'79 Block and stroker bore

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Jax

Jax

FABO Gold Member
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I was reading the book Big Inch Mopar Small Blocks.

The book mentioned that the '75 and later 360 blocks should be bored up to 0.030 over.

I have a 4179930-360 engine block year '79. And I already had it bored for my 4.040 pistons.:eek:ops:

I wasn't aware of this statement from the book.

What are your thoughts and experiences? I am ready to start the engine build and just found about this....:pale:
 
I just answered this in your other thread.

Sonic check the block for the actual amount of material left. If your machinist OK's the block for more, just know how much more and the con's that come with it. It maybe possible to get/find a kit with .040 pistons.

Forged slugs will be fitted at every cylinder for that cylinder. Cast/Hyper slugs are not normally done this way. Hypers expand less than forged slugs but require a tighter fitting.
 
do not lose a single minute of sleep, this is just a general suggestion, 4.040-4.030=.010", which is .005 thinner wall=the thickness of 5 pieces of paper
 
The block is already bored to 0.040. Linged honed and everthing else...

I need to dinf out if our local machinist can perform sonic testing on the block.

If not what do you recommend me to do?

I live in Aruba and I doubt that the local machine shops can perform this task.
 
Jax said:
The block is already bored to 0.040. Linged honed and everthing else...

I need to dinf out if our local machinist can perform sonic testing on the block.

If not what do you recommend me to do?

I live in Aruba and I doubt that the local machine shops can perform this task.
Click to expand...

I would imagine machine shops in Aruba follow the same guidelines as shops in America

step one should ALWAYS be sonic checking so if you were here, in the US, I would expect this to have been done before it was bored

I would just ask the guy
in my book, if he cant sonic check a block, he has no business touching one
 
Guys... I was able to contact the machine shop and he is able to perform the sonic test.

I will drop the block to his shop tomorrow and take the readings.

what are the minimum thickness I should consider?

Thanks
 
Yes... he is a capable shop... It was my bad...

I will keep you informed... What are the thickness limits,?
 
how much power are U planning on? the thickness limits are debatable, I would run it, and not waste the $ on a sonic check. many 360 engines in NHRA of all years go +.040"
 
Marcohotrod said:
how much power are U planning on? the thickness limits are debatable, I would run it, and not waste the $ on a sonic check. many 360 engines in NHRA of all years go +.040"
Click to expand...

Shooting around atleast 500 to 550 to the wheels
 
like stated above .....the diff. between .030 and .040 is only .005 per side., don't sweat too much over it Remember the outside of that bore dia is cast which can vary quite a bit compared to machined bore. - blocks could have core shift, etc when poured which could alter wall thickness
 
500 to 550 at the wheels??? Everything better be spot on on that engine. With that much HP I would sonic it. Don't quote me but I think you want at least .150 on the thrust sides, measure at least 12 spots per cylinder your machinist should know.
 
EXcappa said:
What heads, cam, comp?
I really doubt you will make that much power at the wheels
Click to expand...

Procomp Aluminum Heads Full CNC ported with double springs and dampers. 2.055-1.62 valves.
Cam Intake Valve Lift 1.6
Exhaust Valve Lift 1.6 .600"
.610"
Intake Opening at .050"
Exhaust Opening at .050" 21° BTC
55° BBC
Solid Roller lifters.
M1 Intake

Compression will be 11.1
 
Good news... The results are positive.

To recap: Thrust Sides 0.265 to 0.300
Non Thrust Sides 0.240 to 0.275

The block is within limits
 
Oh hey! That's great!

EXcappa
Originally Posted by Jax
Shooting around atleast 500 to 550 to the wheels
Click to expand...
That would be a approx. A 600HP engine.

Jax. What trans is going to be used? And gear?
 
those are some good cylinder wall numbers! I need to look for a '79 block!
 
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