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I'm not reading 100+ pages, anyone with cliffs?

Did he use MS with a M62 SC?
 

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Here's an interesting picture! It seems that this version of the 3.0 got a single knock sensor. Look at the adapter! Now...I know tht STOCK computers don't use this input, but what about aftermarket, or even a simple knock detector? Not everybody can bennefit from this, but I figured it was interesting...

Also, look at that ity bitty crossover tube for the coolant coming out the back of the water pump!

Brent...if you're looking, take a gander at his left valve cover...that large elbow in it looks to be PERFECT for the crankcase evac system you have!:thumb:

 

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Sucks for this guy...turns out he got a supercharger with a faulty bearing in it...the S/C nuked and due to all the metal produced from that carnage, probably took the engine with it. The engine ran, but there's no telling how bad the actual damage is without a tear-down.

Seems that the company that made the S/C is possibly offering to rebuild the unit...he's also seeing if they'll pay for parts to rebuild the engine since it was their product that caused the damage.

As a note he put down 121.4HP @ 4962rpms and 141.4TQ @ 4081rpms on a Mustang dyno with 32" tall tires and an auto with a tune that wasn't 100%. Boost was around 7#'s at redline.

His latest tune was yeilding around 20mpg on the highway on that brick! Not bad really! He thinks that the Diamante cams he has in it might be causing the engine to not take full advantage of the S/C due to the cams' design. I dunno...the few that have been done with our version have seemed to do pretty well...but I don't know really how our cam profile is compared to theirs.

Anyways...figured that was some fo the info that people might want without reading 101 pages of the origional thread. However, it IS very interesting and informative....:thumb:
 

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Here's an interesting picture! It seems that this version of the 3.0 got a single knock sensor. Look at the adapter! Now...I know tht STOCK computers don't use this input, but what about aftermarket, or even a simple knock detector? Not everybody can bennefit from this, but I figured it was interesting...
The knock sensor and adapter are from the 3.0 DOHC TT motor. I'm 99% sure the one sitting in my garage looks exactly like that. That is one of about 4 differences between the DOHC and SOHC blocks. The 3S service manual I got noted that there is a minor difference in 1 of the oil passageways, there are oil squirters that point at the underside of the pistons, and there are supposedly extra "reinforcements" built into the block. It doesn't say where and I threw out my old SOHC block to compare...:bang head
 

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I thought there were actual bosses the DOHC knock sensors went to...plus they used two IIRC. This one uses the bolt holes that are just in the valley(no actual bosses). I could have sworn I remember two in the one set of pictures I saw of a DOHC block...oh well...*shrugs*
 

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I thought there were actual bosses the DOHC knock sensors went to...plus they used two IIRC. This one uses the bolt holes that are just in the valley(no actual bosses). I could have sworn I remember two in the one set of pictures I saw of a DOHC block...oh well...*shrugs*
Uh, ya...my bad :eek:. There are bosses on the DOHC block. But there is only 1 knock sensor.
 

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I've read some of his thread, and when asked why he didn't go with a used m90 instead of a new m62, he said that the m90 wasn't sized right for his engine and that it was physically larger than the m62 (IIRC). Based on the specs given for the m62, it's nearly the same size as my m90. Anyone know about the output vs. engine size issue?
 

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Funny seeing this thread again. I'm a member of that forum as well. :D Raiders=fun
 

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I could have sworn that he said they sent him the wrong S/C to begin with....I thought we WANTED the M90, but ended up with the M62. Maybe I understood that wrong? *shrugs*
 

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I could have sworn that he said they sent him the wrong S/C to begin with....I thought we WANTED the M90, but ended up with the M62. Maybe I understood that wrong? *shrugs*
They sent him a M42 or whatever that is when he wanted the M62, Others did ask why didn't he go with a M90 but I forget the reason exactly why he didn't want to go with the M90
 

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The m62s out of the '90s Buicks were too long, whereas the new version (mp62) is more compact. It ends up being about the same size as an m90 out of a T-bird. His issue with the m90 was that it was sized wrong (displacement-wise, I think) for his motor. The m90 is intended for 3.0 to 5.0 motors, while the mp62 is sized for 2.0 to 4.0 mills. IIRC, he wanted the faster spool of the smaller displacement vs. the extra power.
 

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That's a misleading term, since boost is somewhat dependant on flow restriction. As an example, if you plug the exhaust, you can build a lot of boost in a hurry - even with a small blower. The better the engine flows air, the less the amount of apparent/indicated boost as measured by manifold pressure. One way to think of boost is available pressure to force air into the cylinders, but another way is to think of it as the amount of restriction to efficient air flow relative to the S/C output. That said, in everyday lingo, I'm looking for 6-8 lbs of boost which should be achievable with the MP62 on a 3.0L without heating the charge air too much. I've considered using an MP90, but I'd have to slow down the pumping rate by using a larger pulley if I want the engine to last - which would also slow down the onset of power. The trade-offs on blower maps are mind-boggling.

I'm not trying to build a race engine - just have a little more power without fear of blowing it to pieces. Maybe if this one works, I'll try an MP90 with mega boost later on a "built" engine.

Frank
Personally I'd still try to intercool the mp62 for even more dense intake charge :)
 

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As a note he put down 121.4HP @ 4962rpms and 141.4TQ @ 4081rpms on a Mustang dyno with 32" tall tires and an auto with a tune that wasn't 100%. Boost was around 7#'s at redline.
This doesn't seem very good. At 30% driveline losses, he's only cranking 175HP/200TQ. I don't know how much power a Montero puts out, but the Mitsler 3.0 was factory rated at 140/170 at the crank.

7# of boost seems like it should have more affect. :confused:
 

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that does seem off. on the non-boost friendly 24v i have , 8lbs of boost should have a net of ~300whp +- a bit. Im going to intercool my M90 for sure as keeping intake temps DOWN is one of the primary things in not blowing up my version of the 6g72
 

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"That said, in everyday lingo, I'm looking for 6-8 lbs of boost which should be achievable with the MP62 on a 3.0L without heating the charge air too much. I've considered using an MP90, but I'd have to slow down the pumping rate by using a larger pulley if I want the engine to last - which would also slow down the onset of power."

I'm new to SCs, so correct me if I'm wrong, but don't SCs have over-pressure (blow-off?)valves like turbos? So wouldn't I be better off having a large SC that can bring on X boost at a lower engine (and SC) speed to reduce heat, and then have a blow-off valve to dump the excess pressure created at higher engine speeds?
 

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I'm new to SCs, so correct me if I'm wrong, but don't SCs have over-pressure (blow-off?)valves like turbos? So wouldn't I be better off having a large SC that can bring on X boost at a lower engine (and SC) speed to reduce heat, and then have a blow-off valve to dump the excess pressure created at higher engine speeds?
You're thinking of centrifugal superchargers where a belt turns a compressor similar to a turbo. These design don't build boost until the engine is at a certain RPM and then vent any excess boost with a BOV.

An Eaton M62 or M90 is a positive displacement blower. An M90 theoretically moves 90ci of air with every revolution. You set the belt ratio up so that the M90 pumps more air per revolution then the engine would normally move - this creates boost in the motor. The faster an M90 turns compared to the Crankshaft the more air it moves per crankshaft revolution. This design has zero lag and full "boost" is available at any RPM. I say "boost" because these superchargers don't hold steady boost like a turbo. The PSI will rise and fall with the engine efficiency - ie boost will increase when the engine is in a an RPM where it doesn't flow as much air compared a "better flowing" rpm because the supercharger always move the same amount of air per revolution.

Better explanation than mine:
Centrifugal supercharging vs Positive Displacment superchargers
 
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