building a 360

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fishy68 said:
You need tools for checking the chamber cc's. I don't know if you do E-bay but if you do here is a cheap kit that'll do it. Just make sure and clean the chamber and valves good so you get an accurate reading.

http://cgi.ebay.com/ebaymotors/ws/e...0395360749&viewitem=&sspagename=STRK:MEWAX:IT

Then you check to see how far down the hole the pistons are. There are a few ways of doing it but I find TDC with a dial indicator then lay a straight edge across the deck surface and stack feeler gauge blades until you reach the piston then add them up and that's how far down the hole the piston is. If the pistons have valve reliefs that'll add cc's to the equation. They vary so it's best to look up the pistons and see what it's rated at since you can't really get in and cc them easily with the lower end together. Then you go to the website octanejunkie provided and plug in all the numbers and it'll give you your compression.
Click to expand...

FWIW I put my own CC kit together, I have a thread on it here with pics, it cost me all of $8 plus some grease and bottled water, of course you can use any liquid you want... just remember to be as consistent as possible with filling in the syringe and put the hole in the plexi plate at one "corner" of the chamber - I pitched the head in such a way that the air was forced to the corner where the hole was - easy peasy

Once you have all your chamber measurements (I did each chamber twice) you need the rest of the measurement as fishy described. For deck height I prefer a dial indicator on a magnetic base zeroed on the deck surface but the feeler gauge method works fine, I just don't like relying on having to compress multiple leaves of a gauge against a straight edge, too much margin for error IMO, unless you bolt the straight edge to the block. If you have a metal supply house near you get a rem piece of 1"x1" cold roll bar stock about 2' long and lay it across the length of the deck, use a few bolts and clamp it to the deck in the head bolt holes - if you are really industrious you can drill the bar and bolt through it - BTW this won't work too well if your pistons pop out of the bores, check that first ;) you want to measure the flat of the piston or the tallest point if it is a domed piston.

Once you have the deck heights of all 8 pistons, you can average them if they are super close (within .005 of each other) or use the smallest measurement you got as it will give you the highest compression value, then plug into the CR calc and off you go - erring on the side of caution is always better that is why you use the tallest piston rather than the deepest or a median measurement

As far as piston volume, look that up as fishy recommended, almost impossible to measure accurately at home. Then select a gasket like the fel-pro Z1008 (4.180" bore by .039" compressed thickness) or the Mopar P4120093 (4.060" x .040" compressed thickness) and you are pretty much there.
 
octanejunkie said:
FWIW I put my own CC kit together, I have a thread on it here with pics, it cost me all of $8 plus some grease and bottled water, of course you can use any liquid you want... just remember to be as consistent as possible with filling in the syringe and put the hole in the plexi plate at one "corner" of the chamber - I pitched the head in such a way that the air was forced to the corner where the hole was - easy peasy
Click to expand...

Where did you find a syringe big enough? I've looked for them and never had any luck finding anything very big. I already have the plexi glass and have been using a 100 cc beaker I got at the local drug store. It works but I think a syringe would be alot easier to manage.
 
fishy68 said:
Where did you find a syringe big enough? I've looked for them and never had any luck finding anything very big. I already have the plexi glass and have been using a 100 cc beaker I got at the local drug store. It works but I think a syringe would be alot easier to manage.
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I got two 60cc irrigation syringes from a medical supply place for $3. You can also get them from any livestock/veterinary supply or on the internet, plus shipping. You can see a pic of the item in question here

I also looked for a 100cc syringe but only found 60cc, so I did it in two passes filling the syringe to 40cc each time. The trick is to have the same bubble (meniscus) at the tip each time. If the bubble at the end of the tip isn't too big, the natural capillary action will hold it in place, even if you are just fairly gentle moving the syringe from fill site to drop site

Give me your address fishy and I'll send one your way if you like
 
octanejunkie said:
I got two 60cc irrigation syringes from a medical supply place for $3. You can also get them from any livestock/veterinary supply or on the internet, plus shipping. You can see a pic of the item in question here

I also looked for a 100cc syringe but only found 60cc, so I did it in two passes filling the syringe to 40cc each time. The trick is to have the same bubble (meniscus) at the tip each time. If the bubble at the end of the tip isn't too big, the natural capillary action will hold it in place, even if you are just fairly gentle moving the syringe from fill site to drop site

Give me your address fishy and I'll send one your way if you like
Click to expand...

