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Author Topic: 81 Rabbit LS AAZ (2023: now tdi-m)  (Read 37519 times)

Reply #105August 21, 2017, 08:13:00 am

RabbitJockey

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Re: 81 Rabbit LS AAZ
« Reply #105 on: August 21, 2017, 08:13:00 am »
I haven't covered much of what i've done in the last year, but the engine skipped time, so i rebuilt the head and changed some seals in the pump and had it running for about a month then i was driving it very spiritedly and had a bit of a run away, it shut down pretty quickly but the damage was done. I had known the bottom end was a bit worn making this a possibility, but i decided to run 30psi anyway so this is the result haha. I need to take a break from it now and finish some other projects before i come back to this and either go to over sized pistons or swap to an ahu engine i have.
01 Jetta TDI 100% stock daily
81 Rabbit:TDI-M ported head, Frank06 cam, PD intake, hybrid T3 turbo, Renault intercooler, Syl20 11mm pump, light weight fw, and yellow California Clutch clutch kit

Reply #106August 21, 2017, 09:00:30 am

RabbitJockey

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Re: 81 Rabbit LS AAZ
« Reply #106 on: August 21, 2017, 09:00:30 am »
i am just hoping the head is ok, i haven't removed it yet, but i did a compression test and the results were 0-220-150-220 so i know something is definitely very bad.  I used an endoscope camera to view inside and the pistons look ok so thats a decent sign.
01 Jetta TDI 100% stock daily
81 Rabbit:TDI-M ported head, Frank06 cam, PD intake, hybrid T3 turbo, Renault intercooler, Syl20 11mm pump, light weight fw, and yellow California Clutch clutch kit

Reply #107September 13, 2021, 09:08:09 am

RabbitJockey

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Re: 81 Rabbit LS AAZ
« Reply #107 on: September 13, 2021, 09:08:09 am »
It's been a long time, but today I was thinking about the missing low rpm power I had with this engine. Since then I've read that you should apply 12v to the solenoid on the front of the pump's advance piston cover. Well, I had applied this voltage, and now wonder if that could have been the issue,

It still may have been an issue with the turbo. We'll know soon because I've been putting together an m-TDI for this car over the past few years and I'll be using the same turbo.
« Last Edit: September 13, 2021, 10:34:22 pm by ORCoaster »
01 Jetta TDI 100% stock daily
81 Rabbit:TDI-M ported head, Frank06 cam, PD intake, hybrid T3 turbo, Renault intercooler, Syl20 11mm pump, light weight fw, and yellow California Clutch clutch kit

Reply #108September 13, 2021, 10:36:16 pm

ORCoaster

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Re: 81 Rabbit LS AAZ
« Reply #108 on: September 13, 2021, 10:36:16 pm »
Is the 12 VDC applied to the advance piston only when cold to help it start?  Not during normal running and warm temps.  Just asking as I don't have that engine knowledge.  Just thinking out loud I guess.

Reply #109September 14, 2021, 09:17:24 am

RabbitJockey

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Re: 81 Rabbit LS AAZ
« Reply #109 on: September 14, 2021, 09:17:24 am »
with the boost controller creeping to nearly 20psi (however temps never over 25psi) and also EGTs which will exceed 1300 degrees on a long I went and did a few dynos, I'm still getting used to the Gtech, I don't like this unit, it does not do a very good job at scaling RPMs, but it says even with the RPMs of the peak hp rating will be correct... I'm guessing the torque numbers are what suffer.  so this run had a peak hp of 130whp @4340, and a peak torque of 160ftlbs@4287, there were 2 other runs that I would consider close to accurate, one was 122whp & 140tq, and the other 133whp & 180tq.  these runs were done on the same road in different directions or whatever.

All of the dyno graphs are shaped like this one with a huge dip in power between 3-4000 RPMs, I'm not sure what the issue is, I think it's fueling or something because there's definitely a dead spot in acceleration then the turbo lights off and goes from 10-20psi instantly and pulls hard to 4500-5k.  but I have a few things I'm going to check before I speculate and gripe too much on here.



