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Project Supracharger


David P

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That manifold is a piece of junk, the flange isn't near thick enough, it also needs dividing into sections longitudinally to minimize expansion growth across the studs, and it needs the type of washers Nissan use on RB25 turbo engine exhaust manifolds to allow good clamping and still allow some growth movement. You MUST only use a multi shim gasket, anything single layer will fail. I think you ARE using a MLS gasket type though? It really needs replacing by something with a flexi section in each runner, or slip joints. Straight six manifolds are a nightmare due to the head flange length involved. Once they crack it's game over, the cracks are carbon contaminated and it's all but impossible to weld without contamination of the filler. Plus the heat input at an already weakened area, weakens it further. It really needs making out of Inconel to be 100% durable. Which is going to be pricey! Plus I bet it's a PITA to take off and put back... :(

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I used a used stock gasket and it was a PITA/Back, for 5 days of as much leaning over as I could do that I shouldn't have done in that time. :shrug:

 

I've had a look/feel as best I can and there's a good chance that the rear nut has bound onto the un-threaded centre of the stud before clamping the flange that's a nodger thinner at that end from the previous planing and curling up a bit after the recent repair.

 

I'll have to take the charger off to get at it and the spare studs I have are at Bob's Workshop, I daren't attempt the job without one, so it'll have to wait until I can get access and retrieve one.

 

I hope I can fix it without winding my back up too much because a new one would leave me without an arm and a leg too. :think:

 

Here's a little job that you may approve of, I've fitted the Pro Alloy water/meth tank. :)

 

Other than the cap, it's a flush fit under the carpet and lowers/centres 10kg, but I think the twin ERL pumps may have to be mounted underneath?

 

It's not a brilliant fit for a bespoke item, but the self centring spare wheel clamp :think: clamps it firmly into place without need of any fixings, when things have settled in a bit I'll drill and fix it then.

 

I've changed the slotted OE tool-kit foam-piece, for the more useful tool-wrap divot version and trimmed the OE cover so it actually fits.

 

attachment.php?attachmentid=168625&d=1367423079

 

attachment.php?attachmentid=168626&d=1367423079

 

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Pro Alloy tank 001-001.JPG

Pro Alloy tank 002.JPG

Pro Alloy tank 003.JPG

Edited by David P (see edit history)
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That looks good david! If I get time I'll take a couple of studs from a scrap head and post them to you FOC. I am really pulled out with my father in law being very ill, so don't expect them tomorrow ;)

 

That's kind of you Chris and would save me waiting for the cows to lay down and a 30+ mile round trip too.

 

Thank you very much. :thumbs:

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That looks the nuts. I want a tank like that one! bet your well pleased. Well I assume by having 3 photos you must be happy with it.

 

I bought it secondhand from a member on here, but I believe they're still available new if you want to sell one of your kidneys to buy one.

 

It's the best tank available for the job.

Edited by David P (see edit history)
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Since evicting the TPS circuit Gremlins, recalibrating the ECU's, running 2.5" exhaust-gasket restrictors and adding octane-booster to the fuel, either/and/or/all have contrived to annul the peak-torque pre-ignition. :)

 

Today I needed to test fit the 3.8" pulley with 2 different length belts and fitted a new idler-bearing whilst I was at it, and after going with the 2535 have given it two second-gear test-pulls.

 

AFR reads a steady 12 and no issue with pre-ignition, boost comes in a little sooner and is up to around 12.5lbs, yet fades back to 11.5lbs as the revs rise.

 

There's no smell of belt-slip, but have adjusted the spring-tensioner from min to max for now, maybe it's escaping back up the water meth jets, or the flow through the 72mm t.b. is beginning to max out?

 

We'll all know soon enough. :shrug:

 

It's amazing how much 'perkier' it is to drive, if it continues to behave I'll leave it on.

 

attachment.php?attachmentid=168642&d=1367429666

3.8 pulley 008.JPG

Edited by David P (see edit history)
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How hot is the compressor housing getting now with that pulley David? I know with previous tinkering on my v8's with the same charger if I went too small with the pulley I passed the point at higher revs where the compressor remained at a stable temp

 

Your builds looking pretty awesome mate

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Thank you for the kind words Pulley, the Project's coming together now, in a random as I can get at it order. :)

 

All I know re charger and/or induction temps is that when asked, Dan said he was surprised how low they were, :think: and that was with the charge-cooler

turned off. :shrug:

 

It's only spinning up to 12k at the mo and 14k if it'll run a 3.2", Eaton run them up to 14k with some stock installations so it should be happy enough.

 

When it's next mapped I'll ask for a display of boost and charge temp on the graph.

Edited by David P (see edit history)
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Here's a couple for the thinkers amongst you. :think:

 

 

For some time now, I've been hearing a ping at low revs that sounds just like pre-ignition on one cylinder?

 

It would appear that the "ping" is because of a slight blow on no. 6, causing the multi-layer gasket to expand and ping onto the steel manifold flange.

