Yaris GR Dyno Testing continues, RS Fabrications development.

Dyno Testing continued this week with further exhaust development.

A replacement 200 Cell Sport Catalytic Converter was installed along with other downpipe modifications.

Running the Twin Silencer, Twin Exit RS Exhaust System along with DTUK Tuning Box and ITG Panel Air Filter results were very encouraging.

Various maps were tried with runs consistently producing 310, 311 & 310 BHP figures and Torque figures of 429, 430 Nm repeatedly.

“The Yaris GR 310 has arrived” commented Russell “Considering when we started development with the Standard Yaris, it was running 265 with BHP 400 Nm of Torque. we have made really good gains in a relatively short space of time, culminating in the 310 BHP and 429 Nm of Torque this week. This shows a 17% Performance Gain over Standard which we are really happy with.”

Final runs of the day were completed with the 3.0″ Single Exit Silencer [Race Specification] as previously tested. No further gains were seen with this set up, but a different Exhaust Tone and higher dB recordings were experienced. It would appear that the Police were also interested in the Single Exit Silencer!! but luckily not for the same reasons.

A lower Rear Bumper Panel/Diffuser is currently being modified at RS Fabrications, Towcester, with an insert panel to fill in the RH exhaust aperture. This modified Panel will complete the single exit installation, details to follow:-

As Russell said,

The Yaris GR310 has arrived!!

RS Fabrications Yaris, addition to the Family. GReat News

Another exciting week with the arrival of a second Toyota Yaris GR.

RS12 FAB [Big Red], a welcome addition, that will double RS Fabfications development time.

RS12 Fab was immediately put on the 4 Poster Lift for the full RS Fabrications Performance Package, Twin Silencer Exhaust GR-RS 100 [The Gentlemen’s] with Carbon Tailpipes, Tuning Box & Replacement Panel filter [ITG Prototype] bringing it up to the full 300BHP specification. Additional Tumbling “RS” branded side stripes finished off the package. [RS Filters to follow]

” This gives us potentially 2 avenues of development and testing” Russell said. “Invariably one of these vehicles will be in the workshop at any time in pieces. We are constantly working and trying to extract the ultimate performance from the Yaris GR. The Vehicles give us 2 ‘Test Beds’ for back to back and Comparative Testing.” 


As manufacture on Exhaust System increases, additional tooling has been manufactured to help with production effectively doubling production. Additional fabricators have been drafted in to help with the workload. The only downside in manufacture are the increased material costing from companies in Europe. Stainless Steel costs have been increased by 20% from last years pricing alone and unfortunately has a knock on affect.

Here is the revised current RS Fabrications Product Pricing:-

GR-RS 100          Centre Section Silencer + Rear Silencer                 85 dB          £1884.00

GR-RS 101          Straight Through Centre + Rear Silencer                90 dB          £1644.00

GR-RS 102          Centre Section Silencer + Rear Straight Through    92 dB          £1464.00

GR-RS 103          Straight Through Centre & Rear Sections               95 dB          £1224.00

GR-RS 104          Single 3″ Exit Silencer + Centre Silencer                                  £1674.00

GR-RS 105          Single 3″ Exit Silencer + Straight Through Centre                     £1474.00

GR-RS 106          Single 3″  Exit Straight Through + Centre Silencer                    £1274.00

GR-RS 107          Single 3″  Exit + Centre both Straight Through                         £1074.00

Carbon Fibre Tailpipes              £150.00 Pair

Mirror Polished Tailpipes              £75.00 Pair

Stainless Burnt Tailpipes              £75.00 Pair

3.0″ Straight Cut Tailpipes            £75.00 Pair

Fake 3.0″ Tip for Side Exit RH       £75.00 [Single Exit Exhaust Only]

Exhaust Fitting                             £70.00     RS Fabrications, Towcester

RS Air Filter [ITG]                         £37.50

RS Tuning Box & App [DTUK]        £420.00  [Includes RS Fabrications Tuned Maps]

Tuning Box Installation                £100.00

Tuning Box Mount                         £40.00

Post & Packing:-

UK                                                £50.00

Europe                                        £150.00

All pricing subject to VAT

For any further Information contact:-

RS Fabrications            01327 354445

Russell                            russell@rsfabrications.com

Sarah                               sarah@rsfabrications.com

Yaris GR Performance Project, Update Week 6, Customers & Development

The RS Fabrications Yaris GR Performance Project continues to expand, rapidly!!

Production, Sales, Shipping, Customer Vehicle Installation and continued Research & Development makes for busy times at the RS Fabrications Workshop.

