If I were to do a BEC next (and I am considering it....) it would definately have a turbo attached to it, as the one thing that
a BEC could do with more of is torque. (IMHO, of course) Tom
I'm up against a wall. What are people's opinions here?
I was thinking of going the R1-Turbo route with Programmable ECU, but i was given some advice against it. Mainly due to drivability.
Looking at the money i was going to spend on the turbo project, it works out that i could buy myself a Hayabusa engine, run it on the stock ECU with a
PC3, and dry sump it for good measure.
I won't have the same power, but it's output would be smoother. Engine has greater potential for modding too.
what does the BEC community think?
An engine with more torque and a wider spread of torque will be more drivable
So if its drivability you are after go for a well specced turbo engine. It will have more torque!
Turbo!
I wasn't convinced by the idea of people fitting turbos to bike engines. I mean they rev up quickly, have loads of power, sound brilliant
already.
I have a ZZR1100 engine in mine, which is really good, and I thought quite quick.
Then on Sunday Jambojeef took me out for a spin in his CBR1000 turbo'd locost. Now I see why people do it. It's just another level of
madness on top of a BEC!
No doubt Geoff will be along soon to tell you about the complexity of the install, the cost, the added time to the build, the teething problems
etc.
But once he gets the clutch slip sorted, that will be a very quick car indeed.
Mike
Ooh - turbo! Definately! Just finished a Zetec Turbo install, which is brilliant. Loving the torque at the moment, and I've still yet to turn the
boost up past 5psi. If I were to do a BEC next (and I am considering it....) it would definately have a turbo attached to it, as the one thing that
a BEC could do with more of is torque. (IMHO, of course)
Tom
djtom - car engines emit stronger exhaust pulses than a bike engine. So therefore, yes the Zetec will be great. Bike engines emit weaker pulses at the lower rev ranges, so the turbo will take longer to spool up. This is what worries me. Too much lag, then a lot of power surging in.
You are right about the exhaust pulses but it just means you have to be careful when you select a turbo.
TD04HL-16T-6? for the R1 engine.
A progressive boost controller would stop the power banging in too much and make it more driveable. You can also have different settings for wet &
dry roads if you like ........ which is nice 
yeah, the Haltech ECU can take care of all that. I can map boost against rpm, and gears.
Question to those who have turbo'd their BEC. After lowering the compression on the engine, has throttle response deteriorated off-boost?
Don't get me started - too late you just did.
A well designed turbo installation will improve any engine way beyond it's cost - and stories about driveability (ie turbo lag) are garnered from
people who have owned or driven badly specced turbo engines.
Go for a turbo but get a real expert to spec it and don't get over ambiitous about the power you want.
no such thing as a real expert on Turbo'd bike engines in my part of the world. So i need to get that help off the internet.
that's why i am posting here.
Well its not that complicated and it is worth it - I wouldnt have said that a week or two ago when I blew up my last engine though!
I went for the turbo since I really wanted a busa engine but couldnt afford it and wanted to do something a bit different. The final set-up (which
works) couldnt be simpler but having said that, so far ive been through an engine, about 7 or 8 different incarnations of the oil cooler system
(buying custom braided hoses every time - what a mistake), about 3 different versions of the turbo oil drain, 2 different intake systems etc etc since
I didnt really know what I was doing and there was only really Garage19 (Doug) to get in touch with.
Now its done, its fast and a hoot with all the whooshing and funny noises (some of which come from the car!) and stuff to make me think it was worth
it, but everyone says that when theyve got their car on the road so I sometimes wonder whether it was worth it - particularly since nows the time
where I iron out all the bugs!
You can get power cheap though - CBR1000 engines are very cheap and although heavy, make an interesting choice for a turbo - maybe not the best but
being fairly mild in tune, built very heavily and with a comparatively low compression ration as standard they are a good starting point.
My final system pretty much breaks down like this cost wise:
CBR1000f engine - £100
Garrett t25 Turbo - £50
Bigger oil cooler - £75 (probly do this anyway)
Intercooler (scorpio turbo diesel!) - £10
Malpassi fuel regulator - £50 iirc
Plenum custom made (badly) - £70
Custom pipework (induction side) - £100
Exhaust (reworked can and downpipe custom stuff) - £200
Bits and bobs - £50
So the total turbo system maybe cost me about £600 ish in current form but ive spent loads and loads on all the various stages up to now and god knows
what reliability issues there will be to come!
