Anyone tuned their Mk 3.5?
Discussion
Just wondered if anybody had done any tuning to the Mk 3.5? There doesn't seem to be much available for the car beyond a Milltek exhaust system and induction kits..... Do any reputable companies offer engine upgrades? The Cosworth supercharger kit for the MK3 seems to have died a death due to reliability issues......
Richyvrlimited said:
daveknott5 said:
The Cosworth supercharger kit for the MK3 seems to have died a death due to reliability issues......
Freely available from BBR GTi still?!?There are numerous NA tuning options for the Duratec engine which if you google you will find - not cheap though.
Had the conversion done in September last year, had the car on a rolling road before and after and the figures that BBR issue stack up. Had a problem after about 1000 miles with the car, very occasionally, stalling from cold in negative ambient temperatures. BBR had the car back and haven't had a problem since.
Neil at BBR was great with my endless questions before getting the conversion done, it is a lot of money but I haven't had the problems previous Cosworth converted cars have had. Neil has done quite a few conversions now and I've yet to hear of a problem car.
I've measured the fuel consumption over 2000 miles and have averaged 31mpg. Highest figure is 34mpg lowest is 27mpg. My drive to work is A and B roads all twisty single carriageway.
I’ve found that you need a couple more revs to pull away but it’s something you get used to. Neil says to turn the ignition on, wait 2-3 seconds for the BBR ecu to ‘shake hands’ with the Mazda ecu. In reality I forget to do this most of the time and its fine.
On turning the key to start it takes a split second longer to fire. S/C whine is not intrusive, I don’t really hear it unless doing a hard accel. On the mk3.5 the noise tube in to the cabin is removed, but that doesn’t bother me.
Driving the car is fantastic. I usually get bored with cars and change them after about 6-8 months. I‘ve had this one over two years now and it always brings a smile. Apart from the things highlighted above it behaves exactly the same as a standard car until you accelerate. It pulls hard and makes overtaking easy. With the standard car revving the up to about 6.5k seems to take ages with the S/C the needle flips round. I took some video (iphone) before and after S/C, 0-60 and 50-70 in gear accels etc but the footage doesn’t really do the conversion justice.
Traction in the wet – Normal driving is fine. The DSC cuts in when required. When driving enthusiastically the DSC can get a bit overwhelmed and give up but to be honest if you’re driving that hard in the wet then you would expect the back end to be sliding and probably have the DSC switched off. Wet roundabouts with a boot full of throttle and the DSC ‘sometimes’ decides that you’re on your own!
One thing that is a little annoying is if you hit the rev limiter, it puts the MIL on. Neil said he left that in the software for warranty reasons.
Obviously the car has more go than before but the problem with more power is that you get greedy and want even more. I thought about putting in a 2.5l engine and putting the S/C on to that but I've been advised that the Cosworth S/C is probably not up to the job due to the small heat exchanger.
My next thought was to put on a smaller pulley to give a little more boost. Neil has said he would be prepared to map for this but on my own head be it if the engine went pop!
The BBR conversion is on the conservative side of boost but this appears to make it reliable. You can't blame them for that after the maligning the engine got from the initial Cosworth installs.
In summary, I’m pleased I’ve had the conversion, it leaves a limited amount of scope for further tuning but
it looks like it’s intended to be there and it’s been trouble free.
There are other conversions out there for the mk3/3.5 but I think they are all U.S. based. BBR are now selling D.I.Y fit kits that makes it a little cheaper.
I know of another BBR/Cosworth owner on other Mazda forums called Bigkev. He had his car done before mine and has done more miles. I’m sure he would share his views/experiences.
Any other questions let me know.
Doggydog.
Neil at BBR was great with my endless questions before getting the conversion done, it is a lot of money but I haven't had the problems previous Cosworth converted cars have had. Neil has done quite a few conversions now and I've yet to hear of a problem car.
I've measured the fuel consumption over 2000 miles and have averaged 31mpg. Highest figure is 34mpg lowest is 27mpg. My drive to work is A and B roads all twisty single carriageway.
I’ve found that you need a couple more revs to pull away but it’s something you get used to. Neil says to turn the ignition on, wait 2-3 seconds for the BBR ecu to ‘shake hands’ with the Mazda ecu. In reality I forget to do this most of the time and its fine.
On turning the key to start it takes a split second longer to fire. S/C whine is not intrusive, I don’t really hear it unless doing a hard accel. On the mk3.5 the noise tube in to the cabin is removed, but that doesn’t bother me.
Driving the car is fantastic. I usually get bored with cars and change them after about 6-8 months. I‘ve had this one over two years now and it always brings a smile. Apart from the things highlighted above it behaves exactly the same as a standard car until you accelerate. It pulls hard and makes overtaking easy. With the standard car revving the up to about 6.5k seems to take ages with the S/C the needle flips round. I took some video (iphone) before and after S/C, 0-60 and 50-70 in gear accels etc but the footage doesn’t really do the conversion justice.
