Will an AAZ Head Gasket on a 1.6 change compression?

[Turbofan]

Here's the scenario; I recently took apart my motor to replace the head gasket and repair a weld on my oil pan to solve my oil leaks on the car. While the heads were off, I put a little diesel in each of the cylinders to loosen up the crap on the tops of the pistons. After a couple hours, I realized all the diesel had leaked out of cylinder 1, so I filled it back up and of course it leaked out again after an hour or less (meanwhile, the other three retained diesel through the following day.
 Remembering that I had developed a cold start misfire during the winter months, I pulled that piston just to take a look at it. I brought it to my machinist who remarked the piston rings seemed weak based on the springiness (or lack thereof). So I bought a set of Goetze's, borrowed a brush research ball hone, and cleaned up the cylinders.
As I had it apart, I also opted for a set of ARP studs and a three notch AAZ head gasket (the motor had a three notch to begin with, and always ran strong). I also had my injector nozzles professionally replaced (with Bosch units). With the engine back together, I now have a misfire when under load when I first start the car, as well as a bit of smoke. If I drive it lightly, it dissipates within 20 seconds or so.
Is it possible that the increased displacement area for the 1.9 pistons could be causing this? I'm thinking probably not, and it's most likely a ring scenario where they aren't holding pressure like they should. Piston ring 2 on all pistons did seem about .015" bigger end gap than spec.
Thoughts anyone? Maybe the rings haven't bedded in yet after 350 miles or so?

[burn_your_money]

It will lower compression and mess with emissions and other things, but your problem is probably from the rings not being broken in yet.

[wolf_walker]

I can't remember if it was an AAZ part but I used a later MLS on my last 1.6 head gasket, I looked up the compressed thickness and it worked out notch for hole. Ran it 40k, good mpg, its still going back east. Everything I read at the time said it was acceptable and an upgrade.

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[Turbofan]

I know the thickness is the same, I was just curious how a gasket with a slightly larger bore would affect the compression. It's probably my rings not seating, at least I like that answer, since the fix is to put miles on the car. It seems to be running strong on the highway and for the first time in years it isn't leaking a bit of oil. I guess once the fall hits, I'll see how severe this problem is, and if it goes away (without me taking the motor apart again).

[theman53]

make sure to keep a load on your rings to seat them.

[libbydiesel]

I did the calcs and based on the added size of the bore holes, it will lower compression 3% or from 23:1 using the 1.6 gasket to 22.3:1 using the AAZ MLS gasket.  That is less than the difference of using the wrong thickness gasket and not enough to make any operational difference. 

[wolf_walker]

I love it when people do actual math, especially when it confirms my wild ass guess in the past. 

[fatmobile]

I now have a misfire when under load when I first start the car, as well as a bit of smoke. If I drive it lightly, it dissipates within 20 seconds or so.

 You might want to advance your timing a little. Are you using the cold start lever?
 and check your clear fuel lines for air at startup.

 Kind of on topic:
 Wondering if Andrew would calculate compression on the 1.7TD for me.
 80mm pistons, metal headgasket, hydrolic 1.6 TD head.
 Everything else 1.6 TD; block/crank/rods
 Also wondering about compression if I swap to a 1.9 head.

[745 turbogreasel]

I did the calcs and based on the added size of the bore holes, it will lower compression 3% or from 23:1 using the 1.6 gasket to 22.3:1 using the AAZ MLS gasket.  That is less than the difference of using the wrong thickness gasket and not enough to make any operational difference.  *

* Till the gap packs with soot, and it makes less difference.

[Turbofan]

I am using the cold start lever, and it surely makes a bit of a difference. It idles smooth and nice, it's just when it's under load that it hiccups. When I put it together, I set the timing to about 1.00 (actually .99 IIRC), so I think my timing is ok. Today, I was able to put away from the parking lot slowly without it acting up, granted I was barely giving it any throttle, and the cold start was pulled out all the way. Maybe it's getting better, maybe it's just me.

