Powerdyne alternator relocation question
Thread Starter
Safety Car
Joined: May 2006
Posts: 4,290
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From: Salem NH
Powerdyne alternator relocation question
I'm buying a powerdyne install kit from supernatural tonight. Gonna pick up a BD-11A eventually (in the next week or too, assuming it snows and I get some plow money).
I have my AC deleted. So I have a big pulley sitting where my ac compressor used to be. Any reason you folks can think of, as to why I couldn't just relocate the alternator to where the AC compressor was?
I don't like this idea of spinning it backwards.
I've had a few vortechs on my last car. I know the powerdyne will only put out like 6-8psi. My compression ratio is 10:1 as it is with aluminum heads, so I can't run a whole lot of boost anyway.
-- Joe
I have my AC deleted. So I have a big pulley sitting where my ac compressor used to be. Any reason you folks can think of, as to why I couldn't just relocate the alternator to where the AC compressor was?
I don't like this idea of spinning it backwards.
I've had a few vortechs on my last car. I know the powerdyne will only put out like 6-8psi. My compression ratio is 10:1 as it is with aluminum heads, so I can't run a whole lot of boost anyway.
-- Joe
Burning Brakes
Joined: Sep 2006
Posts: 1,142
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From: Spring Grove Illinois
I'm not sure how that would work with Powerdyne's solid tensioner...I'm looking at pics of mine (it's off now...Mod time
) and unless you make a movable tensioner kinda like prochargers or vortec's it might be a challange..Belt slippage
...I didn't (or wont) have an issue with the design got 8lbs boost consistently and trouble free...JMO
) and unless you make a movable tensioner kinda like prochargers or vortec's it might be a challange..Belt slippage ...I didn't (or wont) have an issue with the design got 8lbs boost consistently and trouble free...JMO
Thread Starter
Safety Car
Joined: May 2006
Posts: 4,290
Likes: 140
From: Salem NH
I'm not sure how that would work with Powerdyne's solid tensioner...I'm looking at pics of mine (it's off now...Mod time ) and unless you make a movable tensioner kinda like prochargers or vortec's it might be a challange..Belt slippage ...I didn't (or wont) have an issue with the design got 8lbs boost consistently and trouble free...JMO
) and unless you make a movable tensioner kinda like prochargers or vortec's it might be a challange..Belt slippage ...I didn't (or wont) have an issue with the design got 8lbs boost consistently and trouble free...JMOI'm not planning on removing the bracket for the AC compressor, just making an adapter to mount the alternator in it's place..
-- Joe
Thread Starter
Safety Car
Joined: May 2006
Posts: 4,290
Likes: 140
From: Salem NH
Advanced
Joined: Sep 2004
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I would re think the powerdyne.
I've been running one for a few years now and had good results until I installed a better intake and heads and now can rev a little higher. I had more problems with bearings and belts in that damn powerdyne. I tried a bunch of different vendors, ceramic bearings, kevlar belts, they still have problems.
I am planning on switching to a procharger or vortech. It just is not a reliable supercharger. I spent more on rebuilds then if I bought a gear driven supercharger.
I've been running one for a few years now and had good results until I installed a better intake and heads and now can rev a little higher. I had more problems with bearings and belts in that damn powerdyne. I tried a bunch of different vendors, ceramic bearings, kevlar belts, they still have problems.
I am planning on switching to a procharger or vortech. It just is not a reliable supercharger. I spent more on rebuilds then if I bought a gear driven supercharger.
Thread Starter
Safety Car
Joined: May 2006
Posts: 4,290
Likes: 140
From: Salem NH
I would re think the powerdyne.
I've been running one for a few years now and had good results until I installed a better intake and heads and now can rev a little higher. I had more problems with bearings and belts in that damn powerdyne. I tried a bunch of different vendors, ceramic bearings, kevlar belts, they still have problems.
I am planning on switching to a procharger or vortech. It just is not a reliable supercharger. I spent more on rebuilds then if I bought a gear driven supercharger.
I've been running one for a few years now and had good results until I installed a better intake and heads and now can rev a little higher. I had more problems with bearings and belts in that damn powerdyne. I tried a bunch of different vendors, ceramic bearings, kevlar belts, they still have problems.
I am planning on switching to a procharger or vortech. It just is not a reliable supercharger. I spent more on rebuilds then if I bought a gear driven supercharger.
The powerdyne is the best scenario for my setup. I'm at 10.4:1 compression, so I can really only run about 6psi boost. I can run a 3.33 pully which puts me well under the safety zone of impeller speed.
If I was running a 9:1 setup, id agree a gear driven charger and 10-12psi would be in order. but at my compression ratio, the supercharger simply compliments the setup.
-- Joe
Melting Slicks
Joined: Aug 2003
Posts: 3,409
Likes: 400
From: Lakeville MI
I would re think the powerdyne.
