300 hp Alh

[alhbeliever]

Hi guys,
I am currently building a 300 hp alh. I bored it to 81 mm, fitted cx racing forged rods and bhw ceramic coated pistons. I also installed a 3 hole head gasket to reduce compression. As for the head, i ordered a 272 degree/10.4 mm lift dbilas cam along with stiffer valve springs. For the fuel, i have an in tank pump paired with an 11 mm pump and .360 gibonata race nozzles. I ported the head and installed a brm intake manifold (allegedly the best flowing tdi manifold sold in America). For reliability purposes, i would like to limit the torque to 270 wlbsft to the wheel. That way i can hit that magical 300 whp number (@6k) and keep my 02j transmission safe. The only mods done to the trans are a second hand lsd from ebay and a .592 5th gear. As for the turbo, i was thinking hx30 because its the smallest turbo that can flow how much i would need and can be found at around 500$ shipped, but i haven't bought one yet. Suggestions would be great. My turbo manifold is equal length 4-2-1 style t3 made by myself. The torque curve that i would like would put me in vacuum from idle to around 3k for economy (this is still my daily driver) and 270 wlbsft of torque from 3k to 6k. I planned to put a low boost spring in the wastegate and control the boost with a solenoid. For example, I could put a 10 psi spring in the wastegate and letting it open until 3k. After 3k, the boost controller would module the boost all the way up to 6k rpm (boost increasing with rpm while staying at around 270 wlbsft until redline). The max boost i plan running is around 40 to 45 psi. The problem is, a friend of mine told me that boost wont be able to reach 40 psi with a low boost spring in the wastegate since exhaust gasses would open the 10 psi spring from the inside while trying to increase boost regardless of what the boost solenoid is signaling. Is that possible? If it is what would you guys suggest as a solution? What does my set up lack? Any input is greatly appreciated.
Thanks

 

[Jard]

I am no expert, but your numbers sound off.
300whp, takes a lot of work. And with that power comes great torque, you are well north of 450tq I am guessing.
If you are only wanting 270tq, a vnt17 can get you there fairly easy. But you are only going to have around 150whp or so.

Either way, sounds like fun.

 

[lemoncurd]

I am no expert, but your numbers sound off.
300whp, takes a lot of work. And with that power comes great torque, you are well north of 450tq I am guessing.
If you are only wanting 270tq, a vnt17 can get you there fairly easy. But you are only going to have around 150whp or so.

Either way, sounds like fun.

That torque figure can be hit with a properly sized turbo + lowered compression + rev the damn thing out. Past 5252ish rpm torque and HP flip.

I'm going to watch this thread, ALH generally isnt something people make power on (to my knowledge) as PD and CR are much easier/cheaper/capable in comparison.. atleast as far as I know, I could be wrong

OP, HX30 should totally work providing you can feed it enough air. Lower the compression, put bigger nozzles in, put as big of a cam you can in, port the head + increase valve size, then rev it out to maybe 7k?

You obviously need to build the bottom end to support it. AFAIK the ALH bottom end holds strong until like 200whp/350-400tq stock

I've seen some PD/CR's go to about 7k, though my memory may be faulting me.

There is a guy (in i think brazil) who "machined" his engine with nothing but power/hand tools and it makes considerable power. I'll try to find him

With enough time + money anything is possible good luck!

 

[alhbeliever]

That torque figure can be hit with a properly sized turbo + lowered compression + rev the damn thing out. Past 5252ish rpm torque and HP flip.

I'm going to watch this thread, ALH generally isnt something people make power on (to my knowledge) as PD and CR are much easier/cheaper/capable in comparison.. atleast as far as I know, I could be wrong

OP, HX30 should totally work providing you can feed it enough air. Lower the compression, put bigger nozzles in, put as big of a cam you can in, port the head + increase valve size, then rev it out to maybe 7k?

You obviously need to build the bottom end to support it. AFAIK the ALH bottom end holds strong until like 200whp/350-400tq stock

I've seen some PD/CR's go to about 7k, though my memory may be faulting me.

There is a guy (in i think brazil) who "machined" his engine with nothing but power/hand tools and it makes considerable power. I'll try to find him

With enough time + money anything is possible good luck!

Yeah exactly, i planned reving it to 6k and the bottom end is already built, the true problem is boost control

 

[Jard]

Interesting, you learn something new every day.

6k, I would love to hear that when it is all built and running.

 

[J_dude]

What exactly is the reason for wanting less torque..? I thought that was the fun stuff! Lol

 

[GlowBugTDI]

What exactly is the reason for wanting less torque..? I thought that was the fun stuff! Lol

Blow the 02J trans. Their limit is about 300tq...at least from what i have been told and read.

 

[alhbeliever]

What exactly is the reason for wanting less torque..? I thought that was the fun stuff! Lol

I want to keep the 02j trans and keeping it reliable. I could swap to a 02m but it would be expensive.

