Question for those who know centri blowers...

[Wagonbacker9]

I know it wouldn't be called idea, but how effective is a FMU at tuning an otherwise stock engine with a blower added?

Looking at buying a truck that has a powerdyne blower, and it looks like the kit was installed with the FMU instead of retuning the PCM. I'm wondering how big of a risk it is that the engine is on its last legs. Its at 176K so anything is possible, but anyone who knows FMU tuning or centris better may be able to speak to it.

For reference, I'm looking at buying this partially because I have a trans with 67K on it, and a 5.3 I just put together with a boost friendly cam (228/222 114.5). Like any modified vehicle you run the risk of it being beat to shit regardless, I realize that, but it appears to be in good shape otherwise. Also, I really want to know who (besides me) puts a blower on a 4x4 ext cab truck, because I thought I was the only person on earth that though that sounded like fun.

Thoughts and input from the peanut gallery appreciated!

[Reverend Cooper]

First of all run.powerdyne is bullshit junk from personal exp. Do not get involved with any others their shit .fmu just cover the fact of lager pumps and injectors.it's not wrong but not the best way to do it.again don't bother with powerdyne junohk.

[Wagonbacker9]

Could you be more specific? What was/were the problem(s) you experienced?

I ask because I've seen issues with BD10 and BD11 units, but from what I've read the BD11a's (which this is) were much better. The BD10 had a tensioner that liked to break, and from what I've read the 11s bearings were upgraded for the 11a.

[Reverend Cooper]

Belt failure is imminent.bearings are junk.I literally had to get a lawyer after 6 failures to finally get their attention.they finally sent me their xb11 I think it was called a oiled gear drive set up.that one worked.I can only forwarn you.the belt drives are junk.

[Wagonbacker9]

6 failures over what kind of time/mileage?

xb-1a sound right?

[Reverend Cooper]

All were belt failure some bearings with belt failures the first one failed within ten minutes all six were in the same summer

[Reverend Cooper]

JI bet if I dug I could find the letter they were sent.also I still have some impeller bits here as well

[Wagonbacker9]

Looks like worst case is it eats a belt, I have to do a rebuild (which doesn't strike me as difficult, and I could fairly easily carry a stock length belt to bypass the blower. The xb-1a looks to be a direct replacement so I'll just keep my ear to the ground for one of those in the meantime.

I don't mean to ignore your good faith advice.. weighing pros and cons though...

[Reverend Cooper]

You don't need to bypass others if the belt breaks.you'll get sick of rebuilding it all the time belts aren't cheap nor are bearings.good luck.

[Reverend Cooper]

If I were you I would Google them and see all the complaints

[WI_Dave]

Is the truck a Black 99 3/4 ton? I only ask because if it is I may know some of the history on it.


EDIT: nevermind I think I found the one you talkin about.

[DRK]

I agree with Coop, total garbage. I had a XB11a in the late 90s it went in 3 times for bearings never had a belt break though. A lazy 800cfm max IIRC. The FMU just raises the fuel rail pressure with boost, the vortech discs work in it. I would put a WB on it if your worried. It probably doesn't need any retard with a belt driven "6psi" and enough premium fuel.

[WhatsADSM]

To be perfectly honest. FMUs suck and are hardly a good tuning tool. An FMU is only a very course way of "tuning" and does nothing in terms of tuning across rpm cells has ZERO effect on ignition timing not trimming based on temps, etc. I personally wouldn't even consider an FMU a tuning device.

However with that said I am also a realist. The truth is the stock computer on that vehicle is probably safe enough in terms of fueling and more importantly ignition timing (and knock control) that with a centri blower at low boost with premium gas everything is probably safe enough... not ideal but not bad enough to take itself apart. While the mileage is not a great indicator it seems that it backs up that theory if in fact the blower has been on there for a while.

[Wagonbacker9]

If I were you I would Google them and see all the complaints
I have.. it seems more people had issues with the vehicle than the blower, which I wouldn't blame the blower for.

Is the truck a Black 99 3/4 ton? I only ask because if it is I may know some of the history on it.


EDIT: nevermind I think I found the one you talkin about.
No, blue half ton, if you've looked on appleton's CL, you do.

I agree with Coop, total garbage. I had a XB11a in the late 90s it went in 3 times for bearings never had a belt break though. A lazy 800cfm max IIRC. The FMU just raises the fuel rail pressure with boost, the vortech discs work in it. I would put a WB on it if your worried. It probably doesn't need any retard with a belt driven "6psi" and enough premium fuel.
By then it'd be too late. I seriously doubt I could show up there say, "Yeah, could you put it up on a lift, I want to hook up my Innovate wideband for my test drive". LOL


To be perfectly honest. FMUs suck and are hardly a good tuning tool. An FMU is only a very course way of "tuning" and does nothing in terms of tuning across rpm cells has ZERO effect on ignition timing not trimming based on temps, etc. I personally wouldn't even consider an FMU a tuning device.

However with that said I am also a realist. The truth is the stock computer on that vehicle is probably safe enough in terms of fueling and more importantly ignition timing (and knock control) that with a centri blower at low boost with premium gas everything is probably safe enough... not ideal but not bad enough to take itself apart. While the mileage is not a great indicator it seems that it backs up that theory if in fact the blower has been on there for a while.
Having seen the tables of a similar GM PCM (in my GTO) this is what I was thinking. The only issue I would see is if the IAT is still pre-compressor then that may not be pulling timing appropriately, and I would assume that this was set up and run at relatively low boost.

Thanks all for your input.

[BR3W CITY]

It's been a while since I've seen FMU's used, most were on the older Honda and what not, stuff that really didn't have the capacity to tune in the ecm.

[Waver]

Dude, listen to coop. Everyone I know who has had them ended up getting rid of them/had them fail on them.......they are just made so cheap. Probably why they are the least expensive supercharger kit out there.

[Wagonbacker9]

I bought a procharger D1SC on ebay last night... upon inspecting the pictures I contacted the seller, turns out it was missing a bunch of shit, so we canceled the sale. Then I came to my senses and realized that I should really have the truck before I buy the blower. lol