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Project Supracharger


David P

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I've had two afternoon windows in the weather conditions and have managed a couple stints in a cosy corner out of the wind.

 

No pics from Thursdays tinkering, I was too busy racing the sunshine.

 

Supercharger off and re-shimmed mountings and modified the insulation on induction elbow to clear bulkhead, inspected supercharger and rebuilt.

 

There are a few left-hand only awkward bits, which were a lot more awkward with my dodgy digit. :shrug:

 

All is well. :thumbs:

 

 

 

Today I had the charge-cooler off and on again, fitting new plugs, rocker off to "repair" oil-leak and fitted another hose-tail into boost side of manifold.

 

All back together again as the sun went below the tree line on both occasions. :cool:

 

 

 

Offagin.

 

attachment.php?attachmentid=161650&d=1354997891

 

Shown 6, 2, 3, 5, 4, 1. :think:

 

6 & 5 rusty, a souvenir off the Mad Max days, :shrug: 4 & 3 oily, from leaky rocker-cover :blush: and 2 & 1 were just right. :slap:

 

But baby bears bed are the tips that all look just fine. :)

 

attachment.php?attachmentid=161661&d=1355003760

 

The RTV had almost no adhesion to the Liquid metal or the casting and lifted off easily except where I had scratched a line on the crack, so after three good scrubs with solvent degreaser, rinsed off with boiling water, then scrubbed 3 times in methanol, I gave it some scratches to think about and a super-thick mega-blathering with RTV.

 

attachment.php?attachmentid=161652&d=1354997891

 

I was underwhelmed by the almost complete lack of adhesion of previous RTV repair, yet had no polythene product at hand to try, so had to use RTV again, this'll have to do for now. :shrug:

 

attachment.php?attachmentid=161653&d=1354997891

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offagin 006-001.JPG

Edited by David P (see edit history)
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It's amazing how awkward everything has become, wonky finger, wonky weather, wonky workshop access and wonky deliveries.

 

The modified valve-body for the transmission won't be here in time to fit before the remap.

 

So that just leaves bracket final tinkering and hope that the new supercharger pulley gets here in time.

Edited by David P (see edit history)
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Frost tested :cold: during final-fitting, the Sky Hook Bracket lives. :)

 

To align the pulley I shimmed the idler bearing to be flush with face of supercharger pulley and with a 'special service tool' across the faces, clamped it where it needed to be, then shimmed between centre-fixing and supercharger bracket with a thin washer and nipped the bolts up where it sat.

 

attachment.php?attachmentid=161851&d=1355339996

 

attachment.php?attachmentid=161852&d=1355339996

 

I'm test-driving the new set-up before destruction testing on the dyno. :shrug:

 

Currently running reliably with a shoulder-less supercharger-pulley and an unforgiving Gates belt, will change to new pulley and Gatorback belt as they arrive.

 

attachment.php?attachmentid=161853&d=1355339996

 

It looks as though the previous configuration was not that far short, a little slippage yet could boost to 11.5 lbs. (charge-cooler on)

 

With new belt-configuration there's no slip and it boosts-faster to 11.5 lbs. (charge-cooler on)

 

Without the charge-cooler there would be around 1 lb more.

 

I'd reckoned the boost would be around 15 psi with this pulley, maybe it's a sign of good gas flow and cool charge?

 

Pressure or not, it'll be pumping 747cfm @ 6,800rpm. :)

 

The new pulley didn't arrive today, so I've swapped tomorrow's remap to Friday, the Gatorbacks then get an extra day to turn up too? :shrug:

 

Driving home in the forecast blizzard will be enlightening? :think:

special tool 001.JPG

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special tool 003.JPG

Edited by David P (see edit history)
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The new 4" supercharger pulley with shoulders and cross-hatching has arrived, now fitted and tested, ready for tomorrows twirl. :)

 

 

attachment.php?attachmentid=161887&d=1355408812

 

 

 

Resolving belt-slip and discovering that boost is lower than expected, I'm tempted to use the 3.8" pulley for more psi, but curious to see what it'll do as it is.

