ALFAGTV6.COM

The diff is open and not strong and i'm told the ring and pinion are also weaker due to their size.

Questions for Alan, or anyone out there, about lifter/tappet for the 24v.

Are they identical to the 16V lifters? Some of my lifters have discolored a bit, probably due to a little but of surface corrosion, but I cleaned them up.

Or what is the proper way to refurbish them? They need to be slightly dished? The slightly part sounds a potentially inaccurate process of making them "accurate".

I can get TS 16V lifters for cheap, hence the question. 24v lifters are UKP18.50 each. 24 X 18.5 = 444. Robbery.

I know that 33 16V has the same lifters, but not sure about 2.0 engines.

I read a little about total seal rings, should i try them? All of you that use them, did you change all three or just top?

Maybe any specs for the top one on 24V, which one is the most apropriate?

Thanks.

I'll go for goetze rings, no real advantage in total seal as i read on few forums...

Making bob weights (part one)






Main pulley undersized (lighter 600 grams and smaller 8%)






main vs water pump pulley

Finnaly weighted all pieces and calculated bob weights...

Jim i assume you weighted big ends and then calculated small end weight? Because i get same numbers that way (within 1-2 grams) but if i weight small end it's around 179-180g and not 184g like if calculated...
I guess that is up to some friction betwen materials when weighting the rods in parallel. I calculated that even if i use my numbers it wouldnt make such a big difference as it would be like 50% factor (i'm using 51%)

My bob weights will be 880g (a little lighter pistons than in your book)

Some pics:

small end weighting (i then weighted big ends too and numbers were around 438g)




Lightest and heaviest conrod (suprised how accurate they are from factory!)



lithle grind off the big ends to get them all in less than a gram...



pistons



difference is big here (because they are from 2 used engines - same B class ofcourse)



after a lot of grinding it's there



All calculations

Let me note the place you removed weight from the pistons underneath the pin boss is the absolute WORST place you could choose! That area is what keeps the piston from flying off during the exhaust stroke when it also exerts the maximum tension on the rod!
Additionally, what I see in the picture is the wrong way to suspend a rod big end for weighing. See V6 book, pp68, bottom left pic. Its small but you can clearly see the suspending arrangement for both big and small ends, which have small bearings (~12mm diameter) in the middle and are held by articulated levers (also with small bearings.
You weigh each end in the way shown and you use that weight for the calculation. Actual total rod weight is not used in calculating bobweights however, all rods must of course weigh exactly the same. Arriving at equal end weights between rods is not easy as you have probably seen. First you equalize small/big end weights and then you adjust total weight from the beam. And please grind away those block lumps from each end, they are not needed!
Jim K.

Thanks for that. Well about piston grinding, i saw it on some videos that they grind away at that place... I didnt grind much and i found out that the lightest pistons are a little thinner right in that area (from my second engine). I'm still learning things...
About rod weighting, i changed the method after that pic, i used a bearing too, and weighted all rods 3 times on each end and on two different scales. I got repeatable number within 1 gram so i think it's ok.
So you say i should go all the way with rods and grind blocks to lighten them? Hmm maybe

About pistons lightening, you take away material inside the crown?

You don't have to touch the piston alloy at all. All required weight can be removed in a lathe or with a Dremel hand-grinder from the inside edge if the piston pin by grinding at ~45* angle. Steel has much higher specific weight than the piston alloy so you grind away much less volume.
Jim K.

Haha i know and it's written in the book too. i just forogot lol. Well i grind the pins on others and it's allreally nice now. you can see the numbers it's all in 0.1g!



I washed all pistons and pins in soapy water



Weighted all again today and final bobweight number is 881g

Cutting in half



They are 870g + cable ties 11g




Then i tried flexhone tool on an old very poor liner




2 times 15sec right and left rotation and it's really nice even on poor liner

Liners in factory tolerances, almost no ovality (still i'm gonna align the widest part with crank)




Bobweights done all insde 0,2g! (with cable ties ofcourse)

Going to the balancer today

Lovely, I can't wait for my big heavy package from Greece!!!!

BTW, how much lift does your AHM cams have? Can you put it on a cam doctor and give some info on the curve? After much discussion with JK, we are down to ...... very low 10.2mm lift! I am afraid to bring the topic up with him again because it might drop down to 9.X .

It started out at a lofty 11.Xmm . I was very happy then.

Although I could still go with 11.Xmm cams but risk wrecking the lifter/cams. We decided on something that would not cause any catastrophic failure.

Coward....

You all going crazy with lift? Why? What's wrong with 10mm? Both the 3liter and the GTA have 9.3mm, the GTA having a bit more duration. By regrinding either cam, the best you can end up with is 10mm and 226* @ 1.25mm, while the GTA has 220*, the 3liter 208*, my Williams 222*. Therefore, 10mm and 226* @ 1.25mm has to be a hell of a cam! You want better? Go pay 1300€ !!
Ok, here's the magic Cam-Doctor screen shot for you guys. Inner red is std 3liter, next is GTA (notice flat nose), blue is my Williams and the black is the most you can get out of the 3liter without excessively decreasing the base circle -in which case you have follower problems.
Jim K.

So when you say "risk of breaking cams/lobes" are you talking about reducing base circle? What about keeping base and go larger?
Yeah, sure, you probably need to make room for it but then again, it wouldn't be the first time...