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layabout
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Discussion Starter · #441 ·
had another 5 mins, a hydraulic press, an impact-screwdriver, an old waterpump and oilpump from a Mazda engine....


and a sandblasitng-cabinet ;)

I'll remove the old snapped cambelt-cover bolts at a later date (if I remember?)


I wanted a 1.8 / later 1.6 oilpump as it has the mount-boss to accept the later (mk2?) crankshaft position sensor and with the drysump setup's remote oilpump there waas no need for standard type oilpump gears so stripped out & binned....
the waterpump is stripped purely because I can although it will come in handy when I'm casting the 'Hardblok' in the cylinderblock's coolant jacket.


the oilpump casing has a redundant dipstick tube position, a reminder of the Mx5 engine's roots as a 1.3 fwd Mazda 323 powerplant.


better photo showing the dipstick tube's 'blanking-plug'and also the bolthole boss to accept the crankshaft position sensor (although this needs tapping - an easy task.)

something that struck me (rare moment of clarity maybe?) was that the redundant dipstick tube hole could be re-purposed for an oil catchcan drain / return to the sump :unsure: NOT of use with my drysump setup but maybe something worth considering for other engines?

Rich.
 

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layabout
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Discussion Starter · #442 ·
another quick 5 mins on the car, well maybe 25 mins on the front cover / oilpump case...


removed the siezed / snapped bolt stubs, first attempt on both so I'm pleased with the outcome :cool:


weld-built the stubs then welded an M10 (17mm hex) nut onthe stub.
one was proud and the other under-flush.


light sandblast later then ran an M6 tap through all threads to clean.
also threadded the hole to mount the crankshaft sensor - drilled out to 5mm and ran an M6 tap down it.


also trimmed the redundant oilpressure-relief valve mount from the cover, this could have stayed but cutting it off gives more room around the front of the sump pan where the front 'scavange' / pickup will be positioned.

another piece of the puzzle 🤡


Rich.
 

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layabout
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Discussion Starter · #443 ·
something I forgot to mention, if anyone is looking at fitting a trigger-wheel/crankshaft position sensor to an earlier engine that didn't have one, firstly you need an oilpump housing from a 1.8 engine (or maybe any post '93? iirc all mk2 / 2.5 have this anyway) that has the mount-boss I threadded earlier, then you need to trim / remove the cast lug thats in the way of the sensor fitting squarely....


the lug that needs removing....


where the sensor fits.


sensor removed showing the trimmed & filed area that the sensor mounts against.


another view of the sensor.

I'm wondering if there should be a tube-dowel to locate the sensor in the casing as it's somewhat slack on the M6 bolt, will look into parts diagrams & maybe machine one if not...

more thoughts to follow....

Rich.
 

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Happily expanding the To Do list since 1997
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The sensor has a metal sleeve in its bolt hole to stop the plastic being crushed but I didn't need more than that to fix it rigidly. If it's slack maybe the bolt is bottoming out in the oil pump housing.
 

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layabout
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Discussion Starter · #445 ·
The sensor has a metal sleeve in its bolt hole to stop the plastic being crushed but I didn't need more than that to fix it rigidly. If it's slack maybe the bolt is bottoming out in the oil pump housing.
I've seen the sleeve (9mm Od & 7mm Id) but was more thinking about repeatable positioning as the bolt (M6) is a clearance in the sleeve so if the sensor is removed / re-fitted then it could be a slightly different position & therefore different timing reference to the ecu....

I'm probably overthinking & over-engineering this :unsure:

Rich.
 

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I see what you mean. I suppose if the sensors need replacing every so often I might use a bit of rubber sleeve on the bolt just to centre it in the sensor's hole.
 

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layabout
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Discussion Starter · #447 ·
was digging in the shed & tripped over an odd 6mm wheelspacer so decided to try my Enkei 'M' edition (6x15" et45) 5 spoke wheels over the Wilwood Dyynalite / Supermiata 'Boxmount' bracket combo.


plenty of clearance :cool:


have a few mm clearance between caliper & spoke - unlike without the spacer ;)

my Compomotive MO wheels clear so only need a spacer for these Enkei's, not an issue as I've longer studs fitted to the hubs I'll be using.

