Supercharger Rebuild

[cnidy1230]

My name is Chris and I am new to this cite, so hello all. I plan on puting a custom super charger onto my 92 XJ with a I6 4.0. The supercharger is off a 00-04 nissan exterra. I have another engine in the garage and plan on building it up but still not sure about stroker engine. main problem is i have the stock AW4 and cant find upgrades for this. thought about th350 upgrade with advanced adapters help. still not sure that is the way i want to go any help/advice would be great.

[Beej]

My name is Chris and I am new to this cite, so hello all. I plan on puting a custom super charger onto my 92 XJ with a I6 4.0. The supercharger is off a 00-04 nissan exterra. I have another engine in the garage and plan on building it up but still not sure about stroker engine. main problem is i have the stock AW4 and cant find upgrades for this. thought about th350 upgrade with advanced adapters help. still not sure that is the way i want to go any help/advice would be great. This thread will likely be moved to the street/performance forum. There is a lot of info in there regarding boosted 4.0's. The AW4 will comfortably handle 400hp, so unless you are shooting for something beyond that, you'll have no problems. (Other than a blown motor :D ).

For performance enhancements on the AW4, check out Level 10 Performance...

http://www.levelten.com

[5-90]

The AW4 was designed by Toyota, and is used in their RWD Van, automatic Pickups, and the Celica and Supra (yes, the turbocharged version of the Celica.) It's also found in some RWD Lexus applications.

Why is this important? It helps to open up the field...

I believe Level Ten (Google them, I don't recall the URL) offers some upgrades for use with the 03-40/AW4 slushbox, so that should be a good starting point.

As far as the blower itself, can you be more specific? I know you said it's off of a late Xterra, but does it have any "maker's marks" on it? I'd be almost willing to bet it's an Eaton or a Whipple - or a knock-off of either one. Most "two-rotor" blowers are fairly simple devices, but I'd hate to give you bad info...

Meanwhile, welcome aboard, and I hope you learn a lot!

5-90

[cnidy1230]

I beleive it is an Eaton. i saw a post on this cite saying the AW4 will handle 400hp and that gave me hope to keep it. the supercharger runs about 6 psi stock so that will give me around 350 hp if i run a stock engine.

[Beej]

Well, not quite 350hp. More like about 260-270hp...

[cnidy1230]

right, sorry wrong calculation

[5-90]

350hp may be a little, er, "optomistic," but here's a rule of thumb...

Take the peak power output of the engine.

Take the boost you're going to feed it (in atmospheres.) Add one. (for instance, a 6psi boost would be 6psi/14.7psi, or ~.4ATM. 1.4ATM total.)

Multiply the output figures times the number you get from the second step above. Figuring, say, 200bhp for peak output, that means 200bhp x 1.4 = 280bhp

Granted, this is horribly over-simplified, but it should serve to give you an idea. It's also optomistic in itself, since it does not account for adabiatic efficiency of the blower, charge air cooling greatger than 100% (charge air ends up cooler than ambient temperature,) parasitic drag, or any of a number of other factors, but it's a good ballpark to work from.

Once you start to firm up your numbers, you can then run a simulator (Desktop Dyno or similar) to get a better estimate.

Also, bear in mind that, just beacuse the blower makes 6psig boost in its original setup, doesn't mean the same setup is going to make 6psig for your engine. I'd be willing to bet it came off of an engine with a smaller displacement (lowering the effective boost,) and that the crank/blower pullys will also need to be changed to maintain boost. There's a lot more to supercharging an engine than just sticking on a blower... However, a lot of us are willing to help you.

While we're on topic, I am going to move this to "Street and Performance" - since it more properly belongs there - and thank Beej for saving you Googling Level Ten (I couldn't recall the URL offhand, and didn't want to post a dead link...)

5-90

[Beej]

Jon's right on (as usual). I just researched that supercharger you've got and if it is indeed from an XTerra, its an Eaton, Roots-type, but unfortunately its only rated at 3.5psi of boost on the XTerra. Assuming those numbers transfer to the XJ 4.0 (which they probably won't exactly), that's going to give you about a 24% increase, or around 235hp.

Assuming you can get more boost out of it though, it should be good to go. From what I've read here, I don't think you can put more than about 7psi through the 4.0 without some significant internal mods...

Hope this helps...

:thumbup:

[cnidy1230]

thanks again, I looked at the wrong figure on my paper. This will be my first blower install and first fuel injected engine rebuild. I am used to building big horse other ways with a carb engine. I have found alot of good info from the Internet on things to check for and prepare to do.

