4.25 stroke in LSX block
#1
4.25 stroke in LSX block
I know they say that this block will handle a 4.25 stroke but with a 5.5 inch cyl. length and a real short piston with say a 1.115 compression height for a 6 inch rod there is way to much skirt sticking out the bottom of the cyl. Even with a 4 inch stroke the tip of the skirt must poke out. Just because the rods will clear the sides of the block doesn't mean a 4.25 will work and last. Are people putting longer sleeves in these lsx blocks to use these strokes. I guess thats what I'm going to do. Are there any plans for a tall deck lsx? I know they're heavy but not everyone can afford the Warhawk or a RHS plus I like the bigger bore size.
#2
I know they say that this block will handle a 4.25 stroke but with a 5.5 inch cyl. length and a real short piston with say a 1.115 compression height for a 6 inch rod there is way to much skirt sticking out the bottom of the cyl. Even with a 4 inch stroke the tip of the skirt must poke out. Just because the rods will clear the sides of the block doesn't mean a 4.25 will work and last. Are people putting longer sleeves in these lsx blocks to use these strokes. I guess thats what I'm going to do. Are there any plans for a tall deck lsx? I know they're heavy but not everyone can afford the Warhawk or a RHS plus I like the bigger bore size.
There was talk of a tall deck LSXiron. But the regular LSX iron block...I think most would say not to do a 4.250 stroke.
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#4
Are you saying the LSX block can take sleeves? That would be something new to see.
Isn't the iron that the sleeves are made from harder/stronger than that of the block? So it would only make sense to sleeve it if possible, then you would have a harder cylinder with the sleeve support of the iron block.....unlike the less sturdy aluminum block.
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Last edited by LS6427; 10-21-2009 at 01:33 AM.
#5
Anything can take a sleeve. It may be a whole 'nuther ballgame trying to completely resleeve to try to get cylinder length, which is what I think you're talking about. I'm sure these are made from similar iron to the earlier generation of Bowtie blocks. Ask your machinist - there's a world of difference in the hardness of this cast iron and a production piece.
#6
I can tell you a Wiseco piston even with a 1.2mm ring package needs at least a 5.690 sleeve length to work with a 4.250 stroke crank at this compression height and our thick lands. Most blocks don't have this length. To my knowledge, we've got the heighest standard break point on standard stocking pistons of any company. There are some piston companies that are reluctant to pass this info on to forum viewers for a multitude of reasons, so they should post if this is the case. We do have other higher break points that can be used, but we do those on a case by case basis as it's a touchy engineering situation. Thinner lands can be used as well, but other issues can develop. Reluctor to pin boss clearance can become an issue and even a strutted piston may require minor clearancing.
#7
My sleeves are on the way and I'll start boring tomorrow. Should be an easy fix to lenghten these cylinders enough so none of the skirt will protrude out the bottom. I turned down the counterweights on the crank and added 15 slugs of heavy metal and rough balanced the crank. This gives me plenty of extra room and less that will have to be removed from the sleeves.
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#8
Sleeving the LSX
The Darton LS7 dry liner (5.800" long) should work in the LSX block. It may not match the crankcase cut out perfectly in the bottom but it doesn't match perfectly on the C5R block either I use these sleeves to repair those blocks.
I have installed large bore MID sleeves in the LQ9 blocks, by the way.
Yes the Darton sleeve material is both harder and stronger than the parent gray iron of the block. That is but one reason why Nascar and Pro Stock runners are sleeving their blocks.
It would cost somewhat more to dry sleeve the LSX than an aluminum block since iron does not machine as easily as aluminum plus one has to wrestle with the weight of the LSX getting it on and off the CNC. I rethread the head bolt holes for half inch studs on these things so I'm very familiar with the weight issue.
Steve
I have installed large bore MID sleeves in the LQ9 blocks, by the way.
Yes the Darton sleeve material is both harder and stronger than the parent gray iron of the block. That is but one reason why Nascar and Pro Stock runners are sleeving their blocks.
It would cost somewhat more to dry sleeve the LSX than an aluminum block since iron does not machine as easily as aluminum plus one has to wrestle with the weight of the LSX getting it on and off the CNC. I rethread the head bolt holes for half inch studs on these things so I'm very familiar with the weight issue.
