Turbo placement at the rear????

There's a company in Utah who has a new LT1 turbo kit that will be coming out in production soon. The only thing strange or unique about their setup is that the turbo itself is placed in the rear near the mufflers:confused:

Now I can see how that could be beneficial in a few aspects as far as installation, underhood temps, intake charge temps, etc....and apparently they have worked out any lag that you would assume would be part of the deal with turbo placement that far back.

Here's the thread in our local Fbody club: http://www.ufba.org/forum/index.php?board=16;action=display;threadid=3476

Any thoughts, opinions, etc....

sized correctly, it will work, but it will never be a killer, all out turbo setup. I suspect turbos big enough to get the car into the 11's or faster would end up with too much lag no matter what you did (possibly with killer, top of the line, bb turbos...).

do they give any indications where they run intake ducting? sucking air in from under the car is just bad (on a sunny day it will be 20-30* warmer then from in front), it will be exposed to water spray... and I don't know where you can run a fairly large pressure side tube that isn't going to be next to the exhaust (absorb heat from it) or cause ground clearance problems.

From what I gathered the intake could be mistaked for a CAI so I'm assuming that the intake piping is either in the stock location (or wheel well) or somewhere in the engine compartment.

I'm going to go down there this week and take a look at it.

Apparently they have taken a stock 95Z28 (low 15's@89-95 or so at our altitude) and installed nothing but the turbo and have run a 13.0 @111.

Before I read that post a friend of mine ran into that Camaro when he was out and about and I was shocked to hear the placement.

The ground clearance problem I was thinking about is the turbo itself....again I haven't seen it so I'll see if I can get some pictures of it this week, if not then I'll just have to describe the placement. The underside of an fbody is precarious enough as is not to mention having a turbo underneath that I would be afraid of tearing off if I hit a dip that I'm not expecting.

I agree that a turbo regardless of placement, length of piping, etc is going to improve performance and from what they say the results of the test on their stock Z28, it seems impressive....

Anyway.....I'll update as soon as I see it.

well, im definetly a skeptic of a rear mounted system.

but after reading the thread, the guy SEEMS to be on top of things, and knows what hes talking about.

my guess is that this will be a good system for a stock or moderately modified car, but probably will not be strong enough for a serious drag race application. which is fine, because most buyers are just looking for a bolt on solution like a supercharger.

I talked to the guy yesterday and I am significantly impressed. The Garrett factory guys came out to look at the set up and from what I understand they were impressed enough to want to offer this system through Garrett.

This setup represents a very novel step in turbo technology. Unless Ghost (you b@stard Dustin) gets first dips I am going to try to build a SIGNIFICANT setup with this company this fall.

A couple of other things about the system. There are no mufflers. That is where the turbo is mounted. Thus no ground clearance issues.

BBB

That guy does know his stuff. The only thing that I would have a problem with is matinence. Since most people who are adding turbos to their Camaros are trying to get lots of power, and this brings lots of rebuilds, and fixing things.
If the turbo is under your car at the rear, how the hell do u get at it without lots of trouble?
That would be my only gripe I think. Running a whole bunch of intercooling and intake plumbing would bea bitch too, but maybe he's got a soultion for that too. Sounds cool though.

Hunter

Originally posted by teamsleep13
That guy does know his stuff. The only thing that I would have a problem with is matinence. Since most people who are adding turbos to their Camaros are trying to get lots of power, and this brings lots of rebuilds, and fixing things.
If the turbo is under your car at the rear, how the hell do u get at it without lots of trouble?
That would be my only gripe I think. Running a whole bunch of intercooling and intake plumbing would bea bitch too, but maybe he's got a soultion for that too. Sounds cool though.

Hunter


well i would think a turbo at the rear of the car would be MUCH easier to get to, rather than in the cramped fbody engine bay.



my question is how the hell does the turbo oiling system work?

Originally posted by got_hp?
well i would think a turbo at the rear of the car would be MUCH easier to get to, rather than in the cramped fbody engine bay.



my question is how the hell does the turbo oiling system work?

That is exactly why I think it is a great idea. Where do you put a turbo in an F-body engine bay that 1500-2000 degrees is not going to do bad things to?

Also the long pressure tube acts like an intercooler (to a point).

As for oiling. Does the turbo care whether its oil line is 2 feet or 15 feet?

BBB

Oops ya I forgot we are talking bout the LT1 engine bay, I was thinking on my 68's engine bay where I got tons of room. Putting the turbo in the rear does sound like a good idea.

Also the long pressure pipe being an intercooler....that would be a great benefit I think, plus you could probably get the pressure pipe to have some fins on it to act like a heat sink to improve this even more.

Ya oiling might be a bit more involved, but it should be on turbo's. Maybe a seperate oil pump would be a good thing, plus some hard line. You could even do a seperate oil system for the turbo to keep it really happy, but that is a bit overkill.

