The V8 Owners Forum -

You brought up the 4" pistons with the Ebay links - Initially I thought I was missing something obvious, then the penny dropped that you might be much more sane than me and not have a collection of elderly cars with Rover v8 engines.

Good call on the Ford pistons - there would seem to be a near infinite number of relatively affordable options when you go for a 94.5mm bore. I'm not out to just spend money for the sake of it - there are several other engine options when the money gets to a tipping point. Until then, I aim to build the most reliable engine I can given my performance aspirations.

Oh and I never said thank you for your kind offer of transport from the other thread - it is much appreciated. I have to go to a work thing on the mainland shortly, so that's got a lot of that expense and hassle dealt with.

Hi
If you are going to be over on the mainland consider Owslebury crankshafts in Winchester for machining work http://www.ocservice.co.uk/ they say they have been going 21 years, it is actually quite a bit longer than that, they did the machining work for a mini engine I rebuilt with my Dad when I was about 11 and I wish that was only 21 years ago. I have not had anything done by them since my early twenties but for them to be still going they can't be doing bad work.
I will be in Winchester on Monday so could collect stuff off youu then, but I will be down other times so let me know If you want to pass anything across.
Best regards
Mike

Some progress of sorts. Getting the logistics sorted out slowly - Everything should be aligned to half term now, so I only have to make one trip to the mainland at my expense on the ferry. It's turned out that I've got a fair bit of work on the mainland this month

I got around to looking at one of the heads. I serviced them 5 years ago and hoped they wouldn't need too much attention. Functionally they seem OK, but I thought I ought to actually measure things this time.

The chamber measurements are 33cc 32cc 28cc and 31cc (to the nearest CC until I get my hands on more accurate equipment) So less than ideal in that it gives a 7% compression difference between the largest and smallest chamber. No wonder cylinder 4 was never all that happy at high RPM.

Once I get the accurate equipment, I intend to match all the chambers to 33cc since it looks easier to take material away than to add it...

Sometimes it's good when your wife works in a school. A-level chemistry equipment is pretty accurate, and all the better for not having to actually buy said glassware.

Taking over the utility room... Not going to risk a kitchen invasion tonight!


Results from using the correct equipment are (not surprisingly) better and less worrying than my attempt to use mass of fluid - my scales claimed 1g accuracy, but obviously they struggle to get to 2g. My faith in TVR is slightly restored.

1: 29.4 cc
2: 28.3 cc
3: 28.3 cc
4: 28.4 cc
5: 28.3 cc
6: 28.7 cc
7: 29.2 cc
8: 29.7 cc

I wonder how much of the (small) variation is down to things like amount of crud still on the valves.

Good stuff, not massive variations. But stick the head in a dishwasher when her indoors in getting her hair done, and repeat. As above, crud may affect redings but only by a few fractions of cc I would have thought.

One of the good things about SWMBO is that she doesn't care if I use the dish washer for car parts. As long as I don't put plates in at the same time...

Sensible of her. You wouldn't want ceramic chips getting in the galleries or anything like that........

phone got upset

Heads in the dishwasher again. Just finished cleaning up after making aluminium filings for most of the weekend. The results are:

cyl 1: 29.4
cyl 3: 29.2
cyl 5: 29.3
cyl 7: 29.5

cyl 2: 29.2
cyl 4: 29.2
cyl 6: 29.2
cyl 8: 29.6 - measurement error of +0.1 last time. Pleased I checked it again (twice)

I'm very happy with this - it gives me a variation of compression ratio of less than 0.45% Photos of my efforts to follow once the parts washer has finished.

It occured to me that I should be able to use these measurements in the individual cylinder fuel trims in the ECU. I am undecided how best to calculate numbers to put in. The larger chambers must cause their cylinder to have less vacuum, so less air in them, so less fuel required, but is this something that tends to disappear at high loads when the pulse width is long, or is it something that will always happen in proportion to the "average" cylinder? Anyone thought about this? Alternatively, they aren't badly matched now so it probably doesn't matter.

Now on with measuring things... Valves & springs this time.

Not much progress, but at least boxes of parts are arriving. The crank is in Midland Balancing now thanks to a small diversion after some meetings for work.

Old and new rods & pistons. Looking forward to getting the rest of it back.


The trial build should be done in half term. Then I can get proper measurements for compression ratios etc.

Does anyone know if the oil pump on a Serp front end has a service kit? It would seem sensible to replace the pump given the miles on it.[/img]

A few delays happened (such as the ceiling in my daugher's bedroom collapsing due to a water leak) so progress has been less than ideal.

I finally have the parts in the garage to do a trial assembly.
Many thanks to all the people involved in getting crank and block sorted out.

I have checked the gaps on the piston rings and fitted them to the pistons and trial fitted the crank. Only 2 minor snags - There were 2 missing 2nd comp. rings when I opened the box and the main thrust bearing shell doesn't fit on the cap due to the alignment lug being in the "wrong" place.

Nice pistons yes there is a serp front cover oil rotor kit available for about £65 I would strongly recommend changing these I used http://turner-engineering.co.uk/ just recently for said item I am also in the process of a build

Thanks

The two snags are now resolved. Can make some more progress now.

Bottom end back together.

All pistons in. I hate those compression sleeve things - they bite!

Bearing clearances all checked and caps all torqued up.

Now on to dealing with the bananas that are pretending to be cylinder heads... And dealing with getting the compression ratio to come out where I designed it to be - The pistons have a slight positive deck height thanks to the block requiring more taking off it than I budgeted. Looks like standard 1.2mm head gaskets are easily sufficient for minimum clearance, but are very slightly too high for compression.