 

Below is a pic of the exhaust gasket recently removed that shows the blow and is misshapen and worn from the movement.

 

 

attachment.php?attachmentid=168799&d=1367702149

 

 

Here's the other.

 

Since fitting a 3.8" supercharger pulley, boost has been mysteriously tailing off in the upper rev range?

 

I've thought this one through and realised that I have the bypass valve actuator vacuum pipe plumbed pre supercharger and it should be post. :blush:

 

It has been working perfectly well until now the suck is beginning to put a demand on the intake aperture which is causing a pre-charger partial pressure drop, which is causing the bypass valve to open a little and recirculate some of the boost.

gasket 015.JPG

Edited by David P (see edit history)
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I'm working my way through the shopping and leaning-over job-lists, :) in dread of the antipofootwelectrickergarmi. :(

 

 

With re-plumbed bypass-valve actuator-vacuum. :innocent:

 

I've given it one second-gear blip/pull to 5.5k, boost now comes with less encouragement from the pedal and holds pressure, 3.8cracklepopbang. :D

 

I'll refit the 4" pulley. :)

Edited by David P (see edit history)
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3.8" pulley off, 4" pulley back on and it's running sweetly again, :) 3.2" and 3.4" pulleys ordered, :think: it's been a pulley kind of day.

 

I've found the cold start rattle Gremlin, the swirl pot was tapping the bonnet and have ground off a few mm of fibreglass to clear.

 

The 245 45 18's on 15mm lowered suspension are tight as tight can be and have adjusted a couple of arch seams and mudguard mountings to clear the tyres when on full lock and full compression.

 

Been out for a test trundle, more torque at the bottom end and with torque-convertor lock set at 2k combine to make it a more willing horse, so to celebrate I Stuka'd a Scooby. :innocent:

Edited by David P (see edit history)
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Today I took a closer look at something I noticed yesterday, :think: after it was back together of course. :shrug:

 

Discovered that DBA 5000 front discs are not completely compatible with U.K. spec shims and pads.

 

I've clipped off the anti-squeal shim bottom locating tags, the pins locate them fine without.

 

Also cleaned the casting marks off the pad plate, but will need to take a mm or 3 off with a flappy wheel for them to clear as the pad wears down.

 

Pics tell the tale.

 

Wear on disc nuts

 

attachment.php?attachmentid=169026&d=1368039314

 

Catching on anti-squeal tag

 

attachment.php?attachmentid=169027&d=1368039314

 

Now clipping one and soon the other

 

attachment.php?attachmentid=169028&d=1368039314

 

Tags removed

 

attachment.php?attachmentid=169030&d=1368039314

 

Casting rough removed with file

 

attachment.php?attachmentid=169029&d=1368039314

 

The back edge of the pad plate is going to need reprofiling to clear as the pads wear

 

attachment.php?attachmentid=169031&d=1368039331

brakes 007.JPG

brakes 008.JPG

brakes 010.JPG

brakes 014.JPG

brakes 015.JPG

brakes 018.JPG

Edited by David P (see edit history)
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I'm pleased that a fondle of my flappers made up for the oil spill in the workshop. :blush:

 

I hope Littler soon gets over his sideways supercharged experience. ;)

 

That's a couple of underneath jobs jobbed and the pulleys will be here in a few days too, the light at the end of the tunnel is getting closer. :)

Edited by David P (see edit history)
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Bad weather has grounded any tinkering much for the next week or so, :think: so doodling to scratch the itch.

 

Finalising appearance of the front, I'm refitting the J spec plate backing with the current small plate, removing the badge and considering fitting a Cooper S scoop at the centre to let some more wind through the willows of all the radiators in there.

 

Could someone please photoshop the scoop onto the bumper, (without the mini badge please :rolleyes:) blended in and lined up with bottom of headlamps would be the plan.

 

The angles of the pics are similar, yet the scoop will need reducing in size.

 

Thanks in anticipation. :)

 

(Pic courtesy of Shane)

 

attachment.php?attachmentid=169419&d=1368486347

 

attachment.php?attachmentid=169420&d=1368486526

meet pic.jpg

mini scoop.jpg

Edited by David P (see edit history)
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Today I received a reply from DBA, they inform me that the discs were designed using O.E. components and it's an aftermarket pad issue.

 

They have redesigned the disc bell to accommodate Chris Wilson's pads, anodised them black and a new pair are winging their way from Australia to me with their compliments. :)

 

First Class Service. :thumbs:

 

The new supercharger pulleys have arrived from CDF too. :)

 

I sent the 3.8" to them only last Thursday, more First Class Service. :thumbs:

 

I know it can pull the 3.8" and we'll soon find out how low it can go. :think:

 

Top 3.8", left 3.4" and right 3.2".

 

attachment.php?attachmentid=169459&d=1368623633

pulleys 003.JPG

Edited by David P (see edit history)
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