[4Bangn S10]

im doing my v8 swop after christmas and was wondering if i can run these pistions on pump gas if not what compression would i be able to i wont the hights compression i can get


http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=2449728370&category=33623

 

[MoNkEyZQ8]

whoa.. 13.1 compression..

That would require pretty high octane..

 

[4Bangn S10]

thats what i thought

 

[4Bangn S10]

and will any SBC pistion fit a 327 i think they will but not sure

 

[Rhansen]

Those pistons wont work in a 327. 302,327,350 all 4" bore - 400 is bigger bore ?4.125? I think.

 

[4Bangn S10]

ok thanx

 

[RANDY406]

It's not just the bore size that matters.All smallblock Chevy's come stock with 5.7" rods except,the 400 5.565".So,the pin heighth(where the rod connects to the piston) is different from engine to engine.A 350 has a 3.48" stroke a 327 has a 3.25"stroke.Both have a 4.00" bore.If you put a 327 piston in a 350 it will stick out the top of the block .23". if you reverse it the 350 piston would be .23 down in the block.

 

[4Bangn S10]

so i should got a 327 pistion


when i called in the number on the block he said it was eather a 302,327,or a 350 he said i had to get the number from the crank and it was a 327 steel crank why did it show up as 3 diff sizes if there all diff

 

[RANDY406]

Yep,that's all that will fit with your 327 block,and crank

 

[4Bangn S10]

but what i dont get i y i have 3 diff engin sizes the guy said i could get a 350 crank and make it a 350 if i wonted to

 

[RANDY406]

That's because the blocks are basically the same.This is the greatest part about Chevy's interchangeability!Only the 400 is different it has siamesed bores (no water can flow between cylinders,they touch in the middle).This was done to keep the center line the same (between the pistons)as all other smallblocks.

Here are some combo's
Bore Stroke
283 3 7/8 3.00
302 4.0 3.00
305 3.736 3.48
307 3 7/8 3.25
327 4.0 3.25
350 4.0 3.48
400 4.125 3.75

These are stock combo's.Put a 400 crank in 350 block punch it .030 and you'll have a 383.

Put a 350 crank in a 400 .030 over and you get a 377

400 crank in a 305 +.030=331

you see there are many options just be careful.327's built 1967 or earlier have a smaller main and rod journal.2.30 main 2.00 rod.After 68 they are 2.45 main and 2.10 ,rods all 350's have the larger journals. So, you have to find a 68 or 69 block with the large journals for it to fit without alot of cutting on the crank.You can also buy after market cranks w/any stroke ,journal size you want.

 

[4Bangn S10]

it came out of a 1973 chevy dump truck


thanx for all ur help i will post pix of the install and the motor

 

[RANDY406]

If it came from a 73 dump truck it is either not the original motor or,it's not a 327.They quit making 327 in 69.

 

[4Bangn S10]

i dont know for sure if its out of a 73 ill find out tomarrow

 

[4Bangn S10]

just asked my dad he said it was eather a 67 or 68

 

[RANDY406]

Goodluck.

BTW,go to your local bookstore you'll be amazed at how many books you can find with all the info you need for smallblock Chevy's

 

[4Bangn S10]

i ment i dont know for sure if its out of a 73

 

[4Bangn S10]

i know its a 327

 

[rick]

building a street engine

If the crank is o.k. use it.If you are doing a full tilt rebuild,then get yourself a 383 kit and take advantage of the cubes and low end torque. I prefer flat top pistons over domes,do some research on "Quench". The rule of thumb is no more than 9.5 to 1 with iron heads and 10.5 to 1 with aluminum .These specs are for premium gas,and you will need to check you dynamic comp.ratio to make sure you are on the safe side of things.The cam you chose to run will affect the "running comp.ratio "or dynamic ratio.The type of piston,deck height ,chamber size and gasket will give you your static comp.. Useing modern cam grinds will allow you to make excellent power ,while retaining a streetable low comp.ratio,and allow you to run on pump gas.You may want to have the heads checked for cracks between the center cylinder exhaust ports,they did like to crack ,and I don,t think that they have hardened valve seats either. the newer vortecs make a nice street head and can be had cheap.

 

[4Bangn S10]

all that im going to do to it


327 block 40 over


stock steal crank [for the rear 327]


a racing cam from comp cams [email protected]" lift 525/525 lobesep 110
heads sent out and checked 3 angle valve job exh 2.020 int1.600


roller rockers crane cams roller lifters


speed pro hypereutectic pistons [40 over]


edelbrock air gap intake


edelbrock 750 CFM carb


hopefully it will have 400 to 450 hp do yall think it will