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X-block sonic test results

Posted By: mopster

X-block sonic test results - 12/27/13 01:55 AM

Iīm starting a small block build, half race half street use, n/a E85, around 13:1 compression. Iīm using X-block and plan is to use 4.125" crank and 4.08" bore. I need the block to handle 700hp.

Now the sonic numbers are very nice from the thrust sides all around, but there are core shift in non-thrust direction. Worst spots are only .090" in cyl 4 and 8. I tested the block myself with Dakota Ultrasonics PR-82 tester which I calibrated before the test. I took a lot of readings and nothing was left unnoticed.

The block is now in 4.04" size, and I was thinking the bore centerlines could be moved about .020" in non-thrust direction when it gets bored .040" bigger. That way those thin walls wouldnīt get much more thinner really, but the guestion is, are they too thin already? If it was a production block then that would be the case, but this is more rigid raceblock with high nickel casting so Iīm not quite sure. I will consider sleeves if itīs too risky wihout them.

Attached picture 7972383-x-blocksonic.JPG
Posted By: 1967dartgt

Re: X-block sonic test results - 12/27/13 05:20 AM

I would sleeve it and go 4.100 bore.
Posted By: 79410aspenrt

Re: X-block sonic test results - 12/27/13 06:09 AM

My x block is sleeved. 4.100 bore and 4.125 molnar crank. 4 bolt mains, half fill.

652 hp at 6800 rpm and 590 ft lbs at 4800 rpm.
Posted By: mopster

Re: X-block sonic test results - 12/27/13 10:20 AM

Would you sleeve #4 and 8 or all four from right side?
Posted By: Oyvind Mopar

Re: X-block sonic test results - 12/27/13 11:59 AM

You could bore the # 4 and 8 moving them so you bore .030 against the front and .010 against the rear (c/l moved .015"), it depends on how much you need to bore to clean the cylinders up. I do this all the time, moving the cylinders if there is significant core shift. As long as the rest of this block is so good that is what I would do, if you have to bore to 4.080! My
Posted By: Oyvind Mopar

Re: X-block sonic test results - 12/27/13 12:19 PM

Maybe I missed your point; is it strong enough already? I would say the block will be weakened with sleeves, but the sleeved cylinders will be fine. So, how thick do you want the sleeves? With the thin spots a proper sleeve will go through. A thin sleeve will weaken the old cylinder where it is thin so it can crack, then the whole culinder will be deformed. If you go thick: This means it will be a half wet - half dry sleeve, and coolant can get in between. Could be some issues there. When this happens to me I machine away the whole cylinder and add a thick sleeve, preferably with a small flange on top. A thick sleeve means appx 0.2" thick. This is less than your good cylinders, and the support from the remains is not worth much when they are not all around the circle.
I would say that sleeves can be added anytime, but the original block is at your hand now. And, for racing you will always have some maintenance dismantling, checking etc., so the workload would not matter too much if you need to redo it. Try it as it is! My
Posted By: mopster

Re: X-block sonic test results - 12/27/13 03:44 PM

Itīs just that if one cylinder wall fails it can take the whole shortblock with it and thereīs nothing to repair anymore.

Interesting info about sleeves, how everyone else are sleeving cylinders? How thick sleeve? Dry, wet, half wet?
Posted By: MR_P_BODY

Re: X-block sonic test results - 12/27/13 03:52 PM

Quote:

Itīs just that if one cylinder wall fails it can take the whole shortblock with it and thereīs nothing to repair anymore.

Interesting info about sleeves, how everyone else are sleeving cylinders? How thick sleeve? Dry, wet, half wet?



I had 1 block sleeved in 1 cyl... that was into water...
that same sleeve failed and I had it sleeved again...
since then its been fine... you have a few cyl on
the THIN side and your not even at your bore size
yet... I can see why the person is selling that block
but if you want to throw some money at it, it can
be saved
EDIT
On the off cutting the cyl... first put the cyl heads
on and mark the bores on the head and see if you can
move the chamber over some
Posted By: MoparBilly

Re: X-block sonic test results - 12/27/13 03:53 PM

Two things I don't do: Follow my Wife around when she's "out" with friends, and sonic check blocks! Some things in life you're just better off not knowing!

My 4 bolt X block has been running High 10's, low 11's since the 90's at 4.040, just bought a BPE kit, 4.125 crank and 4.070 bore. Want us to sonic check that for ya? No Thanks!

Attached picture 7973019-drag-week-2012-final-day-saturday-tulsa-7575.jpg
Posted By: Guitar Jones

Re: X-block sonic test results - 12/27/13 04:32 PM

Will it clean up at 4.060?
Posted By: viperblue72

Re: X-block sonic test results - 12/27/13 04:46 PM

moparbilly,
I bet that you are never going to get a colonoscopy either.
Posted By: Crizila

Re: X-block sonic test results - 12/27/13 04:54 PM

Quote:

Two things I don't do: Follow my Wife around when she's "out" with friends,

Bore it minimum to clean it up and run it.
Posted By: 79410aspenrt

Re: X-block sonic test results - 12/27/13 06:57 PM

mine has been sleeved for years, must be 10 for sure. they put in bigger sleeves so I could bore out more then 1 time. it was bored to 4.080 in 2005 and I took it to 4.100 this spring.

never any problems with the sleeves. it seen 8500 rpm for a lot of years.
Posted By: KOS

Re: X-block sonic test results - 12/27/13 11:16 PM

Quote:

I would sleeve it and go 4.100 bore.



i agree...... better ring selection also at that bore vs 4.080
Posted By: mopster

Re: X-block sonic test results - 12/28/13 12:25 AM

Quote:

Will it clean up at 4.060?


