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

           


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V-Rod Turbo

Milwaukee 8 Intercooled Turbo v. Non-Intercooled: A Reality Check
Paying $8,000 to $11,000.00 for a small Garrett GT22/25 turbo with a Thundermax ecm running maybe 7 psi of boost and 120hp is downright stupid. You might as well put in a 128 kit and be done with it and skip the non intercooled turbo keeping your right leg warm. 15 psi (2 Bar) 170hp with excessive inlet temperatures.

8 psi without an intercooler will heat the inlet temperature to 160F on a Summer Day.

If you up the boost to 12 psi of more without an intercooler the charge temperatures will be 200F or more. To see heat rise check our Intercooler Calculator.

See a 173 HP reality check below.


Reality: 2020 M8 Softail Low Rider S 
RB Racing 00-1306R Exhaust: 173 HP No Compressed Air
Customer writes: "I was very surprised by the sound level of the pipe. I have owned a LSR 2-1 00-1306 (no resonator) on a prepped Twin-Cam 110ci, and I must say this new pipe is incredibly quiet even though I run it on a 128cid with 11:1 compression. Dare I say « too quiet ? » ;-)

As I am used to LAF pipes, I was almost disappointed when firing the engine. But after a few miles running the bike I must say the sound level is just great.
Tone is very deep, and it will bark but won’t kill your drums when you open wide.

By the way, my neighbors thank you…

Performance-wise, the pipe seems really excellent, but I guess you need no feedback on this point !

I was aiming with this build 150-155HP. Engine is already shooting 170HP with a partial tune. Mid range torque is unbelievable. 
Ill be back with more precise figures as the bike gets fully tuned.

Update: And thanks for the new shield. Fitment is perfect.

128ci, 173Hp@5300, 194Ft.Lb@4300 (Engine figures), 30 tooth Belt Pulley.

Hang on! That ride is a blast !!!

Best Nicolas"

Milwaukee 8 Touring and Softail Turbo Kits Done Right

...up to 3 x Your Displacement in HP* (150 CID = 450HP*)
*With Fuel Pump Mods



New Advanced Turbo Kits for the M8

Note: M8 Softail /M8 Dresser...These are only done at RB Racing by appointment.

(1) Milwaukee 8 Full Race Systems..EFR

  


Back in the Shovelhead and EVO days we used IHI Turbochargers...150 to 300Hp.Then, later on, we switched to Ball Bearing Garrett GT Series rated at 360 hp and for racing up to 500 Hp.

With the M8's we have stepped up to the specialized Borg Warner EFR (Engineered for Racing) turbochargers that have a built in wastegate and blow off valve. These are about 100Hp more than the 360 HP Garrett GT28RS series we used on the Twin Cams and about the same Horsepower of the Large 500HP Garrett GT35RS we used on the Bonneville Bullett's 139" EVO motor we ran at Bonneville.

The blow off valve (BOV) is a very good idea. It will keep the turbocharger alive much longer. When you are driving the throttle plate is constantly being opened and closed. When the throttle plate is closed the turbo is blowing into a wall. This causes extreme axial load on the bearings, which will make the turbo prematurely fail. The BOV also keeps the turbo spinning while you shift from gear to gear keeping the spool-up time down between shifts.

No need for a $1,000.00 Thundermax ECM. If you want a Thundermax order it yourself. They are not legal in California.

The OEM integral wastegate insures reliable boost settings. Optional on the fly adjustment of boost.

8psi on the EFR is about 200hp....not 120. Think about that. 15psi passes 300hp.
 
We engineered a solution to up the sophistication for a M8 with 450+ hp potential (HP Capable to 3x whatever the displacement ) or a mild low boost 250hp. 136CID x 3 = 408HP (With Fuel Pump upgrades)

The only way your turbo motor gets air is through the turbo compressor housing...small compressor wheels and small air cleaners do not cut it.
(2) Milwaukee 8 Street Systems..Garrett GT


No burned legs. Intercooled. Large Capacity Air Filter. No Thundermax, Street systems up to 15 PSI. 50% of the capacity of our EFR Systems.