First up was Adam this week, car enthusiast from Warwickshire he currently owns various Performance Cars, most noticeable being a his immaculate Lancia Intergrale. Adam understands Performance Engineering & Fabrication and booked his Yaris GR in for the full RS Fab Package.

Adam opted for the GS-RS 100 Centre Section Silencer & Rear Silencer [coined “The Gentlemen’s Exhaust” by The Duke] with Mirror Polished Rolled in Slash Cut Tips, along with the Tuning Box, Tuning Box Mount, and RS [ITG] Performance Air Filter.

Meanwhile, the RS Fabrications Yaris, RS70 FAB, has been back in the workshop for a 3.0″ Single Exit Rear Silencer upgrade, in combination the the current 3.0″ Centre Section Silencer. Interesting difference in sound and further development is required along with a 3D printed infill panel for the RH aperture in the diffuser section of the rear bumper.

Along with  our current Yaris GR Performance Exhaust Range, Qty 4 Different Systems, this brings the RS Fabrications Exhaust Options List up to Qty 8 different set ups to suite any application and personal taste. We cater for different levels of noise over the range.

Yaris seen here in Test Condition, further Dyno and Road Testing is planned on this Single Exit System. N.B. this Rear System can be run with or without Centre Section Silencer.

RS70 FAB is back on the Rollers this week with further Exhaust Development, of which components are currently in manufacture at RS  Fab, Towcester, updates to follow……

Duke of Marlborough, Toyota Yaris GR 300 BHP Performance Upgrades,

Interesting start to the week with the Duke of Marlborough bringing his Toyota Yaris GR to RS Fabrications for the full RS Fabrications Performance Upgrade.

Full Stainless Steel Cat Back Exhaust with Carbon Fiber Tips , DTUK Tuning box with RS Fabrications Map [developed on the Dyno], and ITG Panel Air Filter. The Duke also opted for the RS Fab side stripe package.

“I met up with the Duke last week when he came to RS Fabrications to drive our Development Yaris” commented Russell, “We appear to have some common ground and James understood the detail and finer points of precision fabrication and quality” he continued

He arrived Monday with his Yaris GR, that was only delivered last Friday, and the installation Started with Ben 10 taking on the Exhaust Install duties on the 4 Poster Vehicle Lift.

The Prof, [Michael] RS Fabrications Tuning Consultant, performed the DTUK Tuning Box install and loaded the same files [RS Fabrications current Map] onto the Tuning box.

Identical specification to the RS Fabrications Development Vehicle the prototype Induction Technology Group Panel Filter [as previously tested] was put onto the Red Yaris, as the RS Fab Branded Panel Filters are in manufacture at ITG, Coventry.

  Development continues on the Black RS Fab Yaris GR this week and the Vehicle will be back on the Dyno later this week with additional performance & development components.

Next week the second RS Fab Yaris GR vehicle arrives, in Red this time, so that the RS Development Program can be accelerated.

Russell and the Prof have an extended list of Research & Development improvements that have to be applied to both Vehicles, doubling the ability to bring New Product to the rapidly expanding Toyota Yaris GR Market.

Exciting Times lay ahead!!

Please Contact Russell or Sarah if you have any questions regarding the RS Fabrications Yaris Performance Project on 01327 354445 and get further up to date information.

Yaris GR Performance Exhaust Production and Customer Fitting continues.

Yaris GR Performance Exhaust production is flat out at the the RS Fabrications Workshop, Towcester.

Orders from UK, Belgium, Greece & Switzerland have been fulfilled, with enquires received from Australia, Italy & France. A steady stream of collections and fitting components “in house” continues.

“It’s difficult to keep up with demand at present” said Russell “and Monday we have the Duke of Marlborough returning with his GR for the full Monty, we had previously been out in the RS Yaris! I think he’s recovered!!”

The Duke, James Spencer-Churchill arrived at RS Fabrications for a drive and was so impressed with the performance gains on the RS Yaris Package, and the workshop facility, that he booked his Yaris GR in on the spot. Details to follow on Mondays installation.

Covid19:- Obviously, Face Masks and Social Distancing was maintained at all times.

Some material supplies have been effected by Brexit, mainly cost, but generally supplies have been forthcoming to maintain Production.

Customers arriving, Face Masks and Social Distancing again, and the RS Performance Package installation begins.

Exhaust Options chosen and fitted, DTUK Tuning Box and ITG Panel Air Filter Installed. Fake Exhaust noise turned off and up to date RS Maps loaded. 2 Hours Installation Time and all good to go. Note RS Maps are constantly being updated as development continues.

For further information and bookings call Russell or Sarah on 01327 354445

Suzuki XR69 F1 TT Aluminium Swinging Arm

Local Silverstone Bike Builder, John Simms at Trident Engineering, came into RS Fabrications with a simple request. “Russell, Can you make me some of these XR69 swinging arms?”