I've been running one for a few years now and had good results until I installed a better intake and heads and now can rev a little higher. I had more problems with bearings and belts in that damn powerdyne. I tried a bunch of different vendors, ceramic bearings, kevlar belts, they still have problems.
I've been running one for a few years now and had good results until I installed a better intake and heads and now can rev a little higher. I had more problems with bearings and belts in that damn powerdyne. I tried a bunch of different vendors, ceramic bearings, kevlar belts, they still have problems.
Can you provide your crank and blower pulley diameters and also your max engine rpm?
At present I'm running an underdrive crank pulley (5.75 or 6" diameter I think, I don't have an exact measurement) and 2.93" blower pulley, which results in about 36,000 impeller rpm @ 6,000 engine rpm. This should be relatively safe, according to the rebuilders.
A stock 7" crank pulley and 2.93" blower pulley could cause problems above 5,000-5,500 rpm. If running a stock crank pulley, you may want to back off on the blower pulley to a 3.12" or even larger.
I also picked up a spare head unit, just in case.
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Thread Starter
Safety Car
Joined: May 2006
Posts: 4,290
Likes: 140
From: Salem NH
I'm curious how fast you are spinning the impeller? Over 36,000 rpm?
Can you provide your crank and blower pulley diameters and also your max engine rpm?
At present I'm running an underdrive crank pulley (5.75 or 6" diameter I think, I don't have an exact measurement) and 2.93" blower pulley, which results in about 36,000 impeller rpm @ 6,000 engine rpm. This should be relatively safe, according to the rebuilders.
A stock 7" crank pulley and 2.93" blower pulley could cause problems above 5,000-5,500 rpm. If running a stock crank pulley, you may want to back off on the blower pulley to a 3.12" or even larger.
Can you provide your crank and blower pulley diameters and also your max engine rpm?
At present I'm running an underdrive crank pulley (5.75 or 6" diameter I think, I don't have an exact measurement) and 2.93" blower pulley, which results in about 36,000 impeller rpm @ 6,000 engine rpm. This should be relatively safe, according to the rebuilders.
A stock 7" crank pulley and 2.93" blower pulley could cause problems above 5,000-5,500 rpm. If running a stock crank pulley, you may want to back off on the blower pulley to a 3.12" or even larger.
I figured a 7" crank pulley and 3.33 blower pulley puts me safe till about 6200 RPM. With a 6k shift, and 6200 rev limit that should be safe I'd think.
-- Joe
Melting Slicks
Joined: Aug 2003
Posts: 3,409
Likes: 400
From: Lakeville MI
Step-up is 3.05:1 like a P600B.
3.33" with a 7" crank would be 39,750 @ 6200 rpm or about 38,468 @ 6000. Should be ok for short bursts up there.
That combo would only run about 1,000 rpm higher than a 6 lb. LT1 set-up with 6" crank and 2.93" blower pulley. Sounds reasonable.
3.33" with a 7" crank would be 39,750 @ 6200 rpm or about 38,468 @ 6000. Should be ok for short bursts up there.
That combo would only run about 1,000 rpm higher than a 6 lb. LT1 set-up with 6" crank and 2.93" blower pulley. Sounds reasonable.
Last edited by tequilaboy; Feb 7, 2008 at 12:46 PM.
Thread Starter
Safety Car
Joined: May 2006
Posts: 4,290
Likes: 140
From: Salem NH
Hrmm.. 38,468 rpm with a 3.33 pulley then. Limit is 41,000 with a BD-11A, correct?
Hah. I saw your edits after I posted this.
Found this on a SVT site:
Max Blower Impeller Speed 42500 RPM
Max Efficient Impeller Speed 40600 RPM
So it seems, the 3.33 pully is idea for a 6,000 RPM shift. Keeps it both under the max and within
the efficient range. Whats the efficiency of a BD-11A anyhow? (for simulation purposes). I can't seem to find
a compressor map. Most folks compare it to an A-trim, which is about 65%.
The more I read the more I like this blower. It would absolutely suck on a bigger engine or a lower compression (blower motor) but
for a average stock engine, or higher compression it's better than nitrous. Probably good for 100hp increase at 6psi..
-- Joe
Hah. I saw your edits after I posted this.
Found this on a SVT site:
Max Blower Impeller Speed 42500 RPM
Max Efficient Impeller Speed 40600 RPM
So it seems, the 3.33 pully is idea for a 6,000 RPM shift. Keeps it both under the max and within
the efficient range. Whats the efficiency of a BD-11A anyhow? (for simulation purposes). I can't seem to find
a compressor map. Most folks compare it to an A-trim, which is about 65%.
The more I read the more I like this blower. It would absolutely suck on a bigger engine or a lower compression (blower motor) but
for a average stock engine, or higher compression it's better than nitrous. Probably good for 100hp increase at 6psi..
-- Joe
Last edited by anesthes; Feb 7, 2008 at 12:51 PM.
