strange you can't find those sure it's the right website? Here is the screen right here.

PIST&PIN-318 ENG 9.0 C.R. [Part# P4529419]
Quantity:

Chrysler
Price:$24.00
List Price:$24.00
Your Price:$16.80
PIST&PIN-318 ENG 9.0 C.R. [Part# P4529419]
Quantity:

Jeep
Price:$24.00
List Price:$24.00
Your Price:$16.80
PIST&PIN-318 ENG 9.0 C.R. [Part# P4529419]
Quantity:

Dodge
Price:$24.00
List Price:$24.00
Your Price:$16.80

I just copied and pasted that, 16.80 a piece!
 
ok stupid me, i found those pistons. i was using the keyword search on the home page wich wasnt turning up anything. i think im going to have to bore the cylinders so im not sure if ill be able to use them. one of the cylinders has some small scratches from a damaged piston. so unfortunatly i might have to go with the KBs. friday im going to bring the block and heads to the machine shop to see what in dealing with and then ill know for sure.
 
69-318 said:
ok stupid me, i found those pistons. i was using the keyword search on the home page wich wasnt turning up anything. i think im going to have to bore the cylinders so im not sure if ill be able to use them. one of the cylinders has some small scratches from a damaged piston. so unfortunatly i might have to go with the KBs. friday im going to bring the block and heads to the machine shop to see what in dealing with and then ill know for sure.
Click to expand...

You already have the KBs? Well I'd use those then if thats the case. Those ones I mentioned are .030 over from the factory.
 
rick360 said:
You already have the KBs? Well I'd use those then if thats the case. Those ones I mentioned are .030 over from the factory.
Click to expand...

no i dont have the KBs yet i didnt know those were .030 over. tomorrow ill bring my block to the machine shop and see what he has to say. i measured my cylinders so i know it hasnt been bored yet. where can i find specs on these pistons i cant find much info on that site. ill buy the ones from 1stchrysler parts if they will work. if they wont work how are the speedpro pistons? they seem to be reasonably priced. keep in mind that i was hoping to get this 318 close to 400 hp. im not going to beat the snot out of this thing all of the time but i definately will once in a while.
 
ok so heres an update i got my block hot tanked and magnafluxed and theres no cracks and theres minimal wear on cylinder walls so a .030 overbore will clean everything up nicely. i think i am going to go with the Keith Black hypers from speedway. so now my next question is which rebuild kit should i go with? the guy at the machine shop and i were talking about Federal Moguls complete kit. (minus the speed pro pistons) but id like to get some opinions from you guys first before i start ordering parts.
 
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