Here is the post I put on LS1tech, but would like your thoughts also.
Hello all. First post and I am going to try to make it a good one. I am building an SLC here soon and trying to decide on which engine to put in it.
I have done the searchs and found a few threads on the flat plane crank, but do not see anyone finishing them up. I have even seen somewhere someone had a crank all the way made up but bailed on the project later on.
I think I have gone crazy, but I hope in a good way, but I have been pondering this for a while. I really want an exotic sounding engine that is unique for the SLC. The V8 LS sounding engines are ok to me, just not an exotic scream. I want the scream and need the scream. I do not know why, but I have a sickness.
I am personally not interested in all out power. I find that now I have been tracking cars and racing for about 10 years I have seen myself go through the bell shaped curve of hp desire. At first I started out with an 85hp MR2 on the track and thought it was fun, but wanted more hp. Eventually got to 500rwhp and was not a great driver at the time and way too much car for me. Now I feel I am much better driver and do not need the high hp numbers and find it more fun to drive a car closer to the limit on all aspects of the track just as enjoyable as going 20-30mph more at the end of the straights. Finding the limits of the car and pushing yourself to do better at those limits is satisfying. Plus, my car will be a street car so the feeling I get from driving it each day is more than all out speed. The sound of the engine has a huge impact to me on the feel of the car of this type.
My plan for my engine was/is a Toyota V6, 3mz-fe and then twin turbo it later. Rev to about 8,000. To really ring it out and do it right it would be about $6000 for all the items and build up the motor. So not a bad way to get to 450-500rwhp. If I wanted 600-700rwhp it would be like $12K. Now I already have the engine, ecu, harness for the NA and about 230-250rwhp. So I think I might put that in at first as I have it and know it will work fine. Or just get a low HP LS1 used and start with that. This way I get use to the car and get it mainly sorted out. The fuel system is basically the same and oil coolers and such can be swapped back and forth as needed for either setup.
So after saying all that and seeing the LS1's can be had so cheap I am really considering doing a custom flat plane crank LS1. Get the crank custom, cam and con rods custom made. Upgrade the valve train to rev to 8000-8500. Now I just need to figure out what the right specs are.
Now I know the engine will vibrate more and that is ok if a little more so it will need to be de stroked.
Here is what I am thinking and the math I have done.
LS1 3.9 bore 3.622 stroke for 5.68L
F430 3.62 bore 3.19 stroke for 4.3L
F458 3.7 bore and 3.2 stroke for 4.5L
S2000 3.4 bore and 3.3 stroke for 4.0L (if V8)
3SGTE 3.39 bore 3.39 stroke for 4.0L (if V8)
3mz-fe 3.62 bore 3.4 stroke for 4.6L (if V8)
Carrera 3.86 bore 2.9 stroke for 4.4L (if V8)
HSV-010 3.6 bore 2.5 stroke for 3.3L, but they rev to like 11K and limited to 3.3L I believe
So after looking at these engines with the bore and stroke I am thinking a few things. The F430, 458, S2000 and 3sgte all hover around the 3.2-3.3 range and all can rev to about 8500-9000 without much of a problem. The engines that seem to rev higher have a shorter stroke and with the LS1 it is limited to the valve train to get it higher. I bring up the 3sgte because I built my old engine to rev to 10,000 and never have an issue, but it was dohc built so I do not expect that high. The 3mz-fe engine if I put in some stiffer valve springs 8500 is possible. 8,000-8500 should be reasonable I would think for the LS1 with upgraded valve train from what I have read.
So I am thinking if it is 3.9 bore and 3.2 stroke we would have 5.0L V8 and have a con rod ratio of about 2.05 and might be ok to rev high. I know 1L bike engines that rev to like 12000 or so have a 2.12 con rod ratio. Or 3.9 bore and 3.4 stroke for 5.3L and con rod ratio of 1.86. The other option range is 3.9 bore and 3.0 stroke for 4.7L and con rod ratio of 2.25. I just wonder which would be better and how much more vibrations would it be.