Rich.
 

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layabout
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Discussion Starter · #448 ·
eventually decided on the passanger front brake line route...

been looking, thinking, looking again & trying to visualise all interactions with other components including the exhaust (HOT) and the wheel (rotating / throwing stones etc.)


gave up, drilled some holes and made a flexi-hose o_O


another angle...


where the bulkhead fitting passes into the underarch, away from evrything (hopefully 🤡)

this will be replicated on the drivers side - but will have a direct feed from the master-cylinder.

Rich.
 

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layabout
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Discussion Starter · #449 ·
had another look at the passanger side underbonnet brake hose as I wasn't happy with the routing.


I reversed the 90* bulkhead fitting on the bulkhead so it accepted the straight fitting underbonnet & the 90* fitting inside the cabin like the drivers side.


this meant drilling another hole so the bulkhead / hose fittings cleared the bulkheads sheet-metal pressing. I'll find a use for that hole like maybe Lambda sensor?


over to the drivers side & eventually made / fitted the last underbonnet brake hose.


nearly the routing I was hoping for...


front view of the routing.


photo-spamming...


with throttlebodies fitted.


sorta what the final view will be (ok, theres some wires to add but thats being picky...)

Rich.
 

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layabout
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Discussion Starter · #450 ·

jetwahed the 1986 Mazda 323 turbo / B6t cylinderhead yesterday, was from an engine that had been idle for over 20 years and it looks like I have not done anything :ROFLMAO:

note the burnt exhaust valve in number 2 cylinder, this is the cylinder with the least cooling in a 323....

^^ poking holes in the theory that mx5's need a reroute to have 'proper' cooling like the fwd engine that was designed :p


inlet port, seems same as Mx5's B6ze(rs) engine.


exhaust manifold uses the 'extra' manifold stud hole (front & rear) that's left unused in an Mx5 enginebay. port looks identical.


something I noticed on this head.


the camfollower bores are 'relieved' to allow larger-lift camshafts to turn without collision.

compared to a 'standard' Mx5 type B6ze(rs) cylinderhead from ~1989


cast with slight relief but not neatly machined (inlet side)


exhaust side.

so, is this Mazda cutting time / machining costs along production OR something specific to the B6t? - I've heard & read several times that the earlier the head casting the better the finish / cast-quality and even core positioning for the coolant jacket :unsure:

something that'snow making me consider starting portwork on this head.....

Pam Fi Duw?

Rich.
 

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layabout
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Discussion Starter · #451 ·
off on another tangent again, removed the exhaust from the silver car


its a Cobalt thing that I'd modified by replacing the oversized tailpipe with straight tube.


the task was to assess the possibility of using one of the Tony-Law repackable silencers I have. this is the smaler diameter silencer.





this is the larger diameter silencer.




this one is thicker in profile than the Cobalt but still smaller than the standard silencer.

this Cobalt is not going back on the car so is filed away untill it finds a new owner, I'll fabricate a new system from 2 1/4" pipe and suitable bends with slip-joints as opposed to bolted-flanges.
as to mounts I'll be using Ford's 'pignose' rubbers and fabricated brackets (1'x1/8" steel bent to a 'C', one welded to silencer and it's opposite bolted to floor) as this makes for a strong & flexible system and good resistance to impact - obviously my local roads are in great condition! :unsure:

suppose I need to get on with the manifold now before making the system as it needs to start at the front...


Rich.
 

