Evening everyone.
i have a MNR with 5jj carbed r1 motor, only really use the car for trackdays and the occasional Sunday outing,
wouldnt mind having a go at some sprints in the future possibly,
anyway, as much fun as the car is i just can't get past the lack of power it has.
last week at Brands Hatch i was really struggling to pull a gap on a Clio 182 down the straight, i found myself catching up to most other cars on the
corners but kept getting creamed down the straights and it got abit dull.
So i'm thinkin about an engine swap, i want to stay bike engine as i like the gearbox and the high revs,
so i was wondering what bike engine provides the biggest bang for your buck?
i was thinking something along the lines of a zzr1400 maybe?
anyone care to offer some advice ?
thanks
Stick a supercharger / turbo on the engine you've got?
Saves a lot of re-wiring / engine cradle alterations?
The clios are quite fast on track lots of power and low weight. Turbo the r1 or swap to a busa or zzr1400 if i was building again i would go honda s2000
is it possible to turbo/supercharge with carbs? that would definatly be an option,
It is better to turbocharge with carbs...
http://www.turbo-bike.net/
Have a read of this and then feel free to ask questions on here. (start a new thread if you go down this route)
You may end up with a few answers from people that just want to "take-part" but there are also a few people that know what they're
talking about...
[Edited on 16/6/11 by Steve Hignett]
^^
i have to disagree its far easier to supercharge with carbs as you just fit larger jets, if u turbo you can either jet it for on boost in which case
it will idle very rich or jet it for off boost in which case it will run lean at the top
tilly
quote:
Originally posted by tilly819
^^
i have to disagree its far easier to supercharge with carbs as you just fit larger jets, if u turbo you can either jet it for on boost in which case it will idle very rich or jet it for off boost in which case it will run lean at the top
tilly
ahh sorry i did indeed misunderstand you, though out of interest why do you say it is easier with carbs than injection, setting up a set of carbs for
turbo boost is a nightmare when with injection its just a case of a power commander and a new map admittedly more expensive but much easier IMO
tilly
As Steve says with carbs it quite easy to do, the link Steve has posted is where i got most of the info to do mine.
Turboed my 4xv about 3 years ago best thing i have ever done to the car apart from going bec in the first place
it made 257bhp on the dyno running just under 12psi
ah i see
very good link
tilly
What ratio diff are you running? That could make a big difference for a relatively low outlay.
Other things to consider would be a jet and needle set and a sausage filter if not already fitted (and a proper set up on a rolling road).
Turbo it, you know you want to
ah your the chap with the sr20 i was chatting to at Stonleleigh,
i'm tempted by the turbo option,
the diff is a 3.62 and the car has been dyno jetted, perhaps i am expecting too much from it?
Thats the one
I think you are expecting a little too much, what you need is a bit more torque to be able to push the brick shape of a 7 through the air.
With mine at 120mph you put your foot down and you just start going faster Not so much fun in the wet (gets a little scary)
Go on turbo it over the winter, that gives you the summer to get the bit for it together.
quote:
Originally posted by locoR1
As Steve says with carbs it quite easy to do, the link Steve has posted is where i got most of the info to do mine.
Turboed my 4xv about 3 years ago best thing i have ever done to the car apart from going bec in the first place
it made 257bhp on the dyno running just under 12psi
quote:
Originally posted by Steve Hignett
http://www.turbo-bike.net/
Have a read of this and then feel free to ask questions on here. (start a new thread if you go down this route)
You may end up with a few answers from people that just want to "take-part" but there are also a few people that know what they're talking about...
[Edited on 16/6/11 by Steve Hignett]
I was in same position as you, but i have a CBR900 N spec engine. In the end i went for ZZR1100 over some the the newer engines, purely because i
felt it was bomb proof. 2.8k for a low mileage Busa is way out of my budget, ZX12-r are great engines, but dont have the strongest of boxes, but
can be tuned very cheaply to 190bhp-200bhp. I was going to S/c the ZZr and as reliable as it is, even with forged internals i feel the box would
would not take the punishment. I was told by a bike engine builder, expect to strip and rebuild the bottom end every 3k , if you turbo it ! My
mates got a ZX14 in is locost and he loves it. he did say that on a track day a lad was running a locost with a R1 on a rotrex charger and after 3
FLYING laps, he had to come in & let the oil temp cool from 120oc !
at the very least your going to need Forged pistons+ rods + forged exhaust valves. My own preference would be aftermarket ECU , blowing through
Throttle bodies and it would be easier to setup and give better bhp over a carb setup.