If you want a Thundermax order it yourself. They are not legal in California.

(3) Wrong Manifold Design

 

 

What you see above is a "Log" manifold where each 315 / 405 degree 45 Degree V-Twin exhaust pulse is directed to the opposite exhaust port, not directly to the turbo. Wrong.


Merge Turbo Collector...The Right Way

 

If you've done this hundreds of times it's a road well traveled. If you haven't, then it's a lot of expensive parts in the trash. Sliding bandsaw fixtures, high speed sanders and surfacers and a couple of deburring and checking operations later and you're ready to tig weld the high velocity merge collector. Each of the tuned primary tubes enter the slip portions and merge into what will become a 2" exit.

The exhaust pulses are individual events and the 2-1 merge provides the strongest signal to the turbine plus aides in cylinder scavenging to mitigate egr reversion. Straight out of World Rally Technology and what we have done on all Harley Turbos since 1980 beginning with Shovelheads.

Here the merge collector capped and purged with Argon. No weld burn through on the inside, just the mitered knife edges. No one ever looks inside, but we do. Exhaust tuning is terribly important with high output turbos. These aren't low speed diesel engines. Each pulse is an independent event but the high velocity merge sends strong signals back to the exhaust ports and the header length has enough elasticity (volume) to prevent shocking the turbine wheel with a coffee can sized sledgehammer pulses from the big bore cylinders.
Future Past...Act 4

Like it or not, the Twin Cams were dead at the MOCO post 2016 just like the Shovels were in 1985 and the EVOs in 1999. We've lived it all. 2017 onward it is all M8's.

Welcome to RDRS and variable cams. Pile on the complexity and add little or no education for the technicians and the owners...Give me glory, the bragging rights, I don't have time to learn anything new...social media beckons.

Six axis Bosch IMU's, high compression, dual spark plugs, 4 valves, torque based tuning, VVT CVO's and the same old weak rod / crank structure, with a gear-driven balancer and a heavy wet clutch floating unsupported in the primary..holy Batman! Add in a weak 6 speed tranny and a final belt drive to provide fuses.

The M8's are all going VVT and torque based tuning with multiple computer systems...ECM, Body Control CAN, Bosch ABS. It is going way past what shops can deal with. No brass jets, no needles, no throttle cables...just you and software.
If you Choose Wrong Turbo

Recently a customer from San Diego stopped by to buy one of our chain drive M8 swingarms...Turns out he had forked over $10,000.00 for an M8 Trask Non-Intercooled Turbo in Arizona and it turned out to be a slow rolling disaster and he quickly off'ed it to someone. The L.A. street racing scene is brutal. He wanted a turbo. He got a "turbo" and got his ass spanked but that's about all one could say.

We asked him some technical questions as to what the turbo configuration was, what he was told by Trask etc...It was a small, low CFM, Garrett Turbo that was rated at maybe 150 hp at 15 psi which they told him he could not run. 7 psi 120hp.

In short, it would never have worked for racing and what he was told by Trask about turbo size, boost, and fuel management made no sense whatsoever. It was only BS words to get him out of Arizona minus his $$$. What the hell, they got his $$$. In the local street racing scene here in L.A. word went out fast...Stick to built big inch m8 motors...and nitrous...skip poorly designed turbos.



Choke


If you think putting an air cleaner less than 1/2 the size of a stock air cleaner on your M8 turbo is a good idea...Well, logic got left somewhere while the plumbing was being done. Oops! forgot about front fender and wheel clearance. It's a choke not an air cleaner. Four of these on a Japanese inline four cylinder...it's a maybe a 50hp air filter...not even good enough for a stock M8. Lift the hood of your 250hp pickup and look at the air cleaner.

