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SP72

"We go again" ....

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So, with recent thoughts of selling the IB, and having something occasionally resembling a conscience, i've decided to investigate further by commissioning Neil Bainbridge of BS Motorsport to tear the engine down for a 3rd time in my ownership

For those who haven't followed my exploits, I had a top-end rebuild in 2008 (lets call it R1) which included an upgrade to 3.4, DC20 cams etc; this failed to cure a pretty severe cold start-up rattle and subsequent smells of metal on metal contact i had experienced before the rebuild.  

I then had a full rebuild undertaken in 2011 (R2).  The problems were still there after this and were compounded by several below expectation dyno runs, including a run on Neil's engine dyno which indicated a potential loss of 30bhp and similar torque.  I say 'potential', as it hadn't been on Neil's dyno before this, only chassis dynos.

Oil leaks have been pretty bad after R2 too, even after replacing the one piece oil return tubes which were the primary source of leaks, thanks to ill fitted o-rings.

Last week, Neil started the rebuild:

https://www.dropbox.com/sh/x2x6q8zcwizn0q4/AAD-Agz9QGYlIwwoAzTpfba-a?dl=0

Initial observations suggest:

a) the cam oil spray bar has been blocked (something i explicitly asked to be checked and was given the 'OK' during R2)

b) the refurbished rockers arms i supplied for R2 have suffered (the DC20 cams from R1 are fine) - most likely due to oil starvation, however potentially due to incorrect or insufficient hardening (TBC).  I had been running Motul 300v 5w/40 at the time of R2 and more latterly Millers Nanodrive 5w/40 - Neil sees no issues with either of these.

c) valve guides were not parallel (i'm quoting Neil), valves and valve stems needs further investigation

d) recent chain lash to be investigated further - tensioners to be re-checked (fitted during R1)

e) lots of misplaced sealant visible (see the orange splodges) - oil leaks were inevitable according to Neil 

More dismantling and measuring is in progress focusing on the top end; i'm hoping its now in the right hands (maybe that should be hand, as Neil only has one arm!)

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Interested to follow this Shirish

My engine previously needed a partial rebuild as a result of similar oil starvation caused by blocked spray bar and other poor reassembly shenanigans (thanks Zentrum!)

Think you're in good hands now

 

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So many hands puns - ouch. Looking forward to seeing what he can get from yours SP :signs118:

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Yes indeed - with the high quality synthetic oils i've been using since R2, i can't believe the spray bar has become blocked since 2011, but you never know.

Looking forward, R3 will add the following:

1) GT3 crank : the 2mm increase in stroke over the 3.2 crank and with the 98mm mahles, will create a 3540 cc engine

2) New custom Pauter rods

3) New GT3 oil pump 

4) New genuine rockers/shafts

5) New cams from William Knight / Rothsport - supposedly 'Singer' spec; TBC whether these stipulate ITBs or not

6) Straightcut intermediate shaft gears

7) Valve relief machined into current pistons (cams timed at 5mm overlap)

I'm reliably informed by William Knight, with headers and ITB's, its a 100 bhp/litre spec.  With SSI's and single plenum, i'd be lucky to break 300bhp / 250 torques (which i'm happy with, btw); William believes ITBs will be required, Neil is not convinced - either way it won't affect the core build and ITBs are considered as 'bolt on' items.

Neil's hoping to get the bottom end buttoned up in the next week or so - the Dropbox link will be updated by Neil as time permits.

 

 

 

So many hands puns - ouch. Looking forward to seeing what he can get from yours SP :signs118:

Yes, my bad - was an indirect compliment to his engineering skills, even with his disability.

Watching him at work is awe inspiring.

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NB is a legend - cracks me up. So what is the plan once the motor is done? PM me if you would prefer.

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Unsure at present JG - kinda lost interest in the IB over the past year or so, will see what happens post-rebuild.

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Good luck with this rebuild Shirish, 

Sounds like it will be an awesome engine.

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Cheers Steve, hoping to get my IB mojo back .

You need a road trip Shirish

Maybe after seeing the bill (and my psychiatrist )

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Shirish, I've been through this on my Alfa too, so I feel your pain. Currently on engine rebuild 3 due to poor work the first two times around. I feel like adding a rag to the tank and lighting it some days and I'm not sure when it's done whether to sell it or not.

