Opinions on 360 build

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ok now, with the heads i was thinking, the IMM/RHS ones, they only do head cc volumes of 62-67 cc's, that will give me far too much compression with the kb's correct? like closer to 10.8-1. i would like to run it closer to 9.5-1 if possible but with those heads and the kb 107's would i be able to tone it down that much just with head gaskets? i'm still learning guys lol. thanks again for the help!!
 
I don't have a comp. ratio calc in this thing/handy. But I think a really thick gasket is needed to get that ratio from the head/piston combo. I doubt it to be honest. Cometic makes custon gaskets, but at the thickness you'll need, it will create other sealing problems with the intake to head and intake to block.

This may not be the best way to go. You should look for other pistons to work with the cylinder head cc amount. Perhaps a advertised 9.0-1 piston or a replacement piston that sits higher in the cylinder than other pistons from different years.

At 10.8-1, your goping to need a blend of race fuel to go with the high octane pump gas with those iron heads.
 
ok thanks rumble, thats kinda what i was figuring, if i can get that set of pistons that i had mentioned in my original post i think that would be perfect. even a combo of pump/race fuel is not an option, this car will be driven pretty much every day during the summer on the streets.
 
Remember when running the KB hyper pistons, you MUST adhere to their ring end gap requirements. That means that you will need to file fit the rings. A lot of builders don't like the extra trouble. Speed Pro's hyper pistons don't require this. Failure to do this will result in the ring ends butting together when the piston heats up. That would suck. This is why some people don't like the KB pistons. They think they are a drop in piston and it's not quite true. They are great pieces, but they just require some special work to get them right.
 
The KB-232 is a step dish with 18cc volume, and would give around 9.5:1 compression with 62cc heads. More expensive than the 107s though...
 
I think you're on the right track with the build. If you can answer a question... Does your car have power brakes?
As far as pump gas and compression, static compression ratio has virtually no effect on ping or detonation by itself. It's misleading and drastically oversimplifies when that is used as a guide. There are 9:1 engines that will ping like mad on high-test because the parts are mismatched or something's done incorrectly. The combination of piston, chamber design, head material, and camshaft (most critical) are what affects the ability to run pump fuel. I have 10.8 engines running pump 87, and depending on the build static ratios can reach over 12:1 on pump 93 (with the 10% ethanol that's mixed in our gas now).
 
Ok, so it doesnt have to have any high vacuum signal.. So really you can do anything you want. Here's what I'd do: Use the KB107 flat tops. Set things up to have a quench of no more than .035", and pick a cam of decent size to avoid low speed cylinder pressure.
 
ok guys so a bit of an update, a couple of you have posted on my 318 thread as well and right now i'm just trying to figure out budget problems. i was thinking on doing up my 318 a little until i could really afford to do this 360 but its looking like what i was hoping to do with it would turn out to be more of a waste of money then anything so i'm looking around to see what i can do to this 360 for the least amount of money possible, i wanna do it right but only have so much money. What do you guys think of this??

http://www.summitracing.com/parts/FEM-CSMHP814-600/

the rebuild kit on that link there looked like a fair price for what you get but opinions please. has anyone used any of these kits? But as usual i'm having compression ratio problems, at the bottom there its says approx. comp. ratio with a 68 cc head is 8.66:1 which is lower then i need. now as mentioned before the heads i'm planning on using can have from a 62-67 cc chamber my question is though is that enough to make a decent comp. ratio between 9-1 or 9.5-1? Let me know what you guys think, i'm in the middle of the road right now with whether i should just do this 360 or not, and this being my first build i still have tons to learn. again thanks very much i appretiate the input!!
 
rumblefish360 said:
I don't have a comp. ratio calc in this thing/handy. But I think a really thick gasket is needed to get that ratio from the head/piston combo. I doubt it to be honest. Cometic makes custon gaskets, but at the thickness you'll need, it will create other sealing problems with the intake to head and intake to block.

This may not be the best way to go. You should look for other pistons to work with the cylinder head cc amount. Perhaps a advertised 9.0-1 piston or a replacement piston that sits higher in the cylinder than other pistons from different years.

At 10.8-1, your goping to need a blend of race fuel to go with the high octane pump gas with those iron heads.
Click to expand...