For my car I have been throwing around the idea of ceramic coating the entire exhuast system to keep the exhuast hot and flowing fast, and on this application it would work great I think. Coating the entire exhaust pipe going to the turbo with either Jet Hot or something similar, even one of Swain's ceramic coatings would keep the exhuast velocity really high, and help witht the spool up and efficiency of the turbine. Of corse this is another overkill suggestion, but isn't that the definition of modding our cars anyway.

Hunter

I've done a lot of work with turbos, and I think that 'turbo at the back bumper' stuff is pretty half ass... 3 things to keep in mind, all else equal:

1. More exhaust volume before the turbo equals longer spool up time.

2. Colder exhaust temps equal slower spool.

3. Larger intake/ducting volume adds lag.

That's going to be one laggy, unresponsive, inefficient turbo setup...

Originally posted by EddieP
I've done a lot of work with turbos, and I think that 'turbo at the back bumper' stuff is pretty half ass... 3 things to keep in mind, all else equal:

1. More exhaust volume before the turbo equals longer spool up time.

2. Colder exhaust temps equal slower spool.

3. Larger intake/ducting volume adds lag.

That's going to be one laggy, unresponsive, inefficient turbo setup...
Lets us put it simply this way. When it comes to this system you are wrong! You are thinking conventionally.

This system has already been proven on a BONE STOCK car. It dropped almost 2 1/2 seconds off its 1/4 mile time and added 14mph. It has been kicking butt on VERY put together cars already.

BBB

First, the guy doesn’t “really know what he’s doing” but is a good sales man. He actually gives 2 different descriptions for how something works in that one thread, both of them partially wrong.

He is correct that you can size the turbine side smaller and get good spooling, but the distance between the turbo and the engine will always cause lag, it’s just a matter of how small you’re willing to go to get rid of it. FWIW, he’s gone pretty small, which is why it’s working. I don’t know what turbo he’s using but I suspect that the whole combination wouldn’t work as well at sea level.

Oiling… that’s an interesting thing. The feed isn’t that big an issue, as long as he keeps it small enough that the stock oil pump can keep up with it. OTOH, the return would pretty much require it’s own pump mounted back by the turbo. If you’re going to run a pump back there anyway, I don’t think it would be a big deal to mount a little tank and build it’s own, dedicated oiling system. Another alternative would be to go with a turbo with a self contained oiling system, but I don’t know of any that would be large enough and they’re all super expensive.

I still think that the biggest problem in the long run will be the location… not a good place to cool things, water splashing will cause problems with both the air intake and the turbine housing (if it cools the turbo will work differently, if you really get it working and then splash it, it will crack).

All that being said, I’d still love to see the setup… any of you that have appointments to see the thing if you can (if he’s willing) try take some pics and post them here…

What I've said is 100% correct in every case... all else equal, longer exhaust and intake tracks and colder exhaust will make the system less effective - no ifs, ands, or buts. Here is something else you can take to the bank: a similar car with the turbo up front will wipe up the floor with that car and the turbo mounted where the muffler is.

Originally posted by BBB
Lets us put it simply this way. When it comes to this system you are wrong! You are thinking conventionally.

This system has already been proven on a BONE STOCK car. It dropped almost 2 1/2 seconds off its 1/4 mile time and added 14mph. It has been kicking butt on VERY put together cars already.

BBB

The question I have, is why did he try it in the first place? I mean how did this idea come to him? Curious to see how he came to this choice.

Hunter

EddieP is right. Large intake and exhaust volumes between the turbo and engine will make lag a huge problem. But it sounds like the maker modified the turbine housing size (smaller) to compensate.

If he made the turbine housing undersized to make it spool up quicker, the exhaust flow through the turbine will be restricted. It works like this: If the turbine is small, spool up is quick, but backpressure is high. If the turbine is larger, spool up is slow, but backpressure stays lower.

So, the band-aid for slow spool-up will decrease power.


At a drag strip, turbo lag isn't usually an issue since the turbo stays spooled-up all the way down the strip. Turbo Buick guys have been installing huge turbo's on the little 3.8's for years because they perform well at the track, but street response gets really soggy. So, saying it's proven because of its track time doens't say anything about driveability or lag.

Mike

If you buy this setup make sure you park your car in the garage or some riceboy will come steal your turbo.

I'd really like to see a pic how everything is run. I think it sounds really interesting, but even with that long of a run for pressure piping and no intercooler, I would still run the water injection. If you would ever work on my car with the lack of room under the hood this rear turbo sounds like a heaven sent idea :D Its really interesting though. Imagine a turbo system with hooker long tubes!!!

Bill

All you guys are soooo right. Can't work...etc. I'll let you know how bad it sucks here in a couple of months.


