alternatives to Jenvey ITBs?

+7bhp

 

@Nige , if you were to build another itb'd track car, would you do the same again, or buy an off the shelf solution?

 

Personally ? I`d do the same. I enjoyed the fabrication and whole build. They never looked as good as bought ones, but once I added some proper aluminium velocity stacks, they were fine. Like most of the diy projects that happen on here, you need to do quite a bit of legwork and fabrication yourself, but I find that enjoyable. Being shown how to map by Eddie and taught me so much. I know others have turned up and he`s tweaked it for them on dyno days to get their setups running smoothly, but not being local, i`m not in a position to be able to do that, so I learned all I could that first time and have beneffited hugely from his teachings and subsequent on the road / track tweaks.

A small point, if you build it yourself, you are, in my experience, more likely to be able to fix minor issues yourself, rather than just having a bought system that breaks and you have no idea what to do to fix it.


However, the downside with bike ITB`s is sharp throttle response at low revs. You get used to it, but it can be a bit tricky at first. Car based ones, like Eddie is fitting at some point are much better in that respect.

 

Yeah Mike is a nice chap, he and I were at Loughborough Uni together on the Automotive Engineering Degree course

 

And maybe the same again if you tip them forward and add more length. . .

 

Copyright Laws allow for something called Fair Use
If someone had claimed the picture or vehicle was their it would be an issue, but to show something in context with no claims pretty much make it free

And that seals it

 

Tom (smudge) made different/larger throttle cams to make the throttle openings more progressive on his bike jobs at the time.
I was aware of this and had a set of bike ITBs but, did not have the skills like Tom to re-engineer this area. So instead, as I had worked on many a JDM AE101 GT Apex, Marino and Ceres in the mid 90s, opted for the Toyota ITBs. The base systems that I now have were donated to me from a long time friend aboard.

I know trackcab16v's son, Kevh, has a set of SR20DET GTIR jobs on his 16v MK1. Unlike the Toyota ITBs the bore spacing to a tad bit different on a 16v. But that also works.
Trackcab16v has got a set of BMW E30 M3 jobs on one of his 200+ ps monsters!

So in addition to the established brands you also have quite a lot of home grown stuff owned by many a Club GTIer.

 

That is true, it is more sensitive (especially when you have a short stroke V6), and yes you can engineer around it with a non-linear throttle action
Never really worried about it personally because my throttle only has 2 positions