OP.... E-85 and keep the compression you desire (fuel system/ carb upgrade)
 
moper said:
I think you're on the right track with the build. If you can answer a question... Does your car have power brakes?
As far as pump gas and compression, static compression ratio has virtually no effect on ping or detonation by itself. It's misleading and drastically oversimplifies when that is used as a guide. There are 9:1 engines that will ping like mad on high-test because the parts are mismatched or something's done incorrectly. The combination of piston, chamber design, head material, and camshaft (most critical) are what affects the ability to run pump fuel. I have 10.8 engines running pump 87, and depending on the build static ratios can reach over 12:1 on pump 93 (with the 10% ethanol that's mixed in our gas now).
Click to expand...

That's interesting to note because my 318 pinged pretty bad at times and compression on that couldn't have been higher than 8.5:1 (stock 1970 pistons with #302 heads). However my quench height was pretty big, I'm guessing this is what messed things up. When I took the heads off some of the pistons had weird burn marks on them and were chipped all along the edges toward the intake/inner side of the block from the detonation.

Now when I build my 360 I'm going to set it up for tight quench and go all-out smoothing and rounding the edges in the chambers and piston faces. I really want to see if I can make 10.6:1 static comp and a mild cam (for the cubes and compression) work with pump gas. If I do it right this thing will be a torque MONSTER and 20+ MPG should be attainable.
 
thanks for the link speedotann, i've read through that before and it looks like its really good info. i guess right now i'm trying to find a set of pistons thats going to keep me at a decent comp. ratio for a decent price, any opinions on the kit i mentioned above??
 
It's true you can run a high static compression ratio on pump gas. No doubt about it. But doing so, the engine will never acheive the power it could cammed properly to run on race fuel. It will have to have a lot of overlap and duration at .050" to bleed off enough cylinder pressure using iron heads to run pump gas. Likewise, a lower static compression ratio engine can spark knock like a rattletrap with a camshaft that has too little overlap and a short duration at .050". It's all about the entire package.
 
rumblefish360 said:
StrokerScamp said:
YES! I have. YES! it is possible.




Neither





LOL, OMG, your useing a chiltons to argue your point, ROFLMAO!!!!!!!!!
Bwa ha ha ha ha ha ha




I did it everyday in my daily driver. 4 seasons long, 3 years running, everyday.
Also,, every high performance car these days run more compresion and hotter cams than what was listed here.



Back peddling allready? You started this "Battle"
Click to expand...

10:1 on today's pump gas? You betcha...even for us "layman".

Think: QUENCH.
Click to expand...
 
74scamp360 said:
thanks for the link speedotann, i've read through that before and it looks like its really good info. i guess right now i'm trying to find a set of pistons thats going to keep me at a decent comp. ratio for a decent price, any opinions on the kit i mentioned above??
Click to expand...

I am looking at the same thing but .030 or .040 and without the pistons. I am gonna buy the KB Hyper flat tops... mine is gonna be floating around 10:1.

.060 may be taking off to much meat which will give you thinner cyl walls.

Is that the coolest thing package #9 495hp non stroker, 10:1 stock rods and crank with "J" heads!! Whys spend 5-8 grand on a stroker that will only make a few more Ponies!!
 
rumblefish360 said:
I don't have a comp. ratio calc in this thing/handy. But I think a really thick gasket is needed to get that ratio from the head/piston combo. I doubt it to be honest. Cometic makes custon gaskets, but at the thickness you'll need, it will create other sealing problems with the intake to head and intake to block.

This may not be the best way to go. You should look for other pistons to work with the cylinder head cc amount. Perhaps a advertised 9.0-1 piston or a replacement piston that sits higher in the cylinder than other pistons from different years.

At 10.8-1, your goping to need a blend of race fuel to go with the high octane pump gas with those iron heads.
Click to expand...

Disagree on the Cometic thoughts. Just put .065 MLS gaskets on a small block...everything aligns and seals fine.
 
Speedotann said:
I am looking at the same thing but .030 or .040 and without the pistons. I am gonna buy the KB Hyper flat tops... mine is gonna be floating around 10:1.

.060 may be taking off to much meat which will give you thinner cyl walls.