 

[IndigoBlueWagon]

This was my Wagon back in '08. Stock internals. You can see the lines cross at 5250. It would rev to 6000, but much past 5500 I felt like it mostly made heat.

As an aside, I did countless track days in that car, original transmission lasted to 385K when I replaced it because the synchro for the 5-4 downshift was getting difficult. Otherwise it was still fine.

 

[alhbeliever]

To make power past 5k you would need a lot of boost since the engine becomes inneficient at those revs. You would also need a very flowy head and an agressive cam. Otherwise, like you said its just making a bunch of heat.

 

[turbocharged798]

The ALH is really best at being a torque monster with its small head ports. That's why you can make 400 ft/lbs at 2500 RPM.

 

[alhbeliever]

Some guy on another forum told me that the best way to limit te torque would be by limiting fuel. According to him, i could lean out the engine tu manipulate the torque curve. While this seems promising, i am worried about egts. I know that performance diesel run rich to cool down egt levels. If i lean out the engine from 4k to 5k would the egt get to dangerous levels?

 

[lemoncurd]

Some guy on another forum told me that the best way to limit te torque would be by limiting fuel. According to him, i could lean out the engine tu manipulate the torque curve. While this seems promising, i am worried about egts. I know that performance diesel run rich to cool down egt levels. If i lean out the engine from 4k to 5k would the egt get to dangerous levels?

EGT would depend on multiple factors

Nozzle size and amount of fuel you can push through said size will greatly effect EGT's because the injection duration will be shorter.

Shorter injection duration = cleaner burn = lower EGT

Head flow is also a major contribution to lowering EGT's, port + cam + valve the head and it will flow better there for less pressures/EGT's

Ultimately, you have to start somewhere, build it and watch EGT's. If they are too high with everything put into place like above, then spray water meth into the intake to drop the temps

What exactly is the reason for wanting less torque..? I thought that was the fun stuff! Lol

Low end power/torque on our small transmissions/engine is really really violent above like 300 pounds (old stuff) or 400 pounds (new stuff like CR and DSG)

It's better to look at what the honda guys have done to get around this, rev the thing out and let it sing

 

[lemoncurd]

Yeah exactly, i planned reving it to 6k and the bottom end is already built, the true problem is boost control

Boost control can be done with a wastegate, turbo smart has some electronic ones. Worst case just wastegate it off boost

I am unfamiliar with the older stuff like ALH/PD's but if you have a N75 valve you could feasibly make a custom doodad to read that signal, then translate to something the turbo smart electronic actuator can respond to

If you dont have an n75 or want to do something simpler I think the electronic ones can just read boost data off the canbus, you then just program the actuator module to open/close/partial open at XYZ

 

[BRMman]

The problem is, a friend of mine told me that boost wont be able to reach 40 psi with a low boost spring in the wastegate since exhaust gasses would open the 10 psi spring from the inside while trying to increase boost regardless of what the boost solenoid is signaling. Is that possible? If it is what would you guys suggest as a solution? What does my set up lack? Any input is greatly appreciated.
Thanks

If you have a waste gate opening at 10 psi it will certainly not make boost beyond that. I can think of one easy way around that. If you have an external hose going from boost side to the waste gate, interrupt this hose with a 12 volt solenoid. It would need to wired to a switch, unless your boost controller has an out put that would switch this solenoid. And then, would you want a normally open or normally closed? Each would have advantages and disadvantages.

 

[alhbeliever]

EGT would depend on multiple factors

Nozzle size and amount of fuel you can push through said size will greatly effect EGT's because the injection duration will be shorter.

Shorter injection duration = cleaner burn = lower EGT

Head flow is also a major contribution to lowering EGT's, port + cam + valve the head and it will flow better there for less pressures/EGT's

Ultimately, you have to start somewhere, build it and watch EGT's. If they are too high with everything put into place like above, then spray water meth into the intake to drop the temps



Low end power/torque on our small transmissions/engine is really really violent above like 300 pounds (old stuff) or 400 pounds (new stuff like CR and DSG)

It's better to look at what the honda guys have done to get around this, rev the thing out and let it sing

I might reduce the compression ratio to like 17.5 to 1. If i do that, i think my egt will be fine. It might reduce efficiency, but im at 1700 rpm cruising on the highway and the big turbo would put me in vacuum under 3k rpm. I think the car will still maintain good economy.

 

[alhbeliever]

Thanks for the input guys, i made my decision. I will lower the compression ratio and i will ask the tuner to deliver 270 wlbsft of torque worth of fuel from 3k to 6k rpm. The wastegate will have a big spring in it and i will add a manual boost controller so it doesnt open till 45 psi or whatever my max boost is. With the lower cr, i am not to worried about egts. What do you guys think?

 

[IndigoBlueWagon]

I've never seen the logic of lowering compression and then replacing it with boost. What's the point?

