Can't figure out steering rack solution on odd swap...
#22
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When I relocated the rack on my 1st gen LS1 Swap I had to lower the rack to clear the balencer, This is the solution I used. Some other guys like to remove the cast steering arm and bolt on one that reloctes the tie rod mount.
#25
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Just look at the overall length of a subaru engine. It's like 16inches long. You would hang the LS1 like 10 inches further. Even if you could fit it, it would destroy the handling of the car. Look where the axles are on a Subaru.
#26
Staging Lane
Thread Starter
To beat a dead horse, I realize what it will do to weight distribution, and I have driven a Legacy GT with comparable weight distribution, and I do not see front-to-back length as a problem that cannot be solved with relative ease. I have already addressed the problem of engine length and front height of the engine profile in my thread about a low profile front pulley, and the someone did it on a RS4 LS1 swap, showing that it can be done nicely with the accessories low and not sticking out so damn far.
The real problem is the relationship between the 1) trans/engine assembly height in car as stock is relatively high up, 2) steering rack, and 3) front axles.
The real problem is the relationship between the 1) trans/engine assembly height in car as stock is relatively high up, 2) steering rack, and 3) front axles.
#27
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I understand you're looking for a solution here - but if you don't find a suitable solution with the parts you have (which may or may not exist) then the only rational thing to do would be to change one of the parts that don't fit.
As much as I really like the LS platform, are there any other engine platforms that would get you closer to where you need to be from a packaging perspective while still giving you larger displacement for better streetability with a turbo setup? I think you would accomplish that using a shorter engine - probably a more compact V6. Have you looked into the V6 from the new-generation Camaros or Mustangs? They might be a little shorter, and let you keep the Subaru drivetrain where it is, making your swap SO much easier. Also, at about 4.0L, they'll give you the good low RPM torque while still having enough breath to push a larger turbo. If you could recover half of that 4" back, you might completely eliminate your steering problem.
If you're hell bent on the LS swap, here is an idea: Run a Trailblazer pan. Keep your rack where it is in the Subaru trans. Run steeply angled tie rods from the end on the rack to your knuckles. Overbuild them - use pipe or wide flat bar. Then, pass a solid bar (or a piece of pipe) through the lateral hole in the Trailblazer pan, connecting each end of the bar to each of the tie rod ends. This would effectively link together the two wheels. What way, each wheel will gain some stability from the other. This would be especially helpful when one wheel was under a lot of strain and the other was not (eg: going into a corner, the outside wheel is working hard and the inside one is not.) It's sort of an off-the-wall idea that might not solve all your problems, but it might be a jumping off point to something that does.
As much as I really like the LS platform, are there any other engine platforms that would get you closer to where you need to be from a packaging perspective while still giving you larger displacement for better streetability with a turbo setup? I think you would accomplish that using a shorter engine - probably a more compact V6. Have you looked into the V6 from the new-generation Camaros or Mustangs? They might be a little shorter, and let you keep the Subaru drivetrain where it is, making your swap SO much easier. Also, at about 4.0L, they'll give you the good low RPM torque while still having enough breath to push a larger turbo. If you could recover half of that 4" back, you might completely eliminate your steering problem.
If you're hell bent on the LS swap, here is an idea: Run a Trailblazer pan. Keep your rack where it is in the Subaru trans. Run steeply angled tie rods from the end on the rack to your knuckles. Overbuild them - use pipe or wide flat bar. Then, pass a solid bar (or a piece of pipe) through the lateral hole in the Trailblazer pan, connecting each end of the bar to each of the tie rod ends. This would effectively link together the two wheels. What way, each wheel will gain some stability from the other. This would be especially helpful when one wheel was under a lot of strain and the other was not (eg: going into a corner, the outside wheel is working hard and the inside one is not.) It's sort of an off-the-wall idea that might not solve all your problems, but it might be a jumping off point to something that does.
