Hybrid Alh

[n0.j0y]

For a while now ive wanted to build a hybrid alh, i thought i’ve settled on a bhw block with an alh head but seeing how hard it is to find a block around my parts, i was wonder what other 2.0 blocks i could use.
I’ve read into multiple threads and i’m seeing that the bew and bhw where the ones mostly used but would it possible to use the newer tdi 2.0 like the cjaa or cbea i haven’t looked into these blocks yet and there similarities or differences so any information is useful.

 

[jimbote]

For a while now ive wanted to build a hybrid alh, i thought i’ve settled on a bhw block with an alh head but seeing how hard it is to find a block around my parts, i was wonder what other 2.0 blocks i could use.
I’ve read into multiple threads and i’m seeing that the bew and bhw where the ones mostly used but would it possible to use the newer tdi 2.0 like the cjaa or cbea i haven’t looked into these blocks yet and there similarities or differences so any information is useful.

Common rail will not work unless you go full mechanical and you swap to BHW pistons..there is no provision for the crank sensor in the block nor will the crank accept a tone ring.

 

[n0.j0y]

can you explain that more for me? sorry just tryna understand exactly what ur saying.

 

[jimbote]

can you explain that more for me? sorry just tryna understand exactly what ur saying.

Ugh, exactly what I said? It won't work. Period.

 

[T1MMBOJONES]

Ugh, exactly what I said? It won't work. Period.

sounds like he should be building an engine

 

[n0.j0y]

i mean i’m pretty new at engine building but other than the fundamentals i’m not by any means an engine builder, with that being said the best way of figuring it out is to jump right in we’ll in my opinion.
anyways long story short only bhw block would work so what i’m hearing is i have to take my chances getting a block shipped sight unseen

 

[03Golfer]

Can machine ALH block to 2.0

 

[n0.j0y]

i’m considering just rebuilding my alh.
i’d like to have a reliable alh tht can push close to 300whp, i’m wonder if boring it out would make tht way easier if not i’d think i’ll stick with asv pistons maxspeeding rods arp bolts all around.
the alh rn should be my go to so all the information anyone can give me on beefing it up would be highly appreciated all the lil stuff and hassles tht come with it.

 

[GlowBugTDI]

i’m considering just rebuilding my alh.
i’d like to have a reliable alh tht can push close to 300whp, i’m wonder if boring it out would make tht way easier if not i’d think i’ll stick with asv pistons maxspeeding rods arp bolts all around.
the alh rn should be my go to so all the information anyone can give me on beefing it up would be highly appreciated all the lil stuff and hassles tht come with it.

Goodluck hitting those numbers. If you truly want 300whp your going to need very deep pockets and you may as well do a bhw hybrid. I think your going to want to do a lot more reading before diving into this. 300hp out of an alh (even built) isn't going to last very long. You have a ton of structural issues to consider... actually trying to make that hp is just the tip of the iceberg.
I'm not saying 300whp isn't achievable as it totally is. Im just saying might as well have an engine built for at least close to that (ideally more) that can handle all the money you'll throw at it trying to hit 300whp.

 

[03Golfer]

What is your application/ vehicle type, and usage goals? How is the ALH currently set up? My suggestion to bore the ALH is based on your suggestion that sourcing a BHW block is difficult. The real strength upgrade comes from the crank, rods, and pistons from the BHW. Buying the complete BHW is the most affordable way to go. I would agree with above suggesting 300hp may be a bit of a lofty goal, but 300 ft/lbs and 200hp may be attainable on something resembling a budget.

