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689 Posts
Discussion Starter · #81 ·
So the BP4W swap, there's a fair bit of info here so I'll try keep it in some sort of order.

Just to recap, the head is a 1.8 BP4W from a mk2, it's been stripped down and skimmed 20thou, as well as getting the valves recut as they were too far gone for lapping.
49948251372_99ec1ab2e2_c.jpgIMG_20200527_202318_1 by Scott Reid, on Flickr

After machining I stripped it down and applied assembly lube as I wasn't sure when it'd be fitted:
49997707926_a16ee10d73_c.jpgIMG_20200605_191240 by Scott Reid, on Flickr

Bought a mk2.5 "flattop" inlet manifold, as the mk1 inlet would no longer fit, comparison with a mk2 inlet:
49934873667_ed1e0c3de9_c.jpgIMG_20200430_190250 by Scott Reid, on Flickr

As the mk1 doesn't have EGR, I fitted the Jass Performance blanking plates to the back of the manifold. You can also see the set of mk2 injectors, that were sent to Injectortune for cleaning and flow testing.
49997709211_70ed101983_c.jpgIMG_20200611_220321 by Scott Reid, on Flickr

All built up and ready to go on the car:
49997187498_ce66077637_c.jpgIMG_20200611_215719 by Scott Reid, on Flickr

Split the mk1 engine after running through some coolant and oil cleaners:
50179817603_bbb03d2aa9_c.jpgIMG_20200622_182414 by Scott Reid, on Flickr
50180609122_f4dc17c0e1_c.jpgIMG_20200626_183057 by Scott Reid, on Flickr
50180609037_292cf1081a_c.jpgIMG_20200626_183207 by Scott Reid, on Flickr

Used the RevLimiter guide for cleaning the pistons, with some Mopar combustion chamber cleaner:
50180608627_18a71425f0_c.jpgIMG_20200716_204705 by Scott Reid, on Flickr
50179815783_e3f65a133f_c.jpgIMG_20200721_201407 by Scott Reid, on Flickr

Had to invest in a Jass crank bolt removal tool, worked really well and certainly didn't struggle to get it cracked and off:
50180609522_ee25aafeca_c.jpgIMG_20200624_192146 by Scott Reid, on Flickr
50179817263_7e41200e97_c.jpgIMG_20200623_194337 by Scott Reid, on Flickr

Other than that, it was relatively plain sailing, following the Car Passion Channel timing belt video replaced the: waterpump, front crank seal, cam seals, idler/tensioner pulleys, head gasket, exhaust/inlet gasket, coolant sensors at the back of the head, all engine hoses for red stoney racing items.

I also swapped the mk1 starter motor for a mk2 item from Autolink, they were on offer, just to note these only fit with 2 of the 3 bolts and you cannot utilise the mk1 L-shaped bracket either. Where the mk1 unit cranked 3 or 4 times before starting, the mk2 unit cranks 1 or 2. A worthwhile swap.
50180354056_4eb2ff32b1_c.jpgIMG_20200715_201207 by Scott Reid, on Flickr

I also swapped in a mk2 throttle body, so it's now got the revised IACV unit, that's much tidier. Slight modification to the throttle cable bracket (moving the cable to the top slot) but you can use a mk1 throttle cable and don't need a later (shorter) cable.

On a side note, cleaning your expansion tank? use dry rice, worked a treat.

50180607327_429946b4b8_c.jpgIMG_20200730_191220 by Scott Reid, on Flickr

So with new plugs, oil and filters, the car started first time with a bit of help on the throttle. sorted the idle and the timing (14 degrees) ran up to temp and replaced the coolant. Have since been on a couple test drives and have noticed the following:
- Oil pressure is now slightly higher than on the original engine
- Coolant temps sit slightly lower.
- Definitely feels faster as well as smoother on the power.
- Certainly pops louder than it used to.

Plan would be to get it to the same dyno as before to compare the pre swap to post swap, I've also got a Speeduino ECU to fit at some stage, once I get a wide-band to fit along with it.

Anyway, that's quite a lot of information for now, I'll keep testing it until I'm happy to put the under-tray back on.

Thanks for reading.

689 Posts
Discussion Starter · #82 ·
Spent some time at the weekend carrying out a compression test just to see what's happening in the engine, 185/188/184/190
50393432412_c8c88c0499_c.jpgIMG_20200928_105019 by Scott Reid, on Flickr

All seems good, I think my issue is a result of using the supertech valve stem seals, I think I might need to change these to OEM seals, which I'll look into.

Also checked the plugs, now that I'm running mk2 injectors/fuel rail on a mk1 ECU:
50393433857_ce7b95d4e9_c.jpgIMG_20200927_172920 by Scott Reid, on Flickr

This will be getting swapped out for a Speeduino as soon as the cars back from rust repair, which it goes out for today, I'm hoping nothing terminal is found.

689 Posts
Discussion Starter · #84 ·
Healthy compression. Far right plug does look a bit oily though, hopefully the stem seal change fixes it.
Yes glad to see it looked healthy, I'm guessing that's a lot to do with the valves being recut.

