Tweety to get a supercharger

[ea81slush]

I've purchased a SC12 Toyota supercharger. Dont know if many SC's are common in the USA but will post progress as it happens over the next few months.



Some specs.

Toyota SC12 revs to 12,000rpm max 14,000 rpm for short periods
Will be seeking 5-8psi.
Carbie will be a Dellorto 40mm side draught
Will be a draw through set up.
Hoping for 25% more HP and 30% more torque

Received my SC12 Toyota supercharger today in the mail.

Impressed. It appears internally to be very sound. No slop at all in the bearings. fair bit of dust on the rotors so am wondering what to clean them with as dont want to take any teflon off. ???



and the end casing was clean ready for some new oil. 2x (100ml) Holden supercharger oil will be ample.



Dellorto carbie will be here soon.

[chromedome1964]

Are you building your own intake, or do scoobies have one available?

[ea81slush]

I will be fabricating both manifolds. Subies in this ea81 here in oz had a turbo and twin carb set ups but nothing like this.

The adapter plate that sits on the intake to mount the weber 32/36 there currently might be utilised for the manifold mount. Being lloy might search for a couple of 2 inch 90 degree alloy bends then a plate on the exit of the SC.

I'm in touch with guy called Joel who put one on a VW beetle here in oz. very interesting reading and images of the set up. I'll be copying most of his ideas.

I've worked out on the calculations that a 1:1 pulley set up will give 5-6 psi. As the draw through design cant have the clutch pulley operational I'm about to seek a fixed pulley unit. The next step in this process.

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[chromedome1964]

Wow, that's a sweet setup on that bug. Good luck with your project and keep us posted!!!

[ea81slush]

Blow off valves.

For those unaware these valves allow for excess pressure in a manifold to release such pressure either into the atmosphere or better still plumbed back into the air cleaner area.

Beware! cheap chinese copies have flooed the market. Some fail and you can end up with peices inside your engine.

I went the middle road with price for $167.50 (AUD) for a turbosmart valve with a flange to mount it on the manifold between the SC and the intake.

TURBOSMART PLUMB BACK KOMPACT BLOW OFF VALVE MAZDA SUBA | eBay



My next action is the pulleys. I've worked it that like the VW supercharger thread by Joel that 1:1 is about right for 5-6psi with max about 8psi. This will keep the engine cool and wont risk internal damage through high stress. The SC12 came with a clutch type pulley which you cannot use with a draw through system. You could fix it with power to it but better to find a fixed pulley. Thats the task. And to match it up size wise to the crank pulley.

Toyota's had a 150mm (6") crank pulley and 4" charger pulley making bout 10psi.

Too much for what I want to do.

My crank pulley has a 6" pulley and a 2 and a half inch pulley that isnt being used.

But neither are the right size so got a 4" crank pulley lying abotu so hope to find a suitable pulley at a junk yard.

[ea81slush]

Grabbed some alloy plate today and tube and made my first sC outlet.

[ea81slush]

Amazing what you find in a shed when you're looking.

This had to come off my ea81 when I stripped the external stuff off it.

And the bearing is in good nick. Likely it came from a past A/C belt system. I'll get my engineer to turn it so it can rest against the back flat of the V-belt.

Make a good idler pulley for the supercharger. I'll hinge it and make a slot adjuster bar.

What I'm planning now is have a good look at pulley sizes I have on the crank when I get my trike back from the engineer this week and settle on a pulley size for the SC. then take it to a pulley joint to find out if I can get a pulley fitted that can be interchangable. Dont want complications alter down the track because I'm reaching 10-12 psi and not the desired 5-6 psi

[Peter35]

Smokey, you cant use a turbo because of not having a tuned exhaust, i believe.
Do you think the SC will have the same results as a turbo, or more or less power/ torque?

[ea81slush]

Hi Pete. I dont want to dismantle/modify the exhaust to drive a turbo. Also turbos are better at high revs and more likely to need decompression of the combustion chambers.

Its widely accepted now that supercharging especially with the Toyota roots units SC12 and the longer SC14 is the cheapest bang for buck. (SC12 for 1-2 litres SC14 for 2-3 litres) And the easiest installation being the draw through set up because you dont have to pressurise your carbie among other annoying issues.

Supercharging at around 5psi will make the trike/car outstanding in terms of performance compared to stock. Around 25% more power and 30% more torque and the torque will come in at about 20% lower revs. But the biggest advantages are:

That it comes in when under load or need. So you can idle around at a casual throttle and not have it roaring away. Imagine cruising along the freeway (sorry interstate!) and you want to overtake- bang it comes in. Towing? excellent idea too.