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layabout
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Discussion Starter · #452 ·
more B6t head stuff...

stripped the head & sent it through the partswasher for 2 cycles.


bit cleaner!


the old headgasket material was seriously welded to the head surface, lots of swearing & scrapeing to remove >:D


general condition looks good considering it was an old rallycar turbo engine & had been idle for ~20+ years...


inlet ports seem to be same shape as the later B6ze(rs) heads as on Mx5's.


same with the exhaust ports although the 'short radius' / lower edge of the port seems smoother and nicer shaped than the Mx5 heads I've seen - doubt it's anything special though :unsure:


I've included this photo as it shows the coolant passageways accross the chamber & ports from the thermostat area (rear of head so number 4 cylinder) - interesting to me anyway.


the cam bearing / cam follower gallery.


closer photo showing the machined relief to allow cam-lobe totation / clearance. I'll measure the standard head on my silver car to compare a production 1.6 Mx5 later.


exhaust camshaft fitted.
this is a 'standard' 7.9mm lift camshaft BUT I have no idea if it's a turbo or na item (Mx5 also used 7.9mm lift).


closer view.


3/4 view, plenty of space for more aggressive camshaft :cool:

more to follow...

Rich.
 

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layabout
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Discussion Starter · #453 ·
looked at another head, this one is on the silver car - Nov 1991 build Eunos Roadster with a Long (Big?) nose crankshaft engine that went well BUT had dubious casting of an inlet port...


~180,000km (110,000 miles?) has taken it's toll, lots of burnt oil staining on the casting 😲


seemed to have hardly any 'relief'


hard to see any gap between cam & follower-boss.




better photo.


again, no visable relief cast into the head.....

as I was playing, decided now was a good time to test-fit (or, find out how much it doesn't fit?) the Tony Law exhaust manifold...


it nearly fits!


plenty of room around the bulkhead / number 4 primary pipe.


but it doesn't fit to the head - something is holding it away :unsure: - can see how far away number 2 & 3 primary pipes are from the cylinder block / close to the chassis.


the offending collision. I knew this was going to happen & have plans afoot to alter pipe angles rearward (known since I bought the manifold as a gamble....)


better photo of the (hopefully) final positioning-ish, can now better plan oil-pipework from pump to oiltank.


the hight of the pipes :confused:


and proof that the bonnet needs massaging (or removal of some internal braces?)
paint will burn & aluminium bonnet-skin may melt!🤡


and, in the great tradition of 'because' I test-fitted the 323 camcover....


not sure if I prefer the origonal Mx5 type :unsure:

more to follow, may cut / section the head on the silver car as it's 'spare' as I want to see where the coolant jacket is in relation to the ports - for scientific purposes obviously :ROFLMAO:

Rich.
 

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layabout
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Discussion Starter · #454 ·
curiosity got the better of me & I decided to check where the manifold hit the bonnet...


tried copperslip on the obvious (tallest) primary pipe - number 3 & there was no witness-mark on the bonnet.


spread some on number 2 primary & had a result...


here.


and on this brace, do I remove the brace or just trim to make clearance?

also, curious as to what cams were in the silver car & compare p/numbers with the cams that were in the turbo engine.


B660 & B61P in the silver car.


B660 lobe shape.


B61P lobe shape, looks to have more duration than the B660?


B660 in both inlet & exhaust from the turbo engine.

google says that B660 is the 1.6 115hp inlet cam and the B61P is the 115hp exhaust cam.

^^ this begs the question about the pair of B660 in both inlet & exhaust from the 323 turbo engine, in-ex conversion?


Rich.
 

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layabout
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Discussion Starter · #455 ·
stripped a pair of rear hubs from lower wishbones today.


went medeval on them with a hacksaw as I wanter the huns but didn't trust the ~31 year old wishbones...


I bodge therefore :ROFLMAO::ROFLMAO::ROFLMAO:

anyway, on a different track, was looing at engine valves, can buy supertech items (with varing reports on quality?) from hamerika but thought I'd look if REC listed anything Mazda suitable...

found theit homepage.

seperately a catndog listing pdf...


with this snippit:cool:

will email or maybe phone in the future & ask if theres anything available & possibly lighter than the mentioned turbo spec items...

more tangents to follow...

