500 - 510ci LSX GM tall deck
02-09-2016, 04:49 AM
#21
Teching In
Thread Starter
Join Date: Feb 2016
Posts: 19
Likes: 0
Received 0 Likes
on
0 Posts
I simply stated that someone from GM parts stated that, and I wondered where he got that from. We are discussing what the max bore\stroke is on anLSX tall deck block. Next time maybe u should try reading the ENTIRE thread before trying to chime in, and act like u know what's going on.
02-09-2016, 05:41 PM
#22
I have helped a customer of mine design and put together a 488" LS engine with a 4.145" bore, 4.500" stroke and 6.35" Ultra I beam Callies rod utilizing a RHS tall deck aluminum block. If this engine is destined to be a very high RPM(high RPM for a 4.5" stroke is 7600-8000rpm) high HP engine then you're going to have issues fitting the appropriate camshaft due to cam to connecting rod issues as KCS mentioned.
Cam to connecting rod clearances will be an issue without a raised cam tunnel, but with the RHS block my customer used we had no issues fitting a 2.165" BCD camshaft with a 6.35" rod because the cam tunnel is raised .300"+ versus stock. Dart and RHS both offer blocks like this in tall deck arrangements. If you stick with a LSX tall deck block, you will have to go with a 1.948" BCD which is a BBC BCD(50mm). This will allow whoever specs and grinds your cam enough room to fit the appropriate camshaft in your engine.
If this is not a high RPM drag race engine, then you probably won't have issues with a 2.165" BCD as long as you use a 1.8 ratio rocker to get the lift needed to feed a large engine like this. Using a higher ratio rocker will allow the cam to be ground with less lobe lift and thus have more cam to connecting rod clearance while still attaining the necessary valve lift.
I kept lobe lift at .472" on my customer's engine and had him utilize a 1.8 ratio rocker arm to provide some added lift that I felt was needed without adding more lobe lift. I likely could of had the cam ground with more lobe lift, but I didn't want my customer to end up with a $700 door stop and need to have a new camshaft ground on my dime.
I believe that SAM built a 500" tall deck engine with a ERL tall deck block for Judson's wife. It had LS7 heads and it went into the 9's on pump gas at a very respectable weight. IIRC it weighed roughly 3500#.
Cam to connecting rod clearances will be an issue without a raised cam tunnel, but with the RHS block my customer used we had no issues fitting a 2.165" BCD camshaft with a 6.35" rod because the cam tunnel is raised .300"+ versus stock. Dart and RHS both offer blocks like this in tall deck arrangements. If you stick with a LSX tall deck block, you will have to go with a 1.948" BCD which is a BBC BCD(50mm). This will allow whoever specs and grinds your cam enough room to fit the appropriate camshaft in your engine.
If this is not a high RPM drag race engine, then you probably won't have issues with a 2.165" BCD as long as you use a 1.8 ratio rocker to get the lift needed to feed a large engine like this. Using a higher ratio rocker will allow the cam to be ground with less lobe lift and thus have more cam to connecting rod clearance while still attaining the necessary valve lift.
I kept lobe lift at .472" on my customer's engine and had him utilize a 1.8 ratio rocker arm to provide some added lift that I felt was needed without adding more lobe lift. I likely could of had the cam ground with more lobe lift, but I didn't want my customer to end up with a $700 door stop and need to have a new camshaft ground on my dime.
I believe that SAM built a 500" tall deck engine with a ERL tall deck block for Judson's wife. It had LS7 heads and it went into the 9's on pump gas at a very respectable weight. IIRC it weighed roughly 3500#.
The following users liked this post:
anotherTodd (10-31-2020)
02-09-2016, 06:21 PM
#23
Teching In
Thread Starter
Join Date: Feb 2016
Posts: 19
Likes: 0
Received 0 Likes
on
0 Posts
Thank you for your helpful tips. I appreciate the information. It will not be for all out drag. Just looking to do somethin with a little different combo- nation than what people are already building. Besides raised cam tunnel, how different it the lsx in regards to the RHS block, besides the super obvio7s. I think u can go as high as 4.6 stroke in those. I'm wondering if\how much grinding I'm going to have to do on bottoms of cylinders etc'. Once again, I appreciate your information, it goes a long way. You can never know enough so thank you.
