Indeed! I dont suppose you could tell us once and for all if that was the 300 cc or the 600 cc version of the Subi supercharger? (there is a little green sticker on em with that info) I have been looking around and can only find 300 cc versions which will need to be overdriven pretty heavily to be useful.

ill have a look and let you know.

i had a good look but cant find any green sticker, might have been removed when cleaned or something, the best i can tell you is that it is an AISIN supercharger. the unit is fairly over run though (from memory wally said it was 2.5 times), 7 psi at 7000rpm but seems to run out of puff, more down low power which is typical of a SC i suppose.

Its a centrifugal unit off a Subaru 990 cc.

Need more info look at the rech section. There is a detailed section about wallys wagon with pictures

http://datsun1200.com/modules/nsections/index.php?op=listarticles&secid=7

Hmmm.. but HERE it's pointed out it's off a 660cc motor and displaced 300cc...

2QK4U-

We can sort this out easily enough... Wally said the crank pulley was 135mm and he was getting 7psi.

to get that out of the AISIN AMR300 on an A14, the sc pulley would have to be around 40mm and the blower would be spinning at....... wait for it...... 24,000 rpm

no wonder its running out of puff!!!!

If the pulley any bigger than that, you should not be seeing 7 psi (or its the AMR500 blower).

im not mathematically inclined... but yeah with that sort of RPM from the supercharger it would make the little fan a heat gun! with the draw through setup though the fuel gets sucked down the carby really fast so the fuel gets extremely cold - there is actually water dripping of the pipe at idle from the condensation! so intake isnt actuall that bad. so what SC do you think it has?

Quote:

Dan,
If you have the time can you explain this, I dont understand

based on a post by feral that I cant find at the moment...

7psi + 14.7psi/14.7 = boost ratio

x by 1/2 engine displacement (i.e 2 cyl fire every rev) this is the volume required per rev

volume required/blower displacement =pulley ratio

7000rpm x pulley ratio = blower speed

so to produce 7 psi at 7000rpm, the pulley ratio is minimum of 3.444:1 and the blower speed is a minimum of 24,111rpm

if it is an AMR500 the ratio would be 2.067:1 minimum and the blower would be spinning at a minimum of 14,467 rpm

so 2QUK4U- if you can measure the sc pulley we can work out which one it is. if the ratio is 2.5:1 I spose it has to be the AMR500 (or an AMR600 if that exists) cos the 300 would not flow enough at that ratio

Im onto it, ill measure it on the weekend - earliest time ill see the car.

why the 14.7 psi??

14.7 psi is the pressure of earth's atmosphere ... a natural phenonenom.

oh ok wow thats interesting.

ok measurements -
blower pulley - 69mm
crank pulley - 136mm.
according to dad (very machanically experienced and mathematically enclined) he thinks the blower is at a ratio of 3.5:1 so at 7000rpm he says the blower will spin at 24,500rpm. i havnt shown him this thread so you both must be correct.

2Qk4U-

136mm to 69 makes the ratio 1.95:1 so the blower must be larger than 300cc to make 7psi boost. I suspect its an AMR500. I have not been able to find one of these.

on an aside- Rogue said he used the AMR300 and a smaller jet in the carby, which is consistent with this being the larger blower.

Edits:

Rogue's comments on this setup

Useful info on these blowers (chatroom)

Because the supercharger runs out of puff and the torque doesnt pull all that hard from about 5500rpm onwards, would it be feasable to get the cam worked to try compensate and produce a more consistant torque curve? i like to rev it too about 7000rpm, would any of you please explain to me how the cam concept (lash duration, how much and how i work out how much to get the cam grinded ect) works and if im on the right track? - The engine has a standard spec cam in it now, would that be why it has more torque down low? if i want more top end torque will i sacrifice down low torque? B120dat you got me thinking...........

You will almost certainly get more with a specific cam grind, but I cannot educate on exactly what.

My ute has a mystery cam, (the builder couldnt remember but reckoned it was probaby a 30/70 or 35/75 cos that's what he usually uses for street builds) So if I ever get my act together enough to strap the SC14 on, I'll let you know how it goes!!
It has a pretty lumpy idle and low static compression so I am a bit worried that it will not be suited to the blower.

2QK4U-

I had a look at Marks turbo ute yesterday

efi turbo

He is running a turbo cam in it which is 30/65 on the inlet and 70/30 on the exhaust. It goes pretty damn well, but I dont think It would pull hard to 7k (I only took it to 5500)