Finally got my VDO boost gauge!

[appletonn]

Went out 'playing' last night - firstly to check that I hadn't got any leaks anywhere and thus actually reached positive boost!

The temptation to fiddle with the boost levels now that the controller is within easy reach, may prove too much to resist!

Last night, set it to achieve 15psi at full throttle in 3rd gear at around 4000 rpm. Next stage this weekend, will be to increase that to 16psi, for now![]

...or 1.1bar in new money...[]

 

[Diver944]

ORIGINAL: appletonn

Last night, set it to achieve 15psi at full throttle in 3rd gear at around 4000 rpm.

Our cars normally make more boost in 4th gear so you really ought to be setting it in the same gear. I know that speeds in 4th will be a lot higher [] so this is more difficult to do on most of our private driveways

If you set it to 16psi in 3rd gear then in reality you may hit 17 or even 18psi in 4th, which could be worrying for your head gasket if your chips don't provide enough fuel at 18psi.

 

[appletonn]

Ok, thanks Paul.

I did do a couple of runs in 4th gear from around 3500rpm and it didn't appear to exceed 15psi, although it's not easy to read the gauge and not crash at the same time!

Will persuade my better half to ride shotgun at the weekend[]

So 4000rpm in 4th at full throttle should show peak boost?

 

[Diver944]

Peak boost wil be entirely dependant to what you set the black knob to and how strong your turbo/ wastegate setup is. However, strictly speaking your K26/8 and DPW should hit 16-17psi by around 4000rpm and then gradually bleed boost off to be around 12psi by the red line. You could probably reach 20-21 psi but it would still bleed back to 12psi by the red line. I found a chart for Jason Lathams car on Ricks website and his car is virtually identical in mods to yours. Here is his boost chart:

 

[appletonn]

Thanks Paul.

Jason's car appears to hit just shy of 17psi at around 4000rpm.

I will be going to work in it tomorrow, so will have 40 miles down the M6 with which to set it to 16psi with the MBC[]

As Andy at Promax recommended that I shouldn't really exceed 1.2bar with the chips fitted to mine, I'm going to err slightly on the side of caution and aim for 16psi for now.

It is going in to have a full suspension set-up next Tuesday, including corner weighting etc, so hopefully it will be the finished article in time for Le Mans!

By the way, I can heartly recommend the LR 3" downpipe exhaust with the stainless RPM back box - it makes a great noise (for a 944) and pops and crackles when you lift off too[]

I know, I know, I'm a big kid, but aren't we all?![8|][]