For some interesting reading and a true VE 300+ hp build check out https://forums.tdiclub.com/index.php?threads/replacment-for-displacment.315943/

 

[n0.j0y]

ok wow i see what you guys mean now tht twin turbo alh on tht thread is seriously built, he is looking for over 300whp tho, i just want a little over 250 whp reliably, i’m seeing that he reinforced the internals would that be necessary with a bhw hybrid? and if i stick with the alh block how would i go about reinforcing it?

my current build is a 2002 mk4 jetta gls currently about 245,000 miles on motor and body the motor seems heathy but has a bit of blow by and i have found oil in places they shouldn’t be (intercooler, intake, turbo inlet) slight bit of a leak on the rear main seal, also has a tiny bit of air in the fuel lines,
i want a daily that i can have fun in but also win some races, (it’s currently bone stock) i haven’t opened it up but i am planning on opening the head and seeing if it’s worth re building.

i’m curious about all the weakness and flow on the alh i know the bottom end components are usually first to go but thts about it,

 

[J_dude]

has a bit of blow by and i have found oil in places they shouldn’t be (intercooler, intake, turbo inlet)

If you do a little reading around this site you will find that is completely normal.

 

[T1MMBOJONES]

as awesome/reliable as the alh is and as much as i loved mine, especially the looks of a mk4 wagon, i do not miss it one bit! for what youre trying to achieve i think you should strongly consider a common rail...even bone stock they are night and day different and much more responsive/comfortable. they can be found pretty cheap these days, especially if high mileage is not a concern. if you are willing to turn a wrench a timing belt job is fairly easy and so is swapping in a cp3 pump while you are at it. a basic tune and they liven up. you may not hit your goal of 250hp with just that but i still reckon you will enjoy it and "win some races" numbers on paper dont mean much....

 

[CanadianALH]

as awesome/reliable as the alh is and as much as i loved mine, especially the looks of a mk4 wagon, i do not miss it one bit! for what youre trying to achieve i think you should strongly consider a common rail...even bone stock they are night and day different and much more responsive/comfortable. they can be found pretty cheap these days, especially if high mileage is not a concern. if you are willing to turn a wrench a timing belt job is fairly easy and so is swapping in a cp3 pump while you are at it. a basic tune and they liven up. you may not hit your goal of 250hp with just that but i still reckon you will enjoy it and "win some races" numbers on paper dont mean much....

Guy with a new tdi told me he did a turbo and a tune beat a 5.7 challenger lol. I’m pretty sure with a bigger turbo on my ALH I’d be able to give one of those a run for its money. As Carol Shelby once said “ Horse power sells cars torque wins races”. At the end of the day no matter how much faster something is you can rest assured (minus a EV) they sure aren’t doing 45 mpg.

 

[n0.j0y]

If you do a little reading around this site you will find that is completely normal.

could you guys give me the links to said threads ive looked around and still no luck finding something that will benefit me

 

[CanadianALH]

could you guys give me the links to said threads ive looked around and still no luck finding something that will benefit me

best thing you can do is search google with tdi club in along with the question.

 

[J_dude]

could you guys give me the links to said threads ive looked around and still no luck finding something that will benefit me

Google works much better than the search function here.

alh oil in intercooler blow by site:forums.tdiclub.com - Google Search

 

[Alberta 7.3]

Common rail will not work unless you go full mechanical and you swap to BHW pistons..there is no provision for the crank sensor in the block nor will the crank accept a tone ring.

Common rail has a crank sensor, well, at least my CBEA has one on the back. Probably a different tone ring tooth count though.

 

[burpod]

my personal opinion is to not lower compression. instead, upsize injectors, retard timing

 

[jimbote]

Common rail has a crank sensor, well, at least my CBEA has one on the back. Probably a different tone ring tooth count though.

Yeah, but it's built into the rear main seal. The CR block has NO provision for the ALH style sensor nor does the crank have the holes or even bosses to mount to ALH reluctor wheel.

 

[dieseldonato]

my personal opinion is to not lower compression. instead, upsize injectors, retard timing

A lot of lowering compression was for emission reasons, you need substantially higher boost before needing to worry about reducing compression ratios.

