PMB Performance - Project 914 ORV!, Yup, we're building a 914 for Utah's backcountry... Options

[Eric_Shea]

Gotz ta get all the parts before ya can start bolt'n them on! (IMG:style_emoticons/default/huh.gif)

[DavidSweden]

The work your doing looks very nice.

I have a question regarding the rear bushings; in your opinion would it be workable to use a metal bushing instead of the poly?

[Eric_Shea]

Thank you!

Regarding the bushings - You bet. The Elephant PolyBronze units are some of the finest metal bushings on the market. We sell quite a few varieties:

http://www.pmbperformance.com/914suspension.html

They're actually more of a journal bearing with a inner spiral grease journal. VERY good quality stuff.

I'm using our PerformancePoly front and rear (yes, we now have fronts here at the shop) to validate their durabillty. Again, the softer durometer bushings have tainted the market so, this is something I wanted to do for many reasons.

I think the off-road platform is a perfect place to prove these out. The company that molds these for us does all of the hard bushings for the Jeep and 4x4 off-road market.

[tomeric914]

Don't confuse what Eric sells with the Weltmeister crap, it's not the same! Eric's Delrin bushings are far better. They do require machining to set up right as he has shown. If you don't have access to a machine shop, then spend a little extra coin for the Elephant bushing kit which are pretty close to plug and play.

Years ago I made the mistake of buying the Weltmeister bushings. They lasted about 6 months. (IMG:style_emoticons/default/barf.gif) The Elephants have been in my track car for 4 years now with no problems.

[Eric_Shea]

We can machine them for our customers as well:


https://www.youtube.com/watch?v=pkIUODfyNkY

[euro911]

Hey Eric, if going with the delrin/poly type, do you need the customer's pivot shafts to accurately machine the bushings?

[DavidSweden]

Regarding the bushings - You bet. The Elephant PolyBronze units are some of the finest metal bushings on the market. We sell quite a few varieties:

Yes Elephant have good products.
I was thinking it would be fun to turn some bronze bushings myself, if I were to go this route what would be a reasonable clearance between the bushing and the axle and is bronze the best material?

[Eric_Shea]

We used a micrometer to measure the shaft(s) at their thickest points (in the middle where there is no wear). You'd have to play around with the bronze to check your final fit. The arms themselves are not always a perfect fit so, what may look good on the shaft itself can change once inside the arms.

This goes to Marks question as well. When measuring 4 separate shafts, we found them to be consistent. That said; they do tighten up considerably when installed in the arms. I found that to be perfect. That's exactly what I wanted. Once in place, I could not turn them by hand. Once I torqued the outer mount on and greased them, I could turn them with the leverage of the outer mount. Now... once a car is riding on them, I expect that to be perfect. I'll be doing the same thing with the fronts along with conical washers all around for a bind free fit.

I'm not sure turning my own bronze bushings would peg my "fun-o-meter" but if I were to do it I would try some of the oil impregnated bronze as a starting point. The "Poly" surround on the Elephants relieves a lot of frustration you'll have with the arm fit and they come with new shafts etc. If you take the six major pieces in the Elephant kit and divide out the cost, for a little over $50.00 each piece, time, labor and materials can easily exceed the cost of two (or three) Elephant kits. (IMG:style_emoticons/default/biggrin.gif)

[ThePaintedMan]

I used PMB's bushings and installed everything just like Eric outlined. Though my measurements and fitting weren't quite as precise as his, I am thrilled with them. We did 10 hours of track time on them at Sebring and at the end had a little squeaking. A couple of shots of grease in the fittings and they went right back to being dead silent. Great product!

Eric - glad you've done the fronts now too. Any chance those will be available for us to purchase?

[euro911]

I musta missed something ... why was the JB needed?

(IMG:http://www.914world.com/bbs2/uploads/post-1110-1418272771.jpg)

[Eric_Shea]

Eric - glad you've done the fronts now too. Any chance those will be available for us to purchase?

Hey George, Thanks.

Yes, I'm going to get a set of arms and run through a few "Best Practices" scenarios before I launch them onto the market. I need to get ID measurements correct and LOA with both bushings loaded in their respective end caps and on the car. I have all of the conical washers as mentioned earlier as well. I want to perform a full non-binding install and get pictures and make notes.

Mark, these are very hard bushings with little give so, they can't be made to "force" into the arm like the softer ones. Some fit very tight and some are snug. You want the bushing to remain stationary in the arm while the arm itself rotates on the shaft. The shaft has to remain proud of the bushing end because it gets torqued to 85-87 ft lbs. on the outer side with the mount and 108 ft. lbs. on the inner suspension ear. Those knurled ends dig into the body mounts and figuratively make the shaft one with the body while the arm rotates on the shaft. Any excess side-to-side movement and you'll get slop, noise and odd handling. Any looseness on the shafts and you get rattles and squeaks.

"Most" bushing installs require JB Weld to either install their precise races (Elephant) or their bushings in general. It's those variances you mentioned in your previous post that need to be overcome and with these rear arms, I've found the arms themselves to have the largest variance.

Elephant has a nice method of supplying a sleeve that is a looser fit to the arm (like these) and then makes the arm precise to their bushing ID. That sleeve needs to be JB Welded on though. I may utilize sleeves for my fronts. Still thinking my way through it. The variance, again, will be the arm itself. Some may be rusty stock old paint "get'er on the road" fixes. Some may be powder coat. Some may be paint. That's where the sleeve can come in handy. "Do what you want but, put this on before you put the bushing on..."

[r_towle]

I musta missed something ... why was the JB needed?

(IMG:http://www.914world.com/bbs2/uploads/post-1110-1418272771.jpg)

Venture a guess that it is there to hold the bushing in place while you drill, tap and fit the zerk grease fitting.
You don't want the bushing to move inside the trailing arm, you want the bushing, and trailing arm, to move around the shaft.

Rich

[euro911]

OK, got it.

[ThePaintedMan]

I'm ready for a set of those front bushings. Just sayin. (IMG:style_emoticons/default/poke.gif) (IMG:style_emoticons/default/biggrin.gif)


Hope you do end up doing the cross-country trek Eric. It would be fun to meet you at Amelia!

[Eric_Shea]

I think the trip is in pen.

I have the fronts and a reamer coming for the lathe. (IMG:style_emoticons/default/wink.gif)

[tomeric914]

Any ORV update pics? (IMG:style_emoticons/default/smile.gif)

[OU8AVW]

Yeah, seriously Eric, starting a great thread, putting it on the classic builds page then leaving us hanging with no exciting pictures.....
LAME! (IMG:style_emoticons/default/dry.gif)

(IMG:style_emoticons/default/biggrin.gif) Get back to work!

[siverson]

I beat you to it! (IMG:style_emoticons/default/smile.gif)

-Steve

[JmuRiz]

...with the kid seat = bonus points!

[sixnotfour]

I beat you to it! (IMG:style_emoticons/default/smile.gif)

-Steve

Love the Irish Green and Mahle's