Flat Plane Crank LS1

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 -->
 
I think its a great idea and look forward to the build if that is what you decide to do. I was looking at getting a Ferrari V8 for the SLC for the reasons you talk about but after thinking through the initial cost and not knowing how easy they are to work on, etc. I figure the Chevy small block route is best.
 

Keith

Moderator
I believe balancing the reciprocating assembly would be your biggest issue and you should be prepared to glue your teeth in if you succeed in this interesting project.
 
I know it's not an LS, but why don't you look into the Coyote if you are looking at a flat planed V8 yes, you'll have to get custome Crank and Cams. The DOHC valvetrain can easily go to 8500 or more. Granted you will be limited to about 4.5L or so if you de-stroke it, but that's about the same as a Ferrari F458.

However if you are going for just the sound check this out. Maybe find out how this guy did his 180's and what else he did, it's a set of 180's on a Vette, sounds pretty exotic to me

LG Motorsports C5R Drag Race Corvette - YouTube

CRAZY FAST CORVETTE AT THE TRACK - YouTube
 

JohnC

Missing a few cylinders
Lifetime Supporter
If you want a flat plane crank, and a high RPM screamer that sounds like a Ferrari, why don't you just buy a Ferrari V8 instead of trying to make some of these other motors something they're not? It sounds easy enough to get a flat plane crank built for a cross plane motor, but working out all the little issues that crop up during the development could be expensive.

You might be surprised at the pricing on a Ferrari V8 ala 348/355 vintage if you want to go longitudinal engine, or earlier and cheaper (308/328) for a transverse engine.

If you get linked into the Ferrari breakers and various classifieds, you might find a deal. Best to get the engine & tranny, of course.
 
A quick search on Ebay yealds two 360 motors and a 430 motor. The 430 motor and one of the 360 motors are each $30k with no transaxle. The other 360 motor is $30k for motor and transaxle. I dont think any of them come with ECU's so thats going to be expensive. It would be fun to put one of these motors in an SLC, and its something I considered for a bit, but I think it will easily double the cost of the build. Also, the 360 and 430 motors look pretty tall, I wonder if they would even fit.
 
hey Troy, I agree with you as well, it would be good to get a different sound from the LS, people will never quite know how you did and it will be different so all for support! LS engines are still cheap to maintain, so I don't think you need to go get a ferrari engine.

There are flat plance cranks being tested right now by Lingenfelter. the cars are brutally fast in a straight line, so you may give them a call and see what it would take to buy a rotating assembly. Also, at those high RPM levels, you'll need some very light valvetrain.

Lingenfelter 358 CID LSx Flat Plane Crank Engine - YouTube
 
The Ferrari engines are just way to much money. The Coyota engine has DOHC, which would be really nice and something to think about. I looked into the 5.7L Toyota engine with DOHC. The issue is I still have to do crank, rods and maybe pistons. Then I have 4 cams to get made. I called webcams and they want $4000 to do it. So that is $3000 more and still have to get better valve springs, retainers, ect to reve high. So then I have 32 custom valve springs and other things to get. It could be nicer, but much much more money in the end I think. I just spent some time reading and reving an LS1 to 8000-8500 is not all that hard with the right vavle springs and other items. Also, LS1 parts are really cheap compared to other items.

I see people saying the engine will vibrate more, but see that most F cars are not balanced that way until you get to the 430. So a destroked LS to 4.7L might not be that bad at all. I would use some rubber or poly engine mounts to help and I think that might help a lot compared to a solid mounted engine to the chassis. Also, I have not seen anyone do an LS1 flat plane crank that says it has more vibration, just people on the internet saying it will have a little more so who knows how much it will really have until done. They say it is more at lower rpm and idle so I can bump up the idle anyway with the cams so we can see.

The more I think about it the more I want to do this. I will call lingerfelter and see what they say also, but I am 90% sure this is go at this point. The V6 TT might make more power, but still be a V6 TT in the end. The flat plane crank LS1 reving to 8500 and sounding nasty as hell would be something way different and make the driving experinece more fun for me.

Now, I just need to find an LS1 used complete with wiring harness and ecu. If anyone sees one that is good and pretty cheap let me know.

Troy
 

JohnC

Missing a few cylinders
Lifetime Supporter
A quick search on Ebay yealds two 360 motors and a 430 motor. The 430 motor and one of the 360 motors are each $30k with no transaxle. The other 360 motor is $30k for motor and transaxle. I dont think any of them come with ECU's so thats going to be expensive. It would be fun to put one of these motors in an SLC, and its something I considered for a bit, but I think it will easily double the cost of the build. Also, the 360 and 430 motors look pretty tall, I wonder if they would even fit.

