who runs 13sec to 12.80 in the 1/4

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DusterBoy15 said:
well i guess i have to bite this one i really dont want to but the guy called me a dumb ***


and no one answerd me if i can shave the heads to raise compression with these pistons and if not i guess im going to get kb 10 pistons
Click to expand...

Actually, I'd characterize it more as "pig headed". You'll grow out of it eventually. You were told from the get go what to look for, and where to find the info you seek. You chose to trust a stranger you now call "Mr Dick". So, you're now upset, and back asking "what should I do", getting solid answers, and still sticking to your own guns. SO, for humor's sake..

You could mill the heads to get static ratio back. But, this get's you into areas like milling to ge the intake to fit right, and replaceing pushrods and/or shimming the rocker sahfts to keep the thing running well after you save $200. What you could do is simply downsize the cam, and get the package that will run the number, should you choose to take the initiative and spend time learning (that means NOT asking for validation of your ideas, but to soak up others' ideas and then think about it) about how the package works. Or, you could replace the pistons with something better. I didnt suggest hypers because if the engine was already rebuilt, the wall cleanrance my not be right with KB hypers. You could simply stuff ina set of forged pistons easy tho. Also, with a piston cahnge, you MUST rebalance the assembly. So you'll have the cost of honing, cleaning, cam bearings replacement, and balancing to your budget. Personaly, if you stuffed a smaller cam like the ones you were told about in it, changed the springs to match, and ran it, you'd be close to where you want to be without the heartache Mr Dick "caused".
 
here are some pics of the motor i cleaned just the pistons up not the walls

also would that oil pan work in a abody???

blah.jpg


pan.jpg


piston.jpg


pis.jpg
 
Nope that is a rear sump......you need a center sump. And by those pics...I would say that motor was not recently rebuilt.....or ever at all. You need to get a couple of good books and do some reading in study hall......Hot to Hot Rod Small Block Mopars would be a good start. We were all in your shoes at one point you have an advantage.....you can get online and ask questions before you buy parts.
 
yes i do need pistons im looking to get some speed pro pistons .030 over balance the set up and use a thin gasket to get up to 9.1-9,5 compression
 
Thats a stock truck motor if I have ever seen one. Are you sure its a 360 ?
 
moper said:
Quote:
Originally Posted by DusterBoy15
well i guess i have to bite this one i really dont want to but the guy called me a dumb ***
Click to expand...

and no one answerd me if i can shave the heads to raise compression with these pistons and if not i guess im going to get kb 10 pistons

Actually, I'd characterize it more as "pig headed". You'll grow out of it eventually. You were told from the get go what to look for, and where to find the info you seek. You chose to trust a stranger you now call "Mr Dick". So, you're now upset, and back asking "what should I do", getting solid answers, and still sticking to your own guns.
Click to expand...

Well said, somehow, young age may still yet get in the way.
 
yes i know but as i read more i will learn thanks to you guys but i will be doing the above setup with speed pro hyper pistons and thinner gasket since i have to bored the motor anyways and and balance then we will see what else needs to be done
 
You may not need the thinner gaskets. It is a combo of piston height, head cc amount and gasket thickness and bore that will detremin the ratio. The gasket thickness is a minor adjustment to the overall ratio.

example, A 360, .030 zero deck 5cc piston relief piston and stock 360, 72 cc heads with a .039 gasket @ 4.10 bore is 10.30 -1 ratio.

Changing the gasket thickness wil look like this;
.060 = 9.81 -1
.020 = 10.80 - 1


Notice there a .040 difference in gasket thickness for 1 point of compresion.

The same above starting example with cylinder head cc change;
72 cc sarts at 10.30-1
72 down to 65 = 11.19-1 ratio.
72 up to 85 = 9.01 - 1 ratio.

Same starting example only with piston height change

10.30 to start, down .050 and then down to .100

-.010 down the hole, = 10.07 - 1
-.020 down the hole, = 9.84 - 1
-.030 down the hole, = 9.63 - 1
-.040 down the hole, = 9.43 - 1

Can you see how wide and varied it can become?
This is why most people here will recomend a zero deck piston to start with. It gets the compresion up very close to where most performance engine will want to start with. It avoids head milling issues that crop up like bolt hole alignment.
There are other pistons on the market that are down the hole .010 to start with.
This is based on the 9.58 or 9.6 deck height. This will also vary. The actuall deck height and what the piston makers bases the piston height on.

