dowser

Hi All,

Fitted a locally sourced 4 into 1 manifold + up-pipe to my VF23'ed my00 over the weekend.

The car now pulls very, very (,very ) hard once on boost - the problem is that I don't get boost until much later.

With just the VF23 and OE ported headers/up-pipe I had 1 bar by 3k, it's now 3.5k.

While I expected lag to increase, I'd hoped not by this much Has anyone got similar results after doing the same? The JECS will be remapped soon, and while I expect things to be improved with this I don't see how it will be able to reduce the boost threshold enough (I have Dawes currently).....I'd kind of set myself a 1bar at 3k target....

Problem is I just use too much petrol like this - once you've dropped a gear to accelerate it pulls so well you just keep going, lol!

Thanks
Richard

Pavlo

I would like to see some before and after delta dash logs for these manifold upgrades. I wonder if leans the engine out at all, shouldn't I know, but you never know.

Strange thing is, Stephen Done's car did very well with the manifold, even low down. But bigger turbos seem to be the thing that causes boost to come in (a little) later.

I hope the remap improves things.

Paul

dowser

I'll email you logs tomorrow - left laptop at home today

Fuelling is OK, it's just the slow response - once turbo is spooled I'm seeing up to 4.5 volts from the MAF

I think it just shows the inherent compromise of squeezing performance from an engine - you either get good low down and run out of puff, or good top end but nothing below. Anyone know a good sequential set-up?!

Mind you, I should also add that I'm still using standard airbox and inlet pipe plus the original cat'ed centre section....currently!

Not decided what I'll do yet, will wait for the remap, but a distinct possibility will be swapping the manifold for track work....getting quite good at it now, two of us swapped the up-pipe/manifold (requiring d/p removal too) in 1.5 hours Friday...and the manifold itself is only 8 easy to access bolts

Richard

nom

Isn't the VF23 a 'power up top' design, and the 4-1 manifold is as well (I'm positive about that one!). So it's actually all behaving itself...

Pavlo

Not all mods that add power high up loose low down torque or spool up, eg backbox.

THe factory map is quite lean 1200-3000rpm, by that I mean it seems intentionally lean.

Paul

john banks

You won't get the boost threshold substantially lower than the Dawes, but will benefit from improved fuelling and timing from 1000-3000 RPM in particular.

My car has lost out low down, but my airflows are similar to Stephen's despite a hybrid TD04 compared with the original TD04. When I was on the original headers it had considerably more boost and airflow low down than Stephen's car, so I think if you mapped the car properly with and without the headers will give you about 200-300 RPM higher boost threshold. They have more volume.

[Edited by john banks - 7/15/2002 10:06:57 AM]

dowser

Two weeks to wait then, then I can assess next steps.

Nom - agreed, I expected this issue....doesn't mean I have to like it though

The up-pipe I've fitted has quite a step down in size about 10cm from the turbo mating - I'm trying to find out whether this is intentionally done to speed up the gases (and if it was, then it must have been done with the td04 in mind?). So I'm also trying to work out how a larger bore all the way to the mating of the turbo would affect things....probably only way to know for sure is to try it.....

Anyone know how the Scoobysport up-pipe reduces in size? The 4-1 design I have is large bore where the 4 pipes join, continues through the junction with up-pipe and reduces before the turbo.

Thanks
Richard

nom

From a 'simple inspection' (from memory too - the thing isn't sitting in front of me at the moment ) it's some cunningly bent tube. No steps nor nuffink. Except for this annoying M12x1.25mm (I think that's the size) thing in it for the sensor I don't have... Actually, anyone know where I can get a plug for it while you're here?

nom

Yep, internal di is 54mm (2 inches?) the whole way through.

dowser

Thanks Nom,

I feel some experimenting coming on!

Richard