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Discussion Starter · #22 ·
Finally got the new head on the car. Got fed up of waiting for the new shims for the shim under bucket conversion, so used the standard set for now, will just mean I can't yet go over the stock rev limit which shouldn't be too much of an issue yet.

Took a bit of time to get everything switched over, and adjusted well but think I’m there. Ended up using an endoscope camera to check I had plenty of valve clearance, especially when the intake cam is on full advance, as the valve is cracking open whilst the piston is still on the way up the cylinder but looked fine. Potential to skim the head further in the future to increase compression as well, but not sure by how much yet.



Was very nervous on first start up given what was at stake. Made sure everything was spinning freely then turned over without spark to make sure I had oil pressure. Then gave it a push and it started up straight away, not even any lumpy idle which I was kind of hoping for lol.

Had a bit of trouble getting the vvt to start working again, then remembered the stiffer valve springs likely meant the vvt needed more duty, so that started working again following a few tweaks to the mapping.

Anyway, now been out and mapped a few times and it's pulling a lot harder. Redline is still at 7400 for now, so more to come, but feels quite a bit quicker at top end, suddenly comes on strong after vvt at 5k revs or so and sounds a lot more intense than it did. Virtual Dyno suggests 160bhp but not quite sure whether that's right just yet.

Still keeping the exhaust bung in for now so potentially losing some horsepower there too.

Next job is a better exhaust manifold, and do some port matching work to the Jenvey inlet manifold as I think there is a bit of a step to the head which won't be helping things.
 

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Discussion Starter · #24 ·
Lots of work on this car of late, but not much actual progress. Recently fitters a new GCfab roll bar unfortunately didn’t receive the lower spreader plates so it’s in place but not fully secured as yet.

The engine is also out for a rebuild, whilst looking at the cams I found a tiny flake of metal, so pulled the filter apart abs found some more so decided to pull it out. Had a set of 85mm 12:1 pistons waiting anyway so it was a good excuse to rebuild. Ended up finding a very worn set of thrust bearings so that was the root cause. Anyway block has been to the machine shop and is ready for the rebuild and inevitable piston crown grinding due To valve contact.

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In the meantime I decided to drop the subframe while the engine was out and address the rust. Front chassis rails had been patched but were clearly very bad underneath it all don’t have any pics but will get some and front repair sections are in the post.

While everything was out made sense to refresh bushes and de rust all the arms. Lots of work on the wire wheel later I’m getting there on those. Silver car and silver wishbones. Not sure whether that was wise but wanted something other than black.

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