NEW VR-4 KITS FOUND!!!!

[Michael]

What's the purpose of modeling this supercharger?

Just for fun.

[Duke]

I spoke with Craig at paridise wheels this evening and he definately going to make another run of the vr 4 kits this fall as soon as he moves to his new place im on the list now too. im sick of only 7#s of boost now i can really have some fun!

[silverhawk]

What are the chances you could post up an .sat or .stp or para solid file of the assembly? I'm looking to model one in to come up with a bracket on my motor. I really only need the housings to figure out clearances and alignment. Thanks for any help.

[Michael]

What are the chances you could post up an .sat or .stp or para solid file of the assembly? I'm looking to model one in to come up with a bracket on my motor. I really only need the housings to figure out clearances and alignment. Thanks for any help.

Sorry, but there's little chance of posting any CAD file. I don't share/sell any of my CAD work.

However, if you need help coming up with a bracket for your application, I'm more than happy to try and help out. Send me a PM or an email and we can talk about you're application.

[silverhawk]

No problem, just didn't want to re-invent the wheel if at all possible. I just need the outside dimensions really for the bracketry so I'll draw it up as a single part which should be less complicated and faster all though not near as cool as what you have put together. I have a sn93 to pull all the measurements from. I'm working on twin supercharging a Studebaker. I have the OEM bracket for the passenger side drawn up already (from factory blue prints) but I have to come up with something for the other side and wanted to through it all together in CAD.

Good luck on the VR-4 project.

[Makahveli]

I talked to Craig earlier this year and he told meyou can't use the VR4 on any engine, must be an 8 rib belt with v8 kinda power. I wanted it for my 4.0 explorer with the snow methanol kit but that detered me so I just went with a SN2000 model.

[Michael]

I talked to Craig earlier this year and he told meyou can't use the VR4 on any engine, must be an 8 rib belt with v8 kinda power. I wanted it for my 4.0 explorer with the snow methanol kit but that detered me so I just went with a SN2000 model.

I've heard Craig deter a lot of people from using the VR-4 in favor of SN units. His belief is that it's a true "race blower" and should only be used as such - in high-strung, competitive applications were the blower won't see continuous, long-term use. His reasoning behind this is because the VR-4 required much higher ball-drive pressure than a standard SN unit so it tends to wear the drive balls, races, and impeller shaft much quicker than the standard SN.

However, there are a number of people on here that have been running VR-4s in street applications for years without issue. The argument for going with a 6-rib vs. 8-rib when running a VR-4 will largely have to do with whether or not belt slip is experienced with a 6-rib setup first.

But as far as I'm concerned - and I'll be the first to say I have no experience running a VR-4, either on the street or in competition - as long as the blower has been assembled in the proper fashion (without too high a ball pressure), the correct pulley sizes are used, and you change the fluid regularly, a VR-4 should last as long as (if not longer than) any well-maintained SN.

[Michael]

After a very long delay over the last while, due in large part to me starting a new job (which has required a move to the United States), the SN-4 impeller is now done! Well... the CAD model is now done.

Below are some renderings of the CAD model itself:





As you can see, the SN-4 impeller is the same swept-vane design as the VR-4, except the vane profile is such that it will fit within the smaller volute size/diameter of the SN rear scroll cover.

Here's an image showing a comparison between the SN-4 (on the left) and the VR-4 (on the right). The diameter of the VR-4 impeller is slightly larger than the SN-4, but the volute diameter is considerably larger! It's no surprise the VR-4 flows as much as it does.



The next step is to attempt to conduct some CFD analysis on this new SN-4 impeller design. This will serve two functions. 1. it'll help validate the impeller's design, and 2. it'll help to tweak the design in order to optimize the potential airflow/boost gains. Ultimately, the last thing anybody wants is to discover there isn't any gain from going with a swept-vane design on an SN supercharger.

I'll keep everyone posted with respect to the CFD analysis results. With luck, if the data comes back favorable, machining the real thing will be next on the list!

[whodwho]

Looks great!

I wonder if they ever tested different designs 'back in the day' or just stayed with the original(and the slightly modified). Maybe at the time without good management options they felt that it was the max for the average car these were to go on could handle.

Welcome to the States, what part?

[Buck-Strickland]

Looks great Michael! Very interested to hear back on the flow information.

[Michael]

Thanks guys. And I apologize to everyone for taking so long with this.

I'm interested to see what the flow data will yield too. The more I look at this SN-4 impeller, the less convinced I am that it'll flow much more air than a standard or HO SN impeller. The spacing between the vanes is REALLY tight near their root. Even though the vane thickness is directly copied from the VR-4 impeller, they look tighter to me... it could be an optical illusion though. Maybe an 8 vane design instead of 16 (like the VR-4) will help to open the root area up a bit? Wouldn't be hard to modify this design to accommodate that.

I'm also contemplating a cupped vane design, similar to the vanes of HO SN impeller; a lot of modern superchargers and turbochargers use a cupped vane impeller design. It may help to yield more flow (and ultimately boost) but it would increase manufacturing cost. This design can be milled using a standard 3-axis milling machine since there are no undercuts. A cupped vane would require a 5-axis mill, which can get REALLY costly.

But I'm getting ahead of myself. I want to see what the CFD data yields first before discussing manufacture of prototypes and real-world testing.

Like I said, I'll keep everyone posted.

[Michael]

Welcome to the States, what part?

Thanks. It's nice to be here. :laugh:

I'm living just outside of Detroit, in Birmingham MI. Nice area/place, although it is all very new to me still.

[suede57ford]

Great work on the impeller. You are very talented.

I can't wait to see the results.

[zray]

Great work on the impeller. You are very talented.

I can't wait to see the results.

exciting work ! ! !

would love to be part of the testing.

Z.

[Duke]

I had a vr 4 on my 5.0 mustang since 2011. I ran it on the street. No problems. But do not I repeat do not run ford type f fluid!! Yeah run that you will be chasing rebuilds!!! I use amsoil supershift!!! Just read about it! It has way more friction modifiers than type f ever had!! And it was developed for high performance automatics at the drag strip! Well I did run typef till it turned black on me with 25 miles on it and made the balls chip. Well I rebuilt it myself and I was really upset with Craig when I called him and told him about the blower wouldn't turn at all after rebuilt. He said well that's why you should have sent it to us. I said we'll Craig. Guess what if you send race's that are .003 thousandths thicker than the old ones 6 thousandths total with both its not gonna turn!! Thank God I rebuilt it!! And type f I wouldn't put in my lawn mower! Yeah run type f so he can make money and rebuild your blower! Trust me it'd easy 3rd grade mentality!