 

I'll save the 3.8" until after I've fitted the modified valve-body into the transmission and after winter has passed. :shrug:

 

The valve-body is now seven-weeks behind schedule and presently held-up at L.A. airport.

 

The Gatorback belts are also overdue, not even a Robbing Tax Hoods ransom note yet. (Gates it will be then)

 

I haven't yet upgraded the (chair-leg) hose-tails on the swirl-pot. (They'll survive a bit longer)

 

The Water/meth system refit/upgrade is not completed. (Waiting delivery of final component)(and some better weather)

 

Three wheels on my wagon and in need of an interim remap to keep the project rolling along.

new pulley 001.JPG

Edited by David P (see edit history)
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CRACKED IT :yahoo:

 

Dan couldn't fault it, so that must be "Official". :)

 

Everything functioned perfectly. :friday:

 

Zero belt-slip under any provocation(s) and it's boosting a steady 11lbs from before 3k rpm?

 

Now the dog can see the rabbit, :) there's plenty of power for now and it's a pleasure to drive, even in the rain @ 5°C.

 

After I've tinkered with the transmission and the control(s) of it, then sorted out the water/meth system and the HHO system.

 

In the spring, I'll increase the boost a bit at a time up to 15psi. :think:

 

The Sky Hook Bracket proved sound and bhp still climbing @ 6,900rpm.

 

 

attachment.php?attachmentid=161926&d=1355492074

rollers 024.JPG

Edited by David P (see edit history)
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Is that the sort of power figure you were expecting ?

 

With 11lbs that looks fine, there's more power to be had, but after more needed works have been completed and warmer weather arrives.

 

I'm pleased to have evicted the final Gremlin, this part of the project is plain old nuts&bolts maintenance and improvements from here on. :)

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With 11lbs that looks fine, there's more power to be had, but after more needed works have been completed and warmer weather arrives.

 

I'm pleased to have evicted the final Gremlin, this part of the project is plain old nuts&bolts maintenance and improvements from here on. :)

 

Ahh, I read 21lbs of boost for some reason... had a migraine yesterday and brain is still a bit fuzzy. That's not a bad figure I guess for 11lbs, Stock TT territory.

Do you plan to go any higher than 15lbs eventually once you've enjoyed it for a while?

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Ahh, I read 21lbs of boost for some reason... had a migraine yesterday and brain is still a bit fuzzy. That's not a bad figure I guess for 11lbs, Stock TT territory.

Do you plan to go any higher than 15lbs eventually once you've enjoyed it for a while?

 

15lbs boost is as far as I'd go with a stock N/A lump and as far as I'd go with the charger.

 

Sorry - you're right. It was 500bhp and 600lb/ft with 40mpg. My question still stands though. I'm genuinely curious.

 

Reduce supercharger pulley-size increasing boost +4lbs, better exhaust system, larger (75mm) t.b. maybe, re-time cams on dyno, add water/meth and HHO will all help in the numbers game.

 

Watch this space. :)

 

After the job list a post or two before.

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It's been a long road but you are getting there now, being supercharged I thought the torque might be higher tbh, that's a long way down from even a stock TT.

 

I'm pleased that it's now working properly and my gadgets have all survived the death or glory testing(s) with flying colours. :)

 

The numbers don't tie up for me either, I had expected more torque than bhp, are the values same for both graphs?

 

I'm curious to measure the crank and supercharger pulleys to confirm I'm using the correct figures to calculate supercharger rpm too.

Edited by David P (see edit history)
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I just renewed my membership to see that dyno chart, really :)

Great work!

I presume 320 is at the wheels, the dyno chart says wheel torque, so I guess this is wheel power?

and that dip before 3000rpm is due to the autobox not letting to go full throttle and downshifting?

David, what sort of psi are you seeing at 1500-2000rpm?

I wonder if having so much boost of idle is killing the bearings :)

once again, I bow to your craftsmanship! you have fans in Poland ;)

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