Heat When You Compress Air



M8's are about 240 psi Cold Cranking Pressure (TPS held open)...Add a turbo to heat and compress the air, without any charge cooling (Intercooler), and you have a questionable thermal equation. Think pumping up to 220F air into your motor with 15 psi of boost on a Summer day.

Use our Intercooler Calculator to see what happens to your boost inlet temperatures are with and without an intercooler

In 1992 we turbocharged an 80" EVO Dresser without an intercooler. Going two up the Grapevine here in CA (a long uphill stretch) the plenum was too hot at a constant 6 psi to rest your leg against. We then put on a 250hp intercooler (pictured above) and the plenum was barely a warm on the same grade. No free lunch, no more potential piston destroying detonation.

If you bought an M8 Turbo from someone with a small air cleaner and no intercooler well, at least you got a turbo. Park and talk,


It's all about the Airflow 

Cubic Feet per Minute or Pounds of Air Minute is what you add to accurate fuel delivery to make horsepower. You need to learn to read compressor maps before you even start to climb the horsepower ladder. Run the calculations on our Boost and Airflow Calculator.

See that higher inlet temperatures will require more boost to make the same horsepower. 



Tell Tale Indicating Boost Gauge (Mandatory)

 

Part Number 03-1013: 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. 1" or 1 1/4" bar mounts.


Center back mount w/12mm x 1.5 locknut and integral push-on hose nipple. On sequentially injected Harleys we 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.


Manual Boost Control (Optional)

   



Optional Black Knob: Rider controls the boost. Clockwise increases the boost. Turn the boost all the way off (full counter-clockwise) and it's about 6-7 PSI. For very high boost levels beyond 15 PSI we require you upgrade your fuel pump and regulator system. Just remember, 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. 6-7 PSI to 25 PSI. 15 PSI is way, way past 200 HP.

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


Single or Dual RSR Air Fuel Ratio gauges. Dual if sequential fuel injection.

Programming the Delphi Controller with TTS MasterTune you want to run near 14.7:1 at your light cruise settings for maximum economy. We run Race Plugs on the street and they are dead clean with a white porcelain. Using the Dual Air Fuel Ratio Gauge you can quickly get all transitions and F/R fueling correct...In the Real World.


Racing Turbo History:  Bonneville LSR and Drag Racing

Here's the 139 Inch Orca Bullett with it's large diameter stainless steel merge collector exhaust system and large air to air intercooler. Pretty much state of the art insofar as pushrod Dinosaurs go. Designed for the long course at Bonneville. 600 HP Turbo. 500 hp @30 psi on this 139" engine. In testing we have run 212 mph @ 4700 rpm with 9 psi of boost. At the Salt we did one brief test at 19 psi and 350HP (2.5 x CID).

It only runs a couple of minutes at a time...not much time to insure it is safe. It has passed all SCTA-BNI and AMA/FIM inspections and Bryan Stock, filling in for Mike Geokan, has got all three licenses 150, 175 and 200 mph and is cleared for long course at Bonneville.

With Brother Speed's Bryan Stock in the seat it held a 200 mph record at Bonneville in "low boost" testing. We held Bryan to 4800 rpm to let him get a 200 mph SCTA-BNI record. It has run 214 mph with just 9 psi of boost. Next step up was installing more advanced electronics with FBW and Traction Control and 230-250 mph. We briefly ran the bike up to 345 hp but course conditions were terrible. The salt is gone.

We left the project, removing our Pectel Cosworth SQ6M electronics in 2017. No one wanted to test...just attend.

Mike Geokan's RB Racing Turbocharger used a separate oil system we engineered that has a stainless steel oil tank and an electric feed pump that maintains a constant 25 psi to the Garrett GT35RS ball bearing turbocharger. The engine ran 50 weight PennGrade1 (ne Kendall) "Green Stuff" oil and the turbo runs PennGrade1 20-50W.

Black Strips Lasting Longer Than 6 Miles

If you experience black strips lasting longer than six miles seek immediate mechanical attention and replace your RB Racing Turbo. Continued use can cause loss of licenses, premature tire wear, and infuriate your competition. Bonneville Salt Flats...where we prove our products...and have nearly 40 years.

