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"reliably" Building Draw Through Turbo

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Currently in process of buying parts to build a 5k drawthrough turbo..

 

 

what I'm curious about is what are the finer details i may be forgetting about?

 

I'm thinking fuel pump and reg? would this be advisable or would this be useless in drawthrough?

msd boost timing thing?

 

what other items my be required that I'm not thinking of? apart from the obvious engine build parts?

 

i know drawthrough is not the best way, but keeping it old skool and i don't want to chop/drill or do any damage to my body

I love these old school set ups, and done right can work very well.

The standard fuel pump will be fine and a reg is only needed if using an SU which is advisable.

The turbo itself needs to have a carbon seal fitted so oil isn't sucked into the intake when you come off the throttle,

and keeping the intake path from turbo to inlet manifold short helps drivability.

The MSD for timing retard on boost is a very good idea also.

 

I'm doing a similar set up on a 63 hillman superminx, should be fun.

 

Good luck with it all and posting any of your findings would be good,

There is also a really good thread from some Volkswagen guys on this too, try the samba forum.

  • Author

http://www.rollaclub.com/board/topic/47686-complete-4k-turbo-setup-135kw/page__fromsearch__1 its that setup.. Planing on upgrading to a t25g seeing its going on a 5k.. But will try the t2 first.. And I need to find a 5k block!

 

 

Any idea on what fuel pressure I'll need.. Plan on 15-20 psi.. Looking for what regulator and pump will suit..

Edited by rke_011

In draw through pressure isn't really that important, its all about adequate flow. Don't think I'd use a standard mechanical pump. A Carter green or Holley red should be more than enough. Both make about 6 psi and around 60gph. Weather you need a reg or not depends on what carb you use.

 

I would say a t2 would be too small on a 5k. A t25g is nice and responsive but runs out of chuff pretty quick in the top end. Really depends on where in the rev range you want your power curve.

 

Also make sure all of the inlet tract from the carb is slightly down hill. You don't want fuel pooling anywhere.

Will petrol eat up the turbo seals? Another thing is that petrol mist might collect on the polished turbine blades and pool into droplets. That would decrease efficiency (the reason why you should never polish the inlet ports). Maybe rough up the blades with sand paper?

  • Author

Hmm good point.. Seals should be OK.. Has carbon seal t2 turbo... For now

pretty keen to see pics when its done

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