Before and after HP / Torque graph with 8 PSI bolt on blower ...

[Sean Roe]

Hi Everyone,

We don't do many installs of our blower kits (maybe 9 or 10 of 155 kits built so far, since most are out of the state or country), but Monday afternoon a local owner dropped off his red '97 GTS with smooth tubes, filters and cat-back exhaust (all else stock). We dyno tested it and let it cool off overnight. Tuesday we installed the blower with a 2.65" (8 psi) pulley, 50 lb/hr injectors, 180 thermostat, flushed / filled the cooling system and test drove it. This morning we dyno tested the car before he came to pick it up and I present the graphs below.

The first is SAE corrected numbers, the second is actual recorded numbers (it was much cooler this morning than it was Monday afternoon). The car had 93 octane gasoline and the standard 9D program card.

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Obviously, this is not as powerful as MBN's car that we did, which produced 903 actual rear wheel HP, but I am proud of it too. Dave in our shop did the install. He does the pre-assembly of all the Supercharger kits before they ship out and this was his first actual install. Just thought you guys would like to see the results of and ordinary day at the shop installing an ordinary, off the shelf, Supercharger

Regards,
Sean

 

[1TONY1]

Re: Before and after HP, Torque and Air /fuel graph on 8 PSI bolt on blower..

Nice. The deal in my sig is still good. FREE INSTALL !!!

 

[Sean Roe]

Re: Before and after HP, Torque and Air /fuel graph on 8 PSI bolt on blower..

Nice. The deal in my sig is still good. FREE INSTALL !!!

Thanks Tony. It wasn't always this easy, was it? Hard work pays off.
Free installation? We charged $550 for the install with the thermostat labor.

 

[RedGTS]

Re: Before and after HP, Torque and Air /fuel graph on 8 PSI bolt on blower..

Hi Sean. Anything new on the intercooler? Thanks!

 

[Sean Roe]

Re: Before and after HP, Torque and Air /fuel graph on 8 PSI bolt on blower..

Hi Ronnie,
Yes actually. Now that we've got some big projects done and out of the new shop, we're back to working on it and testing. Additionally, we've hired a former engineer from Autorotor in Sweden to come over and work with us a while on it, the G1 and G3 kits.
Regards,
Sean

 

[Cudaman]

Re: Before and after HP, Torque and Air /fuel graph on 8 PSI bolt on blower..

Congrats on dyno numbers and with the impressive "stock" 8 PSI install.

Equally impressive to hear that you have hired a former engineer from Autorotor in Sweden to come over and work with you on the G1 and G3 kits.

But I know everyone is VERY excited to hear about the intercooler work! Also it is back on the your busy work schedule, can't wait to hear the results.....I wonder if the the Autorotor engineer has any ideas on the intercooler.

I am also glad to hear the creator of the Roe Supercharger will be attending the Florida V-10 Nationals Saturday Feb 7 and/or Sunday Feb 8 in Bradenton.

Also Larry Macedo will also be there. The creator and the tunner the fastest Roe Supercharged Vipers in the world, will be there both watching their creations SCREAM(or sound like a Jet engine) down the track. Maybe they will BREAK WORLD records or possibly set new ones.

Cudaman

 

[ROCKET62]

Re: Before and after HP, Torque and Air /fuel graph on 8 PSI bolt on blower..

Sean,

How do you decide on 5, 7, or 8 lb psi pulley?

PS - been saving my pennies for that Gen 1 configuration!

 

[ViperBing]

Re: Before and after HP, Torque and Air /fuel graph on 8 PSI bolt on blower..

Very impressive! Any idea what it might run at the track?

Is that with stock cats?

 

[Larry Macedo]

Re: Before and after HP, Torque and Air /fuel graph on 8 PSI bolt on blower..

Very nice numbers, Sean! Bring the car with you next weekend for the V10 Nats.

 

[Sean Roe]

Re: Before and after HP, Torque and Air /fuel graph on 8 PSI bolt on blower..

Sean,

How do you decide on 5, 7, or 8 lb psi pulley?

....

First, we consider the year of the car and whether or not it has forged pistons (forged pistons were OE through 1999). If the pistons are forged, we can consider boost higher than 5 psi. If they're cast, we recommend the lower 5 psi pulley.

Next, we consider the fuel octane available. Let's say you have forged piston car, but are only able to run 91 octane. Well, you can go up to about 7 psi, but may need to run a little extra timing retard on the VEC2 program card. If you have 93 octane or higher, you can consider 8 psi. Of course, there are other factors that come into play other than what I described here, and that's what we look into when helping someone determine the right boost level and injector size for their application.

"Is that with stock cats?" On this particular car, no. Always keep in mind that the stock cats were designed for the stock engine and street driving with a typical air /fuel ratio of 14.7:1. Wide open throttle stock A/F ratio gets down to about 12.0:1 and with a Supercharger we run the at about the same or down to 11.5:1 (depending on conditions). Lower A/F ratios lead to hotter cats. Since the cats are in the side sills and surrounded so they don't get air flow, they can get too hot. If a Viper does not already have high flow cats (or no cats for off road use) before the SC install, we recommend them at the time of the SC install.
I inadvertently left high flow cats off the mod list, saying the car was stock before the Supercharger install, except tubes / filters and fabricated cat-back. That was my mistake. We had no knowledge or previous history with this car (apparently used to run in Viper Days). However, the gain shown on the dyno graph is still valid as a before and after comparison of the gains produced by the blower alone.

Larry,
I don't think the owner of this particular '97 will be attending the drag races. I told him about them, but I think he did the blower just for the fun factor of having the additional power. He was pretty stunned after getting on it outside the shop.

Regards,
Sean

 

[RedGTS]

Re: Before and after HP, Torque and Air /fuel graph on 8 PSI bolt on blower..

He was pretty stunned after getting on it outside the shop.

I bet not half as stunned as whoever is driving that dyno-******* Mbn car at about 3300 rpm. Will that car hook up at all below 80-100 mph?