Mike Geokan's Bonneville #226 Harley...Since 1991 RB Racing Turbos


Back around 1985 we met Carl Pelletier, Mike Geokan, and Bryan Stock at Bonneville and was asked to Turbo a Harley for them. We blew them off. Around 1991 we agreed to turbo Mike's 104", Carl Pelletier built motor...if they brought it down to California. They did. We did.

Can you take your 250 hp Harley race bike and cruise around to thank the people who have helped you set records? It takes a lot of people to build a bike from scratch and to support a race effort.... Painters, welders, fabricators, engine specialists, fellow club members, and even professional dancers like Salina. You never do it alone and if you don't take the time to thank those who helped out it's going to be a cold lonely night with you and your time slip to keep you warm.

Salina moved on long, long, ago...you can't feature dance forever.


Bullett Test Vehicle: Chronolgy

Mike was running 199 mph in Bonneville Slush with 22 lbs of boost and 275 horsepower way back in the early 1990's. These days Mike's attention is devoted to his 139" RB Racing ORCA powered Bullett.  He can't ride it due to health issues.  His friend of 50 years Bryan Stock has taken over the riding chores after we rode it 4 times, two illegal and two down the short course to the 3 mile marker.

In 2017 we bid farewell to the Bullett Project. Mike was finally well enough to go to the Salt and opened up his ugly take on the world. One's true nature always comes to the front sooner or later. What the hell..It was fun with Bryan and the crew and we got Bryan and the Bullett a 200mph record.

Mike can now pout, scowl, and keep getting people to pay for his project while he putters around watching TV, eating out twice a day, and talking about the distant past through rose-colored glasses...saying he does not want to learn anything new post Panhead technology.

Mike Geokan's world record holding RB Racing Turbocharged Harley Davidson is featured in an old video.

It still runs with our 4 injector RSR EFI 32 years later...and Mike has no idea what the programming is.


Turbos are a complete system

A complete systems approach is why our RB Racing turbo kits produce so much power at low boost levels and why they work so well in day to day operation while giving excellent fuel mileage and drivability. More often than not people come to us after spending some astronomical sum of money on their engines only to be disappointed in the result.

When we tell them they have to start over with different pistons, cams, gaskets etc they reply that their motor will be just fine turbocharged at 10.5:1 compression ratio and 15 pounds of boost. Since everyone is an expert we no longer try to advise them differently if they so object...Everyone has to learn sooner or later. We do recommend 8.5:1 if anyone wants to listen...of course this all depends on cams but that is another story all together.

When you purchase an RB Racing turbo system we ask what your intended use is and structure our advice based on the latest information we have. Look at the early RB Racing turbos in the links at the top of the page to see how far we have come in 44+ years.


7 Second Old Pro Gas Design...Way More than Two Decades Ago

This Pro Gas 500+Hp system was custom built for a Pro Gas race application and involved fabrication for intercooler mounts etc. at the builder / fabricator level. The Pro Gas system pictured below was built for National Modified Champion Wayne Pollack of Fuquay Varina, North Carolina. Wayne flew out to see us and agreed to build a bike around the system we would design instead of vice-versa.

Wayne wanted to build a sophisticated Turbo bike but he made the serious mistake of ordering some cylinder heads from Nigel Patrick who did zero, zip, for a year after he took Wayne's money. The year delay caused Wayne to miss a complete season and his sponsors cut the purse strings and his "crew" dispersed to other projects.

Wayne donated the parts to Ken Browne, who continued with the project, but cut up the parts and left off the 500hp intercooler. There went 1% in hp for every 11 degrees F the charge cooling would have provided. Those of you unfamiliar with how much air heats when you compress it...at 22 psi the discharge temperature can be 265 degrees F. You can't find any turbocharged race vehicle without a large charge cooler.

Ken won the Pro Gas Championship.

