Project London Bridge

[biznatch]

I didn't greatly enlarge the runners, just cleaned up the irregularities in the casting and smoothed them over to reduce resistance. I opted against opening up the runners so I could keep a good velocity through them - this won't be an all-out race engine by any means and there are some compromises to keep some manners for street driving. Next big challenge will be modifying the Nikki, Port matching, tuning etc. Based on the current rate of progress this may not be finished for quite some time.

[TOOL]

Nice one Glen.

I wouldn't have opened up the runners too much either for that same reason.

How much did you notch the housings for the bridge?

Got any better shots of the exhaust ports?

[biznatch]

Some pictures of the exhaust ports to give an idea of the before, during and after. The intake ports were done using the Racing Beat bridgeport template, exhaust with the Rd race template. I'm not sure whether you can make out the notch in the housing from the last photo, but it was about 2.5mm notch with a 1/4" overlap of the eyebrow at each end.
I'll try to put up some clearer pics when I get back to the UK next week.

[TOOL]

The ports look great. How many hours invested do you reckon?

Those seals look familiar.

[biznatch]

Yeah mate, I'm glad I opted for the carbon seals, solid corner seals and later model corner springs, should be a good runner once it's run in. Well worth making the trip out to Maidenhead to pick then up

It's hard to be accurate about how many hours it took to get to this point because I've only been able to get a few hours here and there over the last 6 months. With all the cleaning, porting, polishing, lapping, etc I would say about 80 - 100 hours which is far longer than I thought when I began the process. With a proper die grinder and parts washer this time could have been much less.

[TOOL]

Did you hand lap?

[biznatch]

I hand lapped the plates. About 45 mins per pair of faces against each other using valve grinding paste. Can't remember what brand it was but it came in a small tin that was double ended (uh-err!!) with fine paste one end and course the other.
The plates came up nicely, not perfect but most of the wear has been taken down and there is now a nice flat surface for the seals to bed into.

It was hard work and I'm glad it's done

[TOOL]

Lol, yeah it's an endurance event alright.

Good to see someone else trying it. Looking forward to the results

[biznatch]

New (remanufactured) shiny bits.
FC alternator, starter, sump plugs.

[KiwiDave]

Mmmmm. Shiny bits