Neat supercharger conversion on the RV8

[eesbad]

http://www.pistonheads.co.uk/sales/1152731.htm

Not sure the front pulley would clear the bonnet on a wedge though and a 90 degree elbow would be needed at the back, but neat looking conversion with no plenum.

[grahamw48]

Hmm....looks interesting.

I'd be wanting a lot more than 300bhp with that lot.

Might as well fit a modern turboed unit for even more power and better economy, much as I like V8s, and obviously all that torque is hardly needed in such a lightweight projectile, so bit of an oddity really unless you plan on hillclimbing it or towing a caravan.

Not much money though.

[B@man]

That looks like a Jag or US Charger very neat install !

Re: before you chuck yer V8 and replace it with a turbo'd 1.6 valver, doesn't the saying go something like :

"BHP wins bar room arguments but Torque wins races !"

Edited by B@man on Thursday 23 July 14:03

[Transmitter Man]

Twin turbo V8's are better:

http://www.bankspower.com/techarticles/show/4-twin...

Phil
420 SEAC

[GreenV8S]

I spent a good while drooling over that before I started on mine. From memory it's an M90. Unfortunately with that configuration it hangs quite a long way over the back which could be a problem in the wedge and impossible in any of the later RV8 TVRs. The bigger M112 is longer and would be even worse from that point of view. Fortunately we have much wider engine bays than that so it could be fed from the side, in fact I seem to remember that the blower inlet manifold was a modified ATI part that was originally fed from the side.

[grahamw48]

B@man said:

That looks like a Jag or US Charger very neat install !

Re: before you chuck yer V8 and replace it with a turbo'd 1.6 valver, doesn't the saying go something like :

"BHP wins bar room arguments but Torque wins races !"

Edited by B@man on Thursday 23 July 14:03

Well, mine definitely has 251 lbs of torque...great for going up the hills of N.Yorks.

[Brap_Brap]

grahamw48 said:

Hmm....looks interesting.

I'd be wanting a lot more than 300bhp with that lot. Might as well fit a modern turboed unit

If you could intercool that it would be far better, which is why I'd go for a
ProCharger http://procharger.com/ You can intercool it. It responds like a turbo with
less lag, and you don't have to modify that glorious noise by making it spin turbines.

Edited by Brap_Brap on Friday 24th July 01:06

[Brap_Brap]

B@man said:

"BHP wins bar room arguments but Torque wins races !"

That's only because races aren't straight and flat for mile after mile.
On the salt at Bonneville my humble street ported/lightened 1.3L naturally
aspirated rx7 would catch up to, then pass my wedge easily. I've already had it
at a speedo indicated 147mph, in 4th @ 8000. My rotating assembly is rx8 bits rated
for 9k rpm but spark cuts out at 8k

I would ALSO point out I'm doing 147 MPH in FOURTH with one more gear to go....lol
on a 4:10 rear end.... lol... and the gear drop is at least 1200 rpm, it's a tall final gear.

Bye wedge... I hate to say it, but it's true.

[B@man]

Brap_Brap said:

Bye wedge... I hate to say it, but it's true.

What a wankel

Sorry couldn't resist it

[Brap_Brap]

Yes, the underestimated wankel.

Although it will cost me 3 times as much fuel.

And if I bought the 4:30 rear set, I'd murder my wedge for acceleration too. (as well as high end)
http://racingbeat.com/resultset.asp?PartNumber=130...

Don't get confused with the odd rx-7 you may have embarrassed with what and rx-7 CAN DO with almost $11k invested into it.

edit: and what is torque anyways? People always like to say how x# hp means less at the wheels. This is true. It is NOT TRUE with torque. In fact it's often the opposite and is dependent on gear/diff ratios.

For instance the Peterbuilt I drive for a living has in the neighbourhood of 2000 lb/ft of torque at the FW, but in the lowest gear, over TWENTY ONE THOUSAND pounds at the wheels.

To all the "temple of torque" proponents out there, I would remind you Einsteins theory
of relativity still holds true.

Edited by Brap_Brap on Friday 24th July 08:13

[grahamw48]

Let's not forget that our Wedges are 'standard' cars.

Spending what the 'tuners' spend on their mass-produced tin boxes might also add slightly to the performance of our machines too.

[chedder]

Interesting stuff,it is possible to side mount the Eaton M90 in a Wedge (pre serp) and intercool it too, I know because I have done it to my 3.5L
Not running a lot of boost at 4psi due to the stock bottom end and pistons, however I can confirm that the torque is excellent at 330lbs, exceleration is excellent with 0-60 in under 5 secs.
M90's are relatively cheap too, always a few for sale on Fleabay USA for around £200, rebuild kits, spares and upgraded pulleys are cheap and available too.

Chedder

[Poledriver]

I've got an M112 ready to cobble into my Wedge later this year but have been advised against bolting straight to the inlet manifold as:-
a) it needs intercooling
b) you can't get an even distribution to all cylinders, the rear cylinders get starved of fuel.