#28
Staging Lane
Thread Starter
Originally I was all about the 3800 engine, but the LSx is sooo much more streetable, while weighing almost the same. The new V6 is only a little lighter, but probably a lot weaker than its iron counterpart.
I had a similar idea to yours with the rack tie rod support bar, and one engineer so far has told me it is a terrible idea. I admit I have a lot to learn, and I intend to do so over time. There is some nice suspension geometry software available for free or cheap, and that will probably do a lot to help me see what changes will have what outcome. I've added 1/2 degree caster and lowered the front more than an inch (easy to change height) so it's already out of wack and may benefit from a ground-up analysis anyways since I'll already be in there.
I had a similar idea to yours with the rack tie rod support bar, and one engineer so far has told me it is a terrible idea. I admit I have a lot to learn, and I intend to do so over time. There is some nice suspension geometry software available for free or cheap, and that will probably do a lot to help me see what changes will have what outcome. I've added 1/2 degree caster and lowered the front more than an inch (easy to change height) so it's already out of wack and may benefit from a ground-up analysis anyways since I'll already be in there.
#34
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But the parts are a TON cheaper for ls stuff! Cheapest intake manifold (other than chinese) on a Subaru is around $1000 or more. The EJ30 or EJ36 would have to be custom as there is no manifold made for them. I can get pistons for a LS motor (8 of em) for about $100 less than comparable ones for a Subaru (4 of them). The 6 cylinder again would have to be custom. I can get 8 80 lb injectors for cheaper than 4 80 lb Subaru injectors and that will take me much further in hp....it's just cheaper in the domestic world.
#35
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I was suggesting a different engine because it would be shorter, not lighter. With that being said, I don't know how much shorter the other V6 engines are, but it would probably be worth looking into.
I have driven a couple of the new V6 and V8 Camaros and I think they're both equally streetable... plenty of low-end torque for everyday driving. (Under normal driving conditions, I don't think I could tell them apart except for the sound.) I'd be very surprised if the 6-cylinder engine was not capable of 600 streetable bhp. Afterall, it has some good things going for it, including an aluminum block, forged steel crank, DOHC, 11.3 CR, 300+ hp on regular gas, and a 7,000 RPM factory redline. It also has technology more advanced than the LS platform, such as direct injection and knock sensors for each individual cylinder. That sounds like a good starting point.
http://media.gm.com/content/media/us..._camaro_engine
As for the high HP durability of these engines, I haven't seen much of anything on them, good or bad. Maybe they're too new. But the 7,000 RPM redline is probably going to challenge the integrity of the engine more than adding a turbo, and is itself, a testament to the strength of the bottom end components and everything that supports them.
This is just one example. Other manufactures (Ford, Toyota, etc) probably have equally advanced engines around this size.
I appreciate the creativity of your project - I think you will have a great finished product when you're done! But sometimes trying to put a square plug into a round hole can be really tough. In fact, sometimes there is no satisfactory solution... not because you can't think of it or can't afford it, but because it simply does not exist with your chosen parts. At that point, it might be worth swapping your "square peg" for a "slightly rounder" peg to better fit your round hole!
Best of luck, and make sure you keep us posted on your project!! Post pics!!
I have driven a couple of the new V6 and V8 Camaros and I think they're both equally streetable... plenty of low-end torque for everyday driving. (Under normal driving conditions, I don't think I could tell them apart except for the sound.) I'd be very surprised if the 6-cylinder engine was not capable of 600 streetable bhp. Afterall, it has some good things going for it, including an aluminum block, forged steel crank, DOHC, 11.3 CR, 300+ hp on regular gas, and a 7,000 RPM factory redline. It also has technology more advanced than the LS platform, such as direct injection and knock sensors for each individual cylinder. That sounds like a good starting point.
http://media.gm.com/content/media/us..._camaro_engine
As for the high HP durability of these engines, I haven't seen much of anything on them, good or bad. Maybe they're too new. But the 7,000 RPM redline is probably going to challenge the integrity of the engine more than adding a turbo, and is itself, a testament to the strength of the bottom end components and everything that supports them.