02-09-2016, 10:13 PM
#24
I believe the RHS block can be taken out further in terms of bore diameter than the LSX block which I believe KCS mentioned before.
Aside from a raised cam tunnel on the RHS, I don't believe their is much difference between the two blocks physically.
Aside from a raised cam tunnel on the RHS, I don't believe their is much difference between the two blocks physically.
The following users liked this post:
anotherTodd (10-31-2020)
02-10-2016, 04:25 AM
#26
Teching In
Thread Starter
Join Date: Feb 2016
Posts: 19
Likes: 0
Received 0 Likes
on
0 Posts
Yes as I said before, we are discussing MAXIMUM bore[on an lsx] as stated before. If u would have read the ENTIRE thread, u would have clearly realized we are far beyond this point by now. We know what 4.4" - 4.25 is but thanks for your grade school math anyway. I'm not here to argue with someone who is obviously illiterate. Some people, I think just come to these threads to argue, bcuz they have nothing better in life to do. But, to the people here who are helpful and come here to share their expertise w\o trying to put other people down, Thank u. For every1 with actual 'good' information. Your expertise is much appreciated.
02-10-2016, 06:10 AM
#27
Here's a link to the first one back in ...06,07? Manufacturers back then thought we lost our mind (and probably had, Tall Deck LS? 500 ci ? LOL)
http://www.superchevy.com/how-to/eng...-engine-build/
Martin is correct in getting the cam clearance. Back then we used a BBC base circle (custom cam core) and a 2.0" rod journal, since Tall Deck and much less raised cam options were available.
If you need one of those billet 4.5" stroke cranks PM me.
There are several of those original 500's out there and 1 guy road races his and loves it with all the torque !
http://www.superchevy.com/how-to/eng...-engine-build/
Martin is correct in getting the cam clearance. Back then we used a BBC base circle (custom cam core) and a 2.0" rod journal, since Tall Deck and much less raised cam options were available.
If you need one of those billet 4.5" stroke cranks PM me.
There are several of those original 500's out there and 1 guy road races his and loves it with all the torque !
The following users liked this post:
anotherTodd (10-31-2020)
02-10-2016, 10:08 AM
#28
Thank you for your helpful tips. I appreciate the information. It will not be for all out drag. Just looking to do somethin with a little different combo- nation than what people are already building. Besides raised cam tunnel, how different it the lsx in regards to the RHS block, besides the super obvio7s. I think u can go as high as 4.6 stroke in those. I'm wondering if\how much grinding I'm going to have to do on bottoms of cylinders etc'. Once again, I appreciate your information, it goes a long way. You can never know enough so thank you.
The following users liked this post:
anotherTodd (10-31-2020)
02-10-2016, 10:51 AM
#29
Teching In
Thread Starter
Join Date: Feb 2016
Posts: 19
Likes: 0
Received 0 Likes
on
0 Posts
Carl\KcS- do u guys know any1 running a 4.5 stroke crank. I'd love to hear what they are running in terms of bore\compression etc'. I thought about going to RHS block but can't come to terms with spending 5k on it. If it was for all out drag, then I'd definetly go that route. Carl- what's approx' cost for the billet crank u were talking about?
02-10-2016, 06:54 PM
#30
A lot of talk about the bore size. With a stroke that long a tall deck block is the only way it could be possible and even then I don't know. You don't want that piston coming out too far out of the hole cause its gonna get the **** beat out if it on the way back up.
Now for the common sense in me…why is that cid even needed or desire? Frankly these engines runs so well that for most performance goals this much cid is not needed.
