SimonB

Do you mean the boost behaviour is strange using that 4088? If so I'm not suprised considering the chunks missing from the exhaust wheel! Or do you mean with the T67? Has it been remapped since changing?

Next up, file fitting piston rings. This sets the ring gap. Starting with the 1st compression rings, then 2nd compression rings and finally oil control rings you put each into its cylinder. To make sure the rings are square in the bore you can use a special squaring tool, or do it the cheap way and put a 2nd compression ring on a piston and carefully put it into the bore from the top as the 1st pic shows. The ring stops against the block surface leaving the piston square in the bore. You then measure the ring gap using a feeler gauge (pic 2). If it's too small you need to file the ring - I have a ring filer which has a wheel you turn, see pic 3. After it's the right size I used a fine stone to duburr the edges. The gaps were specified in the info I got with the pistons - 0.25-0.35mm for the 1st, 0.3-0.5mm for the 2nd and 0.2-0.45mm for the oil rings. The compression rings are marked to show which side faces up. Afterwards you need to keep the rings organised as each will be sized to the particular cylinder. To do this I got a bit of wood and hammered a load of nails in and hung the rings on once I'd done them. See final pic!

Well spotted indeed! The block edges are nicely radiused off but the head ones weren't. They are now! Are you doing it yourself? You're a braver man than me! It wasn't flow tested no, the guy who did it doesn't have a flow bench he does it by eye and experience.

I have a T67DBB with the 0.68 A/R housing - 625bhp here. It does look very small when you look at it, but it does the job. You could always try the larger exhaust housing anyway - they are quite cheap IIRC. But I would definitely expect more from the 0.68 housing.

Charlie (b'have) kindly popped over this afternoon with his Mercer bore gauge so we are able to answer the "do you need to line bore/hone if using ARP main studs" question. We started by measuring the out-of-round with the stock main bolts torqued to spec. We measured 0.01mm out on 1, 0.015m on another. Then I installed the ARP studs and again torqued to spec (70ft/lbs with assembly lube). Somewhat suprisingly as I expected it to make no difference, we measured them as absolutely bang on round. In any case 0.01mm out-of-round is fine. So I guess the conclusion is you should be absolutely fine using the studs without line boring, but it's nice to check! We also checked the cylinder bores for taper and out-of-round. We measured the worst one at 0.02mm taper (i.e. there was a section that was 0.02mm wider than the rest). We concluded this was pretty much fine, don't know if anyone else has an opinion?

Time to lap in the valves - the seats have been cut to the valves, but lapping them in confirms they are seating properly. To do this you need some fine lapping paste and a stick - this is basically a wooden stick with a couple of rubber suckers on. You apply a fine line of lapping paste on the face of the valve, then slip it into its guide and onto its seat. You stick the sucker on the center of the valve head, apply light pressure and rotate it back and forth between your palms. It starts off making a course gritty noise which quickly smooths out - once it has you wipe off the paste from valve and seat and you should see a thin continuous satin-finished pattern the same width round the valve and the seat. I've tried to show this in the pics but it's hard to take a photo of! They only took a few seconds to lap in. This pairs valves with individual seats, so you need to keep them organised afterwards so you know which one goes where. To do this I used a bit of carboard and poked the valves into it as I lapped them. The first pics are an unlapped valve and seat, then the lapped ones. The next pic shows the lapping paste applied, lapping a valve and finally my hi-tech valve organiser!

Valve time. I checked the valve stem to guide clearances. To do that you measure each valve stem using a micrometer. Then measure the guide bore - I used a small hole bore gauge for this. You put the gauge into the guide and turn the knurled end which expands the gauge until you feel light resistance. Then you take the gauge out and measure its diameter with the micrometer. Subtract the stem diameter from the bore diameter and it should be between X and Y for intake, X and Y for exhaust. If it's too tight you would need to ream out the guide - mine were all spot on. EDIT:Ooops, just noticed I never filled in the actual values (X and Y) - I'll do that later when I get a chance!

He also balanced the pistons for me - they were actually a fair bit out (when I say a fair bit, I mean 0.5g ). They are now within 0.1g - the heavier ones were lightened slightly by chamfering the ends of the pins slightly which avoids having to dress the pistons. The rods were also end-to-end balanced to within 0.1g by shaving the top and/or bottoms slightly where needed. The actual weights of the pistons were 447.3g (with pins but not rings) and the rods were 601.2g. For context, I believe the stock pistons are 539g with pins and the stock rods are 761g (not sure if that includes the bolts or not). The other thing I had him do was clean up the sumps and oil pickup in the washer - they came out lovely and clean which saved me a horrible job! First thing I did after I got it back (after nearly giving myself a hernia getting it out the boot) was to clean the block up. It had been cleaned anyway, but no harm in doing it again to make sure there was no metal particles left from machining. I washed it with detergent, a pressure washer and some engine cleaning brushes for the oil passages then dried it and used a blowgun on my compressor to make sure the machined surfaces were perfectly dry before spraying them with WD40 to stop them rusting. I then painted the block which was a bit rusty and manky looking using POR15 engine enamel from Frost. I used their metal ready which is an etch primer first on the block and then a couple of coats of black enamel - it looks pretty good now I think! With that done it was back on the engine stand. I then set about removing all the old silicon gasket material from the sumps, rear oil seal housing and bottom of the block. Not a nice job! You definitely want Loctite 7200 gasket remover for this - it softens up the silicon but you still need a razor blade scraper and plenty of patience to get it all off.

