Hi,
You asked me about the vt brake upgrade for your vs...you have 2 options...
1.keep your original single diaphram plastic booster and bolt up a vt/x/y master cylinder to it but you have to remove/cut off the small bolt on the pushrod where it contacts the master cylinder to get the right freeplay and bolt up the vt//x/y cylinder with your old vs reservoir fitted to it so it looks right.
2. fit a modified vt/x/y dual diaphram booster and everything bolts up like factory again with the vs reservoir fitted.
I have one setup like option 2, done finished ready to go and I have sold a few in the past if you want to get one from me...I currently have the same setup on my daily drive.
Also with the vt/x/y calipers, pad choice can have an effect how well your car stops

Cheers
Mark.

If its an issue with the BB-TB, surely some one else has had the same issue.

has any one seen this before?

any help would be awesome!

what I've Tried & more info;
The problem is basically that only when the BB/modified throttle body is on the flareing is experienced.

* It may be important to note that the modified throttle body is from a wrecked VT,
......... yes i fitted a new VS SII TPS.

(I could see absolutely no difference between them.)
I've tried my old memcal with my spare PCM - no change

tried my throttle body on friends VX same thing.....(thats when i sent it back to be checked by fitter who did the mod.... just to add he is a highly qualified mechanic at the holden.)

I'm ok with buying a new one if the throttle body is the issue,
However..........
as many of you are probably aware, buying new parts just to see if it fixes the problem, can end up being an expensive investment into a cardboard box of "spares".

mods on car so far; (I'll list em all in order of what i feel may be most relevant)

* BB throttle body (made by a Fitter I know who has made several successful of these so far except mine), He has re-checked his work since and can't see a prob.
* Transmission rebuild + stage 2 transgo shift kit. (professionally$$$)
* Mod memcal - EBAY Blackstar 7000 (thats the seller)
* Air Hog Filter
* Super charged cold air intake
* Extractors
* 2.5" sports exhaust & hiflo Cat
* REPCO thermo fan controller
* wheels, struts, springs
* lots of stereo stuff i'm assuming is irrelevant.
* Superficial and facia

Hi all, A BIG PLEASE HELP! - big bore Throttle body MOD issue



From what i have read this problem seems unique so here goes.

Symptom:
Transmission flare, most prominent in 2-3.
only when big bore throttle body is fitted.
first shortish test run is usually fine, but another couple of runs and it gets worse and gradually worse untill its happening in all gears.