No, I wish I had done a chassis dyno pull so I could see what the drivetrain losses were against OE specs enabling me to get a true increase after the S/C install - but after I swapped the transmission and had the top of the engine undressed, I was too lazy to put it back together to get a base-line.



With equal boost, you're covered for a Bud at 1/8 mile - that distance should favor the Roots blower. The turbo should gain on me after 3500rpms, though.

You don't mind if I swap to 28" tires, do you? <img src="/forums/images/graemlins/lol.gif" alt="" />

Frank

Some trial fitting for fuel supply and return lines. The pipes need to be shorter, but this combination of pipe and fittings will not require any boring of the plumbing parts:


The rear clearance issue was resolved (for one coolant tube) by removing 3/4" from the rear of the plenum box, which still allows enough room inside the box for the #6 runner opening. The rear stud will now be replaced by a socket screw inserted through the hole in the rear wall of the plenum - counter-bored to provide a flush fit for the top. The coolant supply line coming from the rear of the water pump will have to be slightly bent and one side of the fuel rail will need additional fittings to offset for clearance on the coolant supply tube:




Frank

Frank: You say you would like to achieve a 6-8 lb boost. What kind of mechanical compression will you be running?
Sweet project you have going there.kewl::
Conner

Terminal speed is so aptly named... <img src="/forums/images/graemlins/scared.gif" alt="" />

A few things to note on the turbine powered compressors (turbos). You can get boost at whatever RPM you would like by matching the turbo coreclty. So its possible to get signifigant boost well under 3500 rpm with a turbo.

The tiny hairdryer on mine spools up at about 2400 to 2600 rpm, by 2800 rpm I have 12 to 14 psi of boost pressure.

That will hold to redline.

Frank is correct its the mass air flow that matters, not just the pressure. Decrease the restricion in the motor and you can flow more air at a given pressure. The other factor is temperature, cooler is of course more dense.

8 psi at 280?f is a lot less effective than 8 psi at 180?f.

Thats the fun of an intercooler....The faster you go the denser your charge since it will cool better. As far as response goes it will be very interesting to see the combo off a TPI with a blower, of idle should be great.

My system is at the opposite end of the spectrum, TBI and a turbo. It takes a tiny bit of time to respond from a standstill, almost a second, or about 1/2 way across an intersection, on a roll its instantanious.

Someday I will get a TPI setup for mine.

Looks good!

Kevin

Not at all. I'll be on lowrider rims myself, and in lo range (woops, didn't mean to mention that one....), with a fresh haha bottle in the back, with a hydrogen peroxide rocket socked into the receiver hitch.....

Frank, why not buy one of those smaller roots type eaton units off of Ebay, and stick that on there? ALOT cheaper initially, and replacment. I would think thet are matched sufficiently to a 3.0..... They were used on the FWD 3.8's and 3.0 GM engines. GTP pontiacs and such.

Kick ass on the project anyway!!!! I am glad to see someone that is doing something different, and difficult, and not moaning about "WANWANH lack of aftermarket support" that we so often hear.

GJ! <img src="/forums/images/graemlins/kewl.gif" alt="" /> <img src="/forums/images/graemlins/kewl.gif" alt="" />

Conner, I haven't changed the stock 8.9:1 compression ratio other than the slight (0.50mm/.020") overbore and head/deck surfacing when I did the engine rebuild. It's just right for modest boost and the 3.0L ignition curve under acceleration seems to beg for a blower - advance drops to 15* BTDC under load. If the boost shows ~10psi (and it might), I won't mind since I "think" I have enough leeway with fuel pressure and injectors to tune it.

I'm not trying to build a race engine - just trying to gain some mid-upper range carry on the hills in O/D and 3rd with 32" tires without lugging.... should be doable.... the off-idle "right now" power Kevin referred to is the kicker that I'll hopefully get to enjoy daily as I leave the stoplights. <img src="/forums/images/graemlins/wink.gif" alt="" />

Kevin, I've allowed for an aftercooler, but probably won't install it unless/until I need it. If I get any detonation - or if boost is above 8psi - I'll install it. It's just a matter of cutting another S/C mounting plate with an extended flange to accept the heat extractor/exchanger, adding a coolant pump and installing a remote heat exchanger under the front skid plate. The compressor maps show ~80F(dT) above ambient at max, so 180-220F should be peak, with the lower value at modest boost and short duty cycles (ooops - looked again at the Eaton chart supplied by Magnacharger and it shows 180F(dT), but a Magnacharger rep says they see 220F discharge temps on the MP62 ... I "thought".. before cooling... I need to check that again). As you know, the trade off in cooling is air flow restriction... I'd like to run it first without the aftercooler to see what happens.

This is the first forced induction engine package I've built, so I'm taking it one step at a time. If this one works, I might go all out on the next one - this one I want to be very street-friendly with no drivability issues - and I want it to be as simple and reliable as possible.

Frank

Curtis -

Those units would be great - they're M62s - same as what I'm using, but the arse end of them is too long - won't fit in the available space. Here's a picture of one:

For comparison, look at how simple the design of the Magnacharger housing casting is for inlet port attachment (you can click on the drawings for enlarged view):
MP62

I also tried an Xterra MP62, but the overall casting was a little too long - plus the inlet port was on the wrong side. Here's a Nissan unit I bought on ebay, decided it wasn't the best choice and sold it for a small profit <img src="/forums/images/graemlins/wink.gif" alt="" />:


The only cheapo unit that will work is a 3rd Gen M90 as found on T-Birds, but unless you want mega boost, it's too big. You can slow it down, but then you get lag off idle.The really critical part of this is the overall length of the unit and the lack of space in which to install it. The transverse mounted engines have it easy because of available space side-to-side in the engine bay. Here's one example - you can see what I mean:


The length of the nose drive is highly critical if the inlet piping is kept within reasonable shapes. As an example, I want to use 90* elbows to make the inlet turn at the rear of the unit instead of a square box. A box inlet saves space, but I'd think the square corners would inhibit good air flow somewhat. In order to use the elbow inlet, the nose drive must be shorter. All of a sudden, you start running out of fore'n'aft space. None of the available M62 blowers have a stock nose drive in a length that will work. By the time I buy a custom replacement nose drive in the right length, I've spent a lot of money and still would have a used blower with maybe questionable bearings and rotors that would need to be rebuilt for reliability and best performance.

I'd like to (and can) build it on the cheap, but I don't think it's necessarily the best way for what I want out of it.

Frank

Once again Frank..... Sounds like you have done your homework. lemme know if you are on the lookout for anythign in particular. I have some "in's" at a few salvage yards.

With nothing to do until the S/C shell arrives, I decided to try-fit the plenum mock-up in the engine bay. The plenum will be reduced in width - plus some length hopefully taken off the front - but you can see how tight the fit is against the firewall:

Future trimming on the driver side of the plenum will resolve the heater hose interference issue:

This project might be worthwhile just to have easy access to the PCV valve <img src="/forums/images/graemlins/lol.gif" alt="" />:

Checking here for hood clearance:

......it looks like a hood scoop is definitely in my future. <img src="/forums/images/graemlins/baby.gif" alt="" /> <img src="/forums/images/graemlins/wink.gif" alt="" /> <img src="/forums/images/graemlins/notooth.gif" alt="" /> <img src="/forums/images/graemlins/butwiggle.gif" alt="" /> <img src="/forums/images/graemlins/evil.gif" alt="" /> <img src="/forums/images/graemlins/kewl.gif" alt="" />

Frank