I'm going to be running a ported Eaton M90 on a 305 TPI. It's in my 95 suburban, daily driver. I'll be using the Megasquirt II 3.0 ecu. - The set-up is for efficiency, not major power. - My question is do you guys think I would be better mounting the blower off to one side and plumbing into the TPI or modifying a single-plane(carb) intake to accept the injectors and the blower and just mounting it direct? I know I could run an air-to-air cooler w/ the remote mount, but I could easily run a water-to-air between the blower and the manifold(even thought about plumbing an a/c line through it...) - Mostly what I'm wanting is opinions on power vs efficiency for each mount style, so for this post, just throw out the intercooler.

what do you guys think?

also, don't rag on the M90. Others have done it, easily makes around 6psi stock(around 550 cfm - can be pullied to around 8) and a ported version flows about 650 cfm, so plenty for a 305 turning around 5k. I'm looking for the ability to make about 8psi, but I won't be using that often, as I'm setting it up for efficiency.

 

I would think a single-plane conversion would really be for a much more performance-oriented application. They work well in the upper RPMs vs. a TPI that's the grunt-champ at rediculously low RPMs (which will complement a roots blower nicely, especially in a truck, street driven, towing, off-roading, etc.).

Why make life more complicated than it needs to be? Side-mounting a roots is probably going to a little easier than custom-mounting it on top of a modified single plane anyway, all things considered (all the things you have planned, anyway). And an air-to-air is very straight forward vs. an air-to-water sandwiched between a blower and a single plane intake.

Do all the puts-and-takes...... keep it simple and you'll probably be happier with the results. Hanging a roots off to one side of the motor and tuning it is going to be plenty challenging without the added complication of a completely different intake system.

Plus I like the idea of a TPI intake combined with a roots blower. It's gonna hit like a damned sledge hammer when you lay into it.

 

that's just the kind of answer/opinion I was looking for. Anyone else? As I said, I'm just looking for opinions and reasons.

also, I like this:

 

also, I think tuning w/ the MS system will make it a lot easier. On the fly w/ a 3-bar MAP can't hurt any...

 

- also, I'm planning on running the M90's internal bypass valve. - If I remote mount the blower I should hook the vac line up to the TPI plenum, correct? I believe it needs to be behind the TB to work properly?

- If I run the bypass, it'll really help w/ the blower's efficiency, and I can run a metering valve(dash mounted) in the vac line to control the waste amount/boost rate...

anyone?

 

Am i the only one who thinks the M90 is too small for a 5L engine?

 

TPI does not help when you are using a roots blower, the long tuned ports are only a restriction. The extra tourqe you get from the TPI is only in an short RPM range, and turning the blower a fraction faster would compensate for that and more.

You can still use the TPI but the gain from being a 'tuned port' is gone with the blower.

Adding an intercooler is a good idea.

 

There's an Eaton M112 on ebay for 500 that i think would be better for a 5L then the M90. But if you alread have the M90.

I have a 2.2L Whipple kit on my crate 350. Tranny blew on the dyno this week so it's currently getting rebuilt.

 

edit

 

I already have the M90(freebie, neighbor own's a junk-yard). Stock, Eaton shows flow to be around 550 cfm, ported it can make about 650 cfm. - 650 is more than enough to feed a 5.0L to 5,000. The reason I was thinking of running the TPI is because running down the highway, you're not under boost. So, now you have to pull a suburban on 33's(sometimes towing a 28' enclosed trailer) on motor/intake. If I were to cruise under boost, I'd be negating the possibility of economy and it'd be hard on the motor.
I just want to use the blower to help me get rolling(plus passing/etc, especially when towing), that way I'm using less throttle.

Am I wrong? - I'm sure I probably have been before...

 

Hi,
I have not posted here much. So here it goes. I am currently doing a M112 from a lightning onto a Mustang. Yes Mustang.

Couple of questions. I do not know your fabrication skills or equipment you have, but you are going to need a lot of stuff(skill/equipment)even if you hang it off the side and or make an intake for it. I am going through this. I am having the adapter CNC'd. Just the block of alum alone was 180.00 (you can see the plate in the pic). I have a Bpt machine, but did not want to spend hours milling an adapter plate for it so me friend is CNCing for me. The inlet box alone took hours and hours to make. Do you have one from a T-bird cause they blow in the upward direction(on thing to remember). The lightnings and the cobras blow down.
Here is a link of my project so far. I also have to extend the main-shaft snout to allow me to run only one serp. belt. Hope this helps you out some.

http://www.tjsperformance.com/eatonm112.htm


T.J.

