Is it necessary to have a block sonic tested before building a 350 street motor? My target is 350-400hp and torque?
Now I have a 350 with that casting number. Your saying with a standard bore I dont have to sonic test, I can achieve those numbers.If it were me and I had a 3970010 350 block that is a standard bore that needed to be bored .030 or .040 I would not have the sonic test done. Now if the block has been bored and I needed to have it bored again I would have it done. If I had a standard bore block and wanted it bored .060 I would have the test done.
I've had sonic tested blocks blow the webbing onto the track,through the pan.. and had a 50 junker run 3 seasons on spray...
it's the luck of the draw..
even when some blocks don't pass the test.. it's not that a 13 to 1 n/a engine will have the pressure build to blow a whole in the wall..
detonation does that..
WOW I have been sonic testing for 30 plus years now and still in business What are you doing wrong ?????????We are talking a 350-400 hp engine here. Plus no oversize stated. A very common situation.
Yes, weak cylinder walls can be found in production blocks and old blocks. I have had new blocks sonic checked and still unusable from sand/air inclusions (one a mexican block from Summit). Just had a 283 from an old boat checked and it was junk from massive corrosion in water side of cylinder walls .
But, for the average guy building a 350 street engine. I will not insist on sonic check.. If I did. I would have been out of business 45 years ago..
The quality of Mexican block is not as good as the ones I bought out of the Tanawanda plant in NY. I am talking about machine work like cylinder bore placement, lifter bore placement and cam tunnel placement and deck heights ETC.Please discuss further:
1) The quality of mexiblocks.
2) Sonic testing in further detail.
no need for a search. 25 years of racing..At finish size I look for minimum of .160 on the skirt sides and wrist pin side I look for a minimum of .100 at finish is size.
I have seen guys with stock builds crack the wall of a cylinder and I doubt it was 13:01
Do a search!!
I would get one done If you want a reliable build unless you have a crystal ball or take a guess like others have said.Thank you all for the details on my block. So it looks like I don't need to have a sonic test done. I want a reliable street engine 350-400hp and torque.
35 plus years of racing and building racing engines I see to many junk blocks because of thin cylinders.no need for a search. 25 years of racing..
luck of the draw
guys, what if i had a big block 454 and I wanted 400hp and torque? do i need a sonic test as well?