How Many Miles on Your Supercharged RV8

[ChimpOnGas]

As the title, just idle interest to see what sort of trouble free milage people have racked up so far on their supercharged RV8s.

Is your Rotrex blown Chimaera an occasional toy or are you using it more extensively?

[Richard 858]

I've only covered around 2,500 miles in my 450 since fitting C38 & intercooler but with the exception of a faulty AFM have had no trouble at all.

[Hoofa]

No problems with the rotrex but everything else around it has been modified, best thing on the kit is the bracket, that's it ! You can buy the rotrex straight from TTS and engineer everything else, i had to fit a larger intercooler for intake temps and still went with water/ meths injection with what was seen on the dyno. Also a full 8 rib conversion has sorted belt slip and squeak out but then I am running the biggest charger. I think Phil ringwood that does the megasquirt stuff was making an alternative bracket.

Edited by Hoofa on Friday 26th December 09:37

[KateV8]

Think I'd best dodge answering this one!

[Richard 858]

KateV8 said:

Think I'd best dodge answering this one!

Come on Mark, come clean !

[ChimpOnGas]

Hoofa said:

No problems with the rotrex but everything else around it has been modified, best thing on the kit is the bracket, that's it ! You can buy the rotrex straight from TTS and engineer everything else, i had to fit a larger intercooler for intake temps and still went with water/ meths injection with what was seen on the dyno. Also a full 8 rib conversion has sorted belt slip and squeak out but then I am running the biggest charger. I think Phil ringwood that does the megasquirt stuff was making an alternative bracket.

Edited by Hoofa on Friday 26th December 09:37

Thanks, sounds like I'd be better off building a kit of parts myself then, the bracket being the only challenge, worth a chat with Phil Ringwood by the sound of it.

What Im really hoping for here is evidence of the Rotrex C38 longevity, Rotex themselves quote 62k miles but I'm hearing stories elsewhere of failures between 5-20k miles.

I was looking to see if anyone has actually achieved a meaningful amount of life from their Rotrex blower, its not a cheap unit compared with an OEM turbo that offers proven reliability so Id be keen to collect some positive information on life expectancy before I pull the trigger on a Rotrex compressor.

I know they've been around a while, but I'm not aware of any mainstream manufacturer choosing to use it (Aerial & Koenesegg are hardly mainstream). Perhaps that's because Rotrex aren't targeting the OEM market, or perhaps the are just too small to supply enough units, or is it because their blower still can't match a turbo for reliability & longevity?

If someone came on here with their own high mileage Rotrex story & a few links to others that have got a reasonable life from this compressor I'd feel a lot more reassured.

As it stands from what I can tell the Rotrex is still a bit of a reliability unknown with a one year guarantee and a statement from Rotrex that the unit can not be rebuilt.

I'd want a bit more backup from them than that given how expensive their product is.

Has anyone out there done meaningful mileage on a Rotrex with rock solid reliability?

If so Id love to hear about it.

[KateV8]

My engine barely survived the dyno run so not many miles there! However as I've stated on here previously it was nothing to do with either the blower or the installers, it was just the straw that broke the camels' back of a very poor engine build only 8000 miles before supercharging. Onwards and upwards though, Dom and Jay (not the original builders) have put everything right and Kate will be back home, supercharged and healthy, straight after Christmas :-)

[nickb134]

Hi COG Mr supercharged has been running his for a while, might be worth a PM. I think he is still on here. He's a top bloke very knowledgeable and helpful.

[ChimpOnGas]

Engine issues aside which is a subject with a million variables, I'd like to know if the Rotrex C38 compressor itself is robust or a reliability unknown.

To that end I'd like to hear from anyone that's had say over 40k miles out of one with rock solid reliability.

Do they stand the test of time, are they robust, or are the stories I'm reading of shafts bending and snapping between 5-20k just exceptions?

Actually 40k is nothing, I'd want a lot more life out of a Rotrex than that for the money they ask for the unit.

I don't think its an unreasonable question to ask, but I've Googled it back to front and I'm struggling to find one big mileage story let alone the raft of them Id hoped for.

All I'm finding is shaft failures at 5-20k and weak backup from Rotrex including the simple statement that their compressors can not be rebuilt so a new expensive unit is the disappointed customer's only option.

Anyone care to reveal another side to the story with evidence to show their costly compressors do actually offer a decent life?

Edited by ChimpOnGas on Friday 26th December 22:14

[sgrimshaw]

Where are you getting your information regarding the lifespan of the Rotrex blowers?

According to Rotrex expected life span is "hundreds of thousands kilometres"

http://www.rotrex.com/Home/Supercharger_Experience...

[ChimpOnGas]

Rotrex claim their compressors should last 100k kilometers which is 62k miles, but they only guarantee them for a year.

Their compressors are not rebuildable according to Rotrex themselves which is a bit pants when you consider the cost of the things, the link you posted is from a Rotrex dealer miss quoting Rotrex's own 100k kilometer statement.

All irrelevant really, I'm not interested in what Rotrex say, I want to hear from unbiased owners that have genuinely extensively used one of their compressors.

What I seek is backed up real world evidence that these compressors last the course, so who out there has actually put decent miles on theirs without issues?

I keep asking but the silence is deafening!