I had 12v applied to it all the time, running straight off of the fuel stop solenoid, there was this drop in mid-range power and then the rapid gain.

im still not sure if it was the pump or the turbo, either a stuck wastegate or compressor surge. We will have a better idea once I get the new engine running but the new engine is pretty different because it will have a PD intake, 7mm valve stems, head porting, SDI camshaft, and an intercooler. plus it's a TDI so it's not an apples to apples comparison
« Last Edit: September 14, 2021, 10:26:17 pm by ORCoaster »
01 Jetta TDI 100% stock daily
81 Rabbit:TDI-M ported head, Frank06 cam, PD intake, hybrid T3 turbo, Renault intercooler, Syl20 11mm pump, light weight fw, and yellow California Clutch clutch kit

Reply #110December 04, 2023, 08:02:11 am

RabbitJockey

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Re: 81 Rabbit LS AAZ
« Reply #110 on: December 04, 2023, 08:02:11 am »
What I've been doing the last few years



« Last Edit: December 04, 2023, 08:48:55 am by RabbitJockey »
01 Jetta TDI 100% stock daily
81 Rabbit:TDI-M ported head, Frank06 cam, PD intake, hybrid T3 turbo, Renault intercooler, Syl20 11mm pump, light weight fw, and yellow California Clutch clutch kit

Reply #111December 06, 2023, 03:38:48 pm

RustyCaddy

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Re: 81 Rabbit LS AAZ (2023: now tdi-m)
« Reply #111 on: December 06, 2023, 03:38:48 pm »
That's really great.  Have you switched to a 1Z motor? Or a hybrid? Something else?

Reply #112December 06, 2023, 06:10:28 pm

RabbitJockey

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Re: 81 Rabbit LS AAZ (2023: now tdi-m)
« Reply #112 on: December 06, 2023, 06:10:28 pm »
Hi, this is an AHU tdi. I bought a year or 2 before i killed the aaz, because i had little faith in myself or that engine haha. It has the same turbo as the last engine, and a few more upgrades, some of which were originally destined for the aaz before its compression dropped to zero.

i've been working on gathering up all my photos from this build and swap. It's been over the course of the last 5 years that i've put this together so the photos are on a few different phones.

I'll make a more detailed post soon. I miss the old forum days, its so much more organized and even acts as an online journal, it's a shame that fb has robbed most traffic, and photobucket has robbed many photos.
01 Jetta TDI 100% stock daily
81 Rabbit:TDI-M ported head, Frank06 cam, PD intake, hybrid T3 turbo, Renault intercooler, Syl20 11mm pump, light weight fw, and yellow California Clutch clutch kit

Reply #113December 06, 2023, 07:20:46 pm

libbydiesel

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Re: 81 Rabbit LS AAZ (2023: now tdi-m)
« Reply #113 on: December 06, 2023, 07:20:46 pm »
Looks good.  M-TDI FTW! 

Reply #114December 12, 2023, 08:15:14 pm

RabbitJockey

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Re: 81 Rabbit LS AAZ (2023: now tdi-m)
« Reply #114 on: December 12, 2023, 08:15:14 pm »
I still plan to make a "mega post" to get everyone caught up ok the rest of what I've been up to with this car.

But for now we have the present.

I had been hoping to try to start this new engine this past weekend but I was having trouble getting it timed right.

Sylvain who built the pump told me to time it to 0.90mm and that I should be able to time it just like my old engines. When I timed it up the lowest I could get with the pump fully retarded was 1.20mm. So I tool the belt on and off a few times being meticulous to make sure I had the belt on perfectly.

The issue turned out to be that even though this pump was brand new from Sylvain it had sat for nearly 3 years and the advance piston was stuck. The solution was to remove the pump remove the advance piston covers and clean it out and get the pump moving again with lots of oil and seafood deep creep.









And as a little homage to the old yellow dot pumps I painted the advance cover yellow.

I filled the pump with diesel purge and I will let it sit like this for a few days until I have time to get to it again.
« Last Edit: December 12, 2023, 08:31:40 pm by RabbitJockey »
01 Jetta TDI 100% stock daily
81 Rabbit:TDI-M ported head, Frank06 cam, PD intake, hybrid T3 turbo, Renault intercooler, Syl20 11mm pump, light weight fw, and yellow California Clutch clutch kit

Reply #115December 12, 2023, 11:14:07 pm

ORCoaster

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Re: 81 Rabbit LS AAZ (2023: now tdi-m)
« Reply #115 on: December 12, 2023, 11:14:07 pm »
Nice that you found the problem.  It would have been a bummer to have moved the belt a notch or two to get it at the 90 mm setting only to have the piston free up and drop your timing way back and possibly cause performance issues.