It could have about 400rwhp or more and maybe 450 crank, give or take. TQ would be a bit lower and hp higher since higher up on the curve, but that would be fine for me. The car should weight about 2300-2400lbs when done.
On cams looking up higher rev cams I see the 260-270 degrees and would need more specifics to learn just what I want there, but I used 272-280 and had peak power at 8500 with the 4cyl turbo. Nascar teams seem to have similar cam specs to rev to 8500. I might have a loopy idle, but I am not sure if it will be all that bad. I just upped my old 4cyl to about 1000-1100rpm idle and it was all good. I know I would have to do solid lifters, stronger dual or tripple valve springs and Ti retainers with all lightweight items.
Con rods, just order custom ones that are the length needed and try to get a nice light weight set. Maybe even Alum ones if I am ok with replacing them after like 15-20K miles. The lighter ones would be nice and alum is usually cheaper.
Pistons, some light weight forged pistons or just keep stock? Reving higher might need something specific there, but maybe not.
EMS- I am thinking the stock ECU might be able to handle it. I would just need to get a system to tune it a bit for higher revs. Just need to rewire the injectors and coils for the correct firing order and maybe splice some together. It not I could use an AEM 4 that will run a 4cyl and those are way less money than a 6-8-10 cyl versions.
Exhaust. 8-4-2-1 system or similar. So 4-2-1 on each side equal length to match it up and should sound amazing.
Intake. I might look into short individual throttle bodies or keep that stock and see how it works.
On the cost. Crank 2-3K, cam 1k, con rods 1-2K, valve train 1-2k or less (goto love LS items). So cheap side if I can use the stock con rods and pistons maybe 4-5K and higher end if all items are needed and EMS maybe 8K.
What are you thoughts on the project? Recomendations for a shop to make the crank, cam and con rods?
Thanks for the help,
Troy<!-- google_ad_section_end -->
Hello all. First post and I am going to try to make it a good one. I am building an SLC here soon and trying to decide on which engine to put in it.
I have done the searchs and found a few threads on the flat plane crank, but do not see anyone finishing them up. I have even seen somewhere someone had a crank all the way made up but bailed on the project later on.
I think I have gone crazy, but I hope in a good way, but I have been pondering this for a while. I really want an exotic sounding engine that is unique for the SLC. The V8 LS sounding engines are ok to me, just not an exotic scream. I want the scream and need the scream. I do not know why, but I have a sickness.
I am personally not interested in all out power. I find that now I have been tracking cars and racing for about 10 years I have seen myself go through the bell shaped curve of hp desire. At first I started out with an 85hp MR2 on the track and thought it was fun, but wanted more hp. Eventually got to 500rwhp and was not a great driver at the time and way too much car for me. Now I feel I am much better driver and do not need the high hp numbers and find it more fun to drive a car closer to the limit on all aspects of the track just as enjoyable as going 20-30mph more at the end of the straights. Finding the limits of the car and pushing yourself to do better at those limits is satisfying. Plus, my car will be a street car so the feeling I get from driving it each day is more than all out speed. The sound of the engine has a huge impact to me on the feel of the car of this type.
My plan for my engine was/is a Toyota V6, 3mz-fe and then twin turbo it later. Rev to about 8,000. To really ring it out and do it right it would be about $6000 for all the items and build up the motor. So not a bad way to get to 450-500rwhp. If I wanted 600-700rwhp it would be like $12K. Now I already have the engine, ecu, harness for the NA and about 230-250rwhp. So I think I might put that in at first as I have it and know it will work fine. Or just get a low HP LS1 used and start with that. This way I get use to the car and get it mainly sorted out. The fuel system is basically the same and oil coolers and such can be swapped back and forth as needed for either setup.