I reckon if its all out crushing power you want with awesome drivability and reliability you aint gonna get it with a home-built turbo.
But if you want a hoot with lots of power cheaply and are prepared to take the inevitable reliability issues on the chin and learn a lot about turbos
and stuff int he process do it!
Let us know how you get on!
Geoff
Is the CBR engine on carbs?
It is indeed.
All standard, springs and needles and jets unchanged.
Amazed it works at all actually!
beleive it or not i find EFI much much simpler and more logical.
ECU calculates how much air mass comes in. ECU looks up how much fuel it needs, then spray it. ECU fires the the plug at the exact precise moment.
Lambda sensor reads the resultant exhast, and tells ECU that it just made an utter crap of it. ECU reads Air mass again, sprays fuel, this time
taking note of what lambda said. Plug fires, then lambda criticises the ECU again.
It's a bit like a government running a democracy lol.
Efi is preferable without doubt if you're after driveability, all out peak power not making much difference of course.
A winter mod for me was always going to be 'squirting it - not this winter though, its only just got on the road!
Does this T3-50 make sense? the calculations are for a 04' R1 engine, with 0.8Bar boost.
10:1 compresion, Intercooler, and water Injection.
Rescued attachment Boost map.JPG
Personally, I reckon you’re better off going for a naturally aspirated BEC. Don’t get me wrong, nothing appeals to me more than the performance of a
turbo or supercharged BEC but in reality I think you’re always going to have reliability issues with a turbocharged engine in a BEC and will
ultimately end up somewhat disappointed.
Let’s face it, you’re already pushing the limits of the components on a standard motorbike engine installed in a BEC and therefore ultimately reducing
it’s lifespan. They simply aren’t designed to be powering a 500kg vehicle + driver + passenger for any length of time. Bike engines are built to high
specifications, using tight tolerances and will cope quite admirably for a long time without modification in a BEC but up-rating components within the
engine to cope with a turbo simply transfers stress to other components within the engine, which aren’t designed to take those forces and ultimately
something will break.
If you consider the inevitable repair/downtime a good price to pay for the associated increase in performance, then go for it but my advice in the
majority of cases would be to go for the largest capacity/most powerful naturally aspirated bike engine you can afford, optimise it’s potential and
then enjoy driving it……….
Phil
I love forced induction. Forced induction on a BEC suggests one thing only to me which is that it will give you the torque that you are missing using
a bike engine as opposed to a car engine.
My advice would be don't get too ambitious with the boost too quickly. Start by getting it installed and set up at 5-7 psi and then work from
there. This will be a very locost approach and you will not need to reduce the CR. You will be amazed at what a transformation even this relatively
low boost will provide. At this level the engine, even with a relatively high compression, will be relatively unstressed. When happy with the basic
function, get it on a rolling road and check that it isn't leaning out at any point in the rev range. Then simply enjoy the torque. It will get
to a stage where you will want even more power and you can then tweak accordingly. If using carbs as opoosed to injection, I would suggest that you
use a high pressure fuel injection pump with a rising rate fuel pressure valve which controls fuel flow based on boost as it takes a feed from your
intake. You will need to fit a return fuel line but this set-up works very well on my turbo pinto fury.
One other must include item for the shopping list has to be a 'turbosport' type valve. This holds all the boost which you dial in away from
the actuator prior to your selected boost being reached. This eliminates all 'wastegate creep' and ensures that the turbo spools quickly.
I would also suggest that you go for a relatively small turbo so that you don't experience the lag which you are worried about!
In summary get it turbo charged and enjoy!
quote:
Originally posted by clutch_kick
Does this T3-50 make sense? the calculations are for a 04' R1 engine, with 0.8Bar boost.
10:1 compresion, Intercooler, and water Injection.
more boost sir MB CUSTOMS LOL
quote:
most modern bike engines have very high volumetric efficiency to start of with so you have to size the turbo to match this when i worked out the numbers properly using ricardo wave for the r1 04-06 i came up with the gt28rs as the most suitable size which is a fairly big turbo but it would be working far more efficiently than a t3 sized turbo and would spool up fairly quickly being a roller bearing setup.