Steve
an LSX iron block??? I asked this long ago and got a whole bunch of "no ways".
Are you saying the LSX block can take sleeves? That would be something new to see.
Isn't the iron that the sleeves are made from harder/stronger than that of the block? So it would only make sense to sleeve it if possible, then you would have a harder cylinder with the sleeve support of the iron block.....unlike the less sturdy aluminum block.
.
Are you saying the LSX block can take sleeves? That would be something new to see.
Isn't the iron that the sleeves are made from harder/stronger than that of the block? So it would only make sense to sleeve it if possible, then you would have a harder cylinder with the sleeve support of the iron block.....unlike the less sturdy aluminum block.
.
__________________
Steve Demirjian
Race Engine Development
Oceanside, Ca.
760-630-0450
web: www.raceenginedevelopment.com/
e-mail: race-engine-development@***.net
Steve Demirjian
Race Engine Development
Oceanside, Ca.
760-630-0450
web: www.raceenginedevelopment.com/
e-mail: race-engine-development@***.net
#10
The Darton LS7 dry liner (5.800" long) should work in the LSX block. It may not match the crankcase cut out perfectly in the bottom but it doesn't match perfectly on the C5R block either I use these sleeves to repair those blocks.
I have installed large bore MID sleeves in the LQ9 blocks, by the way.
Yes the Darton sleeve material is both harder and stronger than the parent gray iron of the block. That is but one reason why Nascar and Pro Stock runners are sleeving their blocks.
It would cost somewhat more to dry sleeve the LSX than an aluminum block since iron does not machine as easily as aluminum plus one has to wrestle with the weight of the LSX getting it on and off the CNC. I rethread the head bolt holes for half inch studs on these things so I'm very familiar with the weight issue.
Steve
I have installed large bore MID sleeves in the LQ9 blocks, by the way.
Yes the Darton sleeve material is both harder and stronger than the parent gray iron of the block. That is but one reason why Nascar and Pro Stock runners are sleeving their blocks.
It would cost somewhat more to dry sleeve the LSX than an aluminum block since iron does not machine as easily as aluminum plus one has to wrestle with the weight of the LSX getting it on and off the CNC. I rethread the head bolt holes for half inch studs on these things so I'm very familiar with the weight issue.
Steve
For an N/A set-up.....what max bore could you safely do if you resleeved it? Any more than just what the LSX iron block can do now?
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Last edited by LS6427; 10-21-2009 at 07:31 PM.
#11
To me, if your building something with all the best pieces and want everything right, you can't have any amount of the skirts sticking out the bottom so the thin wall liners eliminate that problem and still allows me to put a 4.200 bore with the long stroke and it will last and stay that way. Plus with the right liners you can run real narrow backcut rings and make more power than the conventional bore and ring package.
#12
To me, if your building something with all the best pieces and want everything right, you can't have any amount of the skirts sticking out the bottom so the thin wall liners eliminate that problem and still allows me to put a 4.200 bore with the long stroke and it will last and stay that way. Plus with the right liners you can run real narrow backcut rings and make more power than the conventional bore and ring package.
So, is the longest sleeve available the Darton 5.8" long one? And 4.125" stroke is all thats recommended for it, right?
What's its max safe bore for 100% N/A?
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#13
The sleeves I have coming are very long 6.350 because I'm gonna bottom it out all the way down to main bulkhead instaed of putting a register on the top of the sleeve. I use pvc pipe as a dummy sleeve to fit and clearance everything then just transfer the shape to my long sleeves and let the cnc shape the bottom of the sleeve before installing it. Much faster and easier. Once the sleeve is pressed in with .001 press fit and sleeve retainer, I trim the top and bore right in the cnc then tru the decks before putting the deck plates on and hot honing it. As far as max bore goes, it's not anything with the cylinder bores or wall thickness that stops me from using the 4.25 sizes it' keeping the head gaskets sealed between the bores because of the bore spacing. It doesn't leave much material.between them. If it was a spread bore like the new cup stuff (RO7) then I wouldn't even worry about it. I did a 4.25 bore on a pro stock truck engine with the stock bore spacing without any problems but they got rebuilt all the time.