Before I gave it to him I worked out the volume of the combustion chamber I wanted for a 8.5:1 compression ratio, and they made them to that volume for me. Ok, so compression ratio 101, pay attention at the back . The compression ratio is the ratio between the swept volume (the displacement of one cylinder) and compressed volume (the volume above the piston at top dead center). The swept volume is easy - the formula is: pi x (bore/2)^2 x stroke. So for me that's 3.14157 x (8.7/2)^2 x 8.6 = 511.24cc The compressed volume is made up of several things: cylinder head combustion chamber + gasket volume + deck clearance + volume between top ring and piston top + piston top. (see attached pic which I've stolen ) gasket volume is 3.14157 x (diameter of the gasket bore hole/2)^2 x compressed gasket width. (You need to measure the bore hole in the gasket) For me the HKS gasket I'm using is 1.6mm and the bore holes are 88mm so that's 3.14157 x (8.8/2)^2 x 0.16 = 9.73cc Deck clearance is 0 in my case (this is how far above or below the deck of the block the piston is at TDC). I'm not bothering with the ring volume as it's so small. The piston top bit is positive if there's a dish in the piston top and negative if there's a dome. In my case the JUN pistons have a 12.7cc dish so that's +12.7cc, so compressed volume for me is: combustion chamber vol + 9.73 +12.7. The compression ratio is (swept volume + compressed volume) / compressed volume. I've lost my re-arrangement of the formula to work out the desired combustion chamber volume now, but it worked out at 45.7cc. That's because 45.7+9.73+12.7=68.13, and (511.24+68.13)/68.13 = 8.5. Got that?

Right, this thread is long overdue an update! I got the machined block and head back a while ago. The block had been cleaned in a parts washer, then bored and honed. It was skimmed slightly to make it absolutely flat (it was pretty close anyway). The head was cleaned up, old valve guides pressed out and new Ferrea ones pressed in. It too was skimmed to make it absolutely flat. Then the seats were cut for the +1mm Ferrea valves and the head ported and matched to the exhaust and intake gaskets. It's a relatively mild port, but cleaned up inside a fair bit. He also repaired a thread on one of the core plug holes which I had mullered getting the plug out - it was machined, tapped for a size up and a new brass plug screwed in and sealed. Lesson learned - don't bother removing the core plugs from the head! Here's some pics of the head.

Depends if it's a UK spec - if so that's true but if it's a Jspec with a MAP sensor it won't be overfueling.

I have no idea what you're talking about, but it sounds bad...

I would get a load leveller from Machine mart: http://www.machinemart.co.uk/shop/product/details/cll500-load-leveller That lets you tip the engine back and forward, should make life a lot easier!

One of the advantages of living alone - I can leave car parts all over the place. There's currently a clutch disc in the lounge, pistons, rods and various other engine bits in the 2nd bedroom and various engine internals I've just cleaned in the kitchen. Very handy having a built-in parts washer* in the kitchen... *aka dishwasher

Sounds like a quick drain jobbie - they have a spring loaded valve you can connect a hose up to and suck the oil out.

No true. Trouble is most aren't just carbon fibre, they are carbon on top of fibreglass and weigh more than the standard bonnet. Varis do a pure CF one I believe.

Those things are a PITA for us (NATS) as they cause radar reflections. It's expensive to sort out and nobody knows who's going to pay for it - should be the turbine operators really.

If you have Euro/UK/USA spec 550 injectors on a Jspec you need a resistor pack. The import uses high impedence injectors and the Euro ones are low impedence. Euro-spec cars come with a resistor pack for this reason. Don't run the Euro ones without a resistor pack, you will do damage!

Nice one Tony, that will come in very handy...

In a hotel? You big girl...

To be honest you'll be lucky getting a camping spot if you just turn up these days. There might be some left at some of the crap sites - it's gonna be a major PITA driving around to find somewhere though.

I never bother with deflectors. I bought some once years ago and couldn't figure out where to attach them. I never really drive at night over there anyway.

Owen's installed mine as part of my install, I assumed it was a Motec item. You could ask them.

Nope, 62mph is 100kph, simple as that.

I'll be there on Saturday. Sunday worth avoiding I reckon if Hamilton is there - it'll be mayhem.