Now for the common sense in me…why is that cid even needed or desire? Frankly these engines runs so well that for most performance goals this much cid is not needed.
02-10-2016, 08:36 PM
#31
Teching In
Thread Starter
Join Date: Feb 2016
Posts: 19
Likes: 0
Received 0 Likes
on
0 Posts
Honestly 30thannv'; the real down right main reason isn't about Hp, torque, or really any1 certain reason. It's just about seeing exactly what can go into that lsx tall deck and work-and work well. No nitrous no boost just engine. I've heard so many stories and read so many articles about what people have built or why people think a 4.5 stroke is a bad idea[in lsx] etc' etc'. I'm ready to do my own 500ci build on a tall deck lsx with different rod combos, different cam specs etc' to find out what exactly can go into that lsx and run well. I wana get exact clearances on stroke, check pistons[regarding knock\'slap' etc']. Everyone has their own opinions which they are entitled to. I've heard of many guys running this longer stroke and bigger bore[I will most likely be doing a 4.2] in rhs, dart, lsx and it working well. Then ive heard so many people down talk guys or tell them its\they're dumb bcuz what they are trying to do and just be dicks for really no reason. I am just trying to get answers for myself and whoever wants to know! I thought that is what building a powerplant is all about is; trying to make parts work well together or raising the bar and trying different things out that other people are only speculating about. Without the guessing, or what people think will work or might work. I've read many things and heard many things and why people think it's a horrible idea and think it's dumb to even try to come close to anywhere near 500ci or use a 4.5 stroke bcuz of pistons rocking too much or rpms being so shitty etc'. I'm just ready to figure it all out myself and see how well everything holds up and so on with different combos. I like taking everyone's input and what they think, bcuz it goes a long way. You can never know enough when it comes to engine building. But yeah buddy that's pretty much the just of it man lol
02-10-2016, 10:23 PM
#32
http://awesomeengines.biz/506ci-lsx-...m-race-engine/
Not sure how reliable that information on power output is, but that's what they claim.
I personally wouldn't use a 4.600" stroke on a LSX block, but I guess if you're willing to sacrifice compression height and strength of the piston go ahead.
You can definitely do a 4.600" stroke on the RHS and Dart blocks due to the added sleeve length. I confirmed this with RHS a while back, and Dart has an even longer barrel length.
I did a lot of research on this subject when I helped my customer build his 488" engine. Mainly because he started out with a LSX tall deck block in the beginning, but then he switched to a RHS to gain the raised cam tunnel to fit the cam I wanted.
Thought about doing the 2.0" rod journal with a 50mm BBC journal like Carl mentioned and keeping the LSX block, but in the end the raised cam tunnel RHS block was the best option since the Dart blocks had just arrived on the scene at that point in time.
Carl\KcS- do u guys know any1 running a 4.5 stroke crank. I'd love to hear what they are running in terms of bore\compression etc'. I thought about going to RHS block but can't come to terms with spending 5k on it. If it was for all out drag, then I'd definetly go that route. Carl- what's approx' cost for the billet crank u were talking about?
Compression on his engine is 14.5:1 and he is using a 4.145" bore piston.
A lot of talk about the bore size. With a stroke that long a tall deck block is the only way it could be possible and even then I don't know. You don't want that piston coming out too far out of the hole cause its gonna get the **** beat out if it on the way back up.
Now for the common sense in me…why is that cid even needed or desire? Frankly these engines runs so well that for most performance goals this much cid is not needed.
Now for the common sense in me…why is that cid even needed or desire? Frankly these engines runs so well that for most performance goals this much cid is not needed.
Some people just want to be different. I can tell you this though, the 488" I helped my customer build will make INSANE average HP and torque. I fully expect it to make 1000 crank HP if not more. I know that 1000 crank HP can be made with less cubic inches and more RPM, but in the end it is still piston speed. Doesn't really matter if you turn more RPM with less stroke, or turn less RPM with more stroke. It's still the same CFM demand and still the same or very similar piston speeds.
