Valve Clearances
 

I'm doing a budget refresh on a stock MSM head (BP4W and stock MSM cams). I lapped the valves and cleaned everything up. I have gaps between .007 and .0125 on the intake side and .008 and .012 on the exhaust.

What is the recommended lash on a stock head running around 15psi on a track only motor with a redline around 7,200? I should have enough shims to mix/match and get pretty balanced numbers if I can figure out what the targets are. Search results are returning crazy values from .007 to .016 and everything in between and OEM recommendations might be too tight for forced induction and track heat. Thanks! :party:

FSM is .0071-.0094 intake, .0111-.0133 exhaust for 99-05.

Thanks Andrew. Any standard deviations for turbo or track duty besides perhaps leaning to the loose side of those specs?

I'm interested to know as well. When I was adjusting my valves I could find very little information online.

I did manage to dig up some part numbers, even they were tough to find.

Mazda Part Numbers and thicknesses so you can order from a dealer. They're ~$9 a piece from Rosenthal.

mm Mazda Part #
2.750 Z5Y1-12-541
2.800 Z5Y2-12-541
2.850 Z5Y3-12-541
2.900 Z5Y4-12-541
2.950 Z5Y5-12-541
3.000 Z5Y6-12-541
3.028 Z502-12-542
3.050 FP07-12-564
3.052 Z502-12-545
3.076 Z502-12-548
3.100 FP07-12-566
3.100 Z502-12-552
3.116 Z502-12-554
3.148 Z502-12-558
3.156 Z502-12-559
3.164 Z502-12-561
3.172 Z502-12-562
3.175 FP07-12-569
3.180 Z502-12-563
3.188 Z502-12-564
3.196 Z502-12-565
3.204 Z502-12-566
3.210 Z502-12-567
3.220 Z502-12-568
3.236 Z502-12-571
3.252 Z502-12-573
3.260 Z502-12-574
3.268 Z502-12-575
3.284 Z502-12-577
3.292 Z502-12-578
3.300 Z502-12-579
3.316 Z502-12-582
3.324 Z502-12-583
3.348 Z502-12-586
3.350 FP07-12-577
3.396 Z502-12-593
3.400 FP07-12-579
3.450 KJ01-12-595
3.500 KJ01-12-597
3.550 KJ01-12-599
3.600 Z5Y1-12-599
3.650 Z5Y2-12-599
3.700 Z5Y3-12-599
3.750 Z5Y4-12-599

List of compatible Nissan Shims that can be purchased from Cylinder Head Supply I bought quite a few shims from them and have been very happy with the sevice and quality/accuracy of the shims. Prices are $13.75 for 4, so they come out considerably cheaper than OEM if you need more than 1.

Nissan compatible shims

Size ----Nissan Part
2.00mm - NISK2-00
2.05mm - NISK2-05
2.10mm - NISK2-10
2.15mm - NISK2-15
2.20mm - NISK2-20
2.25mm - NISK2-25
2.30mm - NISK2-30
2.35mm - NISK2-35
2.40mm - NISK2-40
2.45mm - NISK2-45
2.50mm - NISK2-50
2.55mm - NISK2-55
2.60mm - NISK2-60
2.65mm - NISK2-65
2.70mm - NISK2-70
2.75mm - NISK2-75
2.80mm - NISK2-80
2.85mm - NISK2-85
2.90mm - NISK2-90
2.95mm - NISK2-95
3.00mm – NISK3-00

my 2001 FSM indicates:

Intake: .008-.009
Exhaust: .011-.012

18psi. The FSM does a poor job of converting from metric to imperial. If you do the conversion yourself, you arrive at Savington's numbers.

Sav: are you also recommending that this should be adhered to for N/A, street turbo, and track turbo?

My numbers come from the 99-05 Engine-specific FSM, and they are converted from metric specs. I've used them on turbo builds as well. Trend towards the big side on the exhaust cam gaps.

Thanks - exactly the answer I was looking for.

I just finished this job on my car. Does anyone know if all of those mazda part numbers are still valid? I took a list of numbers to the local Miata parts counter and it seemed like they had consolidated the number of shims they produce.

I had my head's 16 shims and 18 spares and was able to get the intake completely square with different combinations. I ordered 5 shims from MMD to complete the exhaust side and of those, I only found one size discontinued. Two of the five were backordered so hopefully they arrive sometime soon... ...like before April! :giggle:

Pardon my ignorance, but who is MMD?

I went my local dealer because only 1 of the 4 shim sizes I wanted was on Rosenthal. The local dealer only had the same shim available, and his parts system was telling me that out of the 3, only 1 was in British Columbia, and there were none of the others in North America. I inferred from this that perhaps they had consolidated the number of shims they made. I was able to get the last valve into spec by playing with the tolerances and selecting a different shim.

Sub'd.

About to install a new MSM intake cam on Red.

Related -- do you guys put in new shims when you install a new cam? Similar to how it is common practice to install new hydraulic lifters with a new cam? Or is shim material softer/won't wipe a lobe?

MMD is mazdaspeed motorsports development. its website where you buy factory parts for cheap. also known as mazda dev, mazdaspeed dev, mazda comp, etc.

MAZDASPEED MOTORSPORTS DEVELOPMENT - Home Page

put the new cam in, check the clearance, get new shims for ones that are out of spec. I wouldn't bother with any of the others.

Thanks,

I knew mazda had special rates for guys who race. I don't think I had ever heard of it referred to as MMD before.