Is that the coolest thing package #9 495hp non stroker, 10:1 stock rods and crank with "J" heads!! Whys spend 5-8 grand on a stroker that will only make a few more Ponies!!
Click to expand...

Whoa...settle down there stroker basher. Let's think for a minute, shall we?

Yea, pistons are a little more and I can't figure out for the life of me why KB doesn't have more Hyper choices for what is a very popular stroker. To recap the 360 vs. 408 costs...

Stock rods $175 - Scat I beams - $300
Stock Crank $200 - Cast 4.00 crank -$300
Balancing $100 - Stroker balance - $180
Pistons $350 - Stroker pistons - $480[/U] (Probe forged)
$825 $1260

*Re-doing a stock crank, rods and balance a 360 with new pistons are my local prices here in CA. The crank re-do does include a mag, straightness check, turn, polish and chamfer. Rods are tanked, both ends re-sized and new QUALITY bolts.

So, $435 more for 43 more inches and WAY more torque. We don't even have "$5-8K" in our 416 all forged race 416 that goes low 10's! By the way...it REALLY did cost $180 to balance it.

You better be REAL good with porting those J heads to get 495 REAL HP from a 10:1 360...ba wah....hahahahahaha
 
Wow, I'm as bad as the rest of you guys...

Didn't mean to stray from the OP post: Let's digress to the 360 suggestions he is asking for.
 
dusterdoug said:
Whoa...settle down there stroker basher. Let's think for a minute, shall we?

Yea, pistons are a little more and I can't figure out for the life of me why KB doesn't have more Hyper choices for what is a very popular stroker. To recap the 360 vs. 408 costs...

Stock rods $175 - Scat I beams - $300
Stock Crank $200 - Cast 4.00 crank -$300
Balancing $100 - Stroker balance - $180
Pistons $350 - Stroker pistons - $480[/U] (Probe forged)
$825 $1260

*Re-doing a stock crank, rods and balance a 360 with new pistons are my local prices here in CA. The crank re-do does include a mag, straightness check, turn, polish and chamfer. Rods are tanked, both ends re-sized and new QUALITY bolts.

So, $435 more for 43 more inches and WAY more torque. We don't even have "$5-8K" in our 416 all forged race 416 that goes low 10's! By the way...it REALLY did cost $180 to balance it.

You better be REAL good with porting those J heads to get 495 REAL HP from a 10:1 360...ba wah....hahahahahaha
Click to expand...

WoW, Didn't meen to upset you Doug.
 
Speedotann said:
Is that the coolest thing package #9 495hp non stroker, 10:1 stock rods and crank with "J" heads!! Whys spend 5-8 grand on a stroker that will only make a few more Ponies!!
Click to expand...

Take those figures with a grain of salt...
 
Here is my budget 360 build I used KB 107 pistons with the baddest street cam ever made.....LOL seriously I ******* love this cam crane powermax will work great with stock stamped rockers. Seriously the baddest street cam ever made Sounds a lil rougher than a stock 340 cam. I have 19 in of vacuum 114 lobe sep. My cylinder pressure is at 160 with a .040 head gasket Runs on 93 octane with 35 degrees total timing. Heads were cc at 69cc they were 72 before doing some cutting on them. 360 j heads with 2.02 valves in them.
Specs: .30 over 360
J heads bowl cleanup 2.02 valve
.10/.10 cast crank
Eagle I beam rods
KB 107 flattops
Crane Powermax cam
Intake Duration at 050 inch Lift222
Exhaust Duration at 050 inch Lift234
Valve Lift with Factory Rocker Arm Ratio0.467 int./0.494 exh.
Lobe Separation (degrees)114
LD 340 intake
Promax 750
1.6 roller rockers
3.91 gears
SS springs
Reverse mauual valve body
3200 converter

Car Runs 13.40 @ 105mph through the mufflers shifting at 5500
Attached Images
 
I do take the Numbers with a grain of salt. It is not like he is advertising a product though, so the #'s are probably close to truth. Those combos where also put through dyno tuning runs which helps a lot! I would be a little upset to here that a performance rebuild almost makes as much power as the common 408 stroker after I just spent the Dough to build the stroker!
The page is just showing you that you do not have to go buy a huge stroker kit and aftermarket heads to make decent to great power! Sorry if you do not accept this!
 
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