Quick question, hopefully this weekend to have an answer.

[vanagonturbo]

Update: Talked to Giles and he advised sending the pump back so he could work some more magic. No problem there. So in the meantime, I decided I would use a more appropriately sized turbo and put another pump on it. Here are the details, and the results:

Temporary pump has the following done:

Gov mod
Star wheel screwed down
max fuel screw cranked up to the point at which it does not hang idle
residual fuel screw cranked down to match max fuel screw
rotated LDA diaphragm to steepest ramp
GTD injectors are back in

I also replaced the turbo with a GT2056.

Result: runs much better and is more drivable. however, boost is still a problem. Smoke is not a problem. at about 2500 at WOT I see 8psi. @5500 rpm, I see 18ish PSI.

I am beginning to suspect the head. It is new but not OEM. I got it from Overland and it has no OE casting marks. It looks very similar to a head we had at the shop recently from Overland that had the cam bore machined too high with respect to the deck surface. I am thinking that the lift is not enough to create enough flow to spool the turbo properly.

Anyone have any more input? I am really disappointed. I have about $100 in mods on my Golf 2 GTD and it would stomp the Scirocco which has about $3k in mods...

[R.O.R-2.0]

gasser turbos do NOT spool right on a diesel..

i dont have the reason as to why, but i know it usually doesnt work out..

is the GT20 off a gasser too?

[vanagonturbo]

The GT20 is a new unit and as per specs it should work excellent for this application. I agree that gasser turbos may not work as well as a turbo configured for a diesel application. However, a turbo is a turbo and it does not care what type of fuel is being used. It comes down to the specs of the turbo.

Even considering the results of the GT25R that was on there previously, I think I should have had better results. Not sure if it was a pump problem or not; considering the pump was a problem to begin with.

I even ran it with no air cleaner or intake this morning just to verify it was not an intake restriction. I must admit that I did not calculate pleat dimensions when I used the air cleaner that I have. Either way, the intake is not the problem.

Thanks for the feedback! :beer:

[R.O.R-2.0]

then the pump is pretty much the only other reason behind the situation..

[vanagonturbo]

Please read my update. the pump has been swapped. I have taken it apart and resealed the whole thing (it was a used leaky pump that worked fine on another car).

[vanagonturbo]

Ok, I did a compression test today. 275psi in all cylinders this test was done with the engine warm. I did some reading here and it appears that low compression can be a result of using the AAZ head. However, this seems pretty low for even that. Keep in mind that the engine only has around 600 miles on a new rebuild.

I read some about advancing the timing, but, if I pull the advance arm on the pump, it gets pretty clacky. I figure if I advance more timing it would be pretty loud. Pump is set to .95 right now.

This may be sort of irrelevant, but I timed the previous pump by ear during my trials. Then I checked it with the gauge just to see where it was at and it was about .98.

Any more ideas? This is really frustrating to have put so much time and effort into this build and have it be significantly slower than the previous engine.

FWIW, the previous engine was an NA 11mm block, AAZ HG, TT downpipe to 2.25" muffled exhaust, blocked of wastegate, blocked off DV, factory T3 turbo, terrible intercooler piping, and basic pump mods.

Oh one last thing regarding the head. I had another new AAZ head on the shelf so I measured the cam lobes and the deck height from the lowest point on the cam bore to the deck surface. Both cam and deck distance measured the same. I have not taken the head off yet...

Sorry to edit so much, but I thought it might be prudent to note that the HG is a metal AAZ gasket, 2 notch.

[R.O.R-2.0]

Ok, I did a compression test today. 275psi in all cylinders this test was done with the engine warm. I did some reading here and it appears that low compression can be a result of using the AAZ head. However, this seems pretty low for even that. Keep in mind that the engine only has around 600 miles on a new rebuild.

I read some about advancing the timing, but, if I pull the advance arm on the pump, it gets pretty clacky. I figure if I advance more timing it would be pretty loud. Pump is set to .95 right now.

This may be sort of irrelevant, but I timed the previous pump by ear during my trials. Then I checked it with the gauge just to see where it was at and it was about .98.

Any more ideas? This is really frustrating to have put so much time and effort into this build and have it be significantly slower than the previous engine.

FWIW, the previous engine was an NA 11mm block, AAZ HG, TT downpipe to 2.25" muffled exhaust, blocked of wastegate, blocked off DV, factory T3 turbo, terrible intercooler piping, and basic pump mods.