[Beej]

It should only be a matter of a few swapped out parts for more boost though. I bet you'd get some good info by contacting Eaton directly.

[5-90]

Jon's right on (as usual). I just researched that supercharger you've got and if it is indeed from an XTerra, its an Eaton, Roots-type, but unfortunately its only rated at 3.5psi of boost on the XTerra. Assuming those numbers transfer to the XJ 4.0 (which they probably won't exactly), that's going to give you about a 24% increase, or around 235hp.

Assuming you can get more boost out of it though, it should be good to go. From what I've read here, I don't think you can put more than about 7psi through the 4.0 without some significant internal mods...

Hope this helps...

:thumbup:

Getting more boost is usually a matter of selecting pullys with more overdrive to them (smaller snout pully and/or larger crank pully.) This will change the drive ratio at the blower snout.

Also, what displacement was the engine that it came off of? That would generate a significant correction, as I'd mentioned (fixed-displacement blowers generate boost based upon the amount of air they can feed related to the basic air movement of the engine they're bolted to.) Isn't the Xterra engine somewhere around 3 litres? That means a 30% reduction in boost, before anything else is accounted for - simply due to the larger displacement of the AMC242.

Eaton pullys, however, should be fairly easy to find - and any competent machinist can make them on a lathe, if it comes to that! You may still run into a ceiling based upon the model of the blower you're dealing with (Eaton fields four for production vehicles, as I recall. I should have compressor maps around here somewhere...) and you'll really need to know! The difference between the four is the basic displacement - the amount of air each blower should move per revolution. I was originally looking at, I believe, the second largest Eaton - until I got into Whipples (increased efficiency, don't need to run them as fast, increased thermal efficiency) and I've been working on ideas for a Whipple and a fabbed intake...

5-90

Oh - and contacting Eaton directly may not work. Try Magnuson Performance first - but you're probably going to end up having to get a few things made. I'd also say try contacting Kenne Bell (since they do the Whipple kit for the TJ,) but they don't mod the intake manifold, and there would be some hood clearance issues putting a blower on top of the intake and trying to close the hood - the KB TJ kit comes with 1" pucks for a body lift...

[cnidy1230]

the easiest way to increase boost i found is pulley size. many people have done it on the exterra and i guess get a good increase in boost. i will see, alot of brackets and fab work to do still. still in the research stage of this project.

[Beej]

Keep us posted...

:wave:

[cnidy1230]

clearnce i can do. already started and almost done with an 8 inch cal hood. i beleive a 3.3l is in the exterra. already sent an email to magnuson since they do most everything for eaton. i gained alot of info from kennebell to help so far. I have availability to a machine shop so I can make about anypart I would like to. as long as i know what i need. i beleive it is a m62 from eaton but have not comfirmed it yet still working on that.

[5-90]

the easiest way to increase boost i found is pulley size. many people have done it on the exterra and i guess get a good increase in boost. i will see, alot of brackets and fab work to do still. still in the research stage of this project.

Correct - what you're doing is changing the ratio of crank drive speed to snout driven speed - and you're usually driving it faster to make more boost.

We do have an advantage in that the AMC242 actually likes being run at relatively low crankshaft speeds (mine lives at about 2800rpm!) and that means you're probably not going to end up "overdriving" the blower. However, since it's also a relatively large engine (over 200cid,) you may just want to think about getting the next size larger blower - like the Eaton off of a T-Bird or a Bonneville (~3.8 litre V6, should be the next blower up from that on a ~3.0 litre V6. 230-ish cubic inches, vice 170-ish.)

Also, the headache you tend to run into at higher boost levels (higher speeds) is "internal leakage" - where the compressed air actually ends up leaking backwards past the rotor tips and ends. This is a variety of "parasitic drag" that you may end up having to account for - and why it's better to use a larger blower, driven slower; than to use a smaller blower, driven faster. Ditto pretty much anything - always remember, TANSTAAFL ("There Ain't No Such Thing As A Free Lunch" - Robert A. Heinlein, The Moon is a Harsh Mistress.) You have to be ready to trade one thing for another - the more you want, the more you have to trade.

I'd be perfectly willing to help you figure out how to get where you want to go - I've got most books on performance at hand (including one I wrote myself!) and I've got some decent sim software and I've already done most of the research into performance parts for you. Frankly, I'd have damn near killed to have someone like me handy when I was building bracket engines, and had to figure all of this stuff out on my own! You can't get too much help or too much information on a project like this - you can aways just write it down for another project if you don't end up using it for this one. That's how I learned most of what I know...