Pick a small'ish Turbo and run a modest amount of boost...
Accept that you will have to spend time/money developing the car so all the inter-related systems work with the extra air... The clutch, oil/liquid
cooling, fuelling, compression ratio, the gearbox, charge cooling, engine bay heat etc etc etc.
Having said that - My Turboblade runs 7-9psi with no discernible lag. In fact the 'rubber band' appears to be on my side as the 'here
it goes - screaming mad' point is much lower than on my old N/A blade car and gives a wider (rev) range that's usable, making it easier to
drive (rather than the other way around...), so from my particular point of view, well worth doing!
[Edited on 2/11/07 by mb893]
quote:
Originally posted by kb58
quote:
most modern bike engines have very high volumetric efficiency to start of with so you have to size the turbo to match this when i worked out the numbers properly using ricardo wave for the r1 04-06 i came up with the gt28rs as the most suitable size which is a fairly big turbo but it would be working far more efficiently than a t3 sized turbo and would spool up fairly quickly being a roller bearing setup.
The gt28rs is a good modest-sized turbo for a 2-2.5liter car engine. The bike engine is about half the displacement, but spins about twice as fast, so its mass flow is around the same. As said though, at lower rpm, lag can be a really big annoyance.
Nearly everyone will tell you to turbo because they aren't paying for it themselves, and don't have to fix it when it breaks. People who already have a turbo'd car want you to have one, too, because it helps them feel like they're right in their decision. Yeah I'm generalizing, but it's important to keep in mind people's true motivations when they encourage you to do something. Most people, if they're really being honest, will say that a turbo is, "Great fun, but..."
The answer is obvious - you have to drive a turbo'd BEC to make up your mind. The huge deciding factor is turbo lag. If you check out YouTube, you can find videos of kids who've put a huge turbo on their Honda, cranking them up to 600hp or so. The funny thing is watching them on a road racing circuit - the car's all but undrivable. For drag racing though, it's not so bad.
So the real issue is, what are you going to do with the car, and how will lag affect it. And finally, you're the one who ultimately has to pay for it and fix it if it breaks.
Edit: everyone keeps talking about torque as the reason to go turbo. The trouble is that this torque is delayed in application by lag - the rubber-band effect. A supercharger on the other hand gives zero lag and all the torque down low. Unfortunately on a bike, it revs way higher than a positive displacement supercharger can handle. And the centrifugal superchargers, well, IMO they have to worst of features of both.
[Edited on 11/2/07 by kb58]
Everything I've read about turboing a BEC states that lag is not a noticeable issue--even with the bigger turbos. Of course the turbo needs to be
well matched. I've been thinking about this a lot more lately, so interesting to see the turbo BEC comments.
--Chris
I've got plenty of experience with turboing, car engines, but they are kind of 'easier' to work with. The lower revs and stronger
exhaust pulses make life easier.
To me it seems that the TD04HL-16T-6 would be the most sensible turbo for a ~1000cc engine. At this point in time I do not think that it is worth the
money to spend big on a ball bearing turbo. Especiallay since i don't intend to run any sort of mad boost on it, yet.
I'm just undecided. Don't know if it would make sense to turbo the R1 engine for Hillclimbing, or stick in a busa engine.
I'm a bit biased towards the turbo route, but going N/A busa power seems a bit like cheating, no challenge.
I'd always be worried about the turbo changing the charateristics of the bike engine. I spoke to holshot and he seemed to suggest on a busa peak
power was made as low as 6 or 7k, with that power being held right up to the redline. For me that would feel odd to drive.
For that reason I would be more tempted by a supercharger conversion. The linear power deliverey would affectively keep the engine characterisitcs the
same, but just produce more torque and power. The only problem is I guess the cost of the Rotrex units.
I take it a low pressure turbo would work better with a bike engine? Or does the weak exhaust pulse actually mean the power can still be achived
higher up with a broad spead?
The trouble is that superchargers and turbos run over a range so a supercharger will probably be more of a challenge higher up the rev range to keep
boost and will tail off.... changing the charactreistics of the engine.
The trick with forced induction is to spec it to the application regardless of method used.
Personelly I prefer turbo's purelly as they don't rob the engine of some of the extra power produce..... I'd love to turbocharge my
injected R1 engine.
to many projects & ideas and not enough money & time.