#14
The sleeves I have coming are very long 6.350 because I'm gonna bottom it out all the way down to main bulkhead instaed of putting a register on the top of the sleeve. I use pvc pipe as a dummy sleeve to fit and clearance everything then just transfer the shape to my long sleeves and let the cnc shape the bottom of the sleeve before installing it. Much faster and easier. Once the sleeve is pressed in with .001 press fit and sleeve retainer, I trim the top and bore right in the cnc then tru the decks before putting the deck plates on and hot honing it. As far as max bore goes, it's not anything with the cylinder bores or wall thickness that stops me from using the 4.25 sizes it' keeping the head gaskets sealed between the bores because of the bore spacing. It doesn't leave much material.between them. If it was a spread bore like the new cup stuff (RO7) then I wouldn't even worry about it. I did a 4.25 bore on a pro stock truck engine with the stock bore spacing without any problems but they got rebuilt all the time.
4.250 stroke being the concern? I know the 4.185 bore is fine.
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#15
Interesting thoughts are developing......
What about a ERL type super deck on a LSX block ? This could be the answer to high power big cube race engines,and a aluminum deck could help to disipate heat. ( just floating ideas)
What would the max cubic inches be for a resleaved LSX block...?
What about a ERL type super deck on a LSX block ? This could be the answer to high power big cube race engines,and a aluminum deck could help to disipate heat. ( just floating ideas)
What would the max cubic inches be for a resleaved LSX block...?
#16
Interesting thoughts are developing......
What about a ERL type super deck on a LSX block ? This could be the answer to high power big cube race engines,and a aluminum deck could help to disipate heat. ( just floating ideas)
What would the max cubic inches be for a resleaved LSX block...?
What about a ERL type super deck on a LSX block ? This could be the answer to high power big cube race engines,and a aluminum deck could help to disipate heat. ( just floating ideas)
What would the max cubic inches be for a resleaved LSX block...?
.
#17
I've put deck spacers on iron blocks before just to be able to get a longer rod in it for better rod ratio, but I used meehanite for the spacer to keep the expansion rate the same. It had an extra set of locating dowels including the original dowels to locate the spacer then I bored through the spacer right down into the bores and pressed in the liners just like this lsx block except those sleeves had a register on the top. I didn't want a different material around the top of the liners where they need to be perfect. I'm going to try this on a 6.0 truck block.
#18
half inch head studs
The half inch head studs are not in the ARP catalog. You need to call them and they will put together a half inch stud kit for you.
I have not yet installed larger main studs on these blocks. You would need to either eliminate the locating dowels or install larger ones to get a half inch fastener to pass through. ARP should have half inch studs for another application that will work at least for the inner fasteners. You may have a problem with the outer fasteners for windage tray mounting.
Steve
I have not yet installed larger main studs on these blocks. You would need to either eliminate the locating dowels or install larger ones to get a half inch fastener to pass through. ARP should have half inch studs for another application that will work at least for the inner fasteners. You may have a problem with the outer fasteners for windage tray mounting.
Steve
__________________
Steve Demirjian
Race Engine Development
Oceanside, Ca.
760-630-0450
web: www.raceenginedevelopment.com/
e-mail: race-engine-development@***.net
Steve Demirjian
Race Engine Development
Oceanside, Ca.
760-630-0450
web: www.raceenginedevelopment.com/
e-mail: race-engine-development@***.net
#19
We already did this like 4 years ago with Steve at RED on a 6.0 block (447 CID engine) and it worked great as there wasn't an LSX block even out there at that time but of course it's very pricy and you could never hone anything much over even 6 inches correctly in any of these blocks.
You can sleeve anything of course but it needs to be able to have a crank and rods clear the sleeves and it needs to be hone-able. We were putting longer sleeves in almost 10 years ago from LA sleeve till I started using the DARTONs from Steve who is one of the very best out there and we still have yet to have an issue with any of his blocks.
You can sleeve anything of course but it needs to be able to have a crank and rods clear the sleeves and it needs to be hone-able. We were putting longer sleeves in almost 10 years ago from LA sleeve till I started using the DARTONs from Steve who is one of the very best out there and we still have yet to have an issue with any of his blocks.