I really hope it works out for you this time and it rekindles your love affair with the car.

Good luck.

 

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Cheers fella , I felt like that too on some days! Paying good money for stuff service really grates, doesn't it? Regardless, hoping 2017 will be a good year IB wise, otherwise it'll be up for sale.

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3rd time lucky on my 912e engine as well, though the costs of that would have been peanuts compared to this.

Glad you're sticking it out Shrish, you're at the right place.

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And by christy, what a spec! GT3 crank and 3.5!

Given you're all in I'd push the button on ITBs, they were great on my alfa (before it ran a bearing).

A 350hp Carrera 3.2! Much jealousy. I hope you have the brakes and suspension to match.

Edited by reddevil

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Cheers Nige

Chris - my hand may be forced into ITBs but will see. I'd love to fit some, but budget constraints do exist e.g. I wasn't planning for new rockers or oil pump, which would have covered the cost. Also, as mentioned, my SSIs will restrict matters to 300/250 ish. I think peak rpm will be around 6.5-7k rpm with SSIs, maybe 7500 with a bigger exhaust.

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Ding ding round 3! Lets hope its only a 3 round flight.

Good luck with the build, look forward to the updates.

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When we writing up a thread for number 4....................................:o

Don't worry, fingers crossed this will be the last and bees knees once completed.

Good luck and yes big road trip is a must

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Neil has advised cylinders 123 have 0.5mm base gaskets and 456 have 0.75mm - why would this be? 456 also have scars of valve contact which were there before R2 was undertaken.

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On ‎09‎/‎02‎/‎2017 at 10:50 PM, SP72 said:

a) the cam oil spray bar has been blocked (something i explicitly asked to be checked and was given the 'OK' during R2)

e) lots of misplaced sealant visible (see the orange splodges) - oil leaks were inevitable according to Neil 

Potential link? From what I understand, it is not just the issue of oil leaks with bad sealing practice, but also the problems stray residue causes.

Anyway, you are in good hands now and you should get the mega motor you deserve, its only money after all!

Just regard it as an investment in your families future, they can always cash it in and thank you  when you are long gone.  :eusa_boohoo:

Keep the IB faith Shirish, we are all wishing you your final long overdue motor success. :signs85:

Mark

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4 hours ago, SP72 said:

Neil has advised cylinders 123 have 0.5mm base gaskets and 456 have 0.75mm - why would this be? 456 also have scars of valve contact which were there before R2 was undertaken.

Possibly 3 of the heads needed machining more? Maybe the case wasn't perfect and the pistons are a fraction higher that side?

Sorry to hear of your troubles Shirish. It sounds like you're at the best place now though. Luckily, despite most other jobs on my car needing doing twice the engine and gearbox build was done very well by my specialist, touch wood, and they're the best parts of the par right now.

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Good points Mark. And thanks for the sentiment, means a lot.

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Cheers KS - Neil did say he's going to get the case onto his granite table which is where he checks case alignment. You'd think the CR would be reduced on that side by using a thicker gasket. Thanks, I'm hoping 3 really is the magic number :)

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From a glass half-full perspective Shirish it must give a sense of resolution to finally know what was causing your knock noises, power loss and oil leaks.

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1 hour ago, GaryH said:

From a glass half-full perspective Shirish it must give a sense of resolution to finally know what was causing your knock noises, power loss and oil leaks.

Yes indeed Gary, I'm actually still hoping more (easily fixable) issues will be found.

Neil thinks the oil starvation and rocker wear is the root cause, causing inconsistent cam timing.  Together with generally poor reassembly practice, which Neil is undoing piece by piece.  

Re progress , new oil pump has arrived and crankcase modified for clearance. Hoping the crank/rods/clutch/flywheel arrive soonish from the balancer peeps.

Wondering if I can get some ITBs via crowdfunding... :)

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Really pleased for you that this saga is finally getting resolved (even if it has cost $$$).

You'll have to get in the queue for the ITB crowd-funding behind my SC recommissioning KickStarter!  lol

Edited by GaryH

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