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bad photo of the enginebay less inlet manifold...


the clutch hose routing I've decided on using, theres a deliberate 'twist' and I'll mount the hose against the bulkhead / chassis 'lip' (but that's another story & photo's)


as the inlet ports were uncovered, curiosity made for inspection...
this is the inlet port of number 2 cylinder.


this was the inlet port of number 3 cylinder


another view, theres an obstruction cast into the port
looks to be a remnant of the casting and leftover from a gap in the moulding cores.
I am suprised this slippped past quality inspection!

also, even with the miss-cast port the engine performed well and even after 30 years and how many miles (kilometers?) - wonder what else I'll find when it's stripped...

test-fit of the Hayabusa itb's...





first trial fit of them on a car, I now know my measurements were good (& I can easily get away with longer tb spacer-adapters and still fit a filter or airbox)


something I didn't quite expect was the proximity of the rear throttle-body and the clutch master cylinder!


clearance?


clearance IS clearance isn't it?



Rich.

Looking promising! FYI the casting and machining on some of the B6 and BP heads was absolute shyte. Junk like yours in the inlet port and major mismatches between manifold and head are not rare. If it were mine I'd take the head off, tidy up those ports with a Dremel (or better still a die grinder if you have one), bowl them out a fraction under the valve seats and find another 4 or 5rwkw, along with a freer spinning motor.

I was going to ask if your car had been underwater due to all the corrosion, then I noticed your location in the UK. I bet the underside and all your suspension components are covered in rust.

manga_blue wrote:Looking promising! FYI the casting and machining on some of the B6 and BP heads was absolute shyte. Junk like yours in the inlet port and major mismatches between manifold and head are not rare. If it were mine I'd take the head off, tidy up those ports with a Dremel (or better still a die grinder if you have one), bowl them out a fraction under the valve seats and find another 4 or 5rwkw, along with a freer spinning motor.

interesting to know it's not freek I've stripped 3 x mx5 1.6 B6ze(rs) and one Mazda323 turbo (B6t) engine and this was the first 'bad casting athough the others were older ~1989 & 1986/7? so better mold / cores in the foundry maybe?

I'm building another engine so this head will be spares (was going to section it to see the waterjacket )

old photo's so things are slightly different now...


I've a 110v die-grinder that gets a lot of use (great when welding!) and its done ~20 hours work on modifying a head & matching the Jenvey inlet manifold


roughing the blend, the miss-match had the manifold ~3mm higher than the heads port, not a bad thing as shaping the port-roof is better than the port-floor


~ +3mm each side & top of port (in head)


starting to get there?


the inlet are mostly finished - think I'll quit while ahead before breaking-through into coolant-jacket or valve-gallery

still have the exhaust to finish though (why I want to cut another head to check thickness )

Rich.

Downsized my rims to 16inch from 17. Still black. I think I can feel the difference?

Adjusted the handbrake, at the pads and at the handbrake itself. Chasing an annoying squeak from the rear passenger wheel that only appears when applying the brakes and then only when warmed up.




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Chuppa wrote:Adjusted the handbrake, at the pads and at the handbrake itself. Chasing an annoying squeak from the rear passenger wheel that only appears when applying the brakes and then only when warmed up.

Coincidentally, rear pside calliper is the one where internal corrosion usually occurs primarily affecting the handbrake.

93_Clubman wrote:Coincidentally, rear pside calliper is the one where internal corrosion usually occurs primarily affecting the handbrake.

Thanks Clubman, good to know.

Chuppa


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thought I'd replied to this sorry

bruce wrote:I was going to ask if your car had been underwater due to all the corrosion, then I noticed your location in the UK. I bet the underside and all your suspension components are covered in rust.

thats about correct, this is a jdm car that was imported to UK in 2000 so has fared better than an equivilent 1991 UKdm car - that would probably be doomed

Rich.

thought I'd replied to this sorry

bruce wrote:I was going to ask if your car had been underwater due to all the corrosion, then I noticed your location in the UK. I bet the underside and all your suspension components are covered in rust.

thats about correct, this is a jdm car that was imported to UK in 2000 so has fared better than an equivilent 1991 UKdm car - that would probably be doomed

anyway, done some more on the silver heap....


fitting a vw polo rad


crossflow & twinpass, also narrower than the normal NA item...

Rich.

Zed wrote:roughing the blend, the miss-match had the manifold ~3mm higher than the heads port, not a bad thing as shaping the port-roof is better than the port-floor

My BP05 head had a 5mm diagonal mismatch between inlet manifold and head, leading to a 30%ish reduction in port area - far too much to correct with porting. I had to oval out the manifold bolt holes (a lot) and drill dowels into head and manifold to make them line up for assembly. Exhaust manifold wasn't much better for either OEM manifold or JASMA aftermarket. Reamed out the manifold holes and sleeved them to get a match there.

That head is looking really good!

Zed wrote:still have the exhaust to finish though (why I want to cut another head to check thickness )

I wouldn't worry about cutting through. Exhaust ports are usually thicker and there are very little, if any, gains to be made in opening them out anyway. All you need to do is just remove any obvious casting faults, bowl under the valves a fraction and make sure there's no overlap with the manifold. Having exhaust ports smaller than the manifold holes is no issue, you don't need to blend them. You have a nice rough finish on the inlet ports, exhaust ports gain (at least in the short term) from finer polishing

I've gone a little crazy over the last few months...
Fitted a duck tail, short console and tombstone from Carbon Miata. A Mazdaspeed side brake lever and Roadster scuff plates found in Japan. Chassis rail reinforcement, gear and side brake boots, vintage style window switch, door striker covers and vent rings from Jass Performance and AC vents from a 3rd gen Eclipse.

Some nice updates MonkeyBritchers

The car is looking good, Monkey!

26-28/3 - raced at morgan park,
3/4 engine removed
the rest of April -
Pull head and sump off current engine
build new bottom end with high compression,
strip, clean and check head
assemble engine,
engine dyno,
install engine,
take engine back out cause I forgot the clutch release bearing
chassis dyno
20/5 - General Practice at QR - exhaust manifold broke, fitted spare, got other one welded
21/5 - Rd 3 Production sportscar championship, Qualified p2 in class by 1 tenth, fitted newly welded headers, set a new pb around national almost every session