D-cappz
Veteran Member
- Joined
- Jul 10, 2013
- Location
- Victoria
- TDI
- 2003 Jetta ALH, 6 speed, 4motion, fully loaded, leather heated interior, sunroof, steering wheel controls. Over 420,000km
Hello tdi Club, Iv been trying to research this for a few days now. I can't find a perfect/reliable answer, and most of the threads are quite old.
I have done some engine mods to my car. The last Dyno I was pushing 181hp & 325 ft lbs.
I have got a head made with larger valves, Ported, dual valve springs, stage 2 colt cam, new lifters and some ARP headstuds that I am going to be installing really soon. But while I have the engine open I was thinking I should put new pistons, rods and rings in being that I want to push over 200+hp.
Here is my questions:
What pistons would work best for the ALH that are
A. Standard ALH size (I don't want to bore the block)
B. Same hight so I don't have to shave the block
C. Can handle the power I want to push
D. Let's just say a drop in piston.
E. OR stick with stock ALH pistons.
Should I make the piston valve reliefs larger?
My intake valves are 36.9mm I believe, and my exhaust valves are 33.5mm
I have a stock core piston someone gave to me, and it seems that the intake relief grooves are 38.2mm and the exhaust reliefs are around 33.88mm
What rods would be best for the ALH that
A. Can connect to the ALH crank
B. Can handle the power
C. Can handle any upgrade I throw at them in the future.
D. Will work with the piston upgrade
What kind of power are the stock pistons & rods good for?
Should I upgrade to a set of gapless rings or standard?
Example of gapless is something like total deal or sealed power oil control.
If you have a List of parts I should get while doing this job, that would be great.
I came accross alot of Ppl suggesting to put ASV pistons in, and that they work. But I came accross this forum:
http://forums.tdiclub.com/showthread.php?t=443136&highlight=Alh+piston+upgrade
Let's stay on topic as alot of these forums I read seem to get lost.
Please keep in mind, this is my first TDI build, and first time I am opening up the engine.
Thanks =D
Piston UPDATE:
So here is the update on the Pistons
ALH, ASV & ARL +0.5 Pistons
ALH 79.44mm Stock Piston
Weight w/ Pin w/o Rings = 759g
Pin weight = 207g
Skirt = 79.40mm (used piston)
Crown = 78.87mm
Crown thickness = 6.06mm
Valve relief depth 1.03mm
Piston height (bottom of skirt to top of crown) = 71.83mm
Pin hole to crown = 32.9mm
Bowl depth = 16.6mm
Bowl width = 38.16mm
Weight with Bowl full of water = 780g
The bowl holds 21g of water.
ASV Standard 79.5mm (79.46mm) Piston
Weight w/ Pin w/ Rings = 771g
Pin weight = 207g
Skirt = 79.46mm
Crown = 78.99mm
Crown thickness = 8.91mm
Valve relief depth 1.03mm
Piston height (bottom of skirt to top of crown) = 68.69mm
Pin hole to crown = 32.9mm
ASV 0.5mm over may be shorter from Pin to Crown.
Bowl depth = 17.39mm
Bowl width = was not measured sorry.
Weight with Bowl full of water = 795g
The bowl holds 24g of water.
ARL 79.5mm +0.5 (79.96mm) Pistons
Weight w/ Pin w/ Rings = 797g
Pin weight = 203g
Skirt = 80.00mm
Crown = 79.33mm
Crown thickness = 11.65mm
Valve relief depth 1.10mm
Piston height (bottom of skirt to top of crown) = 68.50mm
Pin hole to crown = 31.46mm
BUT the valve relief does not have an edge so add 1.10mm = 32.56mm
Bowl depth = 17.64mm
Bowl width = 38.01mm
Weight with Bowl full of water = 819g
The bowl holds 22g of water.
This is as accurate as I could get with my Digital Caliper
Oil Gallery Update: FIND IMAGES ON PG.5 post #75 http://forums.tdiclub.com/showpost.php?p=5230411&postcount=75
The ASV & ARL oil gallery seem to be positioned a little differently.
The ASV pistons have 3 holes all together, I would think this would allow it to cool better and catch oil better.