It doesnīt really matter if it will be bored another .020" or .040" because bore centers will be moved, and as little as possible will be cut from the thin sides. Theres plenty of meat in all the other walls, and also combustion chamber fitment is not a problem since the heads for this engine is still as cast and I can match them after the block is done. The thinnest spots will end up around .080" without sleeves.

The question is can it handle 700hp and 13:1 compression that way or does it have to be sleeved? And if so, how many sleeves and how thick? Does it matter if part of the cylinder goes through into water? Taking out the whole cylinder sounds a bit extreme to me Not easy guesions but all input is appreciated.
Posted By: J_BODY

Re: X-block sonic test results - 12/28/13 04:41 AM

Quote:

Two things I don't do: Follow my Wife around when she's "out" with friends, and sonic check blocks! Some things in life you're just better off not knowing!

My 4 bolt X block has been running High 10's, low 11's since the 90's at 4.040, just bought a BPE kit, 4.125 crank and 4.070 bore. Want us to sonic check that for ya? No Thanks!



I had my new R3 block sonic checked..... it was GOLD!! ....but I'm not looking for "high 10's low 11's" either.. been there done that.

....but the Mirada RB block was never sonic checked, or filled and that poster child for scrap metal was dishing out 9.9 passes! would love to have that block checked!!
Posted By: mopster

Re: X-block sonic test results - 12/28/13 06:20 PM

Quote:

Does it matter if part of the cylinder goes through into water? Taking out the whole cylinder sounds a bit extreme to me Not easy guesions but all input is appreciated.


On the other hand, if a thick sleeve is installed, there is not much left of the original cylinder. It may be only one wall that still has enough meat to add strenght to the block.

Oyvind, has there been trouble with the blocks after removing a cylinder and replacing it with a thick sleeve. Have you done more than one from same side?
Posted By: DavidDean

Re: X-block sonic test results - 12/28/13 06:31 PM

I recently built an X block project. I found core shift front to back (non thrust) I had the passenger cylinders off set bored about .050 to try to compensate for the core shift. I ended up with thrust wall thickness over .250 non thrust (between the cylinders ended up about .100).The finished bore size is 4.125.Before boring I did an extra tall fill (barely room for coolant). I used moroso offset dowels to try to center the heads the best I could.The engine was challenging to make everthing fit right. I had problems with radial valve clearance. push rod clearance in the head and piston to rod clearance. I finally made everthing fit right after lots of head scratching and cussing. I'm still using this motor, it is 454" w/ a BPE 4.250 crank. IMM indy 360-1 heads. It made about 780 hp on sunset's dyno. Its been 5.66 @ 120 1/8 shifting at 6500.If I had it to do again I would have made a number of changes(maybe smaller bore less offset bore). I've started another project w/a tall r block and W-8 heads because I'm afraid this motor may have a "short fuse" even though it has some good parts.My fear comes from the X block.

Attached picture 7974406-bracketnationals.jpg
Posted By: mopster

Re: X-block sonic test results - 12/30/13 12:43 AM

Quote:

mine has been sleeved for years, must be 10 for sure. they put in bigger sleeves so I could bore out more then 1 time. it was bored to 4.080 in 2005 and I took it to 4.100 this spring.

never any problems with the sleeves. it seen 8500 rpm for a lot of years.


So you have thick sleeves, how many? Are they in the same side?
Posted By: 79410aspenrt

Re: X-block sonic test results - 12/30/13 01:07 AM

I have 3 sleeves. 2 on drivers side and 1 on passenger side.

I was advised to put thicker sleeves in for future rebuilds.

don't know if it matters but at 4.080'' it seen 8500 rpm for years.

now it's at 4.100'' and sees 7100 rpm in my 3800 lbs R/T.

13.1 comp with iron heads.
Posted By: Oyvind Mopar

Re: X-block sonic test results - 12/30/13 07:54 PM

Quote:

Quote:

Does it matter if part of the cylinder goes through into water? Taking out the whole cylinder sounds a bit extreme to me Not easy guesions but all input is appreciated.


On the other hand, if a thick sleeve is installed, there is not much left of the original cylinder. It may be only one wall that still has enough meat to add strenght to the block.

Oyvind, has there been trouble with the blocks after removing a cylinder and replacing it with a thick sleeve. Have you done more than one from same side?


No, not yet. But I did some special tricks to avoid water leaks, as there is not much support especially in the bottom. Made a small portion with extra clearance to allow RTV against the oiling side, same with the chamfer to allow for RTV. With a flange sleeve I made the top surface flat, but with a sleeve seated in the bottom I added a few hundreds of a mm overheight to allow the sleeve to compress when heads are torqued down. I have done these sleeving jobs for repair only, so one per block only. Be aware that when sleeving the neighbour cylinders distort, so do the final boring after the sleeve(s) is installed. My
Posted By: GTSDave

Re: X-block sonic test results - 01/02/14 07:20 AM

DavidDean,

Didn't want to hijack the thread, but I love that pic.

What belly pan are you using? Can't quite tell from the pic you posted if it is an off the shelf item or a custom one, but it looks great. First pic of an A body I have seen with a pan. Was thinking about going with one for my Cuda, but I haven't found much info on them, and kinda figured it had to be something custom.

-Dave
Posted By: DavidDean

Re: X-block sonic test results - 01/02/14 05:48 PM

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