Opinions: S-port rebuild or replace?

RichM

Registered User
My Magnuson S-port is in need of a rebuild. I am wondering if I should just go with a Magnum Powers MPII or have the S-port rebuilt?

My understanding this that the S-port and the MPII are comparable, not exact but close.

If I go with the rebuild who's recommended? Magnuson? Supercoupe Performance (Magnum Powers)? MagnaCharger (through superchargersonline.com)? Canadian Supercharger? The High Speed Lab? PSE (through superchargersonline.com)? Did I miss anyone?

I like the idea of spending less to rebuild the S-port. But, I also like the idea of the MPII matching the MP plenum better and possibly picking up some HP for only a few hundred more than the rebuild cost. But, I'm worried about possible changes to the tune (note to XR7Dave if you read this, I have the logs and will try to download them from the computer and e-mail them out to you tonight).

I would like to resist the temptation of going with the MPIII or an AR because of the added expense and/or work involved. The car is a daily driver so reliability is very high on the list of requirements.

I originally bought the S-port back in 1995 and put over 130,000 miles on it before it started to rattle.
 
you can very easily do a snout rebuild, rear rotor bearings, and solid coupler for about $100. If you have a rattle you could just replace the coupler for about $30. They are very easy to rebuild and I think there are detailed instructions in the FAQ forum.
 
I think the rebuild is cheap enough and the S port a good enough blower that you would be fine going that route. Spend the money saved on an MP inlet and TB and other stuff..My opinion:O)
 
rzimmerl said:
you can very easily do a snout rebuild, rear rotor bearings, and solid coupler for about $100. If you have a rattle you could just replace the coupler for about $30. They are very easy to rebuild and I think there are detailed instructions in the FAQ forum.

I've already got a replacement coupler, but with the 130,000+ miles on the blower I'd like to either replace it or get a full rebuild. Oh and I don't have a press for installing the bearings. Not to mention the time.

DamonSlowpokeBaumann said:
I think the rebuild is cheap enough and the S port a good enough blower that you would be fine going that route. Spend the money saved on an MP inlet and TB and other stuff. My opinion:O)

Damon, I already have the MP inlet, larger TB and other stuff (check the sig). Actually the only other modifications that I have even considered are roller rockers, a front mount and possibly going from the S-port to the MPII. But I've only considered it. Once I get the tune done I really had no "plans" to do anymore upgrades to the motor. Then that whole "unplanned upgrade" thing happens.

I am leaning towards just having the blower rebuilt, But who has the best reputation for quality blower rebuilds?
Anyone can beat a new set of bearings in with a hammer, but I'd really like this thing to last another 100k+ miles. Reliability is the prime reason I'm not overdriving the blower
 
I woudl think anyone that rebuilds these can do a good job as it isnt that hard to do. keep in mind the MPIII and MPII are basically rebuild and modified 89-93 blowers...WHich also means youde need a core.

I think you can reliably OD the blower 5% via a jackshaft and loose some rotating mass as well going to aluminum..Also a set of Aluminum UD pulleys would be a great addition.....Maybe even a 76mm MAF for that 75mm TB.

Only probalem I see going with a front mount being you are into reliability is that yoru SC will not work nearly as well and the car will tend to run hotter.
 
DamonSlowpokeBaumann said:
MP inlet for SC you have..Wasnt specific...??

Ok, fixed the sig. Sorry I wasn't specific.

I haven't been able to find a listing for a 5% OD jackshaft pulley, all I have seen are the 10% jackshaft pulleys. Where does one find such a pulley?

Underdrives are out of the question, I run to many electronic devices when I road trip and the temps have been hitting 100+ for the last few days. Scary since where I live usually doesn't get that hot until July. Going to be a very hot year.

BTW, Thanks Damon
 
I would rebuild the "S" port. If you don't already have one, get an MP inlet plenum and install a 5% overdriven jackshaft pulley while you have it apart.

Of the places you listed, Magum Powers would probably be the fastest and most economical.

David

PS: I think SCP sells the 5% JS pulley.
 
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I would not run an OD pulley on an S-Port on a stock motor and if you are already worried about cooling don't consider a FMIC. For a rebuild on the blower I'd send it back to Magnusen. It only makes sense to do it right.
 
Get a price from Magnasun..They tend to be...Expensive and I dont see them doing anything extra ordinary during the rebuild process to quantify the added cost.

SCP or Spinning Wheels has a 5% jackshaft for sale. Dave D had run an Sport for some time I believe without an OD on the jackshaft. I personally dont feel the extra 5% on a basically stock motor shouldnt be an issue being teh blower wont be spun fast enough to cause any isues . Being stock motors rev no more then 5000-5,500 (depending on the factory tach) effectively.

I still think Id go with the 76mm MAF:O)
 
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I think I've owned an SC too long. One of my belts started shreading so I changed the belt, lower radiator hose and swapped coolant. Stared the motor and finally figued out what my strange engine sounds was coming from. Sounds like the IAC is going bad. Looks like I have some more time on that blower.

update, way wrong on the IAC. disconnected the IAC and reset the blead screw and still had the sound. I need my hearing checked. I called Magnuson and left a message, hopefully they will get back with me.
 
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Rebuild

I got the next-to-last MP II. They only had one more rear plate, when I bought mine, last summer. At that time, they had no intention of continueing MPII's. If you want an MP II, you'd better contact Charles ASAP. Unless you want to spend the bucks for the MP III (plus required inlet plenum!!!), Just get your blower rebuilt. That's the cheapest thing to do, since you already have a MP inlet plenum.

68COUGAR
 
DamonSlowpokeBaumann said:
Get a price from Magnasun..They tend to be...Expensive and I dont see them doing anything extra ordinary during the rebuild process to quantify the added cost.

SCP or Spinning Wheels has a 5% jackshaft for sale. Dave D had run an Sport for some time I believe without an OD on the jackshaft. I personally dont feel the extra 5% on a basically stock motor shouldnt be an issue being teh blower wont be spun fast enough to cause any isues . Being stock motors rev no more then 5000-5,500 (depending on the factory tach) effectively.

I still think Id go with the 76mm MAF:O)

Magnuson does a much more thorough job at remanufactoring the sc.About the only parts reused are the supercharger nose,case ,and bypass valve.
 
68COUGAR said:
I got the next-to-last MP II. They only had one more rear plate, when I bought mine, last summer. At that time, they had no intention of continueing MPII's. If you want an MP II, you'd better contact Charles ASAP. Unless you want to spend the bucks for the MP III (plus required inlet plenum!!!), Just get your blower rebuilt. That's the cheapest thing to do, since you already have a MP inlet plenum.

68COUGAR

Too late.I talked to him yesterday.MPIIs are history.
 
I had originally decided to go with Magnuson for a rebuild. But after three weeks of trying to get a hold of "David" to get an estimate I'm contemplating other options.

The blower isn't rattling as much as making a high pitch whine at idle and during engine deceleration. While the blower is accelerating there is no discernable whine. So I think the coupler is ok but one of the bearings is going out. The sound is really noticeable when I shut the motor off, listening to that almost makes me want to cry.
 
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