Engine Reassembly

[jimnielsen]

Calder testing went well - did more than 100km on the track.... That should have bedded the rings in! Collected a mountain of data and video - but the summary is that we got it to run at about 12.7:1 AFR WOT - reasonably flat across the rev range. This is hard when you are still using the breakpoints in the original maps (but with different values in the tables..) Too much of the air density breakpoints are outside the range of where the car is driven (on the track). The new turbo went well - I toned down the overboost map but it still was making 1.25bar in 5th at 6000 RPM and 208kph. It was quite a cool day (15 c). Was not able to get the coolant over 70 c. This could prove a problem.

had a small boost leak, a small coolant leak and a problem with the center driveshaft bearing - but all in all - a great day!

Car even did its fastest time at this track - at < 80% effort.

data and video to follow..

This is the cars first and last run on pump gasoline - I am going to convert it to E85 in a week or so - then back to Calder for another mapping exercise - then finally to a dyno for a more precise calibration. And that that - well thats the plan..

thanks to everyone who came to help out on the day!

[AlfaJack]

Nice one Jim.

Strange how your coolant only went up to 70. That new rad and pump must be very very efficient!

Looking forward to the videos!

[Juan AR155Q4]

Are you still using the oem thermostat?

[1NRO]

Sound most excellent Jim, for sure the rings are snug now.

How might you compare the response of the car now to how it used to be?

I must say the thought of the fuel change has me waiting most keenly. Do they tamper with the blend much over there?

The ebay turbo has lasted longer than some would have you believe! Had a waggle of it? I'm thinking you need to be saving some pennies for a fancy turbo though, something like a GT30 will fly.

Nik

[jimnielsen]

.. I am not using the a thermostat at all. you cant really use the original Q4 one with an electric water pump - as it also controls the bypass water flow in a way that does not work so well for these pumps. I am using an old thermostat of Wrinx's with the thermostat 'bits' cut out. I may need to buy the electronic controller for the water pump that uses the water temp to control the impeller velocity. It was a cold day...and i was not driving the car very hard at all. A warmer day and 100% effort would (I think..) bring the temp into the 90 degree range.

..The car has much better response now, actually - even with limited pressing on the pedal, especially limited in 2nd gear, as I was making sure to keep the revs down to ~ 6k. I am planning on running it to 7.5k in future.

I am going to be using 'race E85' which is simply a blend of 15% 98 Octane ULP (RON) and Ethanol from sugar cane that is made locally. Its guaranteed to be E85 - no more and no less.

I will check for turbo bearing wobble when I get a chance to go over the car next week. If nothing else, the Chinese turbo should provide a good baseline for what trim of turbo is required.

[1NRO]

So a nice responsive engine to date, excellent. How are your det detection systems performing? Much det count?

[jimnielsen]

Here is a snapshot of the data from my first tests. Fuel is still 'somewhat' rich. The temp reading is from the 'pre intercooler' sensor. The post one is acting up a little. I have the data from it, but the calibration needs work.

[wrinx]

Interesting stuff!

Are the boost readings right, looks like you're only getting boost over 4000revs?

wrinx

[jimnielsen]

yes, they are right - I plan on getting about 1.4 bar all the way to 7500 RPM. Early indications are that this will be easily achieved with the T3/T4 turbo. perhaps even more interesting is this graph that compares temperatures from the pre-intercooler side of the system to the post-intercooler side (inlet manifold). As you can see the intercooler acts as a heat sink quite well. I am using identical bosch AT sensors. One is in the inlet manifold its self - the other is just prior to entering the intercooler (after the turbo).

The Y axis is temperature in Degrees c - the X axis is time.

Also - does anybody know where I can buy a new 'centre bearing assembly' - Are they still available as a new alfa part?

[wrinx]

I plan on getting about 1.4 bar all the way to 7500 RPM.

