PopKat

[Redmohawk]

Picked up the Popup thats been floating between members here for a bit the other day Drag'd the old girl home Results so far. Strip down to the frame to have a look see at the damage, a bit of cocky shit welding to fix some rust to blast off before some paint.

Plastics are all there but looking very used, will repair them and make a set of moulds to copy the lot in Carbon fiber, Not really interested in loosing heaps of weight but I've got the carbon so why not.













Found a front rim off a gn250 this morning so Its going to have wire wheels !



Not sure what this one is off its a steel rim with a huge hub might squish it into the swing arm with a 4.5 inch rim wide 17 inch rim on it.

[fimpBIKES]

bigger engine on the cards?

[Redmohawk]

Buying a gsxr750L and a set of USD gsxr forks (care of Dylan ) , Got a turbo here looking for its mate for twins fimp . So not bigger but a little more push than stock .

[fimpBIKES]

fair enough, its about how you use it anyways yeah? (thats what i tell myself...)

[Redmohawk]

Will be on club reg so I'll use the crap out of it 90 days a year !

[oldskool]

Buying a gsxr750L and a set of USD gsxr forks (care of Dylan ) , Got a turbo here looking for its mate for twins fimp . So not bigger but a little more push than stock .

Three times the push!

[Redmohawk]

Ok folks plan is eather a pair of IHI RHB31 V21 spec turbos (little fuckers that came on daihasu and suzuki 3 cyl 660cc kei cars) or

A pair of IHI RHF4 turbos taking the VF25 spec front and rear housing (p12 rear housing, front housing is .36 A/R) and sticking it onto a VF27 spec body (the RHF4 VF25 is a primary turbo on early suburu liberty has oil bearings the IHI4 VF27 spec is a ball bearing centre same size as the VF25 but the scondary turbo) Fitting the VF25 front and rear housing to the VF27 gives me a ball bearing turbo with very small exaust housing to make it spool up very fast.

I'm having trouble finding a good compressor map for the RHF4 VF25 probably as its small and insignificant in the modified car field. The VF 27 is about as looked after in that regard as the VF25 I know it has a exaust housing p18 and the front is A/R .63


If I use the RHB31 I have one already and another could most likely be sorced resonably cheap , It maxes out at about 120 hp each and due to its very small size should spool very well in a pair on the 750. Prob the smarter option and being a oil bearing as it will be cooled by oil flow and not need the water conections (being an oil cooled bike n all) If I go with the RHF4 V27 I get ball bearings and potentally alot more airflow with something that shouldn't be "lagy" but it will need water cooling .

Some maps n shit for Pics






Im aiming for boost at below cruse speed with a smooth torque ramp not a masive rush all at once, and a mild boost of 6 to 8 psi max on the stock motor with good fuel and an intercooler.

[Redmohawk]

Another bonus is the smaller turbos will fit high on the front of the bike a whole lot easyer intakes facing out eather side exaust outlets in the middle running to twin pipes and cans. Being high will hopefully alow gravity feed of the drain back to sump.

[fimpBIKES]

hidden turbos? love those setups

[Redmohawk]

Na not hidden. High mounted around where the headers exit motor, Somewhere about here.



Turbos are tiny will rotate comressor housing to face up I think and run twin polished ali pipes over motor head at eather side to intake manifold parallel with fuel tank bottom. Might make up some air filters using 5 inch dia "big pod" type filters that go over the front of the turbos to block they're view from the side/front a little. And the oil cooler will go above them to box them in visually a little. Maybe a bit of polished stainless steel sheet bent into a shroud over the front of them ?

[Redmohawk]

Thinking I might delete the wastegate actuator in its current mounting position, run one larger unit for both turbos instead of two stock units. Mount it in towards the motor above the manfold behind the oil cooler with a lever arangment to work both wastegates in unison to get it out of view.

[slingy88]

Will be watching this one. Should be a real interesting set up.
What you gonna do for fueling? Blow through carbs or EFI?
Theres a real good set of Slabby 1100 carbs on the bay at the moment. These are the best for GSXR blow throughs but getting real hard to get.
CV's, all metal construction (including carb tops and slides!), 4 screws on carb tops and float bowls making keeping them sealed easy, and the float valves are the old brass seat and valve design so are cheap to replace if needed to handle the slight increase in fuel pressure from the pump arrangement.+ they have been proven easy to setup and robust enough for 30psi boost!