Advanced
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I'm running a 2.83 pulley on the blower, 7" crank, 3.05 internal.
Overall ratio = 7.544
5500 rpm x 7.544 = 41492 rpm
A little high, but how long am I there.
I won't lower boost, I would really like a little more since I have water injection.
I like the Vortech SC blower, as quiet and more reliable.
Overall ratio = 7.544
5500 rpm x 7.544 = 41492 rpm
A little high, but how long am I there.
I won't lower boost, I would really like a little more since I have water injection.
I like the Vortech SC blower, as quiet and more reliable.
Melting Slicks
Joined: Aug 2003
Posts: 3,409
Likes: 400
From: Lakeville MI
I haven't been able to find a compressor map. Here are a couple examples of boost vs rpm, so you can get an idea of the linearity.
I did find this boost comparison chart:
http://www.kennebell.net/techinfo/fo...boltonVSsc.pdf
It would be nice to see the whole article to see which blowers are being compared, but I haven't found it yet.
and also this (note the boost curve in yellow on the colored dyno pull):
http://forums.beyond.ca/showthread/t-14757.html
I did find this boost comparison chart:
http://www.kennebell.net/techinfo/fo...boltonVSsc.pdf
It would be nice to see the whole article to see which blowers are being compared, but I haven't found it yet.
and also this (note the boost curve in yellow on the colored dyno pull):
http://forums.beyond.ca/showthread/t-14757.html
Thread Starter
Safety Car
Joined: May 2006
Posts: 4,290
Likes: 140
From: Salem NH
I'm running a 2.83 pulley on the blower, 7" crank, 3.05 internal.
Overall ratio = 7.544
5500 rpm x 7.544 = 41492 rpm
A little high, but how long am I there.
I won't lower boost, I would really like a little more since I have water injection.
I like the Vortech SC blower, as quiet and more reliable.
Overall ratio = 7.544
5500 rpm x 7.544 = 41492 rpm
A little high, but how long am I there.
I won't lower boost, I would really like a little more since I have water injection.
I like the Vortech SC blower, as quiet and more reliable.
Here is my old setup:
http://members.cisdi.com/~anesthes/intake-8-27.jpg
Just too much noise. I had an SC trim though. The SQ is more quiet because of the gears are cut at an angle.
-- Joe
Thread Starter
Safety Car
Joined: May 2006
Posts: 4,290
Likes: 140
From: Salem NH
You guys check out the ceramic bearings that are good for up to 60k? And the new impeller designs by 928 motorsports? The flow charts are pretty impressive.
The more I read into it, the more benefits I see.
-- Joe
The more I read into it, the more benefits I see.
-- Joe
Thread Starter
Safety Car
Joined: May 2006
Posts: 4,290
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From: Salem NH
Well the alternator will mount in the a/c compressor bracket and belt lines up fine.
This is good, because if a belt breaks or throws it won't require alternator removal to change it,and the alternator shouldn't burn out.
-- Joe
This is good, because if a belt breaks or throws it won't require alternator removal to change it,and the alternator shouldn't burn out.
-- Joe
Thread Starter
Safety Car
Joined: May 2006
Posts: 4,290
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From: Salem NH
almost done. Alt on other side, blower mounted. Need to add a second
idler, connect a few things, etc.
I have a FMU inline but disconnected. If the 2-bar sy-ty stuff starts pissing me off again, I'll go back to 1-bar $8d and run the FMU for fuel.
-- Joe
idler, connect a few things, etc.
I have a FMU inline but disconnected. If the 2-bar sy-ty stuff starts pissing me off again, I'll go back to 1-bar $8d and run the FMU for fuel.
-- Joe
Last edited by anesthes; Apr 8, 2008 at 09:26 PM.
Thread Starter
Safety Car
Joined: May 2006
Posts: 4,290
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From: Salem NH
Blower setup is done. Piping off so I can set timing and what not. I also need to trim the cable bracket on the miniram
so the plumbing clears it and the hood closes. Hood prop almost done. I gotta bleed the clutch.
Honestly, if you guys don't have AC I recommend routing like I did. Lots of room up front, don't have to relocate the PS resovoir, or run a different upper radiator hose.
-- Joe
so the plumbing clears it and the hood closes. Hood prop almost done. I gotta bleed the clutch.
Honestly, if you guys don't have AC I recommend routing like I did. Lots of room up front, don't have to relocate the PS resovoir, or run a different upper radiator hose.
-- Joe
Melting Slicks
Joined: Aug 2003
Posts: 3,409
Likes: 400
From: Lakeville MI
Its getting there. Looks good.
If I ever ditch the A/C, I'd be tempted to stick another blower on the passenger side.
What's with the small black plate between the blower and pulley, something to keep the belt off of the fins or is it just a weird shadow?
If I ever ditch the A/C, I'd be tempted to stick another blower on the passenger side.
What's with the small black plate between the blower and pulley, something to keep the belt off of the fins or is it just a weird shadow?