The Superboxer, a new heart for the Silver Bullet

[silverbullet]

Had a look at the G60 throttle body and now I see the mechanical bypass that appears to re-route the compressor discharge to the upstream side of the throttle discs?
If so, that is more like the racing application: more efficient but also more risky because a backfire can blow the throttle body or bend the spindles...

[max and caddy]

Yes...I guess a backfire would cause a sudden pressure rise in the inlet...but unless it's made of plastic I would of thought it would be able to handle it...or fit a blow off valve of a similar design to the JX diesel one maybe? It's never a problem on the G60 engines anyway...a suggestion anyway...

[silverbullet]

All good stuff, food for thought and all that. Found a pic of an exploded throttle body... I have searched for a G40/60 inlet air flow path diagram or brochure cutaway drawing that shows the bypass but no luck so far.
Not a fan of blowoff valves on petrol engines, dumping metered air and flames out the exhaust.
Whoosh! Pop! is for kids.

[max and caddy]

I have lots of G60 stuff...what do you want..a diagram?...G40 is different again and won't bolt straight on in place of the 2.1 watter user part.

[max and caddy]

Google...VW ssp 103... it's all there in germanish ...there is an English version as well but can't see it..easily..

[silverbullet]

Cheers. Straight bolt-on was a long time ago...

[max and caddy]

Maybe it would all be a bit more pure if a G60 lader was used...are those jag plenums charge coolers?

[silverbullet]

This screw compressor pisses all over the G lader I am sorry to say. Efficiency of 80-85% compared to barely 70%
Those are indeed chargecoolers, I have to make new plenums for their undersides. Looking forward to that, lots of ally carving and contouring.

[silverbullet]

As for "purity"... its getting surgery for that UN1 and it will need it too

[silverbullet]

Curiosity got the better of me, so I put the -08 ratios into the Westfield gear calculator
http://westfield-world.com/gtc.html" onclick="window.open(this.href);return false;
1st 3.36
2nd 2.05
3rd 1.38
4th 0.96
5th 0.76
Final drive 3.778

Looks like it will comfortably hit 80 in 3rd before it redlines...

[silverbullet]

It gets better!
Working from the "factory declared" Cd figure of 0.44 for a tintop and a frontal are of 3.06m2 (33 sq ft) and a weight of 3200 lbs, stuff all this into some of the online calculators and they all come out with around 270bhp (inc tyre drag) being needed for 135mph!
If the frontal area figure is modified to allow for the sloping front or smaller mirrors, undertray etc (say a modest factor of 0.9) then the top speed goes up to 140...

I am building the engine for peak power at 5500, redline at 5800 so this looks about right for the new gearing:
5500 rpm in 5th = 145mph

Of course at this speed the brakes will need to dissipate twice the energy in braking compared to 100mph

PS the same calculators indicate that a T3 needs circa 135 hp to do 100mph, which would tally with the new car performance data for the SA 2.6 and also my own real-world experience from when this bus had the EJ22 (although it struggled make full power revs in 5th due to a full load misfire)

[silverbullet]

A bit more handy data which gives some idea of what the UN1 was designed to handle (i.e. used and abused, as is the French way)
http://www.autoevolution.com/cars/renau ... rbo-205-hp" onclick="window.open(this.href);return false;

My one is happily the later version: a tell-tale core plug on the front housing indicates an internal oil feed to the 5th pinion, as well as neat details like a spring-cushioned selector for engaging second gear

[scimdiesel]

At 130 mph I recon the windscreen might push though... Mind I recon I might follow though as well.

[silverbullet]

There are faster T3's around

A bit more reference material http://www.lotusespritworld.com/EGuides ... arbox.html" onclick="window.open(this.href);return false;

[mrhutch]

There are faster T3's around

When MadMatt took me out in his S4 bi turbo powered bus I nearly stained the seats at 110mph. it took very few seconds to pull from 30 to 110.