Just been reading on Twinturbo.net about a modification to the TBs that can achieve an extra 10hp, just wondered if anyone had any experience of it.

 

My limited understanding suggests that by allowing the butterflies to be less restrictive to the flow of air at WOT the gains can be made. It involves some filing of the TB and bending of the butterflies. What do you make of it?

 

Mark

 

Where is the link. Pentroof make a larger set of TBS for replacement.

Originally posted by 300z:

Where is the link. Pentroof make a larger set of TBS for replacement.

 

Not to sure how to direct you to the post - best thing is to do a search, this wasn't about a replacement - instead it is suggested that there is a 'limiter' that can be removed and by filing and bending the butterflies the POWER can be released.....

 

Mark

Surely though this would mess up the idle on the car? If you mess with the TBs then they won't seal on closed throttle and will therefore give you a bad idle....

 

Just a thought...

 

CheerZ,

 

Andy

Andy, you know how this sort of stuff works - have a look on TTnet, and do a search and see what you think - I would definately agree with what you are saying but the chances are I haven't explained it very well. The post does say that if you check the position of the butterflies at WOT they are not fully open - and I remeber noticing that when we were cleaning the TBs.

 

Mark

OK Mark have finally found it!!! Basically this is intended as a mod to improve air flow on an NA car - as far as turbo cars go, this wouldn't really give any benefits Maybe once you're pushing around the 600bhp figure then this could be possible but still uprated TBs would be a lot better

 

CheerZ,

 

Andy

 

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Andy

Knew you'd make sense of it!!!

Worth a try anyway.

 

ReZpect

 

Mark

I havnt looked at the mod but we used to do this on the 45 DCOE webbers that we used on mini's and escorts. (People who grew up in the Nova/Kenwood period are lost already ).

 

Surface grind the butterfly to half origional thickness and knife edge it, cut away the top half of the shaft, thin down the bottom half with a dremmel (file in the old days LOL) except for the little bits where the threads are.

Then replace the socket bolts for nice little round head ones.

 

I have some graphs in a book somewhere that shows it makes massive improvements in flow capacity, Its more beneficial on a N/A engine as your drawing the air in and want less restriction. I think it would benefit a tuned Z but not make much difference to a standard one IMHO.

 

Paul