Hellboy dyno update

[Ram From Hell]

Not a bad day, since nothing broke. I'll say that much.

Didn't make nearly as much power as anticipated, but we're looking at either belt slippage or we're running out of supercharger. Boost came up to 6 PSI by 4000 RPM, then gradually sloped off to 3 PSI by 6000 RPM. With no other signs (or sounds) of the belt slipping, plus the boost dropping in nearly perfect proportion to RPM seems to point to the compressor not keeping up with the engine. Still, the tension on the belt isn't particularly good, so I have to consider that slippage may still be at least playing a part.

So, HP peaked around 4000 RPM at around 635.

I'm going to pull the front off of the truck and work out the placement of an additional pulley that I can put additional tension on the belt with, then try it again. If that doesn't do the trick...













...it's going to be turbo time.

 

[RedSrt007]

sounds like the blower might not be giving you enough.

Definitly check slippage (mark the belt / pulleys). Did you datalog it and view boost levels? (notice boost varying up and down /. etc..)?

But with the huge build, Hogan, strykers, etc....the blower probably isnt giving you the CFM.

-Red

 

[JTS VENOM PERFORMANCE]

No worries brohan, it will be a beast when ya get her right:rock: :rock: :rock: :rock:

 

[tinygiants]

Congrats on the dyno success.

This is being controlled with the AEM correct?

When I get my truck back , I will be doing the pulley job as well. One thought, instead of adding a pulley, maybe you can upsize one? On my ROE set up we have a small idler pulley. That pulley gets increased in size when we drop the SC pulley size.

 

[ZCx]

is the belt for the paxton a v-belt, multi groove or gilmer belt drive????
if its not. seems like a gilmer would eliminate the slippage prob:dontknow: :dontknow:
but congrats on getting her to the dyno:rock: :burnout: :rock: :burnout:

 

[SrtBrad]

Eric we all have faith that you will correct the problem.

 

[Big Worm]

Are we going to see some pic's or video?

 

[LitemUp]

What size pulley are you running? stock, 10lbs, or 12lbs. I've seen this blowers produce up to 16 lbs of boost. So don't think its a SC issue. It definetly sounds like belt slippage. Don't give up on the SC. Also are you running an 8 rib belt or a 10 rib belt. That might do the trick since I've seen all of the big boost SC engine using the 10 rib belts.

 

[Ram From Hell]

sounds like the blower might not be giving you enough.

Definitly check slippage (mark the belt / pulleys). Did you datalog it and view boost levels? (notice boost varying up and down /. etc..)?

But with the huge build, Hogan, strykers, etc....the blower probably isnt giving you the CFM.

I looked up the specs on the 2000 head unit, and it's rated for 1400cfm. At what RPM that figure comes from? Doesn't say.

Checking for slippage by marking the belt and pulley isn't terribly helpful, since the belt may have to make lots of passes before coming back to exact alignment with the original mark, and you'd have to know exactly how many that was and know which pass number you were on at all times. Further, this is all assuming that the belt length corresponds in a perfect ratio of length vs. pulley circumference, otherwise it wouldn't work at all. The only way to know for sure would be to track the crank RPM vs. blower pulley RPM.

On the AEM, I can datalog all of the engine parameters. We paid very close attention to MAP vs. RPM. Of particular note is that the boost is always nice and smooth, without sudden changes of any kind that typically indicate slippage. The boost falls off evenly with RPM past 4500 RPM, at almost the same rate as it built up to from 2000rpm.

It is possible that the engine is just outrunning the blower, especially with the ridiculous flow numbers possible with the head/intake combo at higher RPMs. I'm thinking if you can't maintain boost pressure, the volumetric efficiency is going to fall way off. This should be especially true if the compression ratio has been reduced, as it is with this engine. However, I am going to see if I can integrate an adjustable tension pulley before giving up on it.

 

[RedSrt007]

On the AEM, I can datalog all of the engine parameters. We paid very close attention to MAP vs. RPM. Of particular note is that the boost is always nice and smooth, without sudden changes of any kind that typically indicate slippage. The boost falls off evenly with RPM past 4500 RPM, at almost the same rate as it built up to from 2000rpm.

