S/C Installation all done - Up and running, WOOOOOSH!!!

Gibbo · 8 Nov 2006 at 10:05

D4VE said:
Sounds good, what boost is it running?

You may find it makes most of its boost at half throttle hence why its so quick like that.
My Rover turbo made most of its boost at half throttle, so going to full throttle only yielded a bit more performance.

Sounds awesome though, not many cars have more than 350bhp/tonne, you wont get beaten often unless you regularly come up against Ferrari F40s etc

HI m8

Its got a 3.60 pulley (7.5psi) engine bottom end can cope with upto 10.5psi before it will blow something. However as most of these setups they tend to make a little less than full boost. So I expect its probably making 6-7psi.

Its raining today so have driven all the way to work in 4th at around 1500rpm, still even pushing the loud pedal at that is scary fast.

Gibbo · 8 Nov 2006 at 10:08

rayb74 said:
How did you lower the compression Gibbo? Or do cars with large capacitys not need to worry?

The engines compression is already low, so no need to. Plus as these cars come from the factory with superchargers fitted and the company who supplied my kit having already done over 400 installations I think its needless to say I am in quite good hands.

One guy was running 700BHP before the engine went on stock internals, then he just put a stroker in and is making around 800BHP now and is soon going to add ***.

My main worry was the clutch but it seems thats also fine upto 600BHP before it will start wearing fast.

Phil W · 8 Nov 2006 at 10:10

What are the wear rates & replacement costs on consumables such as tyres?

I'm classing them as consumables as i'm assuming they don't last all that long when giving it stick?

Gibbo · 8 Nov 2006 at 10:16

Phil W said:
What are the wear rates & replacement costs on consumables such as tyres?

I'm classing them as consumables as i'm assuming they don't last all that long when giving it stick?

Hi there

£250 each on the rear and £260 each on the front. Not too bad but I do get trade and cash price on tyres.

Sone · 8 Nov 2006 at 10:18

Gibbo said:
Hi there

£250 each on the rear and £260 each on the front. Not too bad but I do get trade and cash price on tyres.

lol before the michelen "closed" everyone in stoke got trade and cash price for tyres

Gibbo · 8 Nov 2006 at 10:21

Sone said:
lol before the michelen "closed" everyone in stoke got trade and cash price for tyres

Hi there

I don't get my tyres from their, the place aint even in Stoke.

Phil W · 8 Nov 2006 at 10:27

Gibbo said:
Hi there

£250 each on the rear and £260 each on the front. Not too bad but I do get trade and cash price on tyres.

Blimey, quite a lot then. How frequently do they have to be changed?

Out of interest, what is the profile on them?

Gibbo · 8 Nov 2006 at 10:29

Phil W said:
Blimey, quite a lot then. How frequently do they have to be changed?

Out of interest, what is the profile on them?

Hi there

The rears are 275/45/20
The fronts are 275/40/20

At the moment car has 7000 miles, rears have approx 4-5mm left. I suspect by 10-12k they will be down to 2-3mm and due for replacement. The fronts have hardly warn.

They seem good wearing, not too soft and good all round dry/wet grip tyre.

Phil W · 8 Nov 2006 at 10:33

Gibbo said:
They seem good wearing, not too soft and good all round dry/wet grip tyre.

20"

thebrasso · 8 Nov 2006 at 10:36

Kudos to you for doing the work yourself, awesome car. I've seen you a couple of times coming up City Road going to OCUK. Your car definitely turns heads

I wish I could make it to the RR but theres just no way I could get that day off work

siztenboots · 8 Nov 2006 at 10:40

Phil W said:
What are the wear rates & replacement costs on consumables such as underpants?

I'm classing them as consumables as i'm assuming they don't last all that long when giving it stick?

Fixed for you

iPWN · 8 Nov 2006 at 11:10

very nice Gibbo. How has that affected the insurance though? respect for doing it yourself too

Firestar_3x · 8 Nov 2006 at 11:18

thebrasso said:
Kudos to you for doing the work yourself, awesome car. I've seen you a couple of times coming up City Road going to OCUK. Your car definitely turns heads

I wish I could make it to the RR but theres just no way I could get that day off work

How come, not seen you since the Silverstone camping

Gibbo · 8 Nov 2006 at 11:32

iPWN said:
very nice Gibbo. How has that affected the insurance though? respect for doing it yourself too

Hi there

An extra £60 per year on my premium.

penski · 8 Nov 2006 at 11:36

rayb74 said:
How did you lower the compression Gibbo? Or do cars with large capacitys not need to worry?

You don't need to lower the static compression ratio with a positive displacement supercharger.

There's a lot of crap talked about supercharging by people who think that they provide boost...or indeed that 'boost' is a good thing.

A guy I know is going to be running 9psi of pressure at 10.2:1 static CR on a 1600cc four-pot. He's aiming for 230bhp.

What you are looking to do is identify at which point in the rev range the engine is operating at closest to 120% of volumetric efficiency.

You then use the blower manufacturer's pressure maps to ascertain what pulley ratio you require for your desired pressure at your desired rpm.

6-7psi will mean that you don't have to cool the charge but most modern engines should be able to take 9psi with a chargecooler (£75 for a pair of Jag ones off t'bay. Use one, flog one.) but splonk £1,500 on a good crank, rods and pistons and look at 12psi

.

What you are looking to achieve is 120% VE over as much of the rev range as possible. In doing this, you will flatten the torque 'curve' and raise it (usually in the region of 25-30%), thus increasing the area under the curve (which is the most important part).

Raising the VE makes the engine more efficient and easier to drive.

That's a very basic breakdown of the method behind it but you can safely run a low-pressure positive displacement blower on a high static CR.

*n

Almeda · 8 Nov 2006 at 11:40

Oh penski, you're like a minature Buddah covered in hair

Simon · 8 Nov 2006 at 11:54

Very nice. Gonna pull like a train!

Been a group buy on these on S2000 forums, look at the size of them http://i53.photobucket.com/albums/g54/Bibbs_1977/DSCN0938.jpg

Penski, that method is no different to a turbo, both mainly rely on the compressor map to match the compressor to the engine/user requirements. You can run turbos on high static CR engines. You going to struggle to find anything near to 120% VE on a NA engine too.

New superchargers are being developed with gearboxs to allow much more boost low down

Gibbo · 8 Nov 2006 at 11:57

Simon said:
Very nice. Gonna pull like a train!

Been a group buy on these on S2000 forums, look at the size of them http://i53.photobucket.com/albums/g54/Bibbs_1977/DSCN0938.jpg

Penski, that method is no different to a turbo, both mainly rely on the compressor map to match the compressor to the engine/user requirements. You can run turbos on high static CR engines. You going to struggle to find anything near to 120% VE on a NA engine too.

New superchargers are being developed with gearboxs to allow much more boost low down

The charger is kicking in full boost on mine around the 2000ish area I think or certainly beginning to build nicely, hence my traction issues in 2nd. If I give it part throttle and then nail it the back-end just digs in and the force pushing you back is just amazing, never felt anything like it.

D4VE · 8 Nov 2006 at 11:59

Man it sounds so good, I want one

Any pics of the car with the 20s on?

Gibbo · 8 Nov 2006 at 12:30

D4VE said:
Man it sounds so good, I want one

Any pics of the car with the 20s on?

Hi m8

Its always had 20's on, they are standard fit on Saleen Mustangs.

Check the OcUK Motors website for pics.