Anyway, i luv the pop's and one with a blown 750 is gonna be something else

[Redmohawk]

Thanks for the carb tip , it will be a blow through carb setup and I need a set !

[slingy88]

http://www.ebay.com.au/itm/Suzuki-Gs...4#ht_85wt_1170

Round necks make plenum building easier as well and only single fuel feed and single float bowl vent makes pressuring easier too.
I would buy these myself just to have for the future but i still need clutch, clutch master cylinder, carb rubbers, oil lines blah blah.................So, better be sensible and save me dosh.

[Redmohawk]

I'm in a much worse boat atm bloke , working for myself just scraping buy atm till things pickup its very hard to pick up extra cash to buy parts for bikes. Atm I've been turning "long term keepers" in the shed into cash to buy other bikes and bits "that I just have to get now" and the Kat was one of those "Just get it now and make it work" deals.

[slingy88]

I here yah, i'm always on the scrounge for budget options. Thing is, i have little money and little time so always weighing up the best comprimise of the both. Like, i picked up a used remote filter fitting for $10, then i need a sandwich plate to take the pipes off the motor to it. Now, i have enough alloy and the tools to just make it for free, but that would take alot of hours, better used in my mind to build the exhaust, or intercooler or something, so instead i have bought a chineese job ($14 including delivery!) but this will still need a little work to fit the 20mm X 1.0 thread on the motor and a cover plate to turn it from a sandwich plate into a dedicated "Oil take off" fitting, but still as good a comprimise of time and money as i can get i think.

Anyway, didnt mean to hi jack your thread. Just trying to say i suppose, that theres always a way to make these things work, even if it ends up being a bit of a comprimise.
Red, keep at it, and as long as you have the vision you will get there.

[Redmohawk]

lol my thread isn't hijacked , the thread is like my bikes . A working progress, Yeah time I'm short on cash the same ideas a plenty.

[latheboy]

When you make the headers put an AFR bung (M18x1.5) in each pipe out of the head, if you don't have the room put a 1/8" NPT female bung instead about 40mm from the start of the exhaust.
I used 4 EGT's and 1 AFR to tune my carbs and tuned each one independently, you will need an AFR bung as well after the turbo's.

Another thing that would be good (i'm about to do) is put a 1/8" bung in at the collector before each turbo for a pressure sensor.
Then you can measure the exhaust ratio and see if the headers are working well.

The great thing about turbo's is no matter how bad the headers are they will still work, maybe not the most efficient but will still work.

1 link pipe or 2 to the plenum, if 2 ... Make sure they are symmetrical to the centre line or you will have heaps of problems tuning.

I had 38mm carbs on my bike so i just used them, they are great.
I made new Al. tops for them because i could, the plastic ones are "meant" to be good for 15PSI.
The important things to do are the boost comps and sealing the carbs.
OSS had some good info but it's all gone, if i can find what i saved i'll send it to you.

Must have return fuel to the tank, fuel fliter MUST be after the pump.
Also a good idea to have a fuel block afte the reg, 1 in from the reg and 3 out. 2 outs to the carbs and 1 for a pressure guage.
I like to see fuel pressure and would rather see fuel pressure then a boost gauge.

It's different for me i guess cause i can map everything on the dyno but it's a good idea to have as much info as you can.

Get yourself an 1100 coil spring clutch, flywheel and all then mount the 1100 basket onto the 750 flywheel.
Get a MTC clutch spacer and machine it down to ??mm (I'll measure mine) so it all fits in and you will have to mod the cable actuator.

I'll think of more later.

[Fight_fan]

Cool project Red! Will be keeping an eye on this!

[slingy88]

Cant aggree more about the fuel pressure gauge. Its one of your most important bits of info when going blow through.

For anyone looking to go turbo, this is a real good read with lots of usable rule of thumb tips for designing a system.

http://www.unclebobsturbos.com/newbie.html