Traction in the wet – Normal driving is fine. The DSC cuts in when required. When driving enthusiastically the DSC can get a bit overwhelmed and give up but to be honest if you’re driving that hard in the wet then you would expect the back end to be sliding and probably have the DSC switched off. Wet roundabouts with a boot full of throttle and the DSC ‘sometimes’ decides that you’re on your own!
One thing that is a little annoying is if you hit the rev limiter, it puts the MIL on. Neil said he left that in the software for warranty reasons.
Obviously the car has more go than before but the problem with more power is that you get greedy and want even more. I thought about putting in a 2.5l engine and putting the S/C on to that but I've been advised that the Cosworth S/C is probably not up to the job due to the small heat exchanger.
My next thought was to put on a smaller pulley to give a little more boost. Neil has said he would be prepared to map for this but on my own head be it if the engine went pop!
The BBR conversion is on the conservative side of boost but this appears to make it reliable. You can't blame them for that after the maligning the engine got from the initial Cosworth installs.
In summary, I’m pleased I’ve had the conversion, it leaves a limited amount of scope for further tuning but
it looks like it’s intended to be there and it’s been trouble free.
There are other conversions out there for the mk3/3.5 but I think they are all U.S. based. BBR are now selling D.I.Y fit kits that makes it a little cheaper.
I know of another BBR/Cosworth owner on other Mazda forums called Bigkev. He had his car done before mine and has done more miles. I’m sure he would share his views/experiences.
Any other questions let me know.
Doggydog.
When I had mine done it was 5k plus vat. Obviously the DIY kit is cheaper. If you were serious about having a conversion done it's worth having a chat with BBR about options. They did have a 'buy it back' offer at one time that returns your car to standard if you want to sell it.
You can import a Cosworth S/C from the states but you have to get different hoses for right hand drive cars and your still left with the engine management side of things. I weighed up the pro's and cons and went to BBR.
Regards doggydog.
You can import a Cosworth S/C from the states but you have to get different hoses for right hand drive cars and your still left with the engine management side of things. I weighed up the pro's and cons and went to BBR.
Regards doggydog.
doggydog33 said:
When I had mine done it was 5k plus vat. Obviously the DIY kit is cheaper. If you were serious about having a conversion done it's worth having a chat with BBR about options. They did have a 'buy it back' offer at one time that returns your car to standard if you want to sell it.
You can import a Cosworth S/C from the states but you have to get different hoses for right hand drive cars and your still left with the engine management side of things. I weighed up the pro's and cons and went to BBR.
Regards doggydog.
OK cheers You can import a Cosworth S/C from the states but you have to get different hoses for right hand drive cars and your still left with the engine management side of things. I weighed up the pro's and cons and went to BBR.
Regards doggydog.
There's a local (to me) meet on wednesday: http://www.phoenixfives.org.uk/forum/viewtopic.php...
Yes we are in the process of some tuning -
Cosworth Camshafts - from Goodwinracing
Racing Beat header (no cat)
Racing Beat mid pipe (no secondery cat)
KN fitler mounted in front bumper in front of rad's via custom piping
2 way racing dampers
Custom Remapped on rolling road not the generic crap
Loads more done to chassis etc
All in all pretty quick for an MX5, next mod is a duratec 2.3 running an efi ecu but thats for next season we already have the engine but its a big job
http://farm8.staticflickr.com/7139/7021820995_e3ae...
Cosworth Camshafts - from Goodwinracing
Racing Beat header (no cat)
Racing Beat mid pipe (no secondery cat)
KN fitler mounted in front bumper in front of rad's via custom piping
2 way racing dampers
Custom Remapped on rolling road not the generic crap
Loads more done to chassis etc
All in all pretty quick for an MX5, next mod is a duratec 2.3 running an efi ecu but thats for next season we already have the engine but its a big job
http://farm8.staticflickr.com/7139/7021820995_e3ae...
Edited by speedy7 on Sunday 1st April 22:58
ISTR that the Frontline LE50 that was recently reviewed on PH had an MX5 2.0 engine and made 215bhp N/A. Does anyone know what they did to achieve that? Given that the car was £50k, there's plenty of room for the cost of doing that to be huge, but it just made me wonder what a 215bhp Mk3.5 would be like 
Prawo Jazdy said:
but it just made me wonder what a 215bhp Mk3.5 would be like
Not as quick as 235 bhp?http://www.bbrgti.com/product_details.php?id=11653...
Prawo Jazdy said:
ISTR that the Frontline LE50 that was recently reviewed on PH had an MX5 2.0 engine and made 215bhp N/A. Does anyone know what they did to achieve that? Given that the car was £50k, there's plenty of room for the cost of doing that to be huge, but it just made me wonder what a 215bhp Mk3.5 would be like
Thats on throttle bodies so the crap Mazda ECU has gone. You could easy get with throttle bodies and internal mods 240bhp but the bulk head on the MX5 restricts the use of some throttle bodies.Gassing Station | Mazda MX5/Roadster/Miata | Top of Page | What's New | My Stuff