I was a bit worried about the bottom end, but today the proper exhaust went on and I overhauled the boost control and the sound and pull from 3500-7000 RPM is just incredible. It has lost out low down until 3500 RPM - in some places by 4-5 PSI, but in comparing the airflow and boost in a 3rd gear drag run with a car with a highly rated manifold even considering I have a hybrid TD04L (which is laggier) there is certainly no disadvantage in boost or airflow from 1500 to 3000 RPM. After that I am running much higher boost (20 PSI) so the figures are not comparable, but I have seen the highest ever airflow readings on my car since fitting this manifold from 3500 to 7000 RPM. You really need a full exhaust to make the most of this manifold - it did not feel good without it. I expect with the VF23 it will be even better and the losses low down will be less significant because a VF23 is not going to be making big boost below 3000 RPM.

Whatever, the theoretical objections or misconceptions re manifolds, this one works on my car - and I haven't touched the fuelling yet which seems to be leaner still during spool up so work there should unlock some torque.

Good for you.

Let us know how you get on with the tweaking, sounds like you is getting seriously quick. :)

Is the ss manifold their own design or are they much of a muchness?

I did see one at PE one time but that was about £1000, bit much for me.

:)

Great Stuff John!

Glad they are working to your liking!


Now can I have them back please ;)

Neal

John/Pete,

Is this Scoobysport manifold being 'development tested'or is it ready for sale? If so, how much does it cost?

Pie.

No-one answering then?

Please answer, it sounds interesting

I got it second hand from Neal Gibbons. It is an established product. I don't recommend it on a small turbo or without a full exhaust. It is perhaps something to add when you have done a lot of other things.

Its something we developed 2 years ago with Hayward and Scott. It uses the features that they gleaned from R&D work with Lotus, Cosworth and Ford Racing, adapted to suit an Impreza engine. As John says, it should be used in conjunction with a full exhaust and re-map. Its designed to give maximum performance increases in the 4000-6000 rpm range.

£910+vat.

Ok, thankyou gentlemen.

Regards.

Happy because I now managed to get 20 PSI at 2900 RPM with the hybrid TD04 and the manifold, and airflow and acceleration are respectable too :) This is only 200 RPM higher than previously. 30-70 times averaged are about 4.35s logged from the speedo output on Delta Dash, so they are a bit optimistic - maybe 4.5? Fractionally better than before, but the errors in the gearchange and the timing are present. Subjectively the car feels much quicker above 3500 RPM than it ever did before. Delta Dash airflow meter voltages are up to 4.42V.

Out of interest John, what did you do to the map to achieve the earlier spool up?

Neal

The fuelling seemed OK in the end and I have not yet advanced the ignition any more than previously - probably won't as it was quite advanced already.

I ran a 91% duty cycle on a 1.1mm restrictor up to 3000 RPM. Ran less from 3000-5000 RPM then 91% again to red line. It was boosting better last night as I set it up in the cooler evening, but this is when I did most of the previous mapping, so the 200 RPM offset is comparable.

It is the usual thing of not making it too frisky so it overboosts - still some work to do on it, but in the heat of the day the boost is more sluggish than at night, but comparing like for like it has lost not a massive amount on spool up. Even though I reach full boost only 200 RPM later, the boost starts to develop later, but then it comes in with a big turbo style bang and the torque seems to follow the boost closed than before. With the big turbo (whichever I end up with) I think it will be magic.

I've done a wee bit of driving/dabbling with my new iON Performance 4-1 header.

I used to get 1.3 bar around 3400 rpm with the OE manifold (stock VF23), it's about 300 rpm later now, and after 4000 it *really* kicks in, and it just wants to rev on after that.

The 4-1 is a pure topend system - and I was aware of the fact that I was going to loose a bit of lowend...but that's just an excuse to rev it a bit - it does have a few aural benefits. ;) :D

/J

P.S. Just wrapped the sob with zorstwrap - and the smell IS indeed offensive - and it's smoking alright... :D