Rich.
 

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Happily expanding the To Do list since 1997
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The witness mark on the bonnet rib: did the manifold stop the bonnet closing or did it close but leave a contact mark? If the latter I'd just take a scallop out of the rib. Moderately generous, as the engine will rock, but there should still be enough rib left to maintain some of its strength. Piece of cake to get crafty with a Dremel as it's aluminium.
 

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layabout
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Discussion Starter · #457 ·
The witness mark on the bonnet rib: did the manifold stop the bonnet closing or did it close but leave a contact mark?
erm, about that.....


I posted this photo but maybe didn't caption it properly🤭 it's across the passanger front wing (with my finger in the way) looking at the raised headlight cover (left) and non closed bonnet - sorta 1/2" @ front...

If the latter I'd just take a scallop out of the rib. Moderately generous, as the engine will rock, but there should still be enough rib left to maintain some of its strength. Piece of cake to get crafty with a Dremel as it's aluminium.
just chop the middle rib out, add lightness as Colin Chapman used to say:p

tinsnips work well....

also, I can adjust the hight of the engine as it's not governed by standard sump depth because of the drysump setup(y)

Rich.
 

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layabout
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Discussion Starter · #458 ·
right, head off the silver car & it don't look bad 😲


I was expecting the bores to be worn & all kinds of hell in the chambers / piston crowns :unsure:


not great, not terrible :ROFLMAO:


much burned oil 😲


sooty but clean, was running a bit rich before stripdown but when driven was nice;)


wiped over with a petrol (E5?) soaked rag & revealed shiney pistons...


as I had the rag, wiped the bulkhead and managed to remove some of the rusty coolant leak staining.


also, something I forgot to add a few days ago...


standard 1989/90 Mx5 B6ze(rs) cylinderhead front face.


1986 Mazda 323 turbo B6t cylinderhead, the coolant port id blanked with a coreplug and not drilled to accept the Mx5 type thermostat housing.
also, the casting seems to be much smoother and neater.


another add, camshafts...


the B6t head & B660 cams (fitted) the other cams are the 115 hp Mx5 items...

note the numbers 1 & 2 in the shafts (between front bearing & first lobe), was this relavant to intended use & the B6 as a 16v engine's roots as a turbo primarilary then na in the 323?


the rear of the inlet cams.


rear of exhaust cams.

the older cams from the 323 turbo also have nicer / smoother cast surfaces - due to age or blind luck?

Rich.
 

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layabout
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Discussion Starter · #459 ·
decided to 'add lightness' (& some space for oilpipework) by trimming a section of innerwing/bulkhead gusset.


this area is commonly removed on both sides for V8 or LFX engine conversions and doesn't seem to cause issues with bodyshell strength - not that I'll leave the area rough-cut as it'll get a strengthening panel welded in to replace the missing section.

this allows easier fittment of the drysump oiltank's 'scavange' pipework as it only has to pass through a single-skin andalso gives easier access to the gearbox / engine bolting.

Rich.
 

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layabout
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Discussion Starter · #460 ·
reading through the FIA homologation papers for the Mazda 323 turbo

FIA Historic Database group N (showroom spec.)

FIA Historic Database group A (modified.)

pdf https://historicdb.fia.com/sites/de...401/homologation_form_number_5286_group_n.pdf



engine dimensions...
also that the 1.6 has a cast iron crankshaft, thought they were steel :unsure:

interestingly the Mx5 (mk2 only?) homologation pages show the 1.8vvt engine as having a steel crankshaft (I've cut a mk1 1.8 crank & can attest that they're steel)

on a different tangent, found a tooth-count chart of the available (or, once available?) diff ratios suitable for Mx5, rx7 & Honda S2k


I have a 4.778:1, want the 5.12:1 but theres a shorter 5.3 out in the wild somewhere ;)

annoyingly I've found a website for a company in Los Angelies advertising the 5.12:1....


but no longer available, Bugger:mad:

more searching....

Rich.
 
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