I've spoken with the machine shop and they'll swap the valve stem seals free of charge if I can get the head to them. Which should be much simpler since I've already done it once now.

689 Posts
Discussion Starter · #85 ·
Keep forgetting to update this thread, but here's everything that's happened since the last post:

- Supertech valve stem seals were replaced by the machine shop, on inspection almost all of them were leaking, replaced with OEM units.

- Rust on both sills now repaired, slight paint reaction on the drivers side, but will fix in the warmer weather. Both sills also treated and waxed.

- Gearbox taken off, fitted with new seals and replaced rear main crank seal (again), fitted a BOFI clutch kit.

50897533401_42cbca4ab3.jpgPSX_20210131_191754 by Scott Reid, on Flickr

- Fitted some Freaky Parts gauge rings and Laserdash gauge surround.

50922001907_201b1fce9b.jpgPSX_20210207_204354 by Scott Reid, on Flickr

- Fitted some GC Fab door bars and sold the Cobra clubmans, reverting back to standard seats. Modified and refitted trim pieces.

51083298866_723ef7a058.jpgIMG_20210329_191916 by Scott Reid, on Flickr

- Serviced the engine/fuel filter and fitted new cam seals.

- Treated and undersealed the front wings/inner wings.

- Replaced both doors with better condition items.

That's all happened since November last year, in the process of re-insuring the car and booking it in for an MOT next week.

Hopefully next post it'll be back on the road.

689 Posts
Discussion Starter · #86 ·
Time for another update, car passed it's MOT on the first attempt with only 2 advisories, which was a bonus. Obligatory annual MOT picture:
PSX_20210429_153901 by Scott Reid, on Flickr

I fitted some Matte Black side stripes, which in the end didn't work out, so removed them, taking with them some dodgy paint from the rust repair (great!). In the process of fixing paint, then some bronze side stripes will be going on instead:
IMG_20210509_181527 by Scott Reid, on Flickr
Matte black only really works when you've pristine black paint I'm guessing...

Fitted a DaveFab brake stopper:
IMG_20210519_213131 by Scott Reid, on Flickr

Took it on a road trip up to Pitlochry (got fed up of the stiff suspension):
IMG_20210529_165559 by Scott Reid, on Flickr

Fitted a BOFI GV front lip (after it finally arrived):
IMG_20210607_212533 by Scott Reid, on Flickr

Oh and got a 65mm pulley for the M62:
IMG_20210605_110727 by Scott Reid, on Flickr

Still need to fit the ECU and still gathering parts for the SC install, so hopefully that'll all be in updates soon.

689 Posts
Discussion Starter · #87 ·
Just a quick update to try keep this up to date.

After a year of gathering parts went on to sell the pretty complete M62 Supercharger kit I'd been compiling. Instead purchasing a pretty complete Flyin' Miata turbo kit. It'll be running a GT2554R. Looking at getting a BOFI intercooler kit unless there's a better route to go?

M62 Kit just before I sold it all:
IMG_20210808_184429 by Scott Reid, on Flickr

Turbo kit:
IMG_20211118_224403 by Scott Reid, on Flickr

Also working on getting some gauge pods fitted to my spare crash pad:
PSX_20211010_223948 by Scott Reid, on Flickr

Fitted a quarter-light vent (well worth it):
PSX_20210829_204414 by Scott Reid, on Flickr

As well as some bronze side stripes:
PSX_20210620_183104 by Scott Reid, on Flickr

Will try keep this more up to date moving forward, I'll have a few questions re: the turbo install.

689 Posts
Discussion Starter · #88 ·
Managed some time on the car last night, got a second hand Mazda A/C fan, going to wire this in as additional cooling on the A/C button. Decided to stick to OEM over the SPAL unit in this instance. Getting the rad back in was a bit of a chew but got it eventually, longer bolts was the trick.
PSX_20211125_234610 by Scott Reid, on Flickr

Fitted in the temp sensor housing into the top rad hose, it's a bit tight, I don' think it'll leak but will find out on start up.

Space with the 2 fans back in and an aftermarket rad in place:
IMG_20211125_221419 by Scott Reid, on Flickr

Didn't manage a startup last night as it was too late by the time I was done, don't want to annoy the neighbours. Looks like the coolant capacity is up over the standard rad. I'd rather go this route than the coolant re-route, I think I'd go oil cooler before I went coolant re-route.

Since I couldn't start the car, decided to spend some time on the turbo kit, managed to remove all the leftover studs (2 were pretty bent), all the hot-side bolts loosened off on the turbo itself but it wouldn't clock by hand (no surprise), also tried the snap ring on the cold side, it snapped my pliers so I need to get some heavy duty ones instead.

The sensor that came with the downpipe is stuck solid, tried: heat, penetrating fluid, brute force etc. etc.
IMG_20211125_205451 by Scott Reid, on Flickr

Shall persevere, this is the sort of stuff that makes a project go on forever!
81 - 89 of 89 Posts