Project Supracharger

Recycling the cam belt tensioner wheel from jig engine and a piece of steel cut from a broken industrial component.

I have fitted a stud to the billet, cut a brace of fillets from the offcuts, welded the pieces together and carved the mounting to fit between the cam gears.

The idler bearing/bracket fits like it was made for the job.

This will reduce belt-whip and increases wrap on supercharger pulley, with the option of fitting a larger wheel if more wrap is required.

With the guard modified and fitted, it looks as though it belongs there.

I declare this job jobbed, that's one more off the list.

Machined a flat surface to centre of pulley wheel, made an adaptor and recycled a steel Supra belt tensioner pulley to form the beginnings of a power steering pump support bearing/bracket.

The main pieces of the pulley support bracket are formed and ready for assembly but the adaptor I made is slightly on the wonk.

It was my first go on a lathe and haven't worked out yet how it went wrong, so have asked a pal to use it as a pattern and knock me up a straight version.

looking really good. what sort of power output you expecting/hoping for?

That tensioner is a nice bit of work, I like your creative thinking there

Sorry to ask a dumb question, but why is a support braket needed for the PAS pulley? Is it due to the extra stress the SC could put on the belt system?

looking really good. what sort of power output you expecting/hoping for?

Thank you for the compliment.

Here's the post you missed.

6.78” crank pulley / 4.2" supercharger pulley x M112 = 13.56psi (0.93 bar) 711 cfm (20,147 lpm) engine 6,800rpm s.c. 10,977rpm

dynamic compression 16.86:1 (figures allow for valve overlap and @ 95% ve)

 

Along with the water/meth and HHO, I think it could be possible to scrape into the exclusive 500 club.

That tensioner is a nice bit of work, I like your creative thinking there

 

Sorry to ask a dumb question, but why is a support braket needed for the PAS pulley? Is it due to the extra stress the SC could put on the belt system?

Simple, strong and true. I am pleased with the outcome.

The power steering pump wasn't designed to have 50 bhp of supercharger pull loaded on it, so I'm giving it an additional bearing to support the pulley in double shear.

I am asking a lot of the 6-rib belt system that was designed for less demanding accessories, so I am giving it it's best chance.

Tomorrow I plan to fit the new idler pulley, supercharger bracket/throttle-body assembly and air filter, these can then stay on the car.

This will allow me to check belt length with the larger ATI crank pulley and progress to fabricate a cold-air filter box.

I am working on elements for several of the countdown list jobs.

The supercharger bracket, throttle body, induction/air filter and additional belt tensioner are on the car engine to stay.

Fitting the bracket required removal of the N/A throttle body, distributor, alarm and thermostat housing, yet now it's in, all is well for clearance and function.

The Supercharger throttle body is fixed at WOT and the N/A induction is plumbed through it keeping the car operational.

Glad to see some bits making into the cars engine bay now.The idler pulley /bracket is clever.

Glad to see some bits making into the cars engine bay now.The idler pulley /bracket is clever.

There are lots of little hose and loom tails creeping into there, I have the job 'surrounded' and working towards being as close as possible to a plug & play installation when the big day comes.

It is satisfying to install a few of the components into their new homes, which even though made to my own guessmeasury specifications, it remains almost a surprise to find that first time on the car they actually all fit and function without 'issues'.

The new adaptor for the power steering pulley is made, but I need to find another OE steel pulley.

I don't want to use the alloy one I have, as I plan to return to steel for maximum strength, of which I have two, however, one is bent and the other was from a burnt out Supra and is very rusty.

This pulley/bracket needs to be even cleverer.

im sure i have a spare power steering pulley in the shed ,bare with me i will go check.

Got it pm me your address and i will send it tomorrow mate.

Cheers for that Barney.

With that job jobbed, the countdown list will go to DEFCON 5.

Looking good David, glad you went for a double shear bearing for the PAS pump, they are a bit delicate even when run as intended If you were to "productionise" this would it not be easier to have a dedicated crank pulley for the SC and a dedicated belt, forward of the auxiliary belt? The SC would have to be further forward of course.

The belt and pulleys are an unknown quantity and the 'Achilles heel' of the project.

Should this element of the build fail, I will need to upgrade to an 8-rib and maybe also change to dedicated pulleys.

First I am beefing up the 6-rib system to give it it's best chance, and see what happens?

Here's a pic of the Hecklertronics that operates the gear and lock-up display.

This gizmo would function with any ECU on N/A or T.T. Supra auto trans.

Just a quick one ,dont forget to put the bolt back in the end of the charger snout.

What bolt.

What bolt.

the one that goes in the end to hold the pulley /hub on,should be a 10mm bolt with a washer.

There's no bolt in the end of this one, it's just an interference fit.

Originally there was a plastic button clipped into the end, yet that died some time ago.

Another full days tinkering, yet not a lot to show for it.

The 4" to 3" elbow has been shortened one way and lengthened the other, it is a bit of a clip-fest, but the cold-air box will be easier to fabricate over the straight panels now beneath the filter.

I have made some minor modifications to the Lexus throttle body and the Supra throttle position sensor is now set up to read as a stock Supra t.b. and refitted with new gasket.

The TPS is now insulated and the wires are routed into the loom across to close to the N/A TPS wires.

The rear section of induction insulation is fitted and the HHO feed hose is connected and for now, bundled up next to brake master cylinder.

Barney's pulley has arrived, so I can get on with the power steering pump support bearing.

I see,

Using the aluminium and door seal found at the scrapyard, I knocked-up a cold-air box.

It is secured onto 3 OE 6MT fixings and the alugarmi fitted perfectly first time.

There will be a little more work routing the throttle and cruise cables through it when I have some, but think that job is jobbed enough to take it off the list and declare DEFCON 5.

I was hoping to go to DEFCON 4 today, but it turns out that the Mk2 adaptor for the p.s. pump pulley is on the wonk, it's not as wonky as the one I made, but wonky it is.

After I have found someone who can make a straight adaptor allowing me to complete the support bearing, I can at last temporarily bolt on the supercharger and spin it up to check the belt stands up to it.

To do this I need to prune 1/2" off the front of the N/A t.b. to get the charger in, yet the spare I had was carved up for components to make the supercharger ICV.

I would sooner not shorten the one I have fitted because a lot of effort went into taper reaming and polishing it.

Does anyone have an N/A t.b. gathering dust?