 

[n0.j0y]

let’s talk turbos, GTD GTB GT what’s the difference? will a GTD1756 make more boost than a GT1749? will a billet GT1749 make more boost than a cast GT1746? can they push more boost than advertised? or will it kapoot itself? how would one know the best turbo for them? how can you safely push turbos past there limits???. all answers and excepted and appreciated.

 

[dieseldonato]

Gt, gtb, and gtd refur to the generation of vnt. Gt being first generation gtd being the latest (as far as I know) generation. Given everything else is close to the same, you should expect better spool characteristics from a gtd vs a gtb or gt turbo.
Making more boost isn't really how a turbo is or should be rated, it's the maximum pressure thats safe for the compressor. In vw land garret turbos the first two numbers signify the chassis or turbo size. 15,17,18, 20 etc. The last two are compressor size (ish) given wheel design is consistent a 1749 will flow less air then a 1752,4, or 6 at a given pressure rating. All 3 can have the same upper boost/pressure rating. Different wheel construction adds variables for pressure/ flow. You'd really need to talk with whomever made the turbo, or at least compare Compressor maps. Usually billet wheels will flow more/make more boost, but it's not always the case. There is also hydro bearing vs ball bearing to consider. Ball bearing turbos have been proven to be pretty dependable over the last 10-15 years in my experience, however they won't take over speeding in stride and don't like being abused in general. They typically have water cooling as well, since they don't get anywhere near the oil flow a hydro bearing turbo does. They do spool faster then a hydro bearing turbo. Which leads to better all around driving characteristics and transient response being much better then a hydro bearing turbo.
Some of that can be negated with a good tune on a hydro bearing turbo.
Hydro bearing turbos are very rugged, they take quite a bit if crap and keep on chugging. You're basically limited to compressor tip speed as far as upper rpm limits go. They take heat a bit better then ball bearing turbos, being flooded with oil at all times. Lastly they are cheaper. Bit slower to boost, and transient response isn't as good. Generally speaking were talking response time in hundreds of rpm, 200-300 ish difference.
Personally, whenever I get around to getting a larger turbo it will be a gtd vs the gt I have and a 20 series vs the 18 series I have. Still on the fence with ball bearing vs hydro bearing.

 

[Bradm]

Gt, gtb, and gtd refur to the generation of vnt. Gt being first generation gtd being the latest (as far as I know) generation. Given everything else is close to the same, you should expect better spool characteristics from a gtd vs a gtb or gt turbo.
Making more boost isn't really how a turbo is or should be rated, it's the maximum pressure thats safe for the compressor. In vw land garret turbos the first two numbers signify the chassis or turbo size. 15,17,18, 20 etc. The last two are compressor size (ish) given wheel design is consistent a 1749 will flow less air then a 1752,4, or 6 at a given pressure rating. All 3 can have the same upper boost/pressure rating. Different wheel construction adds variables for pressure/ flow. You'd really need to talk with whomever made the turbo, or at least compare Compressor maps. Usually billet wheels will flow more/make more boost, but it's not always the case. There is also hydro bearing vs ball bearing to consider. Ball bearing turbos have been proven to be pretty dependable over the last 10-15 years in my experience, however they won't take over speeding in stride and don't like being abused in general. They typically have water cooling as well, since they don't get anywhere near the oil flow a hydro bearing turbo does. They do spool faster then a hydro bearing turbo. Which leads to better all around driving characteristics and transient response being much better then a hydro bearing turbo.
Some of that can be negated with a good tune on a hydro bearing turbo.
Hydro bearing turbos are very rugged, they take quite a bit if crap and keep on chugging. You're basically limited to compressor tip speed as far as upper rpm limits go. They take heat a bit better then ball bearing turbos, being flooded with oil at all times. Lastly they are cheaper. Bit slower to boost, and transient response isn't as good. Generally speaking were talking response time in hundreds of rpm, 200-300 ish difference.
Personally, whenever I get around to getting a larger turbo it will be a gtd vs the gt I have and a 20 series vs the 18 series I have. Still on the fence with ball bearing vs hydro bearing.

Very informative