A buddy of mine is looking for a turbo for his drag beetle... suggestions?

[GrimJack]

Here's the specs he quoted me:

I am trying to look at what turbo(s) I should be looking at buying (eventually) for the new Beetle motor. I am not well versed at turbo application stuff so want to get an idea of what would work. 2850cc, 30-35 lbs boost, 8200 max RPM, methanol, single turbo, non intercooled, EFI and would like to make a safe 800+ RWHP.

Any suggestions?

 

[Poodles]

Things like this help: http://www.not2fast.com/turbo/glossary/turbo_calc.shtml

Methanol fuel is a bit weird though, so I have no idea to be honest.

 

[IJ.]

35lbs, non intercooled, safe..... hmmmm ok :nono:

 

[4U2QUIK]

Methanol changes everything IJ.

 

[IJ.]

Methanol changes everything IJ.

Only to a certain extent, can't change it's still a Dak Dak (VW)

 

[Poodles]

For a drag car I can see it happening as it doesn't have much time to really heatsoak. It's still an odd sounding setup and hell, and intercooler is easy to install, air to water works good for drag cars since you can throw icewater in there.

 

[GrimJack]

I've seen quite a few drag cars here with no intercooler. I've never managed to figure out the reasoning behind it - whether they simply tune for the excess heat, or whether the fuel they are using drops the intake charge temp enough by itself.

It's the methanol that's playing havoc with my head. Meth has a fair bit of oxygen built into it, as shown by it's formula, CH3OH, unlike regular gasoline, which means that not all the oxygen needs to come from air compressed by the turbo. However, I don't know enough about the chemical reaction during the burn for either fuel to figure out any kind of ratio. Otherwise I'd just suggest any 800rwhp capable turbo.

 

[4U2QUIK]

Only to a certain extent, can't change it's still a Dak Dak (VW)

Dak Dak lolololol rofl so true. Only reason why I know VW's is because I had a roomate that's a vw nut for several years ,a and I've managed to buy/sell them for money just by knowing what to look for. Other than that I've hardly even driven them. I can't stand the dak dak dak and the vibration and the utter lack of power, even when they've been hopped up.

For a drag car I can see it happening as it doesn't have much time to really heatsoak. It's still an odd sounding setup and hell, and intercooler is easy to install, air to water works good for drag cars since you can throw icewater in there.

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
kinda what I was thinking also.

I've seen quite a few drag cars here with no intercooler. I've never managed to figure out the reasoning behind it - whether they simply tune for the excess heat, or whether the fuel they are using drops the intake charge temp enough by itself.

It's the methanol that's playing havoc with my head. Meth has a fair bit of oxygen built into it, as shown by it's formula, CH3OH, unlike regular gasoline, which means that not all the oxygen needs to come from air compressed by the turbo. However, I don't know enough about the chemical reaction during the burn for either fuel to figure out any kind of ratio. Otherwise I'd just suggest any 800rwhp capable turbo.

In a VW it will probably work great. The stock intake design has serious icing issues if you don't run the intake heater setup. With methanol this problem gets worse as methanol can act as a minor refrigerant. But under Boost conditions, I dunno.
afr for methanol ( 6.4:1) is even lower than ethanol at (9:1) so you're also using a LOT of fuel.

You may also find it interesting that methanol and ethanol both have a very low air-fuel ratio, and the carbon chain length is comparable to methane and ethane. The reason is that alcohols like methanol and ethanol already carry oxygen themselves, which reduces the need for oxygen from the air.