” No, problem!!!” was Russell’s reply. [“as always” Sarah added!]

Working from a sample Swinging arm, manufacturing tooling was designed and fabricated in house, mainly from 20mm Aluminium Tooling Plate and various Machined Mounts and Components.

Work began on the Prototype Swinging Arm, from the new tooling.

Specific Box section Aluminium had to be manufactured in house, folded and seam welded to specific dimensions. Other machined components were CNC machined.

Once the Prototype had been completed, and finished machined, the swinging arm was assembled and fitted into a customers XR69, in build at Trident Engineering, Silverstone.

With confirmation on final fit from John, a production Run of a further Qty 4 Units have been completed to the highest quality at the RS Fabrications Facility, Towcester.

Another fine example of Precision Engineering and Fabrication from Russell, Sarah and the Fabricators at RS Fabrications during these testing Covid 19 Pandemic times.

For further details contact Russell on 01327 354445

RS Fabrications Yaris GR Dyno Runs and Production

With research, Russell invested in the DTUK Performance Specialists Digital Tuning Box for the Yaris GR and with another exhaust change it was off to the Dyno, Testing.

Time invested on the Dyno has produced great results for Exhaust Tuning and Mapping of the DTUK Tuning box.

Maps have been specifically manipulated for RS Fabrications and their exhaust design and configuration, in a joint partnership between RS Fabrications & DTUK.

These Maps will be exclusive to RS Fabrications and with DTUK support further testing will be taking place in the future as development continues with the RS Fab Yaris GR.

With a long association with MRC Tuning, results show that is was time well spent.

Russell & Doug ran the Yaris GR, producing 12% gains over the standard Baseline Test that was completed at the end of last year.

Gains in overall power and torque [drivability] were achieved.


Call Russell for Current Pricing on 01327 354445  russell@rsfabrications.com

RS Fabrications, R & D, Data Collection and Analysis

“Probably the most interesting time that you can have with any vehicle is on the RS Fabrications Yaris R & D Testing Program” commented Russell recently.

Outright performance & vehicle improvement is the goal, with additional Testing and Analysis under strict Covid rules in these difficult times, but they are making headway!

Also we have been Dyno Testing Today. Results to follow………………

Yaris GR, RS Fabrications Evaluations

With evaluation runs out between Christmas & New Year, Research & Development continues at RS Fab.

From our original Test Sessions and further Road Testing our 0-60 time have dropped from  5.01 to 4.40  and our 30-70 times from 4.78 to 4.20 both on a damp cold morning but still showing some superb gains. [N.B. On a dry road we would expect the 0-60 time to drop from 4.40 to 4.20]. Further Development will continue back at the RS Workshop.

With another Dyno Session booked for this week the Yaris is back on the ramp tomorrow. Next item is the Airbox along with some additional exhaust tweeks and dB Noise Evaluation with the different Performance Exhaust options that are available.

For further details contact Russell on: 01327 354445 or russell@rsfabrications.com

Yaris Testing and Exhaust Manufacture continues at RS Fabrications

Exhaust Testing and Manufacture continues at the RS Fabrications facility in Towcester.

After testing with our straight through system on Track we proceeded to MRC Tuning, Banbury, for Dyno runs.

With limited time, we tested the Standard Yaris Exhaust System for a baseline and then tested our GRS 102, 3.0″ Centre Section with Silencer and Straight Through Rear Section 3.0″ into Twin 2.5″ Section.

Standard System produced 265-269hp and the subsequent runs with the RS Fab System produced 278hp. Good gains with the initial RS System along with actual sound.

Picking up 10hp was great and power gains were apparent through the rev range.

Further tuning and comparative test is schedule for Jan 2021, particularly the dB figures for each of the Qty 4 Performance Exhaust Systems GRS 100, 101, 102 & 103, to cater for all customer requirements.

Factory Fake Exhaust Sound & Noise Cancelling

The production Yaris GR has fake exhaust sound piped through the speakers into the cabin of the vehicle, ESE Engine Sound Enhancement and ANC Active Noise Cancellation.

It seems that the fake sound was interfering with the RS Fab Performance Exhaust sound and the noise cancellation was trying to cancel the new exhaust sound too!! This was creating a strange sound effect from the speakers.

Both the ESE and the ANC have now been turned Off, and the strange effect has been removed leaving a superb sound from the new performance system.

N.B. With the standard exhaust and the ESE/ANC turned off you can hardly hear the exhaust at all when driving the vehicle.

Customers:- Please remember to take advantage of the additional 10% discount on orders place on or before 15th Jan 2021.


Sarah or Russell on:-01327 354445 or