Man that'd be great! Pm sent. Thanks
 
](*,)Guys I need a bit of help here.I am pulling a 318 out of my duster and putting in the 360.If i am correct the 360 is externaly balanced,so i assume I cant use my 318 flexplate.If I use my 360 flexplate I dont think it will bolt up to the torque converter.The trans is original and not sure which one it is.How can I get around this problem.If I use the 318 plate on my 360 it seems it would destroy the engine while causing a vibration.Will the 360 plate bolt up to the converter.
 
mynumber38 said:
](*,)Guys I need a bit of help here.I am pulling a 318 out of my duster and putting in the 360.If i am correct the 360 is externaly balanced,so i assume I cant use my 318 flexplate.If I use my 360 flexplate I dont think it will bolt up to the torque converter.The trans is original and not sure which one it is.How can I get around this problem.If I use the 318 plate on my 360 it seems it would destroy the engine while causing a vibration.Will the 360 plate bolt up to the converter.
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The flexplate from a 318 and 360 are the exact same so they will interchange but Mopar engines are not balanced by the flexplate like a Chevy. The 360 torque converter has balance weights welded on it to balance it for use on a 360. A 318 converter has no extra weighs. You can get around this problem by using a B&M flexplate designed to correctly balance your 360 using a 318 torque converter. You need to identify which trans you have to get the correct B&M balance plate. If the pan is rectangular it's a 904. If it is rectangular with a kicked out area on the passenger side it's a 727. If you have a 904 trans. the B&M part # you need is 10239 and if you have a 727 the part # is 10236. You can buy them from Summit or Jegs for about $76
 
fishy68 said:
The flexplate from a 318 and 360 are the exact same so they will interchange but Mopar engines are not balanced by the flexplate like a Chevy. The 360 torque converter has balance weights welded on it to balance it for use on a 360. A 318 converter has no extra weighs. You can get around this problem by using a B&M flexplate designed to correctly balance your 360 using a 318 torque converter. You need to identify which trans you have to get the correct B&M balance plate. If the pan is rectangular it's a 904. If it is rectangular with a kicked out area on the passenger side it's a 727. If you have a 904 trans. the B&M part # you need is 10239 and if you have a 727 the part # is 10236. You can buy them from Summit or Jegs for about $76
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Man fishy68 you have a wealth of knowledge.I do appreciate the info very much.You just set my mind at ease on this one.Thanks very much,Eddie.:cheers:
 
fishy68 said:
Glad to help Eddie.
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Hey fishy just a quick question.I had the block bored 40 over.The cylinder measures 4.037 and the gasket measures 4.145 with a thickness of .055 will this gaskett compress to 4.040 or should I buy new gasketts.I am not really worried to much about the thickness,just dont want the gaskett to cover and of the cylinder by compressing to far.Thanks,Eddie
 
mynumber38 said:
Hey fishy just a quick question.I had the block bored 40 over.The cylinder measures 4.037 and the gasket measures 4.145 with a thickness of .055 will this gaskett compress to 4.040 or should I buy new gasketts.I am not really worried to much about the thickness,just dont want the gaskett to cover and of the cylinder by compressing to far.Thanks,Eddie
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You'll be fine. I have never measured how much it compresses inward but I'm sure it's nowhere near that much.

BTW: Are you sure about the finished bore diameter? I'm not a machinist but I think the bore diameter should be 4.04 for a .040 over. The piston diameter is less to allow for clearance. If their forged pistons 4.036~4.037 is in the ballpark for what they should measure. Somebody please correct me if I'm wrong on this as I don't want to give bad information.
 
fishy68 said:
You'll be fine. I have never measured how much it compresses inward but I'm sure it's nowhere near that much.

BTW: Are you sure about the finished bore diameter? I'm not a machinist but I think the bore diameter should be 4.04 for a .040 over. The piston diameter is less to allow for clearance. If their forged pistons 4.036~4.037 is in the ballpark for what they should measure. Somebody please correct me if I'm wrong on this as I don't want to give bad information.
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I did use a caliper/micrometer to measure the cylinders and that is what I came up with.Now the caliper could be wrong,after all I did buy it at a harbor freight discount tool store.As for the pistons they were speedpro .040 flat tops with valve rieliefs.I dont think they are forged because they only cost me 250. and some change.I dont know much about forged or not forged.They could be a forged piston.Thanks for the info!
 
I would hazard a guess that the OP's measurement on the bore is off, .003" ain't that much to fudge with a regular caliper, regardless of it's source, you really need an inside mic or bore gauge

If there are concerns regarding the bore diameters or boring of the block I would contact the machinist/shop that did the work and ask what their tolerance is and whether they have any records of bore concentricity prior to their work, both parallel and perpendicular to the crank bore if possible

If you do call the shop I would also inquire into deck height, whether they took any measurements off the crank center line to the deck surface. Once you mock-up the build and measure piston-to-deck clearance you may want to mill the decks to square up your deck surfaces and set/tune your deck clearance, compression and quench.
 
Good ideas guys.

