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wanted: instructions on porting a VF35 turbo waste gate

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Old 16 October 2008 | 07:44 PM
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From: Spec C Ltd 385/407
Default wanted: instructions on porting a VF35 turbo waste gate

as in title. are there any known threads or photos on how to do this.??

cheers
Andrew
Old 16 October 2008 | 11:34 PM
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The VF35 needs the wastegate port enlarged and the throat entrance to be opened up to allow a more direct entry for gases. I avoided taking too much away from the web between the turbine and wastegate as this can lead to cracking, although this happens more to the US VF39 and the VF43 on hawkeye cars.
You can also open up the flange area to match the up-pipe.
The hot side needs taking off form the compressor by undoing the band holding the two sides together. Some penetrating oil and gentle taps with a hammer should loosen them.

This picture shows the wastegate port being enlarged. Make sure you mark the limit of the penny so that a perfect seal is still made.
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From the flange end, this picture shows the inlet being matched for the up-pipe but the most important part is the removal of the obstructing throat area into the wastegate.
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This will need to be done with a die grinder and stones, followed up by a hobby drill to finish it off. A polished finish isn't needed and will add a large amount of time to the job.

nick
Old 17 October 2008 | 07:20 PM
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Any idea how much of a benefit this is ?. I already have Harvey's ported headers and matching UP plus semi decat exhaust. Wondering if I should plan on this in the future ??.
Old 17 October 2008 | 07:23 PM
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IMHO it's only necessary if you are experiencing boost control issues (?)

Mine was making 340 bhp and it wasn't a problem (bug-eye).

HTH

DunxC
Old 17 October 2008 | 07:40 PM
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Originally Posted by dunx
IMHO it's only necessary if you are experiencing boost control issues (?)

Mine was making 340 bhp and it wasn't a problem (bug-eye).

HTH

DunxC
I remember now that Harvey mentioned it avoided "boost creep" - I think ?. How would you know if you actually had that problem ?.
Old 17 October 2008 | 07:43 PM
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that's fantastic Butty. thanks very much.

the reason i was asking for this, was to upgrade from a TD04 on a MY99. i heard that porting will stop possible boost spikes.
Old 17 October 2008 | 08:01 PM
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Originally Posted by Keith Collings
I remember now that Harvey mentioned it avoided "boost creep" - I think ?. How would you know if you actually had that problem ?.
By seeing your boost going up and up beyond target level and then finding that the solenoid duty was at or near 0% (wastegate wide open).
This happened on my VF43 when a 3" decat was fitted. Timing was cut back and the advance multiplier went down to 0.6 - a warning to those who want to fit a decat to a hawkeye without remapping.
You'll never see the potential power that could be delivered and the engine will be at risk from regular detting.


nick
Old 17 October 2008 | 08:36 PM
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^^^^^

wow. it's definately technical stuff.. i think i might just save up a bit more and opt for a vf34 instead. feeling abit out of my depth now. but thanks again nick
Old 17 October 2008 | 10:38 PM
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Originally Posted by Butty
By seeing your boost going up and up beyond target level and then finding that the solenoid duty was at or near 0% (wastegate wide open).
This happened on my VF43 when a 3" decat was fitted. Timing was cut back and the advance multiplier went down to 0.6 - a warning to those who want to fit a decat to a hawkeye without remapping.
You'll never see the potential power that could be delivered and the engine will be at risk from regular detting.


nick
Thanks - so if I understand this, the problem is that the wastegate cannot release boost quickly enough which causes overboost even through the wastegate is open. This is likely to show when target boost levels are set high and a more efficient exhaust is fitted which supports quicker spool up and thus increases the load on the wastegate ?.

I don't know how to measure solenoid duty but have an Apexi FC with Commander - so I guess if it does not exceed max boost, then I am not seeing the problem ?.
Old 17 October 2008 | 11:40 PM
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Originally Posted by apac
^^^^^

wow. it's definately technical stuff.. i think i might just save up a bit more and opt for a vf34 instead. feeling abit out of my depth now. but thanks again nick
I had to have my Vf34 ported to stop boost creep, apprantly a common fault on Vf35/34 when using full de-cat exhaust.
I did have some good instuction on how to modify them, it the path to the wastegate flap that needs smoothing out.

The instruction i had said that the opening by the flap show in the photo should NOT be altered
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