piston out of deck????'s

Posted By: rice2muscle

piston out of deck????'s - 01/06/11 01:23 AM

i am planning on a stroker build, and the build will put the pistons 0.020 out of the hole. is this going to be a problem, with the head and gasket i will have enough piston to valve clearance so thats not an issue. it will have a mild 11 to one comp... one machine shop says it will blows the gasket out all the time and i should not do this... another says some engines from the factory do it all day with out an issue. so who do i believe?

ill level with y'all it is a 4 cyl honda engine. so there is ample head bolts to keep it snug. this is my rice.

Posted By: Twin Turbo Mower

Re: piston out of deck????'s - 01/06/11 01:25 AM

As long as you have proper piston to head clearence I do not see a problem.

Posted By: rice2muscle

Re: piston out of deck????'s - 01/06/11 01:27 AM

not going to blow head gaskets like the first machine shop says??

Posted By: MR_P_BODY

Re: piston out of deck????'s - 01/06/11 01:29 AM

You need to check the piston to head clearance... I
had a engine that was .030 out and at 8000 the piston
would JUST touch in one small area so I ground that
area on the head on a freshen up

Posted By: Performance Only

Re: piston out of deck????'s - 01/06/11 01:35 AM

there's different ways to look at it. they do make head saver shims for that so you can maintain the proper piston placement. if it's a stock rebuild daily driver deal, that's a good option. if your doing other mods as well, then that's a whole different scenario.

Posted By: rice2muscle

Re: piston out of deck????'s - 01/06/11 01:51 AM

thanks guys. i know this is moparts not hoparts lol, but on the honda forums 99.999% of all guys ask questions like how do i change my oil and what type of blinker fluid do i use??? so i dont really trust their opinion on engine builds.

Posted By: rice2muscle

Re: piston out of deck????'s - 01/06/11 02:08 AM

another quick question, not tyring to start a debate war here just wondering... will i make more power if i were to just get more compression? or if i were to stroke it but have lower compression?

Posted By: HotRodDave

Re: piston out of deck????'s - 01/06/11 02:11 AM

If you are running a closed chamber head you could get a cometic gasket .055 thick and get a nice tight quench area, even fel pro sells a head gaset that thick in there kits for small blocks at least.

Posted By: MR_P_BODY

Re: piston out of deck????'s - 01/06/11 02:14 AM

Quote:

another quick question, not tyring to start a debate war here just wondering... will i make more power if i were to just get more compression? or if i were to stroke it but have lower compression?

Stroking it gets you more CI and that wins

Posted By: HotRodDave

Re: piston out of deck????'s - 01/06/11 02:16 AM

depends on how much compression and displacement we are talking about.

Posted By: sixpakdodge

Re: piston out of deck????'s - 01/06/11 02:33 AM

I ran a .055 over 440 with the piston .013 out of the hole. It loved head gaskets.

It burned through a set of the .055 Cometic's right near the dowel pin, just like it did to the 1009 Fel Pro's I originally had on it. I had a set of .066 Cometic's on it when the block split due to fatigue. (Block had A LOT of runs on it.) I kept going thicker in attempt to lower the compression. It didn't make much of a difference though, the car ran the same. I was running 452 open chamber heads that were milled, but still open chambered, with flat top pistons.

Definitely check, double check, triple check, and then check again, the piston to valve/head clearance. I didn't have any problems with the piston to valve or piston to head, but it's very crucial.

Posted By: hemigod426

Re: piston out of deck????'s - 01/06/11 02:40 AM

Quote:

not going to blow head gaskets like the first machine shop says??

last i looked my hemis are way positve deck, is that gunna blow headgaskets, all ls1 350s are out of the hole for flat top pistons factory, run from that shop...

Posted By: dOoC

Re: piston out of deck????'s - 01/06/11 01:24 PM

Quote:

Quote:

not going to blow head gaskets like the first machine shop says??

What SOME of these so-called "professionals" say is flat-out SCAREY sometimes.

Posted By: polyspheric

Re: piston out of deck????'s - 01/06/11 04:07 PM

What SOME of these so-called "professionals" say is flat-out SCAREY sometimes.

True, dat.
Remember: "I do it for money" is what makes you a professional - not being good at it.
Look at Congress...

Posted By: Cab_Burge

Re: piston out of deck????'s - 01/06/11 06:39 PM

Quote:

another quick question, not tyring to start a debate war here just wondering... will i make more power if i were to just get more compression? or if i were to stroke it but have lower compression?