So after saying all that and seeing the LS1's can be had so cheap I am really considering doing a custom flat plane crank LS1. Get the crank custom, cam and con rods custom made. Upgrade the valve train to rev to 8000-8500. Now I just need to figure out what the right specs are.
Now I know the engine will vibrate more and that is ok if a little more so it will need to be de stroked.
Here is what I am thinking and the math I have done.
LS1 3.9 bore 3.622 stroke for 5.68L
F430 3.62 bore 3.19 stroke for 4.3L
F458 3.7 bore and 3.2 stroke for 4.5L
S2000 3.4 bore and 3.3 stroke for 4.0L (if V8)
3SGTE 3.39 bore 3.39 stroke for 4.0L (if V8)
3mz-fe 3.62 bore 3.4 stroke for 4.6L (if V8)
Carrera 3.86 bore 2.9 stroke for 4.4L (if V8)
HSV-010 3.6 bore 2.5 stroke for 3.3L, but they rev to like 11K and limited to 3.3L I believe
So after looking at these engines with the bore and stroke I am thinking a few things. The F430, 458, S2000 and 3sgte all hover around the 3.2-3.3 range and all can rev to about 8500-9000 without much of a problem. The engines that seem to rev higher have a shorter stroke and with the LS1 it is limited to the valve train to get it higher. I bring up the 3sgte because I built my old engine to rev to 10,000 and never have an issue, but it was dohc built so I do not expect that high. The 3mz-fe engine if I put in some stiffer valve springs 8500 is possible. 8,000-8500 should be reasonable I would think for the LS1 with upgraded valve train from what I have read.
So I am thinking if it is 3.9 bore and 3.2 stroke we would have 5.0L V8 and have a con rod ratio of about 2.05 and might be ok to rev high. I know 1L bike engines that rev to like 12000 or so have a 2.12 con rod ratio. Or 3.9 bore and 3.4 stroke for 5.3L and con rod ratio of 1.86. The other option range is 3.9 bore and 3.0 stroke for 4.7L and con rod ratio of 2.25. I just wonder which would be better and how much more vibrations would it be.
It could have about 400rwhp or more and maybe 450 crank, give or take. TQ would be a bit lower and hp higher since higher up on the curve, but that would be fine for me. The car should weight about 2300-2400lbs when done.
On cams looking up higher rev cams I see the 260-270 degrees and would need more specifics to learn just what I want there, but I used 272-280 and had peak power at 8500 with the 4cyl turbo. Nascar teams seem to have similar cam specs to rev to 8500. I might have a loopy idle, but I am not sure if it will be all that bad. I just upped my old 4cyl to about 1000-1100rpm idle and it was all good. I know I would have to do solid lifters, stronger dual or tripple valve springs and Ti retainers with all lightweight items.
Con rods, just order custom ones that are the length needed and try to get a nice light weight set. Maybe even Alum ones if I am ok with replacing them after like 15-20K miles. The lighter ones would be nice and alum is usually cheaper.
Pistons, some light weight forged pistons or just keep stock? Reving higher might need something specific there, but maybe not.
EMS- I am thinking the stock ECU might be able to handle it. I would just need to get a system to tune it a bit for higher revs. Just need to rewire the injectors and coils for the correct firing order and maybe splice some together. It not I could use an AEM 4 that will run a 4cyl and those are way less money than a 6-8-10 cyl versions.
Exhaust. 8-4-2-1 system or similar. So 4-2-1 on each side equal length to match it up and should sound amazing.
Intake. I might look into short individual throttle bodies or keep that stock and see how it works.
On the cost. Crank 2-3K, cam 1k, con rods 1-2K, valve train 1-2k or less (goto love LS items). So cheap side if I can use the stock con rods and pistons maybe 4-5K and higher end if all items are needed and EMS maybe 8K.
What are you thoughts on the project? Recomendations for a shop to make the crank, cam and con rods?
Thanks for the help,
Troy<!-- google_ad_section_end -->