Get more boost from your Roe Blower!

[Schulmann]

I have been using a 6 rib belt for a while without trouble with the 6.5lb pulley. I have an ACR and no AC, the 7 rib belt is not available for my viper.

 

[Simms]

Thanks, keep us posted.

 

[Shelby3]

Just got off the phone with Sean who recently did a car with the Weaver crank pulley. The car made about 11.5lbs of boost with the Weaver crank pulley, an 8lb blower pulley and the small idler pulley that you use with the 10lb system. Sean has custom 2500 seven rib belts made to work with this configuration. A big advantage in addition to the boost increase with the smaller blower pulley but larger crank pulley is the significant reduction in any belt slip. I ordered the 8lb pulley and the 2500 seven rib belt and will install them tomorrow when they arrive.

 

[Shelby3]

Received 7 ribbed belt from Sean but no 8lb pulleys in stock at this point. Ran some street pulls with the 2.5" blower pulley and saw 14lbs on the boost gauge. AFR looked good, ambient air temp was 56 degrees. Power under the curve seemed stronger. Will get on the dyno when the weather warms up a bit today or tomorrow.

 

[Earl_H]

How much extra power are you guys seeing from the extra boost? At what point will the twin screw max out its airflow capacity. What do your IAT's look like?

 

[ViperRichRT10]

Well, I just got my car back on the road and David's new pulley seems great! I am running the 8lb. pulley with David's crank pulley and am seeing 12.5-13lb. of boost on my guage and on the dyno! The torque at low rpm and responsiveness is awesome. I also have Greg Good mack daddy heads. Actually more boost than I expected.

Thanks,

Rich

 

[N2 Vipers]

And the dyno said?????

 

[Joseph Dell]

Dyno said "your stock fuel pump is running out of fuel past 5000rpm". But it also said 650rwhp and 710rwtq on a heat-soaked motor. The HP was headed in the UP direction until the fuel starts to disappear. this was on 93 octane.

We knew the stock fuel pump wasn't going to be enough, but we ran a 50/50 Water/**** mix to get some more octane out of the setup. And it sounds soooooooo nice.

Next step - install the boost-a-pump and put in some 104 UNL. Should be fun!

JD

 

[N2 Vipers]

Awesome! Keep us posted.

 

[ViperRichRT10]

And I might add.....THANKS JOESEPH DELL!!!! Awesome job tuning and helping me put this whole thing together!

 

[BlueGTS]

Spill some of the dyno numbers!

 

[RedEnuf93]

I'm installing the Roe Blower soon, any more info???

 

[vegasviper]

So if the max rpm of the blower is 21000, what would be the size of blower pulley to use with the Weaver Crank Pulley to be at 21000RPM

 

[FE 065]

I posted a link to THIS ARTICLE once before that talks about overspinning roots type blowers.

The article is partially titled "Hey, let's boost a 7 psi kit to 12 pounds and see what happens..." and talks about what heat does to blower bits inside the case.

How much of it, if any is applicable to Roe blowers, those-that-know will have to decide. I'm re-posting it in case there's some of it that applies.

Besides there's some other good articles at this website

 

[1TONY1]

So if the max rpm of the blower is 21000, what would be the size of blower pulley to use with the Weaver Crank Pulley to be at 21000RPM

That is a darn good question. And what rpm does the 10lb and 12lb pulley take the blower to (at 6000 rpm)
The Weaver pulley is a very nice piece and I will be trying it with a 10lb upper one day when my fuel system gets better.

As far as the heat damage from the link....I think the heat issue is not a problem with the water/methonal.

 

[99 R/T 10]

Bump, hoping for an answer on this issue.

 

[David Weaver]

So if the max rpm of the blower is 21000, what would be the size of blower pulley to use with the Weaver Crank Pulley to be at 21000RPM

You would want to use the Roe 2.3 inch pulley (12 lb pulley) to get the maximum of 21,000 blower rpms at 6000 engine rpms. This pulley has also been great for helping eliminate belt slip. You can run my pulley with a 10 lb pulley and still make 12 lbs with less belt slip (more pulley surface area for better belt adhesion on the blower pulley).

DW

 

[Nadine UK GTS]

Hi David, any update on making a larger power steering pulley please?

 

[ViperRichRT10]

bump

 

[SUN RA KAT]

I have the David Weaver pulley and also Jeff Morys Striker street version heads and a custom Larry Macedo cam.

I'm having a lot of street driveability problems and have been told the VEC2 can't handle what I have and will have to go with the AEM system to safely drive it on the street.

Below my signature is what kind of power my setup made in Florida.

 

[JohnnyBravo]

I have the David Weaver pulley and also Jeff Morys Striker street version heads and a custom Larry Macedo cam.