Scott, the 360 and 430 are still relatively new models and are going to be expensive.

A quick search on Ferrari Chat's Classifieds brings up a 2.7 version F355 motor with ECU's for $16K. Seller represents it to be "like new".

There is even a 550 V12 on there for $10K, albeit in rough shape.

Breakers like Ferrparts, Eurospares, etc. will have stuff that the search engines may not find.
 
Now, I just need to find an LS1 used complete with wiring harness and ecu. If anyone sees one that is good and pretty cheap let me know.

Troy[/QUOTE]

Start with an LS3. Many internal improvements have been made over the LS1.

The short exhaust system in the SL-C with LS7 manifolds can make some awesome noise. The LS376 with a quick ramp rate ASA camshaft will give
a throaty rumble at idle and really sing at higher RPM's.

The LS3 engines are much better than the older LS1's for any mod's. I
happened to have a fresh LS1 and it was easily modded to around 430HP
(dyno) with simple head/camshaft work. Perfect for my street SL-C.
 
I've rewired a few of the LS1 411pcms to go into earlier generation camaro's and they are very easy. I say that to save you some money so that you don't buy a ripoff ebay complete package that is just stupid over priced.

For engine, I assume you want a aluminum block which is going to limit you to a l33, ls1, ls2, ls3. The best value in that bunch is the L33 (I have one in storage). the l33 is a 5.3 and they can take a ridiculous amount of turbo beating in stock form if you ever go that route.

if you don't want aluminum, then I would get a 2004+ 4.8L for about $550 (that's how much I paid for my last one). It currently has a ls6 cam/intake on it and should be good for about 330-350hp for less than 1k. It will rev/pull to 7000 easy (i upgraded the valve springs as well)
 
btw- which accessory drive works for the SLC? I assume the truck one is out since it protrudes more, so it's either going to be a CTS setup, corvette or fbody? the fbody accessories I paid around $400. plus the fbody oilpan $200 more.
 
I am thinking ls1,2 or 3. The newer I would think would cost more and since I have to upgrade almost all internals and not going for all Hp the ls1 might be best. But, do the newer ones have cyl heads that are way better?
 
I am thinking ls1,2 or 3. The newer I would think would cost more and since I have to upgrade almost all internals and not going for all Hp the ls1 might be best. But, do the newer ones have cyl heads that are way better?

the best motor in the bunch is really the l33 for the money. for $2500 or less including engine, I'm confident I can get the L33 to make just as much power as a stock $7000 ls3. The l33 makes more power than a ls1 and the heads are the same that were on a z06. l33 stock were 305-335 if i recall correctly, the ls1 was 305-315 stock. the key with the L33 is that it comes with 243/799 heads flow incredible. Guys are taking these heads off L33s, putting them on stock ls1s and with small cams 224/230 putting down 400rwhp. no small feat. My bolt on ls1 SS camaro only makes 335rwhp. If I swap on the l33 heads, I will pick up another 30hp easily.

The other thing the l33 has are stronger rods so it's a solid baseline.

I know a lot of this gets confusing, but it's pretty simple. You can take any engine and run it with the 411 pcm. The 411 is designed for the 24x reluctors but can also run the 58x cars with a $250 module from Lingenfelter. That basically means that the $100 PCM that you can buy on EBAY all day long will run ANY LS based engine. Hope that helps.
 

Ken Roberts

Supporter
btw- which accessory drive works for the SLC? I assume the truck one is out since it protrudes more, so it's either going to be a CTS setup, corvette or fbody? the fbody accessories I paid around $400. plus the fbody oilpan $200 more.

The Corvette accessory drive won't work due to the high mounted alternator location. F Body accessory drive sticks out too far.

The only two "factory" accessory drives that work are the CTS V and Pontiac G8 GXP.
 
Crash course in ls engine knowledge. I love it. L33. I will look at thae one if the heads are better. I will have new custom long con rods for the shorter stroke crank.
 
I just went on eBay and there is a 98 ls1 with harness, ecu and alt for $2000 and one state away. That seem good to be able to find it that quick and easy.
 
I just went on eBay and there is a 98 ls1 with harness, ecu and alt for $2000 and one state away. That seem good to be able to find it that quick and easy.

lkq salisbury (north carolina) has some l33 for 800-1000. not sure how far that is for you. car-part.com pick a 2005 silverado 1500 and choose option l33 for engine with your zip code.

edit: this is what you're looking for in the description , VIN B (8TH DIGIT, OPT L33)

2k for a 98 is too much imo. they have some undesirable options in 98 (perimeter bolt valve covers, and it's 14 years old now). You can get an engine for half that cost that is 7 years newer.
 
Back
Top