MR2
|
| posted on 17/2/08 at 10:51 AM |
|
|
mid engined R2 awd bec
morning, new here but watched from the sideline for a while i have a bec with twin '99 R1 engines in the back. Two 3.62 lsd diffs (future
conv. to 3.14) front one usd. Curently constructing the last bits of prop and driveshafts parts. Iv been reading/hearing some scary stories about
needing loads of electronics to get it drivable. Spoke to zcars, tiger sc, motec and a man who build a awd twin busa seven. Geting different
story's. what i make of it is that i need some kind of TC system on the front wheels. Chalenge is that motec is very expensive and only did FI
engines(ultima busa and twin tigers) also should i fit the the tulips suplied with the fluke bafle kit? Could only find newer R1 examples on the
forum. Gr MR2
|
|
|
|
|
hobbsy
|
| posted on 17/2/08 at 11:52 AM |
|
|
Sounds very interesting, guess if you've got carbed motors you need a TC system that can cut the power using ignition cut rather than injection
cut. I don't know if there are many that do it this way. The Racelogic system I fitted to my 200SX cut the power by reducing the fuel enough
to cause a misfire (from mild on one cylinder to a lot more severe cut). Guess you could do similar with the ignition cut but not sure if it will be
as much control in the severity of the cut (i.e. all or nothing) but guess you can make it miss on one cylinder or more.
Are you going to run the standard Yamaha ECU's for ignition etc? Not sure if Megajolt or VEMS or similar built up in an ignition only form
could do TC for you (with the relevant optional extras bolted on)?
You also are going to need to fit aftermarket ABS sensors or similar to get the wheel speeds - but I'd imagine you already know this!
Re: the tulip I haven't bothered with one on my 03 R1 - Chris Gamlin on here has some racing logs around several tracks that show his oil
pressure is fine without one.
The All Bikes one already fitted to my car when I bought it was breaking up (as was the main plate itself - I did post photos a year or so ago).
|
|
|
MR2
|
| posted on 17/2/08 at 12:50 PM |
|
|
got cossie hubs on the rear incl abs rings. Both engines got electronic speedo signals. Cutting fuel sounds dangerous AF ratio wise. 200sx got 4
coils, R1 has 2. Had an awd idea with a ca18det and mt75 4x4 turned around, but decided it would be to heavy and to much torque. Im using standard
exup system with standard ignition system. Iv got the cnc baffle plate, looks pretty solid. Is it the same setup as 03? Why would they still suply the
tulip? Keep the (locost) ideas coming!
|
|
|
chunkytfg
|
| posted on 17/2/08 at 01:24 PM |
|
|
There's a company called Dynapro who are or have developed a system called a interceptor that works much like a power commander although without
the cheap ass maplins electronics.
They do a version of it that has supposedly got the ability to have traction control. Obvioulsy this is designed primarily for bikes but it might be
a useful contact for you.
www.dynapro.co.uk
Email Mark and see if he can help
|
|
|
chunkytfg
|
| posted on 17/2/08 at 01:24 PM |
|
|
There's a company called Dynapro who are or have developed a system called a interceptor that works much like a power commander although without
the cheap ass maplins electronics.
They do a version of it that has supposedly got the ability to have traction control. Obvioulsy this is designed primarily for bikes but it might be
a useful contact for you.
www.dynapro.co.uk
Email Mark and see if he can help
|
|
|
RazMan
|
| posted on 17/2/08 at 02:26 PM |
|
|
Russbost uses two engines in a similar setup and I recall that he didn't need any sophisticated engine management to make it driveable. He
simply runs them in tandem, one to each rear wheel and then syncronises the throttles on a balance bar of some kind.
He even mentioned that he has driven home on one engine more than once 
Not sure if that helps or not 
[Edited on 17-2-08 by RazMan]
Cheers,
Raz
When thinking outside the box doesn't work any more, it's time to build a new box
|
|
|
hobbsy
|
| posted on 17/2/08 at 02:59 PM |
|
|
Raz - I think its the 4WD that might cause the problems, i.e. maybe too much drive to the front wheels (I assume its one engine to the front wheels
and another to the rear) causing mega understeer or something?
MR2 - when I first heard about the fuel cut side I had horrible thoughts about things leaning out at high engine speeds etc and causing damage.