BBB

As the Imortal Buford T. Justice said in Smokey and the Bandit.. Junior Remind me to kick ya momma in the butt. (all in fun guys)

I just do not see this system working and read alot of responces but some were taking word for things that i just don't know about..

First and foremost the oil situation.

Turbo in the rear of the car wonderful... How are you going to pump the oil there and back going to have to have one heck of a pump to push the oil that far back at a nice pressure. Then since there is no pressure on the return of the oil you are going to have to pump the oil at a high volume back and this is prob going to need a very nice pump to handle the heat and load of constant use.

Next issue Lag..

Ok think of it like this. Two air compressors same compressor setup, BUT one has a tank and one does not. Now we know that there is a volume of air on both the exhaust and the intake of this setup that we can show as the tank setup.. Which one reaches 100 psi faster. Once the car is on boost it prob can keep up with the boost but you are going to have to load the car seriously hard to get boost and keep it IMO. Just chassis dyno a turbo car you will see what I mean, then go on the highway in 5th gear and wot. Using a/r housing to make up for spool time great.. but at some time it is going to flip flop on you whether or not it becomes a restriction.

AS for gaining 14 mph in the 1/4 you can load the turbo for whatever amount of time and then launch, as Mike said once loading up the car and getting boost you are not worried about spool up since most of the time you are wanting to leave the line SPOOLED UP.

As some others have said isn't Heat energy... If you are trying to get rid of heat aren't you loosing energy...

Hope it works for the guy but I just do not see that happening.

Steven

Well I wasn't able to get down there today, hopefully I will be able to make it down there tomorrow and I'll see if I can get any pictures of the setup....if anything, I'll just describe it as best I can.

I'll make it a point to check on oiling of the system.

This is a reply to the oiling question on our local site. The thread is located at
http://www.ufba.org/forum/index.php?board=16;action=display;threadid=3476;st art=20


As for oiling question, yes we do run an oil pump. Our oil system, as well as remote mount, is patent pending. It includes a wet-start system to instantly lubricate turbo at startup. It also cools the oil before it gets to turbo and then again before it returns to engine.

I will try and get some pictures up on our web site soon. We are still in middle of building the web site. You are welcome to come by the shop and check out our stuff if you are in the area

Rick @ STS 801-979-6554


Call Rick

BBB (I'm not Rick and have no association with his company)

What if they tapered the lead pipe? Say you leave a 4" collector at the y-pipe and taper it down gradually to the turbine inlet, which may be 2.5"? That would cover about a 6-7 foot tract I think, which should help to keep velocity up as the gases cool. Or you could even ceramic coat the pipe to keep as much heat in as possible.

But I, too, am a little skeptical of this setup. Seems like it would suffer the same fate as the Turbo Tech kit; it's great for a bolt-on car but would really be hurting in the higher hp apps. Close to the engine is where a turbo belongs, IMO.

Not saying it sucks or anything, but about all that has been said in this thread is exactly what I've been experiencing for years in the build-up of my Buick. It should suffice in a mild 11 or even 10 sec V8 setup, but I wouldn't look too much further than that before having big headaches with tuning. Maybe with a big-cube stroker and GOOD heads in a good state of tune, but not a whole lot farther.

Just my $.02

Although I agree with the general sentiment (not a good idea)… it’s not as bleek as people want it to sound.

Originally posted by zturbo
First and foremost the oil situation.

Turbo in the rear of the car wonderful... How are you going to pump the oil there and back going to have to have one heck of a pump to push the oil that far back at a nice pressure. Then since there is no pressure on the return of the oil you are going to have to pump the oil at a high volume back and this is prob going to need a very nice pump to handle the heat and load of constant use.

The pressure just needs to stay between 20-50psi when the turbo is under load.

Assuming that you run a typical ¼” (an-4) feed, we’re talking about an additional .02quarts of oil… and the return pump will have to move roughly .5gallons/minute… really a rather insignificant amount.

Next issue Lag..

Ok think of it like this. Two air compressors same compressor setup, BUT one has a tank and one does not. Now we know that there is a volume of air on both the exhaust and the intake of this setup that we can show as the tank setup.. Which one reaches 100 psi faster.

As long as you’re not running an intercooler with this setup (unnecessary with mild boost at high altitude), this is a non issue. The volume of the intake charge tube (probably 2.5” at most) running the length of the car is likely smaller then the volume of most intercoolers.

I still really doubt that you’ll get significant cooling running a long tube through that (relatively hot) area.

Obviously, he’s running a small enough turbine housing that it’s spooling fine with a relatively small exhaust volume, so that’s not an issue till you try to make more power.

Again… the combination works OK for an engine at high altitude… I’d like to see him drive it down to sea level and run it at a track without race gas and not blow it up.

As some others have said isn't Heat energy... If you are trying to get rid of heat aren't you loosing energy...