How did you ever chance upon the piston sticking?  No response from the cold start cable? 

Reply #116December 13, 2023, 07:25:17 am

RabbitJockey

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Re: 81 Rabbit LS AAZ (2023: now tdi-m)
« Reply #116 on: December 13, 2023, 07:25:17 am »
this pump doesn't have a cold start on it.

If I wasn't working with Sylvain i probably would have tried to start it with the pump retarded like you said. Before i removed the pump i did try cranking it over with the starter for 30-60seconds with 15-20 minute breaks in between and the piston never moved.

Sylvain was 100% certain that I should be able to time the pump like normal, and after reinstalling the belt 3 times, and then installing it 1 tooth off i was 100% certain that i was doing it right, so it had to be the advance piston.
« Last Edit: December 13, 2023, 11:52:15 am by RabbitJockey »
01 Jetta TDI 100% stock daily
81 Rabbit:TDI-M ported head, Frank06 cam, PD intake, hybrid T3 turbo, Renault intercooler, Syl20 11mm pump, light weight fw, and yellow California Clutch clutch kit

Reply #117January 02, 2024, 08:39:16 pm

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Re: 81 Rabbit LS AAZ (2023: now tdi-m)
« Reply #117 on: January 02, 2024, 08:39:16 pm »
So the old engine, I had run way too hot the egt gauge looked like this  :o :o :o :o :o

the first picture is a good spare AAZ head that I have, and how it looks without a prechamber installed:




and next is my overheated AAZ head. I think part of the issue is that the engine ran away but i will admit that i also ran the engine much hotter than i should have, allowing it to reach over 1600* degrees with no intercooler. With a stock cranked pump that might be fine, but with a giles pump that delivers full fueling and timing advance it is definitely not fine. Before i even pulled the head i knew it was bad because when i removed the injector the injector hole and heatshield were completely covered in a wall of aluminum slag. the tips of all the glow plugs were burnt off.


01 Jetta TDI 100% stock daily
81 Rabbit:TDI-M ported head, Frank06 cam, PD intake, hybrid T3 turbo, Renault intercooler, Syl20 11mm pump, light weight fw, and yellow California Clutch clutch kit

Reply #118January 02, 2024, 10:45:13 pm

ORCoaster

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Re: 81 Rabbit LS AAZ (2023: now tdi-m)
« Reply #118 on: January 02, 2024, 10:45:13 pm »
CAR ABUSE.  For Shame

Reply #119January 03, 2024, 08:57:24 pm

RabbitJockey

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Re: 81 Rabbit LS AAZ (2023: now tdi-m)
« Reply #119 on: January 03, 2024, 08:57:24 pm »
With the old aaz engine i knew that it was running too hot, and i was also having issues with losing power at high boost and low rpms. I believe the low rpm dip in power was caused by turbo compressor surge. Back when brexit was first enacted the british pound really took a dive so i bought a pd intake off of ebay.co.uk for cheap, i think it was less than 60usd shipped to my door, and it had been cleaned. So that should help to reduce compressor surge by increasing flow.

Then i bought an aftermarket toyota mr2 intercooler, to help lower my egt's and also improve flow which would also help to reduce compressor surge.

Unfortunately this engine had met its melty demise before i installed these parts. which is funny because they would have helped to prevent it.

PD intake after i did some light porting/port matching




me test fitting the mr2 intercooler with a 1g dodge neon non-ac radiator



and here you can see the mr2 intercooler was a tight squeeze with the mk1 starter. a mk2 starter did create more room but ultimately i decided to swap to a renault double pass intercooler for easier fitment and plumbing. A single pass intercooler like the mr2 unit flows better and works better but i figured on an engine that is less than 200hp it will be sufficient, while also solving a few headaches. Although I may revisit the mr2 intercooler I think it could be made to fit.


01 Jetta TDI 100% stock daily
81 Rabbit:TDI-M ported head, Frank06 cam, PD intake, hybrid T3 turbo, Renault intercooler, Syl20 11mm pump, light weight fw, and yellow California Clutch clutch kit

 

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