This is just one example. Other manufactures (Ford, Toyota, etc) probably have equally advanced engines around this size.
I appreciate the creativity of your project - I think you will have a great finished product when you're done! But sometimes trying to put a square plug into a round hole can be really tough. In fact, sometimes there is no satisfactory solution... not because you can't think of it or can't afford it, but because it simply does not exist with your chosen parts. At that point, it might be worth swapping your "square peg" for a "slightly rounder" peg to better fit your round hole!
Best of luck, and make sure you keep us posted on your project!! Post pics!!
#36
Staging Lane
Thread Starter
Yes but you don't have to order custom internals to put in a crappy soft black, and you don't have to buy $4000 custom engine management solutions. My buddy who swapped in the 3.8L GN engine did so for a very low cost, and reasonable fuss given it's a big V6. Motor plate, motor mounts, move several things around, setup engine management. A bit of a mess but not one tenth the hell of a 6-cylinder Subaru.
[QUOTE=FastKat;15540294]I was suggesting a different engine because it would be shorter, not lighter. With that being said, I don't know how much shorter the other V6 engines are, but it would probably be worth looking into.QUOTE]
Interesting information, something to consider. VVT is a very good thing as is that CR, LSx is only now getting into VVT, but I don't see it making up for the lack of a 5.7L V8.
#38
Staging Lane
Thread Starter
I can almost get to 600bhp with my current engine and E85, though below 4000rpms forget about it. 3.8L (as I have been told anyways) is still nothing like the street manners of a comparably powerful 5.7 or 6.0. Based on many of the Dyno plots I've seen, I tend to agree. There are turbo 350Zs and Turbo 370Zs running high compression and VVT, and even with that combination it's still a compromise. I'd rather cram the LSx in.
You are right, any way you go, you give up a lot. I figure the pain of fitting the LSx can (hopefully) be a one shot pain, followed by years of insane fun. The car is otherwise great. Wagon for space. Attracts zero attention. Handles nicely. Good diffs. Good brakes. Still mildly comfo and doesn't feel cheap inside. It's either this or I learn to like RWD (which would be an easy sell with the right RWD platform) or buy an R35 (which isn't going to happen for at least 5-7 years. This swap could happen next year... and I like reliable, simple engines that get good economy. Best part of the swap, if I get crazier one day, out with the 5eat (if a low limit is found) and in with the 6MT (STi, very very strong).
You are right, any way you go, you give up a lot. I figure the pain of fitting the LSx can (hopefully) be a one shot pain, followed by years of insane fun. The car is otherwise great. Wagon for space. Attracts zero attention. Handles nicely. Good diffs. Good brakes. Still mildly comfo and doesn't feel cheap inside. It's either this or I learn to like RWD (which would be an easy sell with the right RWD platform) or buy an R35 (which isn't going to happen for at least 5-7 years. This swap could happen next year... and I like reliable, simple engines that get good economy. Best part of the swap, if I get crazier one day, out with the 5eat (if a low limit is found) and in with the 6MT (STi, very very strong).
#39
Staging Lane
Thread Starter
Like this!!!! Sort of. The tie rods mount to a bar offset of the steering rack axis, but would slide with the rack. The bar to which the inner tie rod joints are bolted would be shaped to sink back in towards the rack and this dodging the trans bellhousing, tucking in under the GTO oil pan, done... After confirming steering linkage will still clear axles.
#40
The trans
Do you really think a Subi trans will be able to handle the tq of an ls engine. I am doing a 2.5 SOHC plus 5 speed into a 914 so I know a little bit about these transmissions. They might hold up to a turbo 4 but a stout 3.0 or 3.3 six turbo is a crap shoot. In my case its a 2000 pound go-cart but anything heavier (or with bigger tires) and that trans is toast and you need to start spending $$$ on aftermarket gears (that will be loud as hell on the street.) Just drop a Subi six in it with some boost and hope the trans can take it.