This is EXACTLY why it will never be a killer, all out turbo setup. The fact is that we’re really awful at getting the energy out of the gas that we’re burning. We manage to get roughly 10% of that energy out to someplace that we can use it. If you allow it to dissipate as heat before you use it that small percent that you actually manage to harness becomes that much smaller.

WS6 is 100 percent right when he said

This is EXACTLY why it will never be a killer, all out turbo setup. The fact is that we’re really awful at getting the energy out of the gas that we’re burning. We manage to get roughly 10% of that energy out to someplace that we can use it. If you allow it to dissipate as heat before you use it that small percent that you actually manage to harness becomes that much smaller.

A third of an engines power out put goes to the crank, while the other two thirds go to the cooling system and out through the exhaust.

The purpose of a turbocharger is to harness wasted energy (heat) from the engine, which is exhaust. To harness that enregy the most efficiently, you want it straight out of the exhaust ports and into the turbine. This will give you the most effcient use of the exhaust gases.

Now if you put the turbo at the back of the car, of course it will work, and it will probably work quite well if done properly, but as some have said, no where near what could be done with a turbo as close the the cylinders as possible.

Loosing all that heat with a turbo at the rear isn't really worth the benefits(which im still trying to come up with) it could bring. I like to have things as efficient as possible, and keeping the turbo up front is more effcient.

From all of this I still say, to each his own. Diversity is what keeps the automotive industry thriving.

Hunter

Well I went down and checked out this setup the other day and I didn't have my camera with me so I'll describe the setup as best I can.

The intake tubing replaces the stock I-pipe and runs along the same route coming up over the axle and parallel with the axle toward the drivers side which is where the turbo is mounted. The air intake for it is basically where your drivers side talipipe would be. The charge line runs the full length of the car along the drivers side of center line and comes up front and into the intake like a normal CAI would.

He states that he has never had any problems with debris into the filter nor has he had a problem with water splashing on the turbo (turbo is placed basically where your stock muffler would be).

There is an oil pump on the return line but the biggest problem I see is that there is no room for the charged line to run if you have headers....only stock manifolds.

And since we all know how heavy and restrictive the stock manifolds are, not to mention how much of a PITA it is to change plugs with stock manifolds....that and a few other things were enough for me to leave the shop.

So if anyone is wanting this turbo kit, they better keep their stock manifolds or sell their newly installed FLP's (BBB ;) )

As for me....I'm still waiting to see what www.turbolocity.com is doing with their setup.

Originally posted by GhostZ

So if anyone is wanting this turbo kit, they better keep their stock manifolds or sell their newly installed FLP's (BBB ;) )



That is what I am going to see about. We talked last week for a while and it seems that he is interested in stepping up to header cars. We will see....

BBB

here is my dialogue with him, just in case people are too lazy to goto the other board.

me: does the system only work with stock manifolds, or will it work fine with after market long tube headers?

also.........without testing this kit at sea level, what changes have you made to insure that it will operate properly for other people who order it.........or is it just for local guys?

him: This kit is designed to be used on a stock LT1. It clamps on to the exhaust system just like the stock muffler clamps on. The problem with headers, a couple anyway, is that the air charge tube probably won't have room to run up into the engine compartment with headers on. Also, headers have a hard enough time not leaking with no pressure in the exhaust system, let alone the backpressure produced by a turbocharger. Headers won't really give you a performance gain on a turbo application like they do on an aspirated or supercharged application because your exhaust system is really only as good as the smallest orifice (restriction) and the turbo is alot smaller than even the stock manifolds. The rules are changed when you enter pressure into the equation. That is one nice thing about turbos is that you don't have to spend alot of additional money on expensive exhaust, big cams, and high flow heads. You also get to retain the driveability and fuel mileage of a stock vehicle.

As far as sea level goes, we are still in pre-release stage of the kit and looking for a good test vehicle at near sea level elevation. They obviously won't be able to run the boost there that we do here w/out some modifications. Stock system should handle about 5 psi boost at sea level.

me: hmmmmm..............id say that you are going out of bounds saying that a turbo system does not benefit from larger headers/exhaust manifold.


in ANY turbo application i have every seen, you can always pick up power when switching from the stock manifold to a well designed aftermarket one.

no to mention, the stock manifolds are horribly restrictive, and terrible for plug access.

him Sure, there will probably be some gain in a better flowing manifold but not the gain you get in a non-turbo application. Think about it, The hole in the turbocharger that all of the exhaust (except wastegated) has to pass through is roughly the size of your thumb, so how big of primary tubes do you think you need if you have a 1" collector (so to speak)?




i left another post saying how 90% of the people that might buy his kit have aftermarket headers, and are not willing to go back to stock manifolds, so he will have to change things if he wants to sell it.