You can get the same results HP and torque wise from either choice. A stroker motor with less compression will be able to use pump gas and have a bunch more torque than the smaller motor with more compression running race gas with the same HP

Been there, done that

452 C.I.with 906 heads with 14.7 to 1 compression using C14+ made 625 HP, 610 ft. lbs

Two years later 512 C.I. with similar 906 heads with 9.25 to 1 comp. ratio made 612 HP and 644 FT lbs on pump gas

Strokers

good

Posted By: hemigod426

Re: piston out of deck????'s - 01/06/11 06:53 PM

Quote:

i am planning on a stroker build, and the build will put the pistons 0.020 out of the hole. is this going to be a problem, with the head and gasket i will have enough piston to valve clearance so thats not an issue. it will have a mild 11 to one comp... one machine shop says it will blows the gasket out all the time and i should not do this... another says some engines from the factory do it all day with out an issue. so who do i believe?

ill level with y'all it is a 4 cyl honda engine. so there is ample head bolts to keep it snug. this is my rice.

just curious what block and what piston for stoker motor is .020 out of deck? every 440 piston ive seen for is .010-.080 down from deck.

Posted By: StripeHOG

Re: piston out of deck????'s - 01/06/11 08:13 PM

in a honda

Posted By: Bob_Coomer

Re: piston out of deck????'s - 01/06/11 11:40 PM

what kind of engine? What kind of pistons, and heads? The machine shop you speak of, doesnt give trust worthy answers, my guess is there machine work isnt trust worthy either.
Talking about a .020 positive piston to deck clearance then referring to piston to valve questions is a bit confusing. This needs checked also, but piston to head is more critical in this much positive piston height than valve to piston....
Both need checked at any rate.
Is this a pump gas engine, or suppose to be? I haven't seen anyone ask yet, but having that much piston height is going to increase the compression a bunch.
Running 11:1+ compression will cost you power, and cause engine damage running today's pump gas.
Where a properly tuned 9.5:1 engine with the correct/optimal spark timing will not only make more power, but be more dependable any way you slice it.
More isn't always best in a performance engine.

Posted By: rice2muscle

Re: piston out of deck????'s - 01/07/11 09:32 PM

it is a honda 2.2 ltr. sorry.... please forgive me
but i can drop in a crank with 5mm longer stroke and the rods to go with it with my stock pistons. putting it 20 thous out of the hole.giving me a compression ratio of 10.98 to one. right now its like .006 in the hole with under 10 to one. yes its all aluminum with a knock sensor. i know this build is done, i was just wanted to know what some real car guys thought about it. not what the average honda enthusist thinks... (they are mostly idiots)

Posted By: 602heavy

Re: piston out of deck????'s - 01/07/11 10:03 PM

Some engines are designed to have the piston 5mm +/- out the hole in order to reduce peak cylinder pressure loading on head gasket just after TDC..............now if the guy who quoted this would come on in i'm sure you'd get the full picture.

Posted By: Bob_Coomer

Re: piston out of deck????'s - 01/07/11 10:05 PM

well your pushing the limits with pump gas even with aluminum heads.
I will take a guess and say the ignition system is computer controlled closed lop system that constantly monitors engine spark and knock, detonation, and pre ignition.
If the computer see's one of these problems it will just pull a bunch of timing out of the engine to help out. This is bad for performance. Lets say the same engine with less compression around (lets say 10:1) now has the same thing going on but the computer doesnt see any spark knock. The engine is operating at full potential and optimal timing. The lower compression engine now will out run the engine with more compression every time like this.
My 01 SS Camaro would detect a knock and pull timing out until I fill the fuel tank up. This is a decade old technology BTW.
On out V-8's a engine making good power at say 34-36 deg total timing will loose a easy 5% maybe as much as 10% if you pull the timing down 10 deg to 24-26 deg easy.
So in this case the increased compression's gain in power is offset more by the now none optimal timing curve...
Plus nothing will kill a engine quicker than pre ignition, and detonation.
Just some food for thought.
Later
Bob
Just drop my old engine in between the Honda's fenders and dont worry about it

Posted By: rice2muscle

Re: piston out of deck????'s - 01/08/11 05:09 PM

ive actually taken some measurements for my rb into the 2000 lb honda... i would have to take the firewall back like 16 inches and make a huge tranny tunnel.... then i have a short wheel base and that does not seems super stable at high speeds. but ive thought about it.

Posted By: polyspheric

Re: piston out of deck????'s - 01/08/11 05:27 PM

a crank with 5mm longer stroke and the rods to go with it with my stock pistons

Are the rods 2.5mm shorter than stock?

Posted By: HotRodDave

Re: piston out of deck????'s - 01/08/11 05:48 PM

Some reason those little motors always seem to be able to run way more compression than our big motors, I used to work at a Honda dealer and all the tuner guys working there were typically running 12 to 1 or even more on pump gas with ZERO issues, heck my dads 97 Geo metro would crank 220 PSI bone stock and runs better on 87 than 93

I think it has to do with the aluminum motors preventing hot spots, tiny bores and high RPM they would turn but somehow they got away with some crazy cylinder pressure

Posted By: rice2muscle

Re: piston out of deck????'s - 01/10/11 05:48 AM

Quote:

a crank with 5mm longer stroke and the rods to go with it with my stock pistons

Are the rods 2.5mm shorter than stock?

the crank is 4.3 mm longer of a stroke and the rods are 1.5 mm shorter.