What is a 3 & 9/16 engine

[3dinter]

i might of meant to say 9/16 stroker, im not sure what they call it....all i could hear from him was ground the crank to 2" and use some 327 rods..it was loud at his shop.....took my old block to the machine shop today and the guy was talking to me about building a 3 & 9/16 engine....sounded like a pretty good engine....what makes up this sorta engine ?

[fast_crew]

Offset grinding the crank to 3.625 (9/16)

[rubbinsracin]

What's the benefit?

[sj valley dave]

We ran a 3.5625 or a 9/16" stoker back in the early 90's when a track we raced at had a 365" limit in their Street Stocks. Ran great with a old set of 292 turbo castings..lol, a few more cubes and like the above poster said, little longer stroke than a stoke 3.48

[3dinter]

it seems to be the new thing around here the 3 9/16 or what ever you call them....we are limited to a 377 cu limit & 175 lbs of compression, no de-stroked or stroked...my machinest said something like grinding the crank to 2" and using 327 rods, etc, etc, etc...unsure about going this route...but like everyone i wanna win and around here you aint winnin unless your cheating..!!

[fast_crew]

Actually it's 3.562 (3 9/16).......3.625 is 3 5/8.

They do that alot in classes that have cubic inch limits but still have to use a 350 block. Gives you a longer stroke that helps get off the corners better.


My bad there ( in a hurry), right numbers wrong order ;) You knew what I meant though.

[dirttrackrocker]

Well, if they are running 3 9/16 stroke cranks and the rules say no stroked or destroked, then they are cheating. A 3 9/16 crank is stroked.

[sj valley dave]

If you have to run the stock stroke with the correct block, you really can't do much and be legal...As dirttrackrocker posted, if you have to have a 3.48 stroke in it, you are crossing the rules with the 9/16 deal...

[3dinter]

I understand completely...but we was legal by the rules all of last year, with the best driver around here and we would get almost lapped...so that obviously told us something and whats the old saying "if you cant beat them join them" so i think we have to join them in a few aspects of our racing this year.

[stockcar5]

you obviously dont have the best driver around if you think another 1/16 inch of stroke is gonna take you from almost a lap down to being competitive.

[DaveBauerSS6]

it seems to be the new thing around here the 3 9/16 or what ever you call them....we are limited to a 377 cu limit & 175 lbs of compression, no de-stroked or stroked...my machinest said something like grinding the crank to 2" and using 327 rods, etc, etc, etc...unsure about going this route...but like everyone i wanna win and around here you aint winnin unless your cheating..!!

You need to read your rules carefully. The 377 is a 400 block and a 350 crank. I would rather run the 377 than the 3 9/16 motor,

[powerslide]

You need to read your rules carefully. The 377 is a 400 block and a 350 crank. I would rather run the 377 than the 3 9/16 motor,
Also a 377 is destroked though so according to his rules still illegal. I find it odd they chose that number for the CI limit w/ the stoke rule.
I have heard old the old timers talk about some 350 blocks you could punch out to fit a 400 piston. I think they were half filling the block so it didnt bust. This by the way your rules are written sounds like a legal alternative.
I would suggest posting your engine rules verbatim so they can we can look at them and make an educated guess

[ka_jd7and1]

I find it odd they chose that number for the CI limit w/ the stoke rule.

Maybe they wrote the rule so it would still fit someone who isn't running a Chevy?

[3dinter]

here is our 2012 rules, my bad...not sure where i got 377 max cub's.
ENGINE: Must be stock for the make and model except no 400’s or larger small or big blocks.
All engine components including water pumps, distributor, etc., must be strictly stock. Cast
piston only, Chevy must use 4 equal valve relief pistons. Aftermarket mini starter, pulleys,
harmonic balancer and oil pans okay. Aftermarket power-steering pumps okay. Metric cars may
run a 350. NO stroking or de-stroking. Engine must be in stock location. Solid motor and
transmission mounts okay. Maximum cranking compression 175 lbs.(ignition off, engine turned
over 5 times).
CAMSHAFT, VALVETRAIN, AND CYLINDER HEADS: Hydraulic cam and lifters only.
.447 maximum lift. Must maintain 14” of vacuum at 1200 rpm. 1.94 maximum intake valve
diameter, 1.50 maximum exhaust valve diameter on Chevrolet engines. Stock size valve springs
and stock length pushrods only. Stamped steel 1.5 rockers on Chevy , 1.6 on Ford and Chrysler,
NO roller tips. Open chambered heads only, must be unaltered, O.E.M. NO porting, polishing, or
gasket matching allowed. Screw in studs and guide plates ok. 305 engines may use 305 heads(no
vortec).
CARBURATION AND FUEL SYSTEM: Holley 4412 2-barrel only. Must be unaltered.
Choke plate may be removed. 4412 must be cast into body of carb. Maximum spacer and adapter
1” combined total. Fuel pump must be in stock location for make, NO electric pumps or fuel
injection even if factory equipped.
EXHAUST: Stock unaltered cast iron exhaust manifolds only. NO Chevy center dump,
Corvette, marine, or tubular steel type manifolds. Exhaust must remain dual, NO crossover, Ypipe,
or 2-in-1 pipes. Mufflers required.
INTAKE MANIFOLD: Stock unaltered aluminum or cast iron intake only. NO aftermarket or
stock high performance or high rise. NO bowties. NO porting, polishing, or gasket matching.