Andy
did he have proper cooling mods on that car with rotrex charger as thats just silly and abit pointless,
we had a little trouble with the S2000 turbo getting hot but a larger oil cooler sorted the oil temps out perfectly,
i wouldnt be running much boost so with slightly lower compression and keeping it nice and rich on the afrs should keep it all cool enough to not melt
pistons i'd think.
i think i'm going to have a bash at it, 4xv and 5jj engines are cheap as chips to replace anyway.
quote:
Originally posted by gaz_gaz
ah your the chap with the sr20 i was chatting to at Stonleleigh,
i'm tempted by the turbo option,
the diff is a 3.62 and the car has been dyno jetted, perhaps i am expecting too much from it?
i'm probably wrong about this as i am with most things but that would give me a higher top speed and slower acceleration?
quote:
Originally posted by gaz_gaz
i'm probably wrong about this as i am with most things but that would give me a higher top speed and slower acceleration?
quote:
Originally posted by gaz_gaz
i'm probably wrong about this as i am with most things but that would give me a higher top speed and slower acceleration?
OP doesnt say if the problem on the straight was running out of revs at the end, or whether he simply didnt have enough acceleration/grunt between say
80 and 120mph.
If you were just to change the diff to suit the circuit, then you simply adjust it so that it approaches max revs on the fastest straight, which might
well require a 3.36. However, if the car isnt pulling well enough down the straight, the last thing he needs is a longer diff which would lower the
revs.
yep as Joel says.
i'm running out of straight before i run out of revs so would like abit more grunt for that reason,
maybe with more power i'll be running out of revs then i'll look at the diff but i'll need to wait and see.
[Edited on 17/6/11 by gaz_gaz]
its was a 4k kit, drive in , drive out
LOL would hope to get an oil cooler for that
why dont you go 42mm TB's , emerald / omex , freshen up the bottom end. . I'm sure you would see over 180bhp.
Do you actually know what the engine is producing? i.e have you been to a rolling road?
Its quite common that people have not optimised what they have, losing bhp and acceleration through poor intake, exhaust design and non optimal
jetting. Is there nice cold air going into the carbs?
A well setup 5jj should be putting out >160bhp (roughly 135 at the wheels) and with a 3.62 should be ideally geared for Brands. What was your top
speed on the straight - it should be >120mph. If not it would suggest you are down on what you should have.
Food for thought before you start spending cash on upgrades.
One simple upgrade is to lighten your car - do you know how much it weighs? MNRs are known for being a bit porky.
Personally, if all is well and you just want more grunt, I would put a ZX12 in there. Cheap and plenty of power and can be simply tweaked to give
more. Far more reliable solution than super/turbo charging.
Regards
Paul
quote:
Originally posted by hiflow
its was a 4k kit, drive in , drive out
LOL would hope to get an oil cooler for that
quote:
Originally posted by progers
Do you actually know what the engine is producing? i.e have you been to a rolling road?
Its quite common that people have not optimised what they have, losing bhp and acceleration through poor intake, exhaust design and non optimal jetting. Is there nice cold air going into the carbs?
A well setup 5jj should be putting out >160bhp (roughly 135 at the wheels) and with a 3.62 should be ideally geared for Brands. What was your top speed on the straight - it should be >120mph. If not it would suggest you are down on what you should have.
Food for thought before you start spending cash on upgrades.
One simple upgrade is to lighten your car - do you know how much it weighs? MNRs are known for being a bit porky.
Personally, if all is well and you just want more grunt, I would put a ZX12 in there. Cheap and plenty of power and can be simply tweaked to give more. Far more reliable solution than super/turbo charging.
Regards
Paul
i reckon i managed to loose 50kgs out of my locost when i binned a few bits. Both seats, the dash, the windscreen and the tunnel cover