I really like the theory behing the Rotrex centrifugal supercharger and I'm certainly not looking for failures (quite the opposite actually), I'm really just seeking some reassurances the units offer a meaningful service life without issues before I commit my own hard earned cash on one.

Anyone?

[Pupp]

No first hand experience to call on to help with your query but have also seen some stuff over the years hinting at a degree of fragility. That said, I'm sure I remember reading something about HKS adopting and using the units in their tuning packages on the strength of their durability after a design revision. Maybe pick the phone up and give Richard Albans at TTS a call to discuss your concerns - he'll have seen big mileage ones if anyone has.
How much annual mileage do you expect to do after installing? Won't fuel cost be a barrier to stacking the miles up? There's no getting away from the fact the extra air going trough the motor will need extra fuel in direct proportion and if the motor is running, the charger is pumping... (unlike a turbo, which will cruise off boost)

[phazed]

What about Fatboychim?

He's had his self fitted and running for several years and is a TD fan to boot!

[Hoofa]

Tbh I think your asking in the wrong place, look at tts I think they do quite a bit for Hondas to add the rotrex. Might be worth a post in there, I don't know of any that are high mileage daily drive s/c tvrs. I did have a vortec supercharger on a golf , ran well for two years then a bearing went. Just like rotrex no chance of a repair which is absolute pants by the manufacter. This meant a complete new unit and as you can imagine it wasn't cheap, also consider that I don't think rotrex units are big enough for the amount of boost they produce, All the yanks on the blown Chevys use anything but rotrex.

Edited by Hoofa on Saturday 27th December 09:25

[Sardonicus]

Slightly off topic not sure why no ones never gone down this route http://www.procharger.com/

[rigga]

Supercharging or even Turbo charging a tvr has not been a long term feature as yet,only over the last couple of years has it been an option, so I don't think you're going to get any replies that will suit you, in short I doubt anyone with a conversion has covered any real substantial mileage.

[Bluebottle]

The rotrex and s/c power's kit has been the only reliable part of my build, it's survived 4 engine rebuilds, at least 6 rolling road sessions and somewhere between 18-22k miles.
Oh and for robustness, the 4th engine rebuild was because the car sat for 6/7 months at tvr specialist garage until they agreed to honour their warantee, in that time their resident mice ate through the k& n filters and deposited a load of bedding and Gravel in it. When the garage started her up it all got sucket through the rotrex....fked the engine good and propper...the rotrex however suffured a few minor abrasions to the impeller blades but was passed as still good. It's probably done 6 k since.

Edited by Bluebottle on Saturday 27th December 11:38

[ChimpOnGas]

Pupp said:

No first hand experience to call on to help with your query but have also seen some stuff over the years hinting at a degree of fragility. That said, I'm sure I remember reading something about HKS adopting and using the units in their tuning packages on the strength of their durability after a design revision. Maybe pick the phone up and give Richard Albans at TTS a call to discuss your concerns - he'll have seen big mileage ones if anyone has.
How much annual mileage do you expect to do after installing? Won't fuel cost be a barrier to stacking the miles up? There's no getting away from the fact the extra air going trough the motor will need extra fuel in direct proportion and if the motor is running, the charger is pumping... (unlike a turbo, which will cruise off boost)

Thanks Gary, all good points.

Agree more air needs more fuel which equates to a drop in economy, but at the same given cruise speed theirs an argument going forced induction may even have a positive impact on economy as effectively your increasing the volumetric efficiency of the engine.

If you want to improve economy on a naturally aspirated engine one of the first things you'd do is increase the compression ratio and in a way that's what your doing when you go forced induction, now factor in the additional torque you're going to be making with a blower, if you gear up the final drive you'll be able to hold the same give road speed using a smaller throttle opening and less revs.

All this adds up to better economy not worse if you compare the same car NA vs FI at the same cruising road speed, of course if you start enjoying all that extra power your inevitably going to suck more fuel but I'm not so bothered about this as even 17mpg on LPG is the petrol cost equivalent of 30mpg on petrol.

However that's not really what we here to discuss on this post, to my mind turbos are cheaper, make more power and are ultimately more efficient than any engine driven compressor can hope to be, but more important to me is their reliability is completely proven.

The Rotrex centrifugal supercharger has the advantage of very linear power delivery but if it's only going to last 20k miles I'll only be getting three years out of one before it needs replacement, to my mind thats not really what I'd call good value when a C38-71 costs the best part of £2,000.

I know the Rotrex compressor is used extensively on Hondas, MX5s, BMW ect but I can't find any stories of high milage units on these forums, has anyone seen such a post?

Edited by ChimpOnGas on Saturday 27th December 10:59

[Chuffmeister]

Sardonicus said:

Slightly off topic not sure why no ones never gone down this route http://www.procharger.com/

UK distributor here. TVR connection too.

http://www.rndengineering.co.uk

[ChimpOnGas]

Chuffmeister said:

Sardonicus said:

Slightly off topic not sure why no ones never gone down this route http://www.procharger.com/

UK distributor here. TVR connection too.

http://www.rndengineering.co.uk

ProCharger yes.. RND.. Nooooo!!!

The guy behind it is no engineer, more of a salesman who consistently fails to deliver on his promises.

Avoid!!!