Great dyno day: Roe Supercharger

[Schulmann]

Unfortunately when I bought my supercharger it was not at all indicated in the user manual that when tuning too much we might develop a sever HP addition. As many of you I also suffer from this HP addiction. I started with a small 5lb pulley and now I am running on a 8lb pulley.
To-day we did a couple of great runs on the 8lb pulley. The dyno guy was new and he didn’t know how to operate properly the dyno and the computer. We had to call Sean to ask him some advice. Sean was great to help us out very quickly.


I wanted to share with you some interesting dyno data. It might help other people in their tuning work.

5lb pulley:
Everything was stock on the Viper.
Runs great on 91 oct fuel and is very powerfull on 94oct fuel.
Very easy to tune and doesn’t require much retard.
Not hard at all on the engin. A lot of fun while driving.

6.5lb pulley:
Mods: 3’’ headers and exhaust, 1.7 rocker, W/M, Allum fly wheel, Roe air duct
The 6.5lb pulley is the most streetable option.
It runs great on 94 oct fuel.
Requires 10deg retard on 91 oct fuel.


8lb pulley:
Same mods as on 6.5lb pulley.
Requires very sever retard on 91 oct fuel.
Runs great on 94 oct fuel.
A lot of tire speen in lower rpms.
I will likely upgrade my wheels and tires ...

<font class="small">Code:</font><hr /><pre>
Leakdown test at 10k miles and at 30k miles


#1 8%/10% #2 7%/15%
#3 9%/10% #4 16%/18%
#5 11%/10% #6 9%/10%
#7 10%/10% #8 8%/12%
#9 11%/15% #10 10%/15%
</pre><hr />

<font class="small">Code:</font><hr /><pre>
RPM 5lb 6.5lb 8lb
hp/tq hp/tq hp/tq
============================================================
2500 181/478 261/548 286/600
3000 294/514 335/587 367/643
3500 356/529 404/606 438/657
4000 407/535 461/605 506/665
4500 432/504 510/596 562/656
5000 481/505 559/587 601/632
5500 504/481 591/565 630/601
6000 496/434 600/525 621/544
</pre><hr />


I would like to post pictures but I can't log into my VCA picture gallery ...

 

[SYNFULL]

That's great info. Is the w/m required or needed with the 6.5 pulley?
Thanks
Gary

 

[Mccarlin]

That's great info. Is the w/m required or needed with the 6.5 pulley?
Thanks
Gary

It is required on the creampuffs

 

[KenH]

Hey Andras,
Your numbers look pretty good. You mention that you ran 10 degrees retard on our 6.5lb setup on 91 octane. Are you saying you ******** this much just in the low RPMs or across the entire RPM range? Seems like pretty good HP with that much retard dialed in. I still get occasional detonation on 92 octane, but I haven't tried dialing in near that much retard from stock.

 

[Schulmann]

Above 5psi the ignition base is 6 degree

 

[BlueGTS]

First off, great numbers!

I do have 2 questions from looking at the pictures. The first is your TQ seams to drop off very quickly after 4200. Did the 5psi graph look the same but with lower peak numbers? Second, your AF on the dynojet was absolutely perfect and you can see that in your passenger O2 as well. However, your driver's O2 looks to be set up wrong or needs to be calibrated.

My O2's never give as consistant, none spiking, reading as you got out of your passenger O2. Great work.

 

[Mr Hemi Head]

Nice numbers Andres

Refering to the graph, why are the A/F values for the left and right bank so far appart? Why the spikes in A/F curve? There is major boost creep, did you see that much with the 5 and 6.5 lb pulley?

 

[Schulmann]

You guys really go into the details.

On the passanger side I have a LD-1 from innovate. It runs great.

On the driver side I have a Dynojet WBO. When I bought this device the LD-1 was not available. Dynojet's WBO runs poor, likely misses some sort of calibration. Unfortunately it can't be done. So stay away from this product !

Likely I could improve something around 4000rpm and 5500rpm. But the gain would be no more than +10/20 hp. To gain it I would have to torture my engin. For a racer the AFR could be leaned out to 12 that would yield also a couple of HP.

I have a very reliable setup. My engin runs great and I want to keep it so.
As you can see my engin is still very healthy.

 

[Shelby3]

I've never seen torque drop off that fast on a ROE blower.

 

[BlueGTS]

I think your AF is dead on, I try to get mine at 11.5 as well to be on the safe side. I am surprised that with RR and headers you are getting as much boost creap as you are. With my 10psi pulley I only get to ~ 10.8psi and it looks like you get to 10.0 on the 8psi pulley.

 

[Shelby3]

I think your AF is dead on, I try to get mine at 11.5 as well to be on the safe side. I am surprised that with RR and headers you are getting as much boost creap as you are. With my 10psi pulley I only get to ~ 10.8psi and it looks like you get to 10.0 on the 8psi pulley.

With stock heads you will get boost creep.

 

[Mccarlin]

I've never seen torque drop off that fast on a ROE blower.

same here. on my dyno the torque stays above 600ft/lbs from 2krpm till redline when we let off. no drop like that in torque at all.

 

[KenH]

I think your AF is dead on, I try to get mine at 11.5 as well to be on the safe side. I am surprised that with RR and headers you are getting as much boost creap as you are. With my 10psi pulley I only get to ~ 10.8psi and it looks like you get to 10.0 on the 8psi pulley.

With stock heads you will get boost creep.

I see 8-10 with my 6.5lb setup and stock heads, but it seems very inconsistent.