I'm having a lot of street driveability problems and have been told the VEC2 can't handle what I have and will have to go with the AEM system to safely drive it on the street.

Below my signature is what kind of power my setup made in Florida.

Kenny,

What kind of street drivability problems are you having?

High end miss?
Partial throttle stumble?
Poor transition from vaccuum to positive manifold pressure?

With all the time and money you have invested with your tuner, I would have hoped for 100% flawless performance out of that beast.

 

[SUN RA KAT]

I have the David Weaver pulley and also Jeff Morys Striker street version heads and a custom Larry Macedo cam.

I'm having a lot of street driveability problems and have been told the VEC2 can't handle what I have and will have to go with the AEM system to safely drive it on the street.

Below my signature is what kind of power my setup made in Florida.

Kenny,

What kind of street drivability problems are you having?

High end miss?
Partial throttle stumble?
Poor transition from vaccuum to positive manifold pressure?

With all the time and money you have invested with your tuner, I would have hoped for 100% flawless performance out of that beast.

I drove the Viper yesterday and it started and ran for 15 seconds and died. Restarted it and warmed it up, then shut it off so it wouldn't be stuck in a cold start loop. Restarted it again and ran some errands. Low RPM surging made it very unsafe to drive in traffic.

Blew the fuse to the PCM twice on Sturday while on the dragstrip. The fuse problem only happened twice at full throttle in 4th gear and it may be fixed, but it's only made one run in 4th gear at full throttle since and it was OK, so I'm not 100% sure. It runs great at high RPM, but the normal street RPM is where most of the problems are.

My Viper was supposed to be daily driver reliable with more power. It came back to me much more like a race car with very little daily driver reliability.

Looks like it will take quite a bit more money to get an AEM and install it and tune it to fix the hard starting and surging problems and high idle hang up. I was told the VEC2 is great up to a certain level, but the Jeff Morys Striker heads have crossed that level and can't be tuned properly with the VEC2. I had talked with Jeff Morys at length about his heads and street driveability before I got them and was promised there would be no problems with the Roe Supercharger and his Striker heads. They flow so much that the Roe Supercharger can't keep up with them, even with the David Weaver Pulley.

I am totally surprised that my tuner went ahead and got the Striker heads since he is an expert with the capabilities of the Roe Supercharger and the Striker heads are not very compatible with the Roe. The car was also delivered to me in an absolute undriveable state in hot weather - the low RPM surging made it too dangerous to drive in traffic and too unsafe to drive at all if the temperature got above 85 degrees. My Viper Tech grounded the TPS & the PCM and 90-95% of the surging was gone, but the remaining surging is still too dangerous to drive in traffic. My tuner has retuned the VEC2 cards for the difference in altitude from Florida to Ohio and opened up the Water/methanol to come on much sooner, both of which has really made my Viper much more driveable. But now it is very hard to start when cold, it still usually gets stuck in a loop and has to be shut off and restarted before driving on the street, it still has high idle hang up for 30-45 seconds with clutch pressed in and will hold the high idle almost indefinately in gear, and the surging is still present at a dangerous level, and it still throws Code P0171 randomly.

Also it will have to go back down to Florida soon for retuning after the AEM is installed.

I've been extremely depressed about all of this. I was promised daily driver reliability with no codes and more power (at least the high 700's) for a certain price and very few of the promises have been met to date. And it looks like it will take quite a bit more money to hopefully have the promises be kept. My tuner has been really trying to get my Viper right, but the new costs to make it streetable after I already paid for a streetable car just don't seem right. I feel like I am being held hostage by my Viper.

 

[JohnnyBravo]

I have the David Weaver pulley and also Jeff Morys Striker street version heads and a custom Larry Macedo cam.

I'm having a lot of street driveability problems and have been told the VEC2 can't handle what I have and will have to go with the AEM system to safely drive it on the street.

Below my signature is what kind of power my setup made in Florida.

Kenny,

What kind of street drivability problems are you having?

High end miss?
Partial throttle stumble?
Poor transition from vaccuum to positive manifold pressure?

With all the time and money you have invested with your tuner, I would have hoped for 100% flawless performance out of that beast.

I drove the Viper yesterday and it started and ran for 15 seconds and died. Restarted it and warmed it up, then shut it off so it wouldn't be stuck in a cold start loop. Restarted it again and ran some errands. Low RPM surging made it very unsafe to drive in traffic.

Blew the fuse to the PCM twice on Sturday while on the dragstrip. The fuse problem only happened twice at full throttle in 4th gear and it may be fixed, but it's only made one run in 4th gear at full throttle since and it was OK, so I'm not 100% sure. It runs great at high RPM, but the normal street RPM is where most of the problems are.

