GSlender's Track Beeotch!

[madjak]

Maybe you have a faulty thermostat. In my car I see a nice smooth temp curve but I also have very fast coolant flow as I have no thermostat acting as a restrictor. The water body is heated as one.

Lets assume your cts is correct it may mean the flow is slow enough to keep the water in the engine and get heated to a higher exit temp. When under load the engine is somehow cycling better. It doesn't really explain the almost linear linkage of temp to throttle though. Temperature transfer is nearly always slow to change and lags behind the input energy. Especially when water is used as a transfer medium due to it's specific heat index. (Yay for Y11 physics)

I can't see a way to explain those logs unless it's pressure or electrical.

I would really like to know the answer though!

[Magpie]

Here is a screen dump from the last session of Time Attack rnd 5. There is no change on water temp (green line in the middle of the screen) either at full throttle, lift off in fact it is stable... The EGT's follow what is expected of any engine.

The inHga is brake pressure boost, this was done to see how much vacuum the ITB's were making for the brake booster.

Water Temp by Eipeip, on Flickr

[gslender]

This is the entire 14 mins with of track time and I'm not thinking that this CLT graph looks a) like it has noise and b) that I've got a normal cooling system working as it should - I'll figure it out, but hoping it isn't the head!

[Magpie]

Do you log any other channels? Is oil temp doing the same as the coolant?

[gslender]

Do you log any other channels? Is oil temp doing the same as the coolant?

I can and do log heaps of stuff, just don't have an oil temp sensor - just haven't bothered to go beyond the stock sensors and what is actually needed to run the non-stock ecu.

[Magpie]

Looking at the graph and ignoring highs/lows the data suggests that it is a progressive rise in heat, as should be expected. The peaks at the end would be expected as air flow across the radiator decreases and heat soak takes over.

If you had an oil temp then you would expect to see a similar trend.

[gslender]

Pulled the trigger on a set of used high-lift BP cams and under bucket lifters all for a good price (thanks zossy1)

Did some checks on the cams and by my measurements, they look to be as follows...

Intake is 29.5mm base with 10.5mm lift
Exhaust 31mm base with 10.5mm lift

Pretty happy with that and in the next few weeks, I'll look to begin the installation!

I don't have any shims for the under bucket lifters, so was going to install them and then use existing over bucket shims to get a measurement and hopefully that will be an ok way to get close to the factory clearances - does anyone know if you use the same clearances or not when changing to under bucket lifters?

G

[manga_blue]

They're most likely different. I bought a cheap set of 8 lash caps for the shim-under lifters, all the same size and close to what was needed. Then I fitted the set to each cam in turn and measured each clearance and from that calculated and ordered the size that each lifter really needed.

[gslender]

I bought a cheap set of 8 lash caps for the shim-under lifters, all the same size and close to what was needed.

That sounds like a good plan - so where did you get them from and what size did you order? (I'm unsure how to know what is close to what was needed)

[manga_blue]

OK, I just spoke with my engine builder about this.

Being the proprietor of a shop, when he's working on a head, he has various lash caps laying around that he uses for reference to measure lash and then order the needed size caps.

If you're attempting to do this job yourself, as you suggested, you'd need at least one lash cap as a reference because feeler gauges aren't thick enough.

I carry Supertech lash caps which are available in 10 thicknesses from 1.90mm to 3.60mm.

My builder said that if you ordered one cap, go with a thinner one that would allow you room to fit a feeler gauge, perhaps a 2.5mm thick one.

In summary, unless you have access to a machine shop who has a selection of lash caps to quickly determine what size(s) you'll need to set up the head, you'll have to go through the process of ordering a set of (16) lifters and one lash cap as a reference, then you'll have to go through the tedious process of test fitting the lash cap 16 times until you determine the ideal thickness cap needed for each valve, then ordering from me (or elsewhere) the needed caps before you can assemble the head.

Let me know if the above makes sense and if I can help you any further.

It turned out that 2.5mm was pretty much what the doctor ordered and Bill sent me a cheap set of 8 with the lifters. I still have those. If the size is in the ballpark for your cams then I'd be happy to lend them.

[gslender]

Having a lot of hassles with the shims for the SUB and the new cams.

Working with Precision Shims in VIC, but about to pull the trigger on my 3rd shipment of shims !!

Problems ranging from a) initial gaps too big or not existing at all and so finding it difficult to accurately baseline the shim sizes, and b) Precision Shims isn't being that Precision and sending me shims that are out by .15 mm at times !!!

Does anyone know of a local Brisbane shim engineering shop that either sell or make shims to fit?

I'm looking for 6mm OD shims, 5.6mm ID and 3mm depth hole - in sizes from 4mm to 5mm in .04 mm increments etc.

Man this is taking way longer than expected!

G

[tbro]

Mate,
I think your doing something wrong, Precision only goes on what YOU ask for.

Borrow/steal beg or buy a set of shim over buckets, measure each shim with digital verniers, write the measurement on the face with a permanent marker.
measure each bucket, the contact surface to the valves and the contact surface to the shim, fit the shims and buckets into the head and fit cams, making sure everything is CLEAN and journals are oiled.
Grab a set of feeler gauges (I use straight ones) and start by going too big and come down 1 feeler at a time until you can "just" slide them under the cam.
Measure the thickness of the feelers and then add up the figures that are on the feelers to make sure everything is right.
Right it down on a BIG piece of cardboard with the corresponding lobe and write the thickness of the Mazda shim, the thickness of the feeler gauges
and subtract the running clearance, do that with ever lobe and Bobs your uncle.

It does take some time but if you do it correctly it will work out properly OR you can do what I and GS decided was the best way and that is do the above
order the valve caps in the thickness to give you the correct clearance, fit them and if you have to do any future adjustments then you can use std Mazda shims.
If your not reving past 8000rpm by a real tacho you won't have any problems at least I havn't on the dyno @ 8500 on a couple of pulls.

What clearance are you running as a matter of interest as you should run what the grinder has ground them for.

Have you thought about how your going to dial in the cams as you don't have the valve opening degrees it might be better off taking them to Tighe and have them
procam the cams to give you the specs with openings and centers etc.
Just a thought!!!

T

[Magpie]

G you have just over 4 weeks before Morgan Park to finish, tune and run in, you can do it!

[gslender]

I think your doing something wrong, Precision only goes on what YOU ask for.

Well, I've definitely received incorrectly measured shims from them. I'm using a very precise digital micrometer with 0.001mm precision and they've been out a few times with the shims they've sent me. This can happen and they are only human and can mislabel bags and/or get muddled up.

I've done this a few times and I'm fine with the process. The challenges are that I'm way, way out with these cams due to the significant change in base circle diam. This means I'm buying 5mm shims instead of the normal 3mm shims, and that in itself is proving a challenge.

I'll get there - just been really annoying as the parts aren't easy to swap and test if you're waiting on shipping from VIC. First batch the hole depth wasn't what I asked for as the SuperTech valve retainers reduce the valve stem length to < 2.5mm and when you're adding 5mm on top, that approach isn't going to work reliably. So we swapped to putting the shim upside down in the bucket stem, and then that means the shim ID changed from 6mm to 5.6mm and again, we had a few problems finding the spare shims in the sizes I need.

Overall a pain in the a$$$ process that when working with a single supplier over 2,000 klms away isn't the easiest... but that's race car for ya!

G

[gslender]

G you have just over 4 weeks before Morgan Park to finish, tune and run in, you can do it!

No need to run in. Just tune and go. Engine is already run in.

If everything goes right, I'll be ready. But I've said that before!

G