However it cuts that much fuel that it no longer fires so its not like its running lean. In any case that system won't help you if you're
carbed!
|
|
|
RazMan
|
| posted on 17/2/08 at 03:11 PM |
|
|
Ah, I see what you mean now!
How about something on the lines of an ABS sensor running to an ignition cut to maintain traction at both ends?
I love the idea of AWD but would probably go for a more conventional approach (and a big V8 )
Cheers,
Raz
When thinking outside the box doesn't work any more, it's time to build a new box
|
|
|
MR2
|
| posted on 17/2/08 at 03:13 PM |
|
|
exactly, one driving front, one driving rear.was the best option getting over 500hp/ton and traction. Was pasenger in a busaturbo 7, and it was faster
down the 1/4 mile with pasanger. Look into bike tc, thanks
|
|
|
MR2
|
| posted on 17/2/08 at 03:21 PM |
|
|
more conventional is a midengined V8 on a ford mt75 gearbox that sits in the driverscompartment like a lambo. 2 sierra diffs, front one usd and voila,
easy awd V8. just need a wide kit to acomodate the armrest
|
|
|
froggy
|
| posted on 17/2/08 at 04:29 PM |
|
|
i thought that until i realised that the front prop turns the wrong way so ive had to use a 6.5 sierra front diff instaed of the pair of 3.14,s i had
|
|
|
MR2
|
| posted on 17/2/08 at 06:21 PM |
|
|
sure you can use two 7" diff, just turn the front one upside down. Block the old breather and make a new breather pipe and filler bolt. You can
also make a conversion plate for the diff cover to flip it, some bolts even fit when turned usd. If it werent for the 3.14 ratio id use subaru 3.7
diffs, much lighter even though the are iron
|
|
|
froggy
|
| posted on 17/2/08 at 07:07 PM |
|
|
not with an mt75 box you cant dont think there is an easy answer for you ,with no physical link between the two axles its not going to be cheap
either
|
|
|
MR2
|
| posted on 18/2/08 at 07:32 AM |
|
|
i'm not using a mt75 gearbox.
i'm using 2 bike engines and two sierra diffs with no physical link between the two
hence the need for traction control on the front engine
you sugested to use a v8 and liked the awd idea
I just tried to explain how i first wanted to create a "easy" awd system in a midengined car. but i didnt want a heavy v8, more
something like a turbocharged alu vtec engine (turned clockwise)
suggestion is mating an V8 (or any engine) to a mt75 4x4 gearbox
the the engine is pointing to the rear and the gearbox is pointing to the front protruding the driverspace
(as a big armrest mid console)
jou just shift a bit weird becouse the gearpatron is mirrorred
the rear of the gearbox (now front) is driving the front wheels with a turned upside down sierra diff
the 4x4 selecter piece of the gearbox that now runs to the back is driving the rear wheels with a normal sierra diff
this diff is placed on the side/rear of the engine used
if you place the engine as far forward as you can, the rear diff can even be placed behind the engine
gr MR2
|
|
|
turbodisplay
|
| posted on 21/2/08 at 08:16 AM |
|
|
When are you looking to have it on the road?
One point against the mt75 4x4 gearbox is that 70% of the power goes to the rear (front in this application).
I gues you would idealy want to split the power to have more power to the rear in any case. I.e. have the throttles asymetrical biased to the rear.
Darren
[Edited on 21/2/08 by turbodisplay]
|
NOTE:This user is registered as a LocostBuilders trader and may offer commercial services to other users
|
MR2
|
| posted on 23/3/08 at 09:15 AM |
|
|
twin engined AWD BEC
looking to get it on the road this year. weight is about 600kg when finished. Got a bet with a freind that hase a fury with pinto engine, got to be
lighter than him. his car is 595kg. I filling the tires with helium
its about 75% finished now but the details and other projects make sure it takes longer dan i want
the torque split in the mt75 4x4 is indeed a problem, alternativ is to use the BMW ix transferbox, ( or porsche 4x4) it can be fitted behind every
(short)gearbox. I believe it lso has a visco in the centre diff.
Can anybody confirm that the TIGER AWD cars used electronics etc. to control them?? in the Utube movies the front spins like crazy when
accelarating.
also the guy I spoke to with a twin busa engined seven, (I think build for a disabled man in a race series) didn't use electronics but needed
two hand on the steering when cornering and shifting
also affread that TC on the front creates some very weird steering reactions.
|
|
|
