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Author Topic:   9/16 th's Motor?
Kromulous
Member
posted May 27, 2004 01:02 PM
Anyone know what these are? I have heard some old time engine builders refer to them, and they all seem to love them.

9/16th's i assume is the stroke, but not to sure.

dode
Member
posted May 27, 2004 01:44 PM
yes, it is a SBC with a 3.5625" stroke as opposed to 3.48".

John

Kromulous
Member
posted May 27, 2004 02:47 PM
Thanks, thought so but wanted to be sure.

Anyone ever run one, like them?

racer17j
Member
posted May 27, 2004 04:52 PM
we have a kid in my class that runs one we are under 360 cid 9-1 comp rules and he is bad fast either wins or wrecks


rico 08
Member
posted May 27, 2004 07:31 PM
I had one(363)was really a good motor,perfect for a 360 cid rule if they give you a 1% fudge factor.


M1
Member
posted May 28, 2004 08:55 AM
how do they aceive the longer stroke? Offset grind the journals?


dirtbuster
Member
posted May 28, 2004 09:48 AM
Yeah you can either offset grind a 350 crank and use small journal rods or nowadays you can buy a 3.5625 stroke crank with standard journals, as well as a 3.625 if you wanted. A lot of piston makers also have standard pistons for these combos now so they are easier to put together. Pick a stroke, rod length and piston to match and your done.


racer17j
Member
posted May 28, 2004 05:44 PM
they aren'y cheap tho the pistons alone run you around 300


engineman
Member
posted May 29, 2004 05:19 AM
I build them all the time, I love em!!! I have gone both ways....aftermarket crank, and I have offset ground some. both work great!

BTW... "King" makes a rod bearing that will let you use a large journal rod on a small journal crank. They are some "big ole thick things" and a little heavy, but we have built some 500 + HP motors that turned around 7500rpm without any trouble.

If your trying to build a "cheap claimer" that will make good power,you can get creative and use a standard 3.48 stroke "off the shelf" piston with a short deck height(like .025)and use thick head gaskets to get the quench right(I try to get it around .028 to .035 on a steel rod motor depending on cylinder clearances,JMHO)

A 3.562 stroke will only move the piston up around .040, and with a .025 deck height standard stroke piston, it will put the piston out of the hole around .015 (on a non decked block)so depending on what piston you use, and how much you have to cut off the block to clean up the deck, you can use a cheap "thick" head gasket like a "Corecto" or a thick MLS gasket(not so cheap!)to get the quench right.

I have built a BUNCH of race winning "Claimers" like this,and it works great, just takes a little thinking to get everything right,and to keep the cost down.

I hope some of this is helpful,and if you have any questions you can e-mail me.

Mark T.

Mark's Racing Engines
www.northtexasracing.com
engineman@northtexasracing.com

[This message has been edited by engineman (edited May 29, 2004).]

Okie11m
Member
posted May 29, 2004 03:08 PM
Where are you located Mark?


engineman
Member
posted May 29, 2004 04:30 PM
I'm around Greenville TX.


Kromulous
Member
posted June 01, 2004 11:26 AM
Whats the journal size end up at when you offset grind a stock steel crank into a 3.5625 stroke? 1.888 ?

Trying to locate some rods for this combo now.

Kromulous
Member
posted June 01, 2004 01:01 PM
What does the rod journal size end up once you offset grind a stock stroke crank? 1.88?


15a
Member
posted June 01, 2004 01:03 PM
Thanks again all, for the great info.


dirtbuster
Member
posted June 01, 2004 02:10 PM
JE/SRP pistons, SCAT crankshafts as well as others i am sure.


stevenmw
Member
posted June 01, 2004 02:53 PM
can someone post the names or websites of the companies building the after market crank rods and pistons

http://www.herbertperformance.com/

They carry just about anything to do with altering strokes on engines.

Enjoy.
Steven.

[This message has been edited by stevenmw (edited June 01, 2004).]

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