Ken still managed to run 7.55 @ 173mph (176mph best mph) in the quarter mile and 4.80 @ 147mph in the eighth mile, and built a new bike with a bigger tire!

Ken's new bike is (2002 - and later) was further away from "what should be" and didn't work well. More weight, poor turbo location etc. Ken is a nice guy, but bad ideas, no matter how nicely executed, simply won't work. We talked to Ken, hoping he would just execute our original design, but everyone wants to do "his own thing". There is always a price for this. Hey! It's not death..It's a hobby!. Hey, he's even built a third one. Ken had to quit riding after a not too successful neck operation.

Wayne Pollack went on to wrench and ride the beautiful Majestic Turbo bike, initially with twin turbos (didn't work well) and later on with one very large turbo similar to the one pictured. We sent Wayne the turbo specs and drawings for a new design so he could shit-can the two turbo deal that Kevin Draper and Don Vesco cooked up. Wayne got to deal with methanol and Hilborn injectors with nitrous added to the mix. Boom! Blow up an Overkill Engine.

Wayne was always straight with us, he's a hard-core racer and like Wayne, we think there's nothing much better than kicking ass and trying to be the best at what you do...Wayne went off to ride Ray Price's Top Fuel Harley and to stay in shape just ran a 242.587 mph World Record ( Sept 2003) on Rich Yancy's turbo Hayabusa at Maxton. In 2005 Wayne upped the Maxton record to 258mph on Rick Yancy's Hayabusa.

Here's Wayne on Ray Price's Top Fuel Harley (Oct 03). Ray got a bit banged up and Wayne was tapped for the ride. In August 2004 Wayne retired with back problems...no more spine crushing acceleration. Wayne went on to set a speed record of 258mph on a Hayabusa at Maxton in 2005.

We get a few calls each year about Pro Gas systems. We suggest you call us before you start building. Everyone wants to do their own thing but decisions can haunt you and they get expensive. Click on the below pictures for more details on these parts and people.

RB Turbos: First Fuel Injected Harleys in the 9's, 8's and 7's..RSR EFI

We've been at this for awhile from our early 80's 150hp Shovelheads up through our 360 hp TC and EVO Turbo Kits . We put the first fuel injected Harleys into the 9's, 8's and 7's at the drag strip. The only fuel injected intercooled Harleys to hold a national drag racing championship and Bonneville records come from one place..RB Racing.

Whereas people love to talk about about turbos and, if they have touched one once in their life they become experts, we have been at this long enough to know what should be done and what the difficulties are. It's always amusing the see the poor engineering that comes and goes in this market. It's not about plumbing and band-aids.


Ken Browne's original record setting 120 cubic inch 4 cam Pro Gas bike. RB Racing Pro Gas Turbo / RSR 400i Fuel Injection System. Best 1/4 mile E.T. 7.55; best mph 176. This gives you and idea of how much power is hiding in our systems. Pro Gas Champion.


Final Point

People who don't do this for a living have all sorts of advice. They specialize in being "persons of authority" even though they have not done the work. They give advice about cams, turbo design etc. and they can't walk the walk. There is more bad, incorrect, crap floating about turbocharging around than there are turbos running. 

We've been at it for over 40 years and, since we actually make the stuff, we know even how little we know...which is a lot more than those who don't do the work. We aren't here to correct misconceptions, only to support the art.

Take a 203 mph pass on the Bullett.

Bonneville 200 MPH Record Pass ... 139" Bullett


Make no mistake about it, when you deal with the big twins you are dealing as much with art as with science. Everything is hanging out in the open for everyone to look at and it is extremely difficult to blend function with aesthetics, especially in this era when every other bike is a "show bike" with every piece of billet trickery and chromed what nots glued or bolted to every exterior surface. 

We think our new M8 turbos will meet the most demanding needs of any big twin whether it is trailer bound for the next show or caked in wet salt on its final record pass at Bonneville.

We will not compromise functionality however...so don't ask.