 

fabrication is not an issue. I understand the idea of the billet adapter block, but you could also easily fab/weld a "plenum" up to do so. - anyhow, the blower is the GTP style. I intend to cut part of the factory inlet off and weld back in what I need/design. Eaton says these blowers can be mounted in ANY position and operate just fine, so I'll probably lay it on its side, beside/above the motor.
- Remote mount would actually be easier to fab up because you can simply put a plenum w/ an outlet tube off the bottom of the blower and pipe it to the intercooler and the throttle body. Then the inlet is just ducting/filter. The biggest part of the remote mont would be the bracket(s) which shouldn't be too bad. I too plan on running it in with my factory serp belt so that I only have one belt, but w/ my set-up(remote or direct), it's very simple to position the blower for the belt with the factory snout/drive.

thanks for the replies, keep 'em comin...

justin

 

Well, based on the fact that I’ve wasted a good deal of my time working on my brother’s car:

(which runs high 10’s/low 11’s @120 on a 9”x26” tire in a 4 door LTD), you can imagine what my answer is (look at the picture)

 

83 Crossfire TA - pick didn't show.... - also remember, this is not being built for performance. SLT Suburban and fast don't go together....not even in the same paragraph.

 

Um, I don't know why, I'm on a different machine now with a different internet connection and I see it fine here also.

As far as performance/non performance application, for what it's worth, I've played on and off with building a simliar setup to bolt onto my TBI/350 (LO5) powered '92 K1500 blazer...

 

Strange. It shows up fine using Firefox. It shows up as a red X with MS internet explorer

 

- yeah, it shows at home, but didn't at work(dsl at home, roadrunner at work) who konws...

thanks for the pic and the reply. How does it drive? smooth power? - I'm thinking this is the way I'm gonna go, just wanting all the info/opinions that I can get.

also, did you run the factory bypass valve?

 

Huh, I usually use IE at home and it’s fine, seems fine in firefox also… any chance that the 2 machines are setup differently?

Runs and drives fine, the only drivability issues it has are the normal biggish cam/low compression deal. It gets mid 20’s on the highway…

Factory bypass? Sort of. It uses the stock housing, with a new butterfly (the stock one is setup so it always leaks some, there’s a notch cut out of it), welded to some of the ducting and actuated with a bike cable tied to the throttle linkage, you can see most of it here from behind the VC breather, this is a really old picture and a lot of what you see around it has changed:

 

doh! - I'll have to check at home, for some reason roadrunner must not like your pics....

sounds good. I think i'm gonna run it w/ the factory vac control and just put a dash-mounted mettering valve in the vac line so that I can control the boost. - speaking of which, anyone know where I can pick up the vaccum motor for the bypass? the blower I got was off a car that was in a fire....

 

Looks like my server is actually down this weekend, if it doesn't come back up by the end of sunday remind me (just post here and I'll get a reminder) and I'll post pictures somewhere else or find out exactly when it will be back up (a friend of mine runs the server)...

Motor... not sure, I've done a few aftermarket installs as well as the a few totally custom ones using stuff that has been pieced together. I know that the KB, Stillen and Mangussen setups that I did recently all have canisters so I would imagine that they all have them, I'm not sure how willing they will be to sell you one though. If you have problems finding one directly contact me off the board, preferably with a specific model, I should be able to get something through the shop or a friend of mine at eaton (don’t expect them to be cheap though, every time I’ve checked pricing on actual oem parts for these things I’ve decided that time+effort to make something or find something else that will work is usually less then buying the actual correct part).

FWIW, a lot of the newer and higher end setups are going cable operated (supposedly the Mercedes and jag M112 setups are both cable operated), so although they seem primitive they are becoming the preferred method. My brother also originally tried the bosch bypass valves like what come with the vortec, powerdine and ati kits and found that they weren’t sufficient to keep from blowing off the inlet ducting. I'm probably going to try using a Tial blowoff the nest time (it's like somethign over 50mm, I already have it sitting in the basement...)

 

If you side mount, intercool that sucker. Even some cheap SS auto chrome cooler offa evilbay is gonna help you out in this case. There's virtually no reason *not* to.

 

I don't know if you can see my original pic but if you're not fighting detonation then there is no reason to intercool... In that case I don't think that we car realistically expect the car to go any faster, it sees no detonation, and runs fine on 87 octane and the timing locked out at 33*

 

- I'm undecided on the intercooler. I'll probably run one, but I gonna have to do some more research on in. I don't want to go to big or I'll loose my boost. The cooler air charge should help for efficiency.
- I could probably do the cable bypass system, I just figured that for efficiency it'd be nice to be able to control the curve from the seat, and to change it for different driving conditions(freeway, city, towing, etc...) But, tuned right, the cable system would work, it'd just take some time to sort it out. - (fuel map vs bypass progression/rate)
- I was also thinking of the blow-off valve. Figured that way, no matter how I had the bypass set, I wouldn't make any more than....about 8psi.