Economy doesnt effect it much at all.

Climbing hills will be a breeze and not loping along with throttle jammed open.

for these reasons it a no brainer.

Likely all up cost less than $1000.

Read this Pete.

its a vW using the same set up as I'm doing.

Aussievee dubbers - Tech Talk - Blowing The Bug - Powered by GaiaBB

[Peter35]

a real interesting article, Smokey.
l think i might look at this some more before looking at swapping motor over to subaru. worse comes to worse could fit the subie motor and fit sc to it as well.

[ea81slush]

Peter, as you can see the Sc on a vW engine is very feasible and easy. Then again a SC12 or SC14 on a EJ subaru engine works even better because they have a EMU that, I think, alters the fuel to suit the air boost automically. No hassles with jets.


This is the Datsun 1600-2L intake manifold I have purchased on ebay.

I'll cut off one half to use my delorto carbie on the SC. and have one half left over. Note how the tubes go towards each other to get up close which I need so it is directd into the square gap intake of the SC12.

[Peter35]

lts looking good

[ea81slush]

Busy day today on the project. Cut some slots to make the opening more sqaure like for the exit of the SC. and my Dellorto carb + a spare carb came in the mail today. Then after cutting out the 3mm steel plate I tack welded the pipe to it. I'll get my engineer to weld it fully.





and can anyone tell me what this hole is for and what I do with it?



and in this pic there is the throttle on the left. I assume the level on the right hand side of the picture is the choke???

[chromedome1964]

The hole you asked about is a vent and should be left open to air. Most people just trim the gasket away from it. You are correct, the linkage on the left side is throttle and right is choke.

[ea81slush]

thanks chromedome1964

Third time lucky or was it fourth try? to make a manifold?

Anyway got it this time.





the 4mm gal pipe was too heavy. 1.6mm steel pipe from where I got my exhausts done. Tested my welding as it was easy to blow holes through it. but got there in the end.

[ea81slush]

Got the manifold and cut it in two.

Didnt count on it having a designed bend in it. either I lean the Sc over a little or make the 5mm-10mm adapter plate from the manifold to the sc on an angle. Think the former will be easier.

Now I'll start making templates for the plates.

[Peter35]

looking real trick Smokey.

[Peter35]

Smokey, whats happened to the other photos or did you delete them?

[ea81slush]

I'll go back and edit and reinsert. I moved them on photobucket to another album and didnt know it would do this.

Today was interesting.

Most SC12's and sC14's come with a clutched pulley. add 12 volts to the two leads and you have lock on. But they can slip and besides you cannot use a clutch pulley on a draw through set up. After all, fuel and air mix cant get through the vanes in the sC if the lobes arent turning. Different with a blow through because those systems have a bypass when you turn off the clutched pulley.

I had planned to use a v-belt set up. Thats because I have a triple v-belt crank pulley already on the engine. But my engineer rang today to tell me it would be quite difficult to fit a fixed v-pulley in lieu of the clutched 5 ribbed one on the SC. But quite easy to fix the clutched pulley solid. So be it. means a 5 ribbed belt is going to be fitted. so off to the wreckers where I found 1/ a 5 ribbed 135mm pulley for the crank and 2/ a ribbed tensioner pulley and a flat pulley interchangeable. Which do I use- flat or ribbed tensioner?

The flat pulley runs on the back of the ribbed belt and tensions up to make more footprint on the belt around the crank and SC pulleys. It also makes the belt bend opposite to how it travels around the other pulleys possibly causing more wear.. The ribbed pulley tugs at the belt = less belt on the pulleys. but it allows the belt to onlt bend the one way.???? ideas/opinions?

Found a 5 ribbed pulley for the crank. I have a standard single crank pulley. My engineer is welding/fixing the ribbed pulley to this. But it is 135mm diameter. The Sc pulley is 115mm. meaning not 1 to 1, the figure I sought. this means more boost than anticipated. maybe 8psi. vrooooom!!!

Might start the install next week. But we are going on a 3 day holiday soon so a bit of a delay.

[chromedome1964]

Smokey, go with the flat tension pulley on the belt. Superchargers require a lot of horses to turn and you will need the extra contact with the other two pulleys. Ford has done this for years on their serpentine systems driving the water pump on the back of the belt. There is no increase in belt wear.