My Viper was supposed to be daily driver reliable with more power. It came back to me much more like a race car with very little daily driver reliability.

Looks like it will take quite a bit more money to get an AEM and install it and tune it to fix the hard starting and surging problems and high idle hang up. I was told the VEC2 is great up to a certain level, but the Jeff Morys Striker heads have crossed that level and can't be tuned properly with the VEC2. I had talked with Jeff Morys at length about his heads and street driveability before I got them and was promised there would be no problems with the Roe Supercharger and his Striker heads. They flow so much that the Roe Supercharger can't keep up with them, even with the David Weaver Pulley.

I am totally surprised that my tuner went ahead and got the Striker heads since he is an expert with the capabilities of the Roe Supercharger and the Striker heads are not very compatible with the Roe. The car was also delivered to me in an absolute undriveable state in hot weather - the low RPM surging made it too dangerous to drive in traffic and too unsafe to drive at all if the temperature got above 85 degrees. My Viper Tech grounded the TPS & the PCM and 90-95% of the surging was gone, but the remaining surging is still too dangerous to drive in traffic. My tuner has retuned the VEC2 cards for the difference in altitude from Florida to Ohio and opened up the Water/methanol to come on much sooner, both of which has really made my Viper much more driveable. But now it is very hard to start when cold, it still usually gets stuck in a loop and has to be shut off and restarted before driving on the street, it still has high idle hang up for 30-45 seconds with clutch pressed in and will hold the high idle almost indefinately in gear, and the surging is still present at a dangerous level, and it still throws Code P0171 randomly.

Also it will have to go back down to Florida soon for retuning after the AEM is installed.

I've been extremely depressed about all of this. I was promised daily driver reliability with no codes and more power (at least the high 700's) for a certain price and very few of the promises have been met to date. And it looks like it will take quite a bit more money to hopefully have the promises be kept. My tuner has been really trying to get my Viper right, but the new costs to make it streetable after I already paid for a streetable car just don't seem right. I feel like I am being held hostage by my Viper.

Oh man, Kenny. That really stinks. I feel terrible for you. I know how excited you were about the project and I almost felt like a part of it by the way you kept everyone posted on the new goodies and the status of the build.

Because I am also a Roe supercharged Viper owner, I was very excited to see what could be done with your car by adding heads/cam. I thought the Stryker heads were probably a little overboard, but I'm not a tuner so I just figured I'd wait and see what happened with your car.

Before you pull the VEC2 and throw more money at the car, you might want to talk to Joe Donovan in St.Louis. I know he's personally tuned several blower/head/cam cars INCLUDING one with the new Stryker heads using the VEC2. It may be something as simple as rewiring something or just a simple adjustment to the water/**** or fuel delivery charts. I swear that guy can do more with a VEC2 than just about anyone other than maybe Sean Roe. That's not a slam on any of the nationally recognized tuners, it's just my own personal observation from the work he's done on my car and dozens and dozens of other satisfied Viper owners.

I'd hate to think that someone in the Viper community spend nearly $30,000 on their car only to be "depressed" and "disappointed" by what they got in return.

Before you dump a ton of additional money in the car, call Joe.

I hope you get everything worked out. There's nothing worse than having something take all the joy out of your favorite toy.

 

[SUN RA KAT]

I just had a long talk with Joe and he's pretty sure he can fix all the problems using the VEC2 - thanks, JohnnyBravo!

This is the second or third time Joe's name has come up since Saturday.

 

[JohnnyBravo]

I just had a long talk with Joe and he's pretty sure he can fix all the problems using the VEC2 - thanks, JohnnyBravo!

This is the second or third time Joe's name has come up since Saturday.

Not a problem at all, Kenny. I'm telling you....that guy might as well have a big "S" on his chest when it comes to Viper tuning.

I just want to see you get that beast all ironed out (without spending a ton more money). It's obvious your car has a lot of potential. If there is any more HP or drivability to be gained, Joe will find it.

I'm looking forward to having Joe (and Greg Good) do my new head/cam/overdrive pulley setup in the fall. We're waiting until after VOI and until the weather cools down just a tad.

Keep us posted on the EEKMOBILE.

 

[Schulmann]

SUN RA KAT,

Sorry for your troubles.

There are a couple of "heavy" racers on this forum using VEC2 with a lot of succes. We don't have any major problems that the VEC2 can not solve. Others can confirm this. It is a very good tool. AEM is also a great computer doing more staff but requires a lot of time to tune.

Regarding your troubles:

In your case, VEC2 should only work from 10mhg vacuum.
Everything else should be handle by the PCM.
Viper engin idles around 12mhg a too early dial-in might cause this issue.