It's really weird having rebuilt injectors. I thought I wouldn't really be able to notice, but now what I realize is my car doesn't have a haze in the rear view anymore when I romp on it. I've lost what I called my "Fairfield county smokescreen". I guess I'll have to pump the fuel up again to lose angsty tailgaters.

I finally hooked up my EGT probe last week (pre turbo, of course), and I'm surprised at how easily I can hit 1200 F. I thought it would take much more than it does, and I don't even have a turbo pump or a gov mod. I really need to finish building my exhaust and hook up my intercooler!

[fatmobile]

I see; you have it set for a certain number so it must be right, ha.
 Sorry to laugh but you won't even try to advance it because a number told you everything must be OK.
 
 Cold start lever advances timing and helps some, EGTs get high to fast,..
 but everything must be OK because the number says so, ha.
 
 Try advancing your timing a little, if it's too noisey move it back.

[R.O.R-2.0]

I am using the cold start lever, and it surely makes a bit of a difference. It idles smooth and nice, it's just when it's under load that it hiccups. When I put it together, I set the timing to about 1.00 (actually .99 IIRC), so I think my timing is ok. Today, I was able to put away from the parking lot slowly without it acting up, granted I was barely giving it any throttle, and the cold start was pulled out all the way. Maybe it's getting better, maybe it's just me.

It's really weird having rebuilt injectors. I thought I wouldn't really be able to notice, but now what I realize is my car doesn't have a haze in the rear view anymore when I romp on it. I've lost what I called my "Fairfield county smokescreen". I guess I'll have to pump the fuel up again to lose angsty tailgaters.

I finally hooked up my EGT probe last week (pre turbo, of course), and I'm surprised at how easily I can hit 1200 F. I thought it would take much more than it does, and I don't even have a turbo pump or a gov mod. I really need to finish building my exhaust and hook up my intercooler!

thats why it gets hot.. n/a pumps are notoriously hot on the bottom end.. if you had the gov mod, so you could spin it up there, then it would run cooler because of the increased air volume being pumped thru the engine.

[Turbofan]

I guess that gives me a reason to use my injection pump gasket kit I bought from the place that rebuilt my injectors. Maybe I'll have time this week to pull my pump apart. What's the concensus on 1.6 cam plates vs 1.9 IDI cam plates? I though I read the 1.6 one was a little better, as the 1.9 is a little more aggressive and will float the plunger unless you replace the springs.
I've been running a 1.9 for a long time (actually never driven my car with the stock one), but I just found it recently. I wonder if there is a benefit to putting the stock one back in.

[theman53]

If it was the 1.9TD plate Giles says it is a better design than the 1.6. It is set for the dual stage injectors, but he told me they give a bonus to a 1.6 engine. The 1.9IDI pump was his favorite to build with.

[fatmobile]

I am using the cold start lever, and it surely makes a bit of a difference. It idles smooth and nice, it's just when it's under load that it hiccups. When I put it together, I set the timing to about 1.00 (actually .99 IIRC), so I think my timing is ok. Today, I was able to put away from the parking lot slowly without it acting up, granted I was barely giving it any throttle, and the cold start was pulled out all the way. Maybe it's getting better, maybe it's just me.

It's really weird having rebuilt injectors. I thought I wouldn't really be able to notice, but now what I realize is my car doesn't have a haze in the rear view anymore when I romp on it. I've lost what I called my "Fairfield county smokescreen". I guess I'll have to pump the fuel up again to lose angsty tailgaters.

I finally hooked up my EGT probe last week (pre turbo, of course), and I'm surprised at how easily I can hit 1200 F. I thought it would take much more than it does, and I don't even have a turbo pump or a gov mod. I really need to finish building my exhaust and hook up my intercooler!

thats why it gets hot.. n/a pumps are notoriously hot on the bottom end.. if you had the gov mod, so you could spin it up there, then it would run cooler because of the increased air volume being pumped thru the engine.

 Retarded timing will cause high EGTs too.