It is possible that the engine is just outrunning the blower, especially with the ridiculous flow numbers possible with the head/intake combo at higher RPMs. I'm thinking if you can't maintain boost pressure, the volumetric efficiency is going to fall way off. This should be especially true if the compression ratio has been reduced, as it is with this engine. However, I am going to see if I can integrate an adjustable tension pulley before giving up on it.

theoretical cfm = rpm x displacement / 3456

Engine Flow= (engine displacement) X (volumetric efficiency) X (engine speed) X (manifold pressure)

That would be my guess is that the engine demand outdoes the blowers capability, especially if your shooting for 1200+rwhp, boost only!

A blower is basically a belt driven turbo, if you were to go with a single turbo (as comparison), with your setup, you would need a tubo at least the size of Dom's. Even a single 76 would be too small..you start to run out of efficiancy, not boost.

Once again, without knowing EXACT details of the motor build, its hard to know exactly what volume of air your truck needs...but just a guess

 

[moparracing]

something seems way wrong here......... shouldn't your truck (with the stryker's, intake & cam) be able to turn close to those numbers without the paxton ??? :dontknow:

 

[Manic]

something seems way wrong here......... shouldn't your truck (with the stryker's, intake & cam) be able to turn close to those numbers without the paxton ??? :dontknow:

I was thinking on the same lines, the paxton seems ineffective at the moment.

Wil

(Keyboard Engineer #310 )

 

[JMB Justin]

There are multiple vipers with Novi 2000's making over 1000WHP, Blake made 1070+ on 15psi with a paxton setup. UR has made over 1000WHP on 93 octane in a gen 2. If it belt slipped you should have dust everywhere from it. IMO a 1400CFM blower is awfully small for these motors (when modded), but it seems to have worked for others. A big procharger (or TURBO )would make a huge difference, but you have to start from scratch almost at that point as the brackets, air intake, intercooler piping, etc. all would be different.
Justin

 

[FSTJACK]

What camshaft are you using and how much overlap at .050" does it have ?

What intake lobe center is it installed on ?

 

[pokeytemplar]

Ram of Hell,

I have to agree that you're supercharger is not keeping up. Those that are hitting the 1000HP mark have to over-spin the Paxton supercharger. I called Procharger earlier this week discussing their D1 and F1 units. They stated the D1 would only work satisfactorily on stock engines (1400CFM) and recommended the F1-R for modified engines (2000CFM). Hopefully this information helped.

 

[Ram From Hell]

something seems way wrong here......... shouldn't your truck (with the stryker's, intake & cam) be able to turn close to those numbers without the paxton ??? :dontknow:

As a matter of fact when Arrow engine-dyno'd it, it produced 617 peak horsepower through a stock intake, injectors, ECU, and no Paxton (all at 9:1 compression)!

I went for a nice long drive today, and came back with half a serp belt. I'll be tearing into it tomorrow and seeing if I can devise an adjustable means of putting more tension on the belt, while I'm checking for the source of the alignment issue. I'm also wondering about that overdrive crankshaft pulley I installed. The belt doesn't wrap half way around the stock one. The bigger pulley may well be prone to serious slippage, and the dust from it would be tough to see. Ideally, I'd figure out a way to get more wrap and tension on that pulley.

Even if I solve this problem, I have a feeling that this compressor may not get me where I want to be power-wise. However, I do have that "little" 300 shot nitrous kit waiting to be installed...

 

[pokeytemplar]

How many HP are you shooting for on just boost? By your numbers @ 4000RPM your are producing around 833ft/lbs of TQ. What sucks the most is that Paxton doesn't make a larger unit. Procharger will send you a mock-up unit for you to fabricate your own brackets. You could probably still use the Air/Water intercooler. Refundable $700.00 for the F1 mock-up kits.

By my calculation you should be getting around 8psi boost @ 6000rpm once you get rid of the belt slip and if the Paxton is a peak flow at that RPM.

 

[JTS VENOM PERFORMANCE]

any updates bro?

 

[Big Worm]

hope you get it fixed brother.

 

[Ram From Hell]

Just finished tearing down and cleaning everything up this weekend. It was a genuinely catastrophic mess. I also stripped all of the lines and fittings off of everything. All the shiny stuff's getting coated. I'm done with polishing, and I want a daily driver that I don't have to sweat the cleanup.

I have a plan for fabricating an assembly that will attach to the belt tensioner that will allow for an adjustable amount of increased tension. We'll see how that pans out.

The parts will be back from coating in a couple weeks. Should be back up and running Oct 1 (about the three year anniversary of breaking the first engine).