Oh one last thing regarding the head. I had another new AAZ head on the shelf so I measured the cam lobes and the deck height from the lowest point on the cam bore to the deck surface. Both cam and deck distance measured the same. I have not taken the head off yet...

Sorry to edit so much, but I thought it might be prudent to note that the HG is a metal AAZ gasket, 2 notch.

Smokey Eddy ran like 1.25mm advance in his 1.6/1.9 half breed.. idk why, but they need more timing to run right..

and 275 psi sounds way low.. should be almost 500..

[8v-of-fury]

will it still have 500psi on a fresh rebuild and being that it is a half-breed?

[vanagonturbo]

Yeah I read that about Smokey Eddy. However, in other posts, I have seen people setting the timing anywhere from .95-1.05mm.

I am aware that because I am using the AAZ head that the precups are larger and thus will make the compression lower. I have not done a leak down test as I need to make an adapter. I do agree that a strong stock engine should have between 475 and 500psi in all cylinders, but this engine is not in a stock configuration, so I expect that the numbers will be a bit lower. 275 seems way too low though. I guess I will know more when I do the leak down test. I am still suspecting the head as the bottom end is 3rd overbore, new pistons, ceramic coated crowns, moly coated skirts, and total seal rings.

Any other things that I should be looking at? I think part of the problem has been narrowed down to the low compression numbers..

[R.O.R-2.0]

a normal vw idi diesel is about 24:1 compression.. a hybrid is like 18-20:1 iirc..

[8v-of-fury]

I think it was figured that the hybrid motors actually have something like 17.5:1 CR.. Thus the reason not many cold climate people do this swap. Lowering to 17,18 hell even 19 compression when its designed for 23.5:1 your gonna get really low numbers... Plus your still very fresh on a rebuild, do rings fully seat in 600miles

[R.O.R-2.0]

I think it was figured that the hybrid motors actually have something like 17.5:1 CR.. Thus the reason not many cold climate people do this swap. Lowering to 17,18 hell even 19 compression when its designed for 23.5:1 your gonna get really low numbers... Plus your still very fresh on a rebuild, do rings fully seat in 600miles

i doubt rings seat in 600 mi.. unless he was absolutely railed down, piss tight to the bolts, everywhere he went, the rings are NOT seated yet. but that doesnt explain compression thats 150 psi low..

275 psi compression is like 14-15:1 rough guestimate..

[vanagonturbo]

I totally havent been back to this thread as I thought that ROR was the last poster from before! Lol!

I have not been flogging the crap out of it, jsut a few WOT pulls. Mainly jsut commuting varying speed and such. I do not think the rings are broken in yet either. However, I do think the low comp numbers are something that needs to be addressed first.

just for the hell of it, yesterday, I went out to my TDI Vanagon and comp tested it. I just wanted to make sure there wasnt a problem with my guage. The TDI comped out at about 400 on a cold engine @25°F ambient temps. I could not do a hot test as the van wouldnt start 

I think the next step is to pull the head and see what I find. I dont really see any need to build a leakdown tester for it at this time as no matter what I find, I will still need to pull the head..

unless someone else has some magic?

[vanagonturbo]

Ok, update. Yeah I know, longest troubleshooting procedure evar!

I built a leakdown tester today and checked it. no leakage at the valves. very minimal crankcase leakage. So I decided to check the cam against a few others that I had lying around. Open and start of open of the valves @BDC are the same from a visual inspection between the OE 1.9l head and the 1.6l head. however, both heads have been sitting so I doubt the lifters are primed. that said, the valves do not open on the heads that I looked at while checking overlap. I thought maybe overlap could be a problem...

I have checked the cam/crank timing 3 times. I even used a small screwdriver in the injector hole to verify my marks are correct and they are.

I think at this point, I have no other option but to pull the head and see what is going on in there that I cant see.

Any other ideas?

Oh yeah, I might also note that I have a two notch AAZ HG.. I see in ETKA that there is a 1 notch...

[vanagonturbo]

Ok, pulled the head today. Nothing looks amiss. checked piston protrusion. Its about .63mm. Seems a little low if you ask me after I looked at the specs for the various HG options. It appears that the one notch (NLA) for an AAZ STARTS at .66mm. Does anyone think this is the problem combined with the larger precups?

I will see if I can get a syringe this week and CC the precups on this head vs. the other AAZ head I have and compare that to the stock 1.6l head.

FWIW, the crank is the same crank that was in the block when it ran before. the only thing that was changed with regard to this protrusion situation are the pistons.