 

As long as the intercooler is not a restriction, and it cools the air ... you will make more power even if detonation is not a problem without the intercooler.

 

I know, cooler air makes more power. As I said, I'll have to do some research. I'm more worrried about going big and loosing boost(psi) than I am small. I know myself well enough to know that I'd never buy some little rinky-dink thing that doens't flow enough.

 

Mark - on that cable bypass, is it just set-up 1:1? as in closed throttle = open bypass, WOT = closed bypass, or did you close the butterfly on a curve? I know you said you're running a solid butterfly, which is easily do able, just pondering the cable vs vaccum actuator set-up...

 

It's only fully closed at WOT... not like you really need to go fast otherwise anyway... for that matter, the car is probably a low 13s car, maybe faster without the blower so it's not that slow off boost either, and even with the part throttle leak you still get a very smooth power curve, if you didn't know it was there you wouldn't even wonder about it.

 

Cooler air does make more power if you don't have something forcing it in, but an intercooler is always going to restrict airflow some, and again, given a set mass of air and no detonation you'll make the same power anyway.

intercoolers buy you power when detonation limits the mass of air that you can force into the engine.

 

If you are happy with the power you are making and don't have any detonation, then you don't need the intercooler.

With an intercooler you will make the same power at lower boost because the air is more dense.

You will make more power if you stay at the same boost level with the intercooler. The engine will use more air mass if the air density is higer and VE is the same.

 

Only if you have excess flow capacity at the compressor and are detonation limited, and since that is not always the case then you won’t make more power. If you increase the air mass moved you will make more power, but an intercooler doesn’t always result in increased air mass. Same thing with water injection, it should cool the charge and result in denser air and more power but it doesn’t always. I actually have back to back runs with datalogs playing with this on an engine that was not detonation limited…

 

grr double post...

 

If the flow capacity at the compressor is the limiting factor then I agree, You will not make more peak power with an intercooler.

With the intercooler you should however still get more power at lower RPM when the compressor does not limit the flow.

 

I'm deffinitely going with the remote mount, but I'm still wanting to atleast try the vac. bypass. I think it'd be a better set-up for all around use because of different conditions(as previously stated, towing/town/higway/etc...)That way I can control the boost curve from the seat. I'm gonna run a blow-off to regulate max boost level and for decelaration. - I found the vac motor on ebay for like $75 shipped, thats probably as cheap as I'm gonna find one. - Being the GTP blower, my bypass is internal in the blower housing, but the controller is still external of course. If it doesn't work out the way I'm thinking, then I'll go the cable route.

- as for looking at intercoolers(still a possibility...if I need it) how do I find the right one? - Do they tell you the cfm it'll flow?

 

Don't use a BOV to control max boost ... That is not what it is made to do.

 

why not? I thought that a BOV was basically just a poppet that you set to "X" and it pops there, so why would this be an issue?
- what should I use?

maybe just a regular large capacity poppet...

 

Using a BOV to control boost is essentially wasting air. Compressing air raises the temperature of the air. Cooler air makes more horsepower. So having a higher boost than necessary will raise the temperature more and then you waste some of the air to keep the boost down. It would be better to lessen the boost and air temperature.
That is all theory. If you are only leaking enough air for dropping the boost 2PSI then it is probably easier to use the leak valve/BOV than buying/making a different pulley setup. I think the initial pully setup will be the hardest part to figure out unless you have them from the stock setup.

 

I realize that a BOV was built to dump excess air when you lift off the throttle. But I would think if it was dumping a little at WOT to regulate boost from time to time(remember, this isn't a hipo vehicle) it shouldn't care. I realize that I'd be over boosting to need this, but I just figured if I had my boost rate come in a little quicker when towing/screwing around that I should enable it to dump anything past "x" so as not to over-boost the motor. It shouldn't make much more than 8 psi, but just in case. - I'm gonna figure my % on the pullies and see where the blower rpm is at. I'm probably just gonna set it up to be right at eaton's suggested max at the motor's max rpm. I figured if I did it that way I could control the curve of the boost for different driving situations and just waste any extra psi at WOT.

I could run a poppet and dump it into the inlet duct...

- also, I'm figureing a 8psi max due to the stock-type internals(marine 305 flat-tops, GM "power forged" rods). I can vary the compression depending on the head gaskets I use, but a 305 w/ 64cc chamber heads is probably gonna be around 8.5-9:1 just thought 8psi would be about max safe boost level...