5-90

[cnidy1230]

back to tranny. ya'll say that most parts for the celica, supra.... toyata stuff will fit? how will i know for sure? have you seen anything to build more line pressure like some auto deisel trannies offer?

[Beej]

BrettM at Awshifting.com makes some neat toys for the AW4...

[cnidy1230]

I see what your saying, that internal leakage will also boost temp if I remember right. wich is no good. will keep this in mind.

[5-90]

I see what your saying, that internal leakage will also boost temp if I remember right. wich is no good. will keep this in mind.

Correct - you'll get temp climbs from compressing the air (Boyle's law, or was it Pascal's? It's been a long time since high school phyzzies) and from the friction you get from leaking air (it's not much, but it's certainly there!) The bulk of the temperature increase will come from compression - that's why turbos usually run charge air cooling (commonly known as "intercooling") due to the higher boost levels you get. The point of diminishing returns for running boost without charge air cooling is, as I recall, 7.35psig (or 1/2 ATM,) but effecient cooling will always help - anytime you cool the air charge, you make it denser. Denser air = more air for a given volume = ability to burn more fuel = potential for more power.

As far as the line pressure increases, I'd start by checking with Level Ten. I haven't had to look into doing it with the AW4 so much - and when I was doing this sort of thing regularly, I was working with cast iron Powerglides, THM350/400, C4/C6, and A727 (none of which are anything like the AW4 inside!) I tend to prefer manuals anyhow - you just find a clutch shop that can put stronger spring packs in the clutch cover, and call it good.

5-90

[cnidy1230]

thats why I am here cause I am used to the C-6 or manual trannies. i can rebuild them but not sure what to do with this thing. lol good thought about the clutches, ya'll think AW4 is pretty good it sounds like so unless I really go big I think I can make it work.

[5-90]

Well,

Shortly after I got my first XJ (ca. 1995,) I found out it had a slushbox I wasn't familiar with. I went to a salvage outfit and got a core for $75 so I could tear it to bits and figure out how it worked. I ended up getting a rebuild kit, and putting it on the shelf as a spare for if and when.

ca. 1997, I started having trouble with that slushbox in my 87 - I found out it was because I'd lost three bellhousing screws, and the fourth one had backed out about a half inch. I replaced it with the one I had under the shelf, put in new bellhousing screws, and proceeded to tear apart the one that "failed." (not its fault.) The first planetary set had gotten off-centre in the case (due to the misalignment of the crankshaft centreline and input shaft centreline,) and I needed a Sawzall to get it out - most of it ended up in the scrap metal bin, since I had to cut up the case.

It was worth noting that, at ~220kmiles on the clock (and some serious abuse for the last 110kmiles or so...) the clutch friction was nearly new, and there was little to no accumulation of crud, varnish, and sludge in the case. I kept the valve body, solenoids, and some other parts for spares - still have them.

I think the AW4 was AMC's atonement for using that damn Peugeot 5-speed behind the 4.0 (I've been through about five of those in the last three years...) since it seems to be rather drastically overbuilt for the application. I'd have no trouble using it behind a stroker or some slight forced induction, with no mods but a decent external cooler. It's been compared favourably to the THM700R4 - and for good reason! I've been through a few 700's, and the AW4 is simpler and more robust just upon examining the parts!

I haven't checked Level Ten in a while, but I seem to recall them having some decent-looking parts for the AW4 (I haven't had need to try them just yet,) and I'm mildly amazed that there isn't more out there, since it's a fairly widely-used RWD/4WD slushbox. I'd still take an old Muncie top-loading "Rock Crusher" over any slushbox - but if I had to take a slushbox, the AW4 is on my short list (which reads something like CI PowerGlide, AL PowerGlide, THM400, A727, AW4, C6, THM350, ...)

All in all, the AW4 is pretty damn decent for a slushbox, and to do significantly better, you'd probably have to get one from Alison.

5-90

[BrettM]

Level 10 and IPT both have modified valve bodies. It's the same tranny as the Toyota A340, but I don't think they have it listed for Jeep applications on their page since almost no one with Jeeps upgrade it. Call them, they'll know what you're talking about.

http://www.importperformancetrans.com/
http://www.levelten.com/

[Dr. Dyno]

Well, not quite 350hp. More like about 260-270hp...