Instable idle is also caused by a poorly adjusted Throttle Body Sensor and throttle bodies. In fact a lot of idle issue comes from this TPS sensor. It must absolutely provide 0.70-0.80 volt at idleing. Anything else will cause sever swing in the idle speed. It is caused by the fact that the PCM advances the ignition 15 degres right away when it receives 0.81V and when engin is hot.


The P0171 code indicates another poor adjustment in your fuel trims.
The P0171 code is only thrown in closed loop operation.
Missing fuel can also cause poor idling issues.


Really your case sounds like a poorly tuned Viper. The guy you paid for tuning didn't do his job. The basic parameters could easily be fixed by a professional tuner within an hour. Then you could spend time to pull more HP from your Viper.


It is said that this type of tuner still exists to-day

 

[martyb]

Hey Johnnybravo,

My car will also be at Joe's this fall for a heads/cam package to add to my exising Roe supercharger. Anyone that has worked with Joe knows he is THE man in the midwest. I see his name all over the LS1, SVT boards all of the time, he is making quite a name for himself. If he lived in the Chicago area, I would go work for him for free just to gain some of his expertise. The man knows his stuff!!

martyb

 

[JohnnyBravo]

Hey Johnnybravo,

My car will also be at Joe's this fall for a heads/cam package to add to my exising Roe supercharger. Anyone that has worked with Joe knows he is THE man in the midwest. I see his name all over the LS1, SVT boards all of the time, he is making quite a name for himself. If he lived in the Chicago area, I would go work for him for free just to gain some of his expertise. The man knows his stuff!!

martyb

Marty,

You are absolutely right. His knowledge of building/tuning fast cars has spilled over into several different markets now (Mustang, Camaro, Viper, Supra, etc). On top of his knowledge of cars, he is just a SUPER cool guy to be around.

Unfortunately, his sterling reputation has also resulted in increased turn around time on some projects. Because he is sooooo incredibly good at what he does, and so busy, and so protective of his excellent reputation, he doesn't really let anyone else touch his customers' cars. He is pretty much a one man show over there. The upside is that you know the only hands that have been on your car are Joe's and that the project will be perfect. The downside is that you have to wait your turn. That's still a VERY fair trade-off in my opinion. I'm willing to wait a little longer for a perfect product.

 

[martyb]

Well said Johnnybravo. I think Joe mentioned that your car is right after mine!!!!!

I went out for a night on the town with Joe a few weeks ago, had a blast. We will have to meet up at his shop one of these days.

martyb

 

[Joseph Dell]

Joe is the man. And he can fix your problems.

Without making you feel worse than you already do...

Your combo is a new combo that had never been tested... you even said in a previous post that you were taking off the stryker heads! What inspired you to keep them (BTW- if you want to sell them, i'm probably buying a set this week so pipe up soon)...

But the truth is that the tuninng w/ an AEM is just as easy as w/ a VEC2 IF (and i scream IF !!! ) if you know what you are doing. And to all those who say that the VEC2 can't handle it... well, the VEC2 has some limitations but MOST can be worked around. Sure, 2500 for the AEM + accessories is a BETTER way to go, but there is no reason (unless you are running really big injectors) that the VEC2 can't handle it.

I don't personally trust the VEC2, but that is b/c I've done a boat load of data logging and the V-notch problem is quite real... and the "fix" for it (mod the IAT sensor) just tells the computer that the car is always taking in air under 95 degrees. Not a very good hack...

What size injector are you using?

Idle problem / surge probably = vacuume leak.

But that is my limited knowledge of the problem.

If you wanted a high-HP daily driver, there are pleanty of "established" combos that work. But you wanted [you really really really] wanted to do this w/ a ROE. And that is like going out and buying a picture tube TV today to watch sports: it has its limits. And you are seeing those.

I feel for you. I really do. I've spent my share of $$$ being the 'first' to do things. And I've made my mistakes. But you want the truth? sell the ROE for 4k, but a new paxton for 7k, don't buy the AEM, get it installed in a weekend, tune it, and be happy. you'll be MORE streetable than you were before and you'll have something that you can grow with.

But I'm just an engineer and it's your money. for _whatever_ reason you wanted ROE. If you _still_ want ROE, then accept the fact that you'll never have the power of the other guys. If you keep the ROE, then either let Larry, your original tuner, make it right... or give it to Joe. Both are stellar guys. Both will make it right. But now that you've opened this can of worms RE: Larry, you really ought to give him the chance to fix it.

But it's your money. Do your research, make your decision, then go out and drive.

And it is never to late to change your mind. besides... you paid by CC, right? Go dispute it... If you did a cash / wire payment, shame on you!!!

Just my .02...

And worth taking a break from working in order to respond.

Good luck!

JD