Twin sprintex sperchargers

[chapperssx]

Here's a little project for someone,when the SX cars were made TVR was looking into a 4.5l twin supercharger setup http://cgi.ebay.com/ebaymotors/SPRINTEX-TWIN-SUPER...

[dbv8]

Gimmick?

Twin turbos i understand but why the need for twin SC?

[JR]

Worked OK for AM: http://www.aston.co.uk/carsales_index/php/action/d...

[grahamw48]

Might even trade a Wedge for this one.

http://www.youtube.com/watch?v=7sTVwrOjMn4&fea...

[combine]

I think you'd need some traction control with such a beast , wedges are hairy enough in normally aspirated form !

[GV]

I'd think they would end up melting everything under the engine bay....!

[adam quantrill]

dbv8 said:

Gimmick?

Twin turbos i understand but why the need for twin SC?

It is because of capacity - the sprintex I have is good for 4l but only just, as the boost drops from 6 psi to 4.5psi as we hit 5200 rpm. At that engine speed the s/c is almost hitting it's max rpm - 15000. For bigger engines you would have to spin the s/c faster to pump more air per second. This means gearing up the drive, and the upshot is that your engine max RPM is determined by the supercharger.

However if you stick two blowers on you can blow twice as much air at the same RPM.

[dbv8]

adam quantrill said:

It is because of capacity - the sprintex I have is good for 4l but only just, as the boost drops from 6 psi to 4.5psi as we hit 5200 rpm. At that engine speed the s/c is almost hitting it's max rpm - 15000. For bigger engines you would have to spin the s/c faster to pump more air per second. This means gearing up the drive, and the upshot is that your engine max RPM is determined by the supercharger.

However if you stick two blowers on you can blow twice as much air at the same RPM.

My point was, it just complicates matters. I realize the sprintex (as chosen by the late Mr Haughin from my home town Barrow-in-Furness) was suited to the 350 for a mild amount of boost which was fine in a wedge some 25 years ago.
Rather than mess with the complexities of fitting twin it would be far simpler to just fit a bigger SC.

Having said all that i must admit i do appreciate peoples efforts to do things a little different. Not many people would do what ive done to my car!

[adam quantrill]

Agreed - it looks bloody complicated.

One benefit though is if a belt snaps you still have the other s/c driving - so it's less of a problem.

[Alexdaredevilz]

Correct me if im wrong, but using two chargers means you could have them spinning less to create required boost, thus removing the problem of dimishing returns of heat you can get with chargers

[adam quantrill]

I would have thought with that size of engine, both chargers would be pushed to the max to flow enough air.

[Jasper Gilder]

I have the definitive answer as I was with Dave Haughin when he took a call about supercharging a Tuscan Racer ( 4.5 Rover). He told the guy it would be twin Sprintexes. When I asked him why he explained in his very best don't mock the afflicted tone, that a standard Sprintex did not produce enough volume and the Sprintex he was using was the biggest Fleming Thermodynamics made

This was a matter of weeks before the breakdown that eventually led to David's sad death so the car never got built. Meanwhile Aston stuck two superchargers on the V600 Vantage ( and then extra gears and trick final drive to get the MPG over 18)

[adam quantrill]

Here's another little project - with some Peter Wheeler heritage to boot:

fleabay