Confused? Thats why there machinests. I use'em. He he he. I can't afford the tools and time needed to do the major amount of work needed to build up a ace engine. This is where I am very happy to save and pay for there services.
 
i get you and here is the info on the pistons

Federal Mogul/Speed Pro Piston Part
Number

Application Power Range Special requirements Compression information
Ring groove size

Pin diamater
Rod length

Stroke
Deck clearance

Skirt clearance



H405CP030 and a FREE set of Perfect Circle 50564CP030 rings



Magazines get $144 a set for the pistons alone $18.69 ea.
360 Chrysler 4.030" bore 1967-2003 flat with 4 valve reliefs


idle to 6000+rpm Good for street or light race/nitrous to 75 shot 1.637 compression distance

Approx. Compression (@.030"):

w/63cc heads 9.11:1

w/65cc heads 8.94:1
5/64" 5/64" 3/16" ring grooves

.984" pin diam.
6.123" rods

press fit only

3.580" stroke
.050" deck clr

.0015" skirt clr
 
I HIGHLY recommend that before you buy absolutely any parts for that motor, that you purchase and thoroughly study the book in the link below. This will be the smartest money you will spend, and will give you enough information to put together a complete plan of how you want your engine to be after all the work is done to it. Otherwise you'll be throwing good money after bad. Hows that saying go? Screw me once, shame on you, screw me twice, shame on me. Get a complete plan before you go out and buy a bunch of parts that may not be what you really need. JMO. Mike

http://cgi.ebay.com/ebaymotors/HOW-...4663290QQihZ016QQcategoryZ46098QQcmdZViewItem
 
DusterBoy15 said:
yes i know but as i read more i will learn thanks to you guys but i will be doing the above setup with speed pro hyper pistons and thinner gasket since i have to bored the motor anyways and and balance then we will see what else needs to be done
Click to expand...

Remember to get the cylinders checked out BEFORE you order the pistons.

also, don't assume that your heads are going to be 63-65cc, you will need to get those checked as well.

Stock 360 heads 72-73cc.
 
Good advice above.

See the approx. ratios? With what gasket? Remember, you can order a comteic gasket @ 4.040 bore and .060 thick or use a mopar thin gasket @ .028 thick and whatever the bore size is it comes in.

@ (lets round it off.) a .030 thickness difference and possible deck differences. It could vary like by as much as;

10.61-1 to 9,85-1 on gaskets alone.
9.43 - 1 @ .020 w/piston being down the hole or even worse, if the block is 9.6 vs 9.58. Before you know it, your ratio is 9.0-1 with the pistons listed @ 9.8-1.
 
vmike: i have the book and read it
ok i will check the heads
and ADAM yes i would buy those head sep for there like 200 with out rings
when these are half the price with rings and what i need to do is get the blocked honed and check the bore size
 
just remember - you get what you pay for

and junk in = junk out

weather or not you realize it your on your way into your first full blown rebuild... like it or not

mite as well make it a learning experience and do it right the first time
 
Those speed pro pistons are cheap because they are no better than the stock pistons.....they will sit down in the hole just like the stock ones. Get the KB's save the money up and buy the rings......it might take you longer but you'll be happier with the motor in the long run. Patence there young one.....If I can learn it anyone can.
 
The problem that I see is that he's trying to run on pump gas and keep the compression to 9.5:1, this isn't going to be a race engine, but more street and a DD. And the type of fuel that he'll have to use and with the budget of a youngster, the KB107's would be out. If he square decks the engine and uses the thinner gaskets and runs the small chamber heads like the 318's that he has then he should be in the range of 9.5 or better. He's not wanting to turn this engine over 5500 or 6000 rpms. And then only a couple of times a year at a race track, most of his driving will be 4000 rpm's or less most of the time.
He needs to listen to a good machinist that know whats going on with mopars, and his wallet. As it's fine for all of us to say what we would do but were not the one's thats having to spend the money or on his budget. Only he knows this.
I agree that he's young and is learning and we don't want him to make any mistakes, and planning a engine takes time and some changes to work out to achieve the out come that he wants.
 
ValiantMike said:
I HIGHLY recommend that before you buy absolutely any parts for that motor, that you purchase and thoroughly study the book in the link below. This will be the smartest money you will spend, and will give you enough information to put together a complete plan of how you want your engine to be after all the work is done to it. Otherwise you'll be throwing good money after bad. Hows that saying go? Screw me once, shame on you, screw me twice, shame on me. Get a complete plan before you go out and buy a bunch of parts that may not be what you really need. JMO. Mike

http://cgi.ebay.com/ebaymotors/HOW-...4663290QQihZ016QQcategoryZ46098QQcmdZViewItem
Click to expand...

Why read the book when you can ask the kid next to you in English class what its about? :-D Seriously, re-read it then, most to all the questions you ask are answered there.
 
If he goes with the speed pros and the small chamber 318 heads and later decides he wants to step up the power then what ? Toatal rebuild again?

The 107s even if he set them at zero deck with the 360 heads should be pump gas friendly.

With the speed Pros way down in the hole, a think gasket and small chambers he could end up with terrible quench and still have detanation problems. Been there before with a 440. It had low compression TRWs (2266) think .024"gaskets and milled 346 heads. Maybe 9.8:1 compression. It hated pump gas even with a good size cam.

I do agree he needs a good machine shop to help but he should be building a short block that not only fits his budget but can be upgraded later.

If he doesnt deck the block for zero deck he should be at 10:1 with a 68cc head and a .040" gasket

The Speed Pros would be just over 9:1

If he uses small chamber 318 heads (62cc?) and the think .027" gaskets he'll be at the same 10:1. Now if he decides to go to a Edelbrock head later hes going to loose some compression becuase the chambers are bigger then the 318 heads.
 
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