I would think a stock piston bottom end, given it's new, with .045 milled off the heads [of corse whats the current cc?] and .040 off the intake side, if you have to ..use the thin magnum intake gasket, 1 Step above a stock 340 cam like .468/268* or XE268*, rpm/ld340 dual plane intake, 650-700cfm carb, and headers would make 325-350hp
 
I am running speedpro .040 flat tops with valve rieliefs,280 474 purple cam-360 heads with 188 160 valves heads were milled 20, torker or air gap intake with 670 holley havent decided yet.I have installed clevite rod and main bearings.Also going to run headers,hoping to make 330 to 350 hp.The piston with number one up is real close to being flush with the top of the cylinder.What do you think of this combination,can I achieve my goal.Thanks,Eddie.
 
mynumber38 said:
I am running speedpro .040 flat tops with valve rieliefs,280 474 purple cam-360 heads with 188 160 valves heads were milled 20, torker or air gap intake with 670 holley havent decided yet.I have installed clevite rod and main bearings.Also going to run headers,hoping to make 330 to 350 hp.The piston with number one up is real close to being flush with the top of the cylinder.What do you think of this combination,can I achieve my goal.Thanks,Eddie.
Click to expand...

If you have the slugs in the holes you can measure your deck height (piston-to-deck clearance) and use the CR calc at kb-silvolite.com to calculate/estimate your CR - of course you will need to CC the combustion chambers of your heads and choose a gasket to work with as well as know the piston volume

All minor details add up, sometime considerably
 
:read2:
octanejunkie said:
If you have the slugs in the holes you can measure your deck height (piston-to-deck clearance) and use the CR calc at kb-silvolite.com to calculate/estimate your CR - of course you will need to CC the combustion chambers of your heads and choose a gasket to work with as well as know the piston volume

All minor details add up, sometime considerably
Click to expand...
Anyone know if the airgap intake with mopar breather will fit under the hood of the 70 Duster Im building.I want to run this intake but I dont want to buy it if it wont fit.
 
octanejunkie said:
If you have the slugs in the holes you can measure your deck height (piston-to-deck clearance) and use the CR calc at kb-silvolite.com to calculate/estimate your CR - of course you will need to CC the combustion chambers of your heads and choose a gasket to work with as well as know the piston volume

All minor details add up, sometime considerably
Click to expand...
I have a quick question,I installed my stock rockers today and it seems they are putting the push rods in a bind.They are stamped 31 rt 32 rt 32 Lt 33Lt I dont uderstand what this is.I know there seems to be a left and right.Is there something I am over looking,do you know of a web site I can check out.I seem to have them on right know but it seems like the rocker is not sitting center on the valve.If you need a picture of this send me your email and I will send you a pic,that is if you dont mind helping me out.Thanks,Eddie
 
mynumber38 said:
I have a quick question,I installed my stock rockers today and it seems they are putting the push rods in a bind.They are stamped 31 rt 32 rt 32 Lt 33Lt I dont uderstand what this is.I know there seems to be a left and right.Is there something I am over looking,do you know of a web site I can check out.I seem to have them on right know but it seems like the rocker is not sitting center on the valve.If you need a picture of this send me your email and I will send you a pic,that is if you dont mind helping me out.Thanks,Eddie
Click to expand...

Your correct that there is left and right and if not in the right place they won't be centered on the valves. I wish I had a pic to post but I don't. There pretty easy to decipher which way they go if you look at them. Move them around until you get them in alignment. As far as the numbers I have never noticed numbers stamped on them but in honesty I have never looked very close.
 
fishy68 said:
Your correct that there is left and right and if not in the right place they won't be centered on the valves. I wish I had a pic to post but I don't. There pretty easy to decipher which way they go if you look at them. Move them around until you get them in alignment. As far as the numbers I have never noticed numbers stamped on them but in honesty I have never looked very close.
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I will take them back off and move them around untill they seem to fit.They are on there now but dont seem to be center on the valve.Thanks,Eddie
 
fishy68 said:
That's what I did the first time I did one. You'll get it.
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Yeah it was pretty easy once I got into it.I marked the ones that were right on one side and the ones that were wrong on the other side and switched them and that was the fix.Thanks again.
 
so i am working on getting all the pieces together for a 360 build i think i am going to run kb107 pistons do i have to worry about the valves clearing the piston
 
spstacman said:
so i am working on getting all the pieces together for a 360 build i think i am going to run kb107 pistons do i have to worry about the valves clearing the piston
Click to expand...

That depends on many things, namely how much lift cam are you planning on running, what heads you are running and whether the pistons pop out of the bores, among other variables...
 
spstacman said:
so i am working on getting all the pieces together for a 360 build i think i am going to run kb107 pistons do i have to worry about the valves clearing the piston
Click to expand...
I think you can use clay to measure your clearance to valve during construction. You are not there yet imo.

Start a new thread with all your piston clearance questions as well as any others.

You will have 100x the exposure to the questions will have. Members have to stumble onto your questions this way. Just trying to help you out.
 
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