 

[GlowBugTDI]

I've never seen the logic of lowering compression and then replacing it with boost. What's the point?

Wouldn't it be to pump more air? I could easily be wrong, but i thought that was why. Lower comp, push more air in, get more power. So your moving more air without getting super high compression numbers. right? Or at minimum moving more air while hitting those numbers...

Couldn't you also add more fuel then potentially because you'd have lower egts?

 

[IndigoBlueWagon]

If you're pushing 40 PSI into a combustion chamber with a lower CR, wouldn't you be getting the same amount of air and overall compression as pushing lower boost into a chamber with higher compression?

Also, I understand the big issue with getting high revs with these engines is getting injection timing advanced enough. ALHs combustion event is a pretty slow fire, and you have to walk a fine line between getting fuel in early enough and not starting combustion while the piston is still on the compression stroke. I used to set the timing at 115 in when I had the 6000 RPM tune to make sure the pump would get full advance when the electronic timing takes over.

 

[DannyS]

There were a few guys on here making 350+HP at 5500 rpm or so with 1Z and ALH engines.

Perhaps contact them? Their nicks are P0wer and Hatemi.

 

[BustedBolts]

You are way over thinking it, especially the boost control part. 02j's don't just instantly split over 300tq. If they did the majority of the mk4's I've tuned would have broken the transmissions. Use 0.300mm injectors for 300hp. And I would use a different turbo. A gtd2060vrk would even be enough. I run larger than Hx30 for turbos, and I spin my modified alh to 6500rpm. I did run it to 6800rpm for awhile but that was a little too much for an unmodified 11mm pump.

 

[lemoncurd]

I might reduce the compression ratio to like 17.5 to 1. If i do that, i think my egt will be fine. It might reduce efficiency, but im at 1700 rpm cruising on the highway and the big turbo would put me in vacuum under 3k rpm. I think the car will still maintain good economy.

It's a diesel, you wont pull vacuum even at idle.

I've never seen the logic of lowering compression and then replacing it with boost. What's the point?

To rev it out, sure keeping high compression + loads of boost would be great aside from possibility of valve float smacking pistons, and blowing the head off.

 

[alhbeliever]

I've never seen the logic of lowering compression and then replacing it with boost. What's the point?

You are way over thinking it, especially the boost control part. 02j's don't just instantly split over 300tq. If they did the majority of the mk4's I've tuned would have broken the transmissions. Use 0.300mm injectors for 300hp. And I would use a different turbo. A gtd2060vrk would even be enough. I run larger than Hx30 for turbos, and I spin my modified alh to 6500rpm. I did run it to 6800rpm for awhile but that was a little too much for an unmodified 11mm pump.

Well i want it to be reliable thats why i dont want to run obscene amounts of torque. Will .3 mm injectors be enough for 300 hp to the wheels? As for the turbo im looking for something that gives me room to run more boost if i upgrade to an 02m one day. Im also not interested in low range boost.

 

[alhbeliever]

It's a diesel, you wont pull vacuum even at idle.


To rev it out, sure keeping high compression + loads of boost would be great aside from possibility of valve float smacking pistons, and blowing the head off.

How is that? Could you explain the vacuum part?

 

[lemoncurd]

How is that? Could you explain the vacuum part?

Vacuum on a gasser is pulled from the intake manifold behind the throttle body (typically).

On diesels we do not have a throttle body, there for no vacuum. It is the reason our diesels, ALH all the way to CR's, have a vacuum pump. On my CJAA it is driven off the camshaft, not on the side with the timing belt

 

[lemoncurd]

See: https://www.ms-motorservice.com/en/technipedia/post/vacuum-pumps-basic-information/

 

[alhbeliever]

Interesting, i learned something today haha. I mean i put on 225/35/r18 on there so my cruising rpm is low in the city and highway it should be good enough to return me good mileage.

 

[Koehn]

Some guy on another forum told me that the best way to limit te torque would be by limiting fuel. According to him, i could lean out the engine tu manipulate the torque curve. While this seems promising, i am worried about egts. I know that performance diesel run rich to cool down egt levels. If i lean out the engine from 4k to 5k would the egt get to dangerous levels?

Diesels work exactly opposite of gas in terms of rich and lean temperature. A lean diesel is cold, while a rich one runs smokey and very hot. Lots of boost with very little fuel would have no negative effect on EGTs.

 

[KERMA]

so much wrong info in this thread.

just a couple of comments

1) lean does NOT increase EGT in a diesel. It's just the opposite. Lean => EGT is gasser think, if your tuner is telling you that you need to find someone who understands how a diesel works.

2) timing advance is required to overcome the ignition delay of approx. 1000 microseconds (according to bosch). That time delay remains more or less constant but the number of degrees per (micro)second increases as RPM increases, if that makes sense. The theoretