varanus
Enthusiast
Ditto above on HP
Now Taking Orders For The Viper Supercharger System...
- Thread starter Sean Roe
- Start date
Regarding the HP increase, I'd rather wait and post the actual numbers than speculate. But, the power will go up.
Edit- Power increased 30 RWHP with the redesign.
On the smooth tubes, I prefer the clean look once installed, but wanted some sort of identification on them. So, the logo is on the bottom.
Sean
<FONT COLOR="#ff0000" SIZE="1" FACE="Verdana, Arial">This message has been edited by Sean Roe on 07-17-2002 at 05:05 PM</font>
Edit- Power increased 30 RWHP with the redesign.
On the smooth tubes, I prefer the clean look once installed, but wanted some sort of identification on them. So, the logo is on the bottom.
Sean
<FONT COLOR="#ff0000" SIZE="1" FACE="Verdana, Arial">This message has been edited by Sean Roe on 07-17-2002 at 05:05 PM</font>
varanus
Enthusiast
<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Sean Roe:
Regarding the HP increase, I'd rather wait and post the actual numbers than speculate. But, the power will go up.
On the smooth tubes, I prefer the clean look once installed, but wanted some sort of identification on them. So, the logo is on the bottom.
Sean<HR></BLOCKQUOTE>
Ooooo like maybe 200 rwhp?
Oops, sorry, just dreaming
Can't wait to hear. When do you think you will get some figures Sean?
Regarding the HP increase, I'd rather wait and post the actual numbers than speculate. But, the power will go up.
On the smooth tubes, I prefer the clean look once installed, but wanted some sort of identification on them. So, the logo is on the bottom.
Sean<HR></BLOCKQUOTE>
Ooooo like maybe 200 rwhp?
Oops, sorry, just dreaming
Can't wait to hear. When do you think you will get some figures Sean?
VPRVENM97
Enthusiast
<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by varanus:
Ooooo like maybe 200 rwhp?
Oops, sorry, just dreaming
Can't wait to hear. When do you think you will get some figures Sean?
<HR></BLOCKQUOTE>
Sean,
Can you tell Kevin is reeeeaaaallllly anxious? Me too.
Looking forward to the results.
Ooooo like maybe 200 rwhp?
Oops, sorry, just dreaming
Can't wait to hear. When do you think you will get some figures Sean?
<HR></BLOCKQUOTE>
Sean,
Can you tell Kevin is reeeeaaaallllly anxious? Me too.
varanus
Enthusiast
Anxious?
That's an understatement!
I think about this thing on a daily basis
I am sick for power and this is the cure!
That's an understatement!
I think about this thing on a daily basis
I am sick for power and this is the cure!
We'll post the next dyno results when all components are in their production *as we will deliver to you* form. It will be a couple weeks. We have planned for everything to come together at about the same time.
Sean
Sean
Bugeater
Enthusiast
Typically when you make it easier to breathe (in your case exhaust) on a forced-induction motor the benefits are magnified. Same as on the intake side.
Bugs is right on target.
To that end, we're going to test a set of 1&3/4" headers at some point to see how it reacts.
To that end, we're going to test a set of 1&3/4" headers at some point to see how it reacts.
jk
Enthusiast
I was considering adding headers this summer, but with your package do you see the headers providing much of a change with the S/C kit? In other words, would the S/C kit HP output be much different if I did or didn't have headers installed? I have heard it mentioned that in a forced air system the headers will not make as much of a difference, especially in the some model years of the Viper. (Mine is a 2000).
Thanks,
Jim
Thanks,
Jim
VENM8R
Viper Owner
Couldn't a cooler be placed between the supercharger and intake thus lowering the air temp. enough to enable it to safely boost at 9 or 10 psi? or does hood clearance play into this?
David
Viper Owner
Roe's supercharger places the compressor behind the throttle bodies. This is important as most driving is performed with the intake manifold at 1/4 atmospheric pressure (partial vacuum). Since the compressor is primarily spinning in a vacuum, this results in very little heat buildup. When you stomp on the pedal, the intake manifold comes up to atmospheric pressure and the supercharger will then boost it to +5 or +6 PSI. Under those conditions, you will get heating -- but less than a centrifugal compressor as the Opcon is more efficient. Most superchargers are placed in front of the throttle bodies, which results in the compressor spinning at full atmospheric pressure. This results in a lot of heating or "cooking" of the intake charge as the air is backed up against the throttle bodies. Blow-off valves are only a partial solution. Even with a vacuum dashpot, there's still some positive pressure trapped between the compressor and the throttle bodies. As far as I know, Roe's supercharger is currently the only one which places it's compressor behind the throttle bodies. This is a more optimal placement.
VPRVENM97
Enthusiast
<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by David:
As far as I know, Roe's supercharger is currently the only one which places it's compressor behind the throttle bodies. This is a more optimal placement.
<HR></BLOCKQUOTE>
.....and that is why I want a Sean Roe Supercharger. Plus I've heard nothing but good comments about Sean.
As far as I know, Roe's supercharger is currently the only one which places it's compressor behind the throttle bodies. This is a more optimal placement.
<HR></BLOCKQUOTE>
.....and that is why I want a Sean Roe Supercharger. Plus I've heard nothing but good comments about Sean.
varanus
Enthusiast
I did some research tonight in comparing centrifical (the $3,100 type) versus the screw type Sean is using. Some of it went over my head, but from what I gathered
the centrifical has more power potential in the end if all other factors such as engine integrety, fuel, etc is taken care of. It is also least parasitic. But power comes on at the upper end of rpm-kind of like when turbos spool up. So it's a little peakier. If you are after pure top end power this is the way to go.
The opcon screw is very linear in that the power increase is much more in line with engine rpm increase. After about 5500 rpm or so I think it may be maxed out. But if you are road racing or street racing where you are often in the 2000 to 4000 rpm it may be a better choice for overall drivability. For my style of driving and intent, Sean's is the way to go for me unless I see claims that the $3,100 centrifigal that make it obvious it's the better choice (besides price)
I know Sean has spent a lot of time working on it to make it right and has posted for quite a while on it. This $3,100 just popped up, so I don't really know much about it. Of course the price seemed awfully good, so I had to at least see what the diference was between the 2 types.
I'm not saying I wouldn't go the $3,100 centrifigal route, but It's going to take a lot of figures and reassurances that it is the real deal before I jump ship off of Sean's SC
Of course many people know SC better than me, so if anyone has different thoughts, chime in as I am eager to learn more.
the centrifical has more power potential in the end if all other factors such as engine integrety, fuel, etc is taken care of. It is also least parasitic. But power comes on at the upper end of rpm-kind of like when turbos spool up. So it's a little peakier. If you are after pure top end power this is the way to go.
The opcon screw is very linear in that the power increase is much more in line with engine rpm increase. After about 5500 rpm or so I think it may be maxed out. But if you are road racing or street racing where you are often in the 2000 to 4000 rpm it may be a better choice for overall drivability. For my style of driving and intent, Sean's is the way to go for me unless I see claims that the $3,100 centrifigal that make it obvious it's the better choice (besides price)
I know Sean has spent a lot of time working on it to make it right and has posted for quite a while on it. This $3,100 just popped up, so I don't really know much about it. Of course the price seemed awfully good, so I had to at least see what the diference was between the 2 types.
I'm not saying I wouldn't go the $3,100 centrifigal route, but It's going to take a lot of figures and reassurances that it is the real deal before I jump ship off of Sean's SC
Of course many people know SC better than me, so if anyone has different thoughts, chime in as I am eager to learn more.
Hi Guys,
Here's just a little more information for you to ponder.
If, in fact, a centrifugal blower is lower in drag than a twin screw, why do the Viper centrifugals need a keyed crankshaft, 10 rib belt and require more careful belt maintenance at 8 psi boost when the twin screw at 8 psi doesn't slip with a stock tensioner and a 6 rib belt?.....
You also have to think about the bypass valve, which is different that the blow-off valve used on the centrifugal kits. If the blower is in front of the throttle bodies and you're running 4000 engine rpm at 1/2 throttle, the blow-off valve is dumping the excess air charge that is being created, but not used. This draws more power and heats the air charge, since the inlet to the centrifugal blower is open to the filter all the time. So, now you need an intercooler to cool the air charge back down so that you don't get detonation when the throttle is opened and the engine sees that initial high temperature air charge.
With the twin screw system we've been working on, we use a bypass valve. This small valve allows the supercharger to become extremely efficient in terms of economy and parasitic power loss. The bypass is operated by a vacuum actuator control unit that is normally closed. When vacuum is high (idle-cruising) the actuator opens the bypass valve, equalizing the vacuum pressure throughout the system. This recirculates the air from the boost side to the inlet side. When boost is required (accelerating) the vacuum is decreased and the bypass valve instantly closes, which creates instant full boost. This equalized vacuum condition virtually eliminates the normal parasitic power loss of a forced induction system. The air charge is kept cooler and we don't need an intercooler to keep detonation away.
This is not meant to knock the centrifugal systems in any way. They make good power. We just chose to go in a different direction.
Sean
Here's just a little more information for you to ponder.
If, in fact, a centrifugal blower is lower in drag than a twin screw, why do the Viper centrifugals need a keyed crankshaft, 10 rib belt and require more careful belt maintenance at 8 psi boost when the twin screw at 8 psi doesn't slip with a stock tensioner and a 6 rib belt?.....
You also have to think about the bypass valve, which is different that the blow-off valve used on the centrifugal kits. If the blower is in front of the throttle bodies and you're running 4000 engine rpm at 1/2 throttle, the blow-off valve is dumping the excess air charge that is being created, but not used. This draws more power and heats the air charge, since the inlet to the centrifugal blower is open to the filter all the time. So, now you need an intercooler to cool the air charge back down so that you don't get detonation when the throttle is opened and the engine sees that initial high temperature air charge.
With the twin screw system we've been working on, we use a bypass valve. This small valve allows the supercharger to become extremely efficient in terms of economy and parasitic power loss. The bypass is operated by a vacuum actuator control unit that is normally closed. When vacuum is high (idle-cruising) the actuator opens the bypass valve, equalizing the vacuum pressure throughout the system. This recirculates the air from the boost side to the inlet side. When boost is required (accelerating) the vacuum is decreased and the bypass valve instantly closes, which creates instant full boost. This equalized vacuum condition virtually eliminates the normal parasitic power loss of a forced induction system. The air charge is kept cooler and we don't need an intercooler to keep detonation away.
This is not meant to knock the centrifugal systems in any way. They make good power. We just chose to go in a different direction.
Sean
SmokinV10
Enthusiast
Sean,
Ive had older cars (528 Hemi) with older traditional cog drive 871 blowers. These had no bypass valve (that I know of). I understand that the turbo and centrifugal blowers have blow off valves. However would this re-heated air be harmful if it is just vented to the atmosphere (that way only cool outside air is drawn in)? I know you have to have a completely closed system for 50 state emissions certification, but venting a bypass valve could be as simple as disconnecting/plugging a hose. Also if the older blower cars did not require a bypass valve, why do the whipple/autorotors? Is the purpose of this valve for reliability and durability of the compressor? By the way, thanks for that latest post. Helped answer some questions I had about belt strain from the supercharger.
Ive had older cars (528 Hemi) with older traditional cog drive 871 blowers. These had no bypass valve (that I know of). I understand that the turbo and centrifugal blowers have blow off valves. However would this re-heated air be harmful if it is just vented to the atmosphere (that way only cool outside air is drawn in)? I know you have to have a completely closed system for 50 state emissions certification, but venting a bypass valve could be as simple as disconnecting/plugging a hose. Also if the older blower cars did not require a bypass valve, why do the whipple/autorotors? Is the purpose of this valve for reliability and durability of the compressor? By the way, thanks for that latest post. Helped answer some questions I had about belt strain from the supercharger.
David
Viper Owner
Older roots type blowers had efficiencies in the 50% range, which required a lot of drive power and resulted in a lot of heating of the air charge. Progressing cavity screw type blowers have much higher efficiencies -- something like 90% (better than centrifugal compressors). These were too expensive to manufacture until recently. Cheap CNC mills and modern investment casting techniques have reduced the price of these screw type blowers enough to make them competitive. I suspect that, with efficiencies of 90%, the Opcon blower can bypass/recirculate the air charge for lower mechanical drag during cruise without any heating problems.
David's right on target.
Bugeater
Enthusiast
Any new dyno numbers to report?
Also, could you tell us about the intake being used?
Thanks Sean.
Also, could you tell us about the intake being used?
Thanks Sean.
The new intake manifold is a shorter runner design and is manufactured from a solid block of aluminum on a 5 axis CNC mill. The top, where the blower is mounted, bolts on. All dimensions were created in Pro Engineer and we used the same geometric dimensional tolerances as the original factory intake design. 3D modeling was done in step and iges formats.
All components are in production now. The next dyno test will be with the new production parts. We've made several improvements over the prototype system.
Edit - 5 psi on the production kit made 569 RWHP and 594 RWTQ.
The part of the project that's has been taking up the most time is the production side. Defining all lengths, widths, heights, locations, angles, counterbores, finishes, tolerances, etc, of every side of every bracket, flange, plate, rail, hose, etc has been a lot of work. Then you have to have all the parts made...
Having an extrusion die made for the fuel rail, making the rails, then machining them is a 6 to 8 week project alone. To make one single one by hand cutting / welding was easier, but not practical for building more than a few.
We will not have the first kits available in the first week of June as we had hoped and I'm not sure what exact date everything will be ready to ship. But, on a brighter note, the whole kit is starting to look like it was original equipment in regard to fit and finish.
For those on the list that did not get my update e-mail from Sunday with the parts info, let me know and I'll send it to you.
Sean
<FONT COLOR="#ff0000" SIZE="1" FACE="Verdana, Arial">This message has been edited by Sean Roe on 07-17-2002 at 05:08 PM</font>
All components are in production now. The next dyno test will be with the new production parts. We've made several improvements over the prototype system.
Edit - 5 psi on the production kit made 569 RWHP and 594 RWTQ.
The part of the project that's has been taking up the most time is the production side. Defining all lengths, widths, heights, locations, angles, counterbores, finishes, tolerances, etc, of every side of every bracket, flange, plate, rail, hose, etc has been a lot of work. Then you have to have all the parts made...
We will not have the first kits available in the first week of June as we had hoped and I'm not sure what exact date everything will be ready to ship. But, on a brighter note, the whole kit is starting to look like it was original equipment in regard to fit and finish.
For those on the list that did not get my update e-mail from Sunday with the parts info, let me know and I'll send it to you.
Sean
<FONT COLOR="#ff0000" SIZE="1" FACE="Verdana, Arial">This message has been edited by Sean Roe on 07-17-2002 at 05:08 PM</font>
onerareviper
Enthusiast
Sean,
<FONT size="6">YOU ARE THE MAN!!!!</FONT s>
Obviously, this unit is going to be A+++++ quality, and at a price many of us can afford. Thanks for all your hard work!!! Keep it up, as were all waiting patiently....
Later
<FONT size="6">YOU ARE THE MAN!!!!</FONT s>
Obviously, this unit is going to be A+++++ quality, and at a price many of us can afford. Thanks for all your hard work!!! Keep it up, as were all waiting patiently....
Later
99 R/T 10
Enthusiast
Hey Sean, any update on the possibility of your unit being sold for the Gen I cars?
Mike
Mike
Bugeater
Enthusiast
Sean,
Why did you go with shorter runners on a blown application? It would seem to me that you would want to do the opposite! Was it
a matter of package space and/or hood clearance?
Regards,
John
Why did you go with shorter runners on a blown application? It would seem to me that you would want to do the opposite! Was it
a matter of package space and/or hood clearance?
Regards,
John
The prototype had short runners also, we just equalized them on the production manifold. The motor makes a lot more low end torque (because of the blower) and the HP keeps climbing 700 rpm past where the stock manifold takes a nose dive. It works well in our application and we plan to try the same manifold setup on a stock engine without a blower, just to see what it does.
Regarding a Gen 1 ('92 to '96 RT/10) SC setup, our current design does not fit. The stock belt routing and accessory mounting is incompatible. Due to the time and money it would take to redesign those parts, we will "probably not" (but you never know) pursue building a Gen 1 SC kit. Fortunately, there are still the possibilities of a centrifugal kit from Dan, Doug and Jason for interested Gen 1 owners.
<FONT COLOR="#ff0000" SIZE="1" FACE="Verdana, Arial">This message has been edited by Sean Roe on 07-03-2002 at 06:06 PM</font>
Regarding a Gen 1 ('92 to '96 RT/10) SC setup, our current design does not fit. The stock belt routing and accessory mounting is incompatible. Due to the time and money it would take to redesign those parts, we will "probably not" (but you never know) pursue building a Gen 1 SC kit. Fortunately, there are still the possibilities of a centrifugal kit from Dan, Doug and Jason for interested Gen 1 owners.
<FONT COLOR="#ff0000" SIZE="1" FACE="Verdana, Arial">This message has been edited by Sean Roe on 07-03-2002 at 06:06 PM</font>
Tom and Vipers
Enthusiast
To Sean,
Do you have any details about that cast piston failure at 8 psi? Also, I believe the cast pistons are supposed to be hypereutectic and if so, do you know the percentage of silicon?