The ARL pistons have 2 holes, and the hole that would receive the oil from the oil jet/squirter is closer to the pin and wall of the piston. I will be customizing this on the ARL pistons by funneling the gallery hole to help catch the oil better.
I have done some engine mods to my car. The last Dyno I was pushing 181hp & 325 ft lbs.
I have got a head made with larger valves, Ported, dual valve springs, stage 2 colt cam, new lifters and some ARP headstuds that I am going to be installing really soon. But while I have the engine open I was thinking I should put new pistons, rods and rings in being that I want to push over 200+hp.
Here is my questions:
What pistons would work best for the ALH that are
A. Standard ALH size (I don't want to bore the block)
B. Same hight so I don't have to shave the block
C. Can handle the power I want to push
D. Let's just say a drop in piston.
E. OR stick with stock ALH pistons.
Should I make the piston valve reliefs larger?
My intake valves are 36.9mm I believe, and my exhaust valves are 33.5mm
I have a stock core piston someone gave to me, and it seems that the intake relief grooves are 38.2mm and the exhaust reliefs are around 33.88mm
What rods would be best for the ALH that
A. Can connect to the ALH crank
B. Can handle the power
C. Can handle any upgrade I throw at them in the future.
D. Will work with the piston upgrade
What kind of power are the stock pistons & rods good for?
Should I upgrade to a set of gapless rings or standard?
Example of gapless is something like total deal or sealed power oil control.
If you have a List of parts I should get while doing this job, that would be great.
I came accross alot of Ppl suggesting to put ASV pistons in, and that they work. But I came accross this forum:
http://forums.tdiclub.com/showthread.php?t=443136&highlight=Alh+piston+upgrade
Let's stay on topic as alot of these forums I read seem to get lost.
Please keep in mind, this is my first TDI build, and first time I am opening up the engine.
Thanks =D
Piston UPDATE:
So here is the update on the Pistons
ALH, ASV & ARL +0.5 Pistons
ALH 79.44mm Stock Piston
Weight w/ Pin w/o Rings = 759g
Pin weight = 207g
Skirt = 79.40mm (used piston)
Crown = 78.87mm
Crown thickness = 6.06mm
Valve relief depth 1.03mm
Piston height (bottom of skirt to top of crown) = 71.83mm
Pin hole to crown = 32.9mm
Bowl depth = 16.6mm
Bowl width = 38.16mm
Weight with Bowl full of water = 780g
The bowl holds 21g of water.
ASV Standard 79.5mm (79.46mm) Piston
Weight w/ Pin w/ Rings = 771g
Pin weight = 207g
Skirt = 79.46mm
Crown = 78.99mm
Crown thickness = 8.91mm
Valve relief depth 1.03mm
Piston height (bottom of skirt to top of crown) = 68.69mm
Pin hole to crown = 32.9mm
ASV 0.5mm over may be shorter from Pin to Crown.
Bowl depth = 17.39mm
Bowl width = was not measured sorry.
Weight with Bowl full of water = 795g
The bowl holds 24g of water.
ARL 79.5mm +0.5 (79.96mm) Pistons
Weight w/ Pin w/ Rings = 797g
Pin weight = 203g
Skirt = 80.00mm
Crown = 79.33mm
Crown thickness = 11.65mm
Valve relief depth 1.10mm
Piston height (bottom of skirt to top of crown) = 68.50mm
Pin hole to crown = 31.46mm
BUT the valve relief does not have an edge so add 1.10mm = 32.56mm
Bowl depth = 17.64mm
Bowl width = 38.01mm
Weight with Bowl full of water = 819g
The bowl holds 22g of water.
This is as accurate as I could get with my Digital Caliper
Oil Gallery Update: FIND IMAGES ON PG.5 post #75 http://forums.tdiclub.com/showpost.php?p=5230411&postcount=75
The ASV & ARL oil gallery seem to be positioned a little differently.
The ASV pistons have 3 holes all together, I would think this would allow it to cool better and catch oil better.
The ARL pistons have 2 holes, and the hole that would receive the oil from the oil jet/squirter is closer to the pin and wall of the piston. I will be customizing this on the ARL pistons by funneling the gallery hole to help catch the oil better.
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