RB Racing Turbos...Big Twins: Shovels to M8's (Click on Image or Text Below)

           


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V-Rod Turbo

RB Racing Turbo Kit Shovelhead History

Ancient history as it is said. We started developing these Shovelhead Turbos before 1980 when a very small IHI Turbocharger, the RH05, became available via George Spears of Shelby Spearco who we knew via our Los Angeles automotive racing contacts dating back to 1974. Rajay Turbos were too big.

We settled on an SU Carb (HIF6) in a draw through configuration with a RHO5 IHI Turbocharger. We tested for about a year trying to make the turbo and the plumbing live for 100, 250. 500 and eventually 1000 miles. This involved in multiple upgrades to the turbo internals as well as the exhaust and inlet hardware. We even developed a custom SU needle that was made by SU in the U.K. We modified the SU for the turbo.

Rivera Engineering's Mel Magnet, the SU supplier saw $$$ and said he wanted 100 turbo kits...We made the first deliveries and then things ground to a halt. We did one brief turbo road test at Rivera with Randy Snyder who we warned the bike was fast but would not stop. Randy found out that was a fact. Money was owed.

A phone call from Woody Harrah (Pacesetter) informed us Mel was having our kits copied by Kas Kastner. We knew Kas and visited his shop and there were our parts on the floor. We told Kas to go for it and mentioned something about sleeping with snakes. Kas really just wanted to go sailing. Cool guy.

We had to get a bit forceful to collect our money from Mel by locking him in his office and clearing his desk, at Whittier Harley-Davidson where he sublet space.
 
The IHI RHO5 turbos were obsoleted by 1984 and the IHI RHB5 that replaced them was not suitable for Harleys as it was way, way, too restrictive.

Shortly thereafter in 1985 Mel from Rivera came back to us saying they had made a big mistake screwing us over and wanted to work with us on turbos. We got even (no details).

Mel moved on to rip off the Primary Belt belt market via an ex employee of a belt drive company who Mel, in turn, screwed over.

Next the IHI RHB52 came out an we transitioned to a Shovelhead Blow Through Carb Design. However, Shovels became a dead issue as the EVOs came out.. We moved directly to the EVOs and dropped any further Shovelhead Turbo development.

Note: Shovel Turbos can only be done at RB Racing at present...Too many variations. Several approaches. Only one is right. Call.
RB Racing Turbo Shovels..Circa 1980/81

Models: Shelby Sawyer. Harley FXWG

The first successful turbo for the Harley big twin was our design which featured an IHI Turbo, a draw-through SU CV Carb, equal length primary tubes joining into a 2-1 turbo header; a 2 1/2" turbo exit pipe with a 3" diameter turn-out muffler.

The RB Racing kit featured an RB Racing billet Boost Master wastegate, a chromed inlet plenum, and a glycerin filled boost gauge. These kits produced 125 to 150hp @15psi of boost.

No heat on your leg with exhaust routed forward

Some 25 years later Shelby got in contact with us and we got her some prints of the photo shoot. She was at the audition for the shoot with a friend and did the shoot after another model sort of dared her to give it try. Pro photographers Mark Rice and Ron Tuso did the shoot. Small world. Shelby is doing fine these days, involved in religious art.

RB Racing Shovelhead Turbo

 


Some kits were produced with black chrome headers

The black chrome pipes indicate this was one of the first 33 units we produced. Draw through SU Carb. BDK Needle 101.5 main jet, 2 1/2 turns out...can't seem to forget that for some reason. Actually there are a lot of reasons we can't forget that. These were the first successful Harley-Davidson turbo kits. If you ran them up to 15 psi and worked on the engines they would produce up to 150hp...Of course you couldn't stop but that was another story.

We even built, in his shop, a turbo for Dick Evalesky of Atlas-Precision Frames (closed /retired) for a big money grudge race that he won. Testing against a CB750 his Chopper would thunder by after the CB750 got it out of the hole.

Mechanical Boost Gauge

 

3 Bar Boost Gauge with Tattle-Tale indicator showing maximum boost actually run. Glycerin filled to resist vibration. Easy to reset, even with gloved hand. Not lighted.

Part Number 03-1013: Center back mount w/12mm x 1.5 locknut and integral push-on hose nipple. On Harleys you can mount this gauge directly off of the back of our RSR Dual Air Fuel Ratio Gauge. Viewing the tach, the air fuel ratio, and the boost all in one location. Only O2 feedback is fast enough for real-time monitoring.


Boost Control (Optional with External Wastegate)

   

Black Knob controls the boost. Clockwise increases the boost. Turn the boost all the way off (full counter-clockwise) and it's about 6-7 PSI.  Just remember, leaving it set at 8 psi, you can outrun about anything. When you're cruising at 75 mph and roll the throttle on it will instantly produce boost pressure. Rider adjustable when you are riding.

Turning dial up to 11 turns: 6-7 PSI (Wastegate Spring) to 25 PSI.

Dual RSR Air Fuel Ratio Gauge is to the right. We have no idea how anyone thinks they are going to get their tuning right without actually riding and observing the Single or Dual O2 Display. The O2 Display is a mandatory purchase with the kit.

Barely nudge the throttle and it goes to 0" Hg and anymore than that and it goes directly into boost. Hit a long steep grade at high speed and the turbo will hold at about 2 psi boost. It's not a good idea to beat your bike to death on a dyno if there is not enough airflow especially with a turbo. Best to ride.


Single or Dual RSR Air Fuel Ratio gauges. Which one depends on the system or rider preference.