Safe boost pressure?

[petew]

Ok, so some nice stuff there. I guess the issue with the crank is whether it's welded, forged and where it was forged or whatever. Hard to know without pulling it apart and having it tested.

[kobuggy]

Based on the fact that I don't know what cam, crank, or rods are in my motor, is there a general rule for the amount of torque or RPM that stock rods & crank will take? It's not a stock crank but I'm looking for worst case scenario. I've got my rev limit set at 6000 rpm with a 200 rpm soft limit, at the strip it feels like it still making power when I bump the limiter. How much higher can I safely raise the limit?

[rubenski]

I'd raise the limiter bit by bit. See how far you want to take it.

[Piledriver]

A stock crank (non-counterweighted) keep it under ~5K, a nasty crank flapping, case beating resonance occurs on a stock T1 crank ~5500 RPM. Counterweights on an ACVW crank add mass and eliminate the resonance.

VW achieved ~the same on the T4 and WBX cranks by making areas of the crankshaft much heavier.
The T4 also has all 3 "real" mains 55mm dia, which helps keep a stiff crank.

Any 78mm crank for a T1 almost certainly be counterweighted, if it was for the military it may be a SCAT or Oettinger or even Berg unit.

They seem to have used some very nice parts on those buggies.

[Wally]

There´s no ´safe´ boost pressure, there´s only a safe tune...

[kobuggy]

I agree, that is what I'm after. I got my second hand meth kit installed today.

[rubenski]

Thinking of a w/m install somewhere down the road too.

Got a build topic where we can take a look?

[Clonebug]

Thinking of a w/m install somewhere down the road too.

Got a build topic where we can take a look?

This is sort of what I used to build my setup....

http://www.turbomirage.com/water-alcoho ... -list.html

I also read a lot on this site...these guy have been pushing power through an airlcooled engine for a long time and seem to know their stuff.
Lot's of great reading if you dig deep enough...They are all about weight and packaging due to putting it on a Bike but it still is good info I think.

http://www.rbracing-rsr.com/waterinjection.html

For you it will still come down to packaging. It was an issue on my buggy too.

You can see the tank and pump on the right side of the pic hanging from the torsion bar.



If I was to do it over again I would buy the pump from "Devils Own" or someone and maybe the nozzles and then source everything else locally.
All the push-locs and hose can be bought at your local fitting supply store.
The Electric solenoid can be bought for about $11.00 on Ebay.



The Hobbs switch is about $40.00 at my local NAPA Store unless you are going to use an ECU to control WI.

On my buggy it stops the detonation from around 8-10 lbs all the way to 22 lbs so far.

You must make sure it works all the time and never runs out of mix. Bad things will happen when pushing that hard and there is no water......I have an EBC and with a flip of the switch can turn the boost down to the stock waste gate setting of 6 lbs. A good fail safe.
I also installed a low water level indicator light so I know when I am going to need to add the Water/Alcohol mix.

[andy198712]

Wonder if that low indicator would trigger your EBC?? One for Mario to work out lol

[Clonebug]

Yes you could have it trigger a relay but the problem is when the lower fluid levels make the light flash on for just a second or two. It's quite easy to just hit the switch on the dash and turn off the EBC. I have a second switch next to that to turn off the WI.

[Chip Birks]

I prefer taking myself out of the equation as much as possible. Let the ecu do the thinking and reacting.

[Clonebug]

I prefer taking myself out of the equation as much as possible. Let the ecu do the thinking and reacting.

I just never let the light come on......

[Chip Birks]

Thats good too. I still have yet to even use the system. Filled it with water Thursday, and it all leaked out I'll need to get that resolved before I get too boost crazy...saw almost 18psi tonight on the way into work

[kobuggy]

I was going to try the meth out last weekend, but have beveloped a miss fire above 4 lbs, I put new plugs in and set the gap to.025 from .030. No change, I will ohm out my plug wires next, they're Taylor wires from CB, any suggestions for a good supresion plug wire set? I'm using a DSM ignition system, it is set in a location that allows me to use type 1 length wires.