Lpg Turbo 5k

[beerhead]

Hey,

 

I've started accumulating the bits and pieces for my turbo 5K.

 

The plan is to use my 5K block, bore it out 0.5 - 1.5mm. Use some 78 internal, 81 - 82 exteranl, cast steel sleeves in the bores. I scored 4 rb20det pistons with 80k on em for 20 bucks! So that should work nice with some brass inserts to connects the rods. The pistons are 3.2 mm shorter than a 5K unit so I'm gonna deck the block 1mm and shave the head 1mm too, and use a 1mm copper head gasket with a double O-ring. I'll reconfigure the head a bit too. It should be about 1.4 L and 7.5 - 7.8 : 1 compression ratio after that. I plan not to rev it too hard so I'm gonna stick with standard 5K rods, though I might have them and the crank cryoforged.

 

I'm gonna track down either a T25 or a T28BB turbo for the job, and make a custom manifold for it.

 

Becasue of the space confinements I'm going to try to convert a water to air intercooler into a cooler inlet manifold, cosworth has a similar setup in some of there rally cars. I think it will be a complete custom case for the guts of the unit, because to flow effectively it will have to be fed at both ends.

 

I'll be getting a 350CFM gas research carb and a convertor for the job of fueling it up. Down the track I might look at an ecu with methanol and water injection control.

 

Now I gotta get the 500 bucks for a Ke20 coupe :down:

[Tiger]

Sounds like you got your hands full there dude! :down:

[Super Jamie]

sounds interesting

 

i'd try and run a thinner quench area, deck the block an extra 2mm on your above plan, and port the head for less compression if you need it. you can only force about 0.5 bar into a K motor before they go bang fairly often, so don't be afraid to run a higher compression than in the 7s

 

the extra octane of lpg will give you a little more leverage too. the biggest i'd run on a 5K would be a T25. angela in SA had a race spec T28 on her turbo 5k and it was a laggy pig. she's currently having great success with a HKS2530

 

any treatment you have done to the crank and rods will be money well spent

 

keep us posted

[ROLLN'03]

Ill sell you my t25!

 

Sounds fun, can't wait to see pics!

[beerhead]

Ok,

 

How much are you chasing for the T25?

[mikeys toy[RL]]

lpg? as in propane?

[beerhead]

Well if your up north in QLD above gladstone you will have pure propane in your car :P 112 octane. Down south of this point you will get a butane propane mix that is about 104 octane. People winge about dry fuels, but when you see a well configured LPG car you can tell there is no problem with it. On the sunshine coast a mate of mine has worked on a VL with an RB30et in it with a 650 cfm gas research carby making 450 hp at the treads on 16 psi :D

 

Basically you turn your intake manifold into a refrigerator when you use LPG.

[mikeys toy[RL]]

ummmm....ya!

we used to run lpg in the tow trucks, we'd bump the timing up 30* (we had to, the only way they had any power)

the throttle body/carbs were always icing up

we had to replace exhaust valves every 10,000 mi

and I'm pretty sure you will have head cracking probs with the aluminum head

i'd rather stick to dinosaurs

[Super Jamie]

lpg works great on K motors. brad makovec from oldrollas had a supercharged 5k on lpg which he used for 18th mile drags

[beerhead]

I think ... hope, the extra heat compensation of 15psi of boost will even up any head temperature issues. I haven't heard of much problems with LPG if you get a specific cam profile for the job. Vehicles that are dual fuel tend to have bigger troubles, and be less econmical than a fixed LPG car. The other thing I was thinking about was a prime button attached to a 5L tank of premium in the boot. Squirt in 50mls of petrol into the intake manifold before you turn the key might help dry starts., and I haven't heard about a system like this before

 

Brad

[Super Jamie]

15psi? i doubt you'll manage that but good luck trying. a cryotuffed 5k is an expensive engine to kill, how about you just keep it in single figures?

[mikeys toy[RL]]

yeah, ours were dual fuel....wayy before i was an itch in my daddy's pants. they gave up around the time i was born

[beerhead]

It won't be a fixed boost car, it'll have an electic boost controller for 8 and 15 psi. Click the button fire show on demand past 8 grand :P

[beerhead]

I've been thinking ...

 

For the reliability of a turbo K motor, it'd be worth sticking in the single boost figures, as super jamie says, and I'd agree too, they aren't designed to be a forced motor. So, it probably isn't worth the cash to sleeve the motor, so would I be better off boring a 4K to 78mm ? I'm not sure what the maximum allowable bore of a 4K is, but loosing 1.5mm off each wall doesn't seem like too much to me, anyone?

[beerhead]

I have a 5K :D I want to keep that engine NA for my daily driver, and build a turbo weekend car. How much r u looking at to get your KE70 complianced with the 3sge in it? I've heard of some late model corona crossmembers that bolt into a Ke55 corolla that give you 2s engine mounts, apparently the gearbox crossmember bolts straight in too. I'm sure an engineer would like that. Does anyone know anywhere cheap to get engineering done, Brisbane area? I'm trying to do everything on the pov, I should be done with it and save up for a 3SGTE hey, stock a corolla would shred with that under the bonnet.