Can anyone confirm/deny the above? I've been told tyhis from quite a few sources so was surprised to see the Westie!

[GreenV8S]

Poledriver said:

I've got an M112 ready to cobble into my Wedge later this year but have been advised against bolting straight to the inlet manifold as:-
a) it needs intercooling
b) you can't get an even distribution to all cylinders, the rear cylinders get starved of fuel.

Can anyone confirm/deny the above? I've been told tyhis from quite a few sources so was surprised to see the Westie!

One of the well known RV8 suppliers makes these comments quite prominently on their web site. By coincidence, they specialise in supplying highly tuned normally aspirated engines, and don't sell supercharger conversions.

The comments about distribution I believe stem from a conversion that was offered for range rovers (from ATI I think) that mounts the blower straight onto the bottom of the trumpet base with almost no space between the blower and the ports. Since the blower outlet wasn't positioned centrally on the engine the front cylinders didn't get as much boost as the rears - this caused the rears to run lean and hot.

This is a problem specific to that one kit, although from the web site comments you might get the impression it's a general problem. Various others have successfully mounted the supercharger in the valley. Some of them connect the blower straight into the inlet manifold, others add space for a shallow plenum with a charge cooler in it. Mine uses a slightly different approach and has the blower outlet at the top (i.e. the conventional Jaguar orientation which allows for an external charge cooler. (Adding the charge cooler is still on the 'to do' list.)

[eesbad]

Poledriver said:

I've got an M112 ready to cobble into my Wedge later this year but have been advised against bolting straight to the inlet manifold as:-
a) it needs intercooling
b) you can't get an even distribution to all cylinders, the rear cylinders get starved of fuel.

Can anyone confirm/deny the above? I've been told tyhis from quite a few sources so was surprised to see the Westie!

Well he quotes Dennis Priddle as the maker of the modified inlet manifold, and he knows a thing or two about supercharging... He was behind the original SX wedges (DPR at Yeovil) IIRC. But I have also heard the same concerns as you have.

[Poledriver]

GreenV8S said:

Poledriver said:

I've got an M112 ready to cobble into my Wedge later this year but have been advised against bolting straight to the inlet manifold as:-
a) it needs intercooling
b) you can't get an even distribution to all cylinders, the rear cylinders get starved of fuel.

Can anyone confirm/deny the above? I've been told tyhis from quite a few sources so was surprised to see the Westie!

One of the well known RV8 suppliers makes these comments quite prominently on their web site. By coincidence, they specialise in supplying highly tuned normally aspirated engines, and don't sell supercharger conversions.

The comments about distribution I believe stem from a conversion that was offered for range rovers (from ATI I think) that mounts the blower straight onto the bottom of the trumpet base with almost no space between the blower and the ports. Since the blower outlet wasn't positioned centrally on the engine the front cylinders didn't get as much boost as the rears - this caused the rears to run lean and hot.

This is a problem specific to that one kit, although from the web site comments you might get the impression it's a general problem. Various others have successfully mounted the supercharger in the valley. Some of them connect the blower straight into the inlet manifold, others add space for a shallow plenum with a charge cooler in it. Mine uses a slightly different approach and has the blower outlet at the top (i.e. the conventional Jaguar orientation which allows for an external charge cooler. (Adding the charge cooler is still on the 'to do' list.)

HMmmm Might rethink this, it makes for a much nicer installation fitted in the valley, still can't quite visualise how to get the compressed/cooled air into plenum. How much power will I lose if I pre-cool air before blowing instead of after?

Edited by Poledriver on Friday 24th July 13:29

[GreenV8S]

Poledriver said:

How much power will I lose if I pre-cool air before blowing instead of after?

You more or less can't - you can't practically cool the air until it's been heated.

If you're only running low boost you will find you get better results from water injection rather than a charge cooler, since this avoids the pressure drop across the charge cooler and also gives in-cylinder detonation protection.

[Poledriver]

GreenV8S said:

Poledriver said:

How much power will I lose if I pre-cool air before blowing instead of after?

You more or less can't - you can't practically cool the air until it's been heated.

If you're only running low boost you will find you get better results from water injection rather than a charge cooler, since this avoids the pressure drop across the charge cooler and also gives in-cylinder detonation protection.

This is all starting to fall in place a lot better than my original plans, I'll be running 5-6 psi boost so could save a lot of awkward plumbing of large diameter pipes in the bay!

Googles water injection!

[GreenV8S]

Poledriver said:

This is all starting to fall in place a lot better than my original plans, I'll be running 5-6 psi boost so could save a lot of awkward plumbing of large diameter pipes in the bay!

I'd be very interested to see how you get on. Where abouts are you based?

[Poledriver]

GreenV8S said:

Poledriver said:

This is all starting to fall in place a lot better than my original plans, I'll be running 5-6 psi boost so could save a lot of awkward plumbing of large diameter pipes in the bay!

I'd be very interested to see how you get on. Where abouts are you based?

Near Havant in Hampshire