To Others RE: centrifugal blow-off valve
I really don't understand the use of the blow-off valve. I have used the original Paxton to 9 psi w/o a valve and never saw a need for it. Obviously, a blow-off valve would produce flow in the compressor and require HP to drive it.
Also, turbos don't use blow-offs on the compressor, they use a bypass on the turbine, i.e., waste gate. Very efficient.
General Comment RE: centrifugals
Boost increases at the square of the engine rpm. What is nice about this is that at the torque peak where maximum cylinder pressure and probability of knock occur - there is little boost. At high rpm, when torque is falling, the boost comes to the rescue.
General Comment RE: altitude normalizing
I'm real interested in any method of automatically increasing boost as one goes up in altitude. I spend a lot of time at 6000-9000 ft and I'm not even in the Rockies yet! (HP is 50% at 18,000 ft.)
Do you have any details about that cast piston failure at 8 psi? Also, I believe the cast pistons are supposed to be hypereutectic and if so, do you know the percentage of silicon?
To Others RE: centrifugal blow-off valve
I really don't understand the use of the blow-off valve. I have used the original Paxton to 9 psi w/o a valve and never saw a need for it. Obviously, a blow-off valve would produce flow in the compressor and require HP to drive it.
Also, turbos don't use blow-offs on the compressor, they use a bypass on the turbine, i.e., waste gate. Very efficient.
General Comment RE: centrifugals
Boost increases at the square of the engine rpm. What is nice about this is that at the torque peak where maximum cylinder pressure and probability of knock occur - there is little boost. At high rpm, when torque is falling, the boost comes to the rescue.
General Comment RE: altitude normalizing
I'm real interested in any method of automatically increasing boost as one goes up in altitude. I spend a lot of time at 6000-9000 ft and I'm not even in the Rockies yet! (HP is 50% at 18,000 ft.)
Tom and Vipers
Enthusiast
OMG!
Pro Engineer!
About 5 years ago, myself and 2 partners created a consulting company to outsource for Pratt and Whitney and back then, the PC version of Pro E lease was something like $20-25K per year.
It was OBSCENELY expensive!
I'm assuming some consultant or outsource did the ProE work...
BTW, ProE had simply the best tetrahedra mesher there was back then - even better than ANSYS. I wonder who is best today?
Oh, and ALGOL had this linear tet element that they were promoting. Linear tet! Ha Ha. Get it! Linear! HA HA!
Pro Engineer!
About 5 years ago, myself and 2 partners created a consulting company to outsource for Pratt and Whitney and back then, the PC version of Pro E lease was something like $20-25K per year.
It was OBSCENELY expensive!
I'm assuming some consultant or outsource did the ProE work...
BTW, ProE had simply the best tetrahedra mesher there was back then - even better than ANSYS. I wonder who is best today?
Oh, and ALGOL had this linear tet element that they were promoting. Linear tet! Ha Ha. Get it! Linear! HA HA!
Hi Tom,
The piston failure was on someone elses car with someone elses blower. I don't know much more than what I was told by the installer / tuner, so it's best if I don't say anything that may be incorrect. Suffice it to say, he was giving me some friendly advice about running that much boost on the newer pistons. Between his comments and those from Mahle, I choose not to suggest more than 5-6 psi with the cast pistons. Just not worth the risk (IMO).
Sean
The piston failure was on someone elses car with someone elses blower. I don't know much more than what I was told by the installer / tuner, so it's best if I don't say anything that may be incorrect. Suffice it to say, he was giving me some friendly advice about running that much boost on the newer pistons. Between his comments and those from Mahle, I choose not to suggest more than 5-6 psi with the cast pistons. Just not worth the risk (IMO).
Sean
Tom and Vipers
Enthusiast
Sean,
It looks like pulling the heads/pan is very easy and that upgraded pistons/rods should not be hard to do.
If this is true, such a Stage 2 (or 3) kit would really interest me.
Tom
It looks like pulling the heads/pan is very easy and that upgraded pistons/rods should not be hard to do.
If this is true, such a Stage 2 (or 3) kit would really interest me.
Tom
Tom and Vipers
Enthusiast
...ooops,
I meant ALGOR.
ALGOL is the programming language - I always get the 2 mixed up.
I meant ALGOR.
ALGOL is the programming language - I always get the 2 mixed up.
Viper Fever
Viper Owner
Sean please put me on your list thanks. Im excited
Snake Bitten
Enthusiast
Polished or black anodized? What's up with RED?