 

Yup, that is why I said that it is all theory. I would set it up like you planned and blow off extra air if need be. It doesn't seem worth it to play with pullies in an application like that.

 

Ok, this is not rocket science…

Intercooler: the positive displacement blower will pretty much flow what it does at whatever pulley ratio you have. If it doesn’t detonate without an intercooler you will not make more power with one, you will not make more power down low, or up top, you’ll make less by restricting airflow.

Bypass: figure out what you want to do and do it, that’s it. All it does is relieves the pressure when you let off the throttle to keep from blowing the ducting off. In the factory configuration and the way my brother did it it basically stays open unless you’re at WOT or close to it so you have NA style mpg and drivability till you need the extra power.

Boost control… change pulley sizes. If you need finer control then that then a slight restriction in the inlet would take care of it.

 

I know the proper way to regulate the boost would be pulley size, I was just planing on running it in w/ my factory serp belt, and the ratios are just about right for eatons suggested 12k max continous. - Just thought if I could make slightly more and dump it (when needed) I might be able to control the boost easier. I guess the first thing I'll have to know is how much boost it actually makes on the motor, and I won't know that until its together and running...

thanks for all the help guys!

 

again, don't dump it, restrict the intake, it will be easier and more effective.

 

gotcha - I guess I could easily build a sleeve that swould slip into the inlet duct before the TB, thus lowering the psi in the intake...makes sense. Then I could keep my variable boost rate idea but not waste the boost.
- like I said, I'll have to see what it makes before I get to worried. I would think if it flows 650 cfm ported then on a 305 only turning about 5k, it should make 8 or more. - Does my 8psi sound good as a safe limit?...maybe I should give it a little more/less?

 

Screw the sleave, just use a good sized throttle body...

 

- at 12-14k I probably won't see any more than 8psi anyway.

- that leads me to another question - I read many of the posts on this type of blower set-up and everyone says they're pretty loud. - Do you think I should put the TB in front of the blower instead of at the intake? Wouldn't be that hard to do, and it should help the noise and the make the factory bypass funtion easier...

 

search my previous posts about these things, you'll find some interesting info... I'll never retype all of it in one place anyway.

 

- yeah, I've been all over the search key on this one.
I want a little blower whine, it's there, so it might as well be noticed, but I don't want, as muscle mustangs said about your brother's, "...sounds like an F-14 Tomcat...". - found that article searching M90 info on google....
- so, I'm figuring I better put the TB in front of the blower. Should still make a good sound, especially at WOT, but hopefully not THAT loud.

 

Heh, people always think I'm bragging when I start listing the **** that I've built or built parts for that's ended up in magazine articles... at least in that one my brother actually gave me some credit/a thanks

Nutshell: the damend thing is loud (doesn’t help that he ran his intake into the heater box behind the glove box, so you practically have it sucking air in from between the passengers knees, not as exciting as it sounds), moves a lot more air then you expect it to and can be turned a lot faster then rated (this is both empirical knowledge, as in we’ve done it, and design knowledge, as in I know an eaton engineer). They actually get more efficient as you turn them faster till the heat from the extra boost causes the rotors to expand enough to contact (haven’t found that point yet).

FWIW, his is louder then most because we’ve heavily ported the inlet and outlet removing almost all the sound deadening features that didn’t make power. Again, I’ve posted tons about it on this board, but it’s probably 4 or more years old now…

Right now the car is being upgraded to an M112 with the TB in front of the blower (using a big cobra TB mounted basically where the strut tower is), so far I haven’t had much to do with this upgrade, and it hasn’t gotten too far either.

I’m hoping to snag the M90 for my truck.

 

how fast do you think(guesstimate) I should turn it to achieve 8psi on a mild 305? - Stock 3.736 bore w/ flat-tops(4-valve reliefs), ported vortec heads, ported TPI(all stock components), vortec cam(like 202/212, somwhere around 450 lift w/ 1.6s)

- I intend on porting the blower, but I'm a bit leary because I've heard the horror stories of over grinding and loosing power. I figure on slightly enlarging the "v" and chamferring the edge + the "silencer ports". as for the inlet, I'll just get all I can.

 

also, what size ducting would you reccomend? I'm thinking 3", but maybe 3.5-4?

 

Without actual numbers from what it is doing now it would be a guess, but I’d say around 14-16K rpm

There’s some power to be found in the outlet around the sinlencer stuff, but I wouldn’t change the general shape much there, there are some ridges to be cut out and some blending helps.

There’s a lot more power to be found in the inlet, there isn’t really enough metal around the bearings and the inlet boss for what can be done with good gains. Once you open it up blending it in to the inside of the case to feed the backs of the rotors will make a big difference.