That's what I would want, makes sense imho

wrinx

[na15575]

no jim there isnt available as a new alfa part

it is the same with Lancias but i cant find it in any place

[Gery83]

no jim there isnt available as a new alfa part

it is the same with Lancias but i cant find it in any place

The bearing's part number is the following:

KOYO 62052Rsc3.FGGA2

[jimnielsen]

well.. this could be a 'problem' then. Gery.. is that part # JUST for the bearing and not the rubber bit/

jim ~

[Gery83]

well.. this could be a 'problem' then. Gery.. is that part # JUST for the bearing and not the rubber bit/

jim ~

Yes!

It is impossible to get a new one.
You need a new bearing. And a bushing specialist to put the new bearing into the old 'case' and fill it up with rubber...

[mindus]

If your bearing is ok and only a rubber part is worn, then you might want to 'replace' that rubber with custom one (e.g. with something like 'glue' for front window)..

[Gery83]

If your bearing is ok and only a rubber part is worn, then you might want to 'replace' that rubber with custom one (e.g. with something like 'glue' for front window)..

Just forget it...
That is the McGyver way of things...
There are specialists for such jobs, you don't want to mess with something that important in the drivetrain...

[Evodelta]

no jim there isnt available as a new alfa part

it is the same with Lancias but i cant find it in any place

I don't think it is, it looks different to me in the picture and the Lancia integrale one is made by SKF.
Still no longer available though.......

[SteveNZ]

Its hard to tell the condition of the hanger bearing there from the photo. Howevver they all usually have a bit of movement up and down. If the bearing is ok and its still solidly mounted to the hanger (not seperated completely) I would not be too concerned.

It will be interesting to see the temperature curve pre intercooler at different boost and RPM etc. It will give a good indication to the efficiency of that turbo. A pressure sensor in the ex manifold would be good to have.

[jimnielsen]

In the manual - it shows that the universal joint is held in by circlips...no such luck with mine, I am afraid. So I won't be able to remove it and replace the center bearing.

I am going to have to simply strengthen the rubber surround with urethane (this is quite common practice on 116 type alfas.. and I did it on my last race car.)

As far as center bearings go - there are a lot of 25mm inside dia. center bearings that would work fine on the Q4. Mazda make one for the B2000 van that I think would fit fine with the simplest of tweaks. But - as you can see - I am not going to get to test this.

jim ~

[jimnielsen]

Steve.. here is a graph that shows both of the temps (on the same scale). It show 3rd, 4th and 5th gears. Boost peaks at 1.27 bar at 5500 rpm in 5th @ 206 kph. Temp keeps rising for a further 4 seconds after throttle off. to 92 degrees. peak temp in the inlet manifold is 42 degrees. I am going to fit my waterspray kit - It will be interesting to see if it actually makes a difference - or its all just 'talk'..


cheers, jim ~

[wrinx]

In the manual - it shows that the universal joint is held in by circlips...

Has that been bodged by punching around the circumference or is it the factory solution?

wrinx

[wrinx]

Steve.. here is a graph that shows both of the temps (on the same scale). It show 3rd, 4th and 5th gears. Boost peaks at 1.27 bar at 5500 rpm in 5th @ 206 kph. Temp keeps rising for a further 4 seconds after throttle off. to 92 degrees. peak temp in the inlet manifold is 42 degrees. I am going to fit my waterspray kit - It will be interesting to see if it actually makes a difference - or its all just 'talk'..

I think you've become the forum test mule

wrinx

[Steve Webb]

Is it the autospeed waterspray kit? I fitted one of those onto the std intercooler: Waterspray install

[1NRO]

Just buy a new UJ, better to do that than try to reuse the one in there anyway. Use a die grinder with a sharp edged stone (re-dress when rounded) to grind away the staking and your good to press them out.

[SteveNZ]

I agree with 1NRO. Fit a new cross, you'll damage it pressing it out anyway. Hopefully there will be a slot so you can just fix it with clips next time. If not you'll have to peen the metal over like that. Make sure you dont get the shaft out of phase when you put it back together.