Yeah, a 190hp 4.0 can be boosted to about 255hp with a 6psi supercharger and a 260hp stroker can be boosted to about 350hp.

[cherokeekid]

I have an xterra blower I was planning on mounting as well. Curious to see how you are going to mount it. originally I was going to just mount it atop the intake manifold but I would need to modify the fuel rail, then I was looking at cutting a stock 99+ manifold and tig welding the blower at an angle.
I had already made an adapter for the TB and a plate for the bottom. The last way I was going to mount it put the TB in kindfof a funny position though.

With my psc P pump coversion, OBA, 2 batteries I'm about out of room and probably going to scrap the idea and either play with a turbo or just stroke it. But I am extremely interested in seeing any progress.

[cnidy1230]

sorry to say I have not gotten real far yet. waiting o material and space in the machine shope to make my bottom plate. I am useing 1 inch aluminum stock. wht did you use? i plan on siting it right on top of my manifold and makeing a plate for it to sit about 2 inches above manifold. still need a bracket in front to secure it and an idle pulley. once i start i will post pics. good luck on yours.

[cherokeekid]

IIRC I used 1/2" aluminum and 3/4" for theTB adapter, I was going to cut the intake man and tig the blower on a an angle to avoid messing with the fuel rail and be able to close the hood. With my current set up there just isn't enough room. the blower itself seems like a good choice; no oil lines to run, the intake side is the same size as a bored HO TB too. the only drawbacks I was running into were the placement of the TB (not really that bad) and then simply its size.

[cnidy1230]

I made a custom 5 inch cal hood not too long ago and will have it on when I do his install I hope It will be tall enough. I do believe it will clear. for a custom job i dont think it will be really hard to fab. what fuel upgrades where you planning? you can run an extention like the stock exterra had for the throttle body for a better postion. I think they where like 6 inches longand moved it closer to the front of the compartment.

[cherokeekid]

I have an adjustable map sensor and FMS injectors, I was going to start with that and look into an aftermarket eng mgmt system if it didn't cut it. if I flipped the TB the throttle cable looked like it could be routed to fit pretty easy. looking forward to any pics.

[FatXJ]

I was led to believe that the Nissan blower is the same M-90 that was used on the SuperChicken and Bonneville/GrandPrix motors but with a different plenum and pulley.

[cnidy1230]

I heard the same thing but have not been able to prove it with part numbers.

[Pharaoh XJ]

I thought this formula might come useful
boost = (pulley ratio x 14.7 x SC displacement / half engine displacement ) - 14.7

in case of an M90 on a stock motor and 6 psi
(ratio x14.7 x 1,484 / 2000) - 14.7 = 6
then ratio of SC pulley to crank pulley = 1.89:1

[Pharaoh XJ]

check out avenger s new website
http://www.avengersuperchargers.com

[cherokeekid]

Sorry if I'm getting off base:


There is no way I am going to get the xterra blower to fit with all my stuff. I came across a lysholm blower off a 2.5 mazda millenia, apparently these are much more effecient but produce a great amount of boost. Any info on them? My thought process (may be way outta whack); it is a more effecient design and with the larger displacement of my 4.0 I would get a managable amount of boost. thoughts, links etc?

[cnidy1230]

how comparable is the engine size? 6 psi boost on a smaller engine may not be 6 psi boost on a 4.0l

[cnidy1230]

avenger superchargers new cite sure doesnt share much good info about there system.

[gbaronetXCR]

Have a boost project parked, cuz I need to swap engines. The orginal 4l has 320Km on it. I do have a fresh 4.2 I was going to swap the 4L head onto and use it.
Been into a lot of boost lately and use my GTP more for daily stuff.
The exterra does use the M90 in a nissan housing, each vendor ends up using thier own manifolds incorporating the blower.
I picked up a Ford SC M90, cuz it self contianed, but is big and will replace the AC unit and area.
I was shooting for 6psi~ using a stock 3.8 GTP pulley for starters
Did not have a estimate for Hp, figure more than this stock mill was better. I pull sleds and a boat, and find her underpowered.
My old thread... http://www.naxja.org/forum/showthread.php?p=243344367#post243344367

Good luck , will be watching.

[cnidy1230]

cant find your pics do you still have them? interested in seeing hem for mre ideas. stumbling on where to start. been busy but wil have time next two months. so hope to start soon.

[seanyb505]

I always thought that with a turbo or a supercharger you would have to significantly strengthen the internals of the engine. From what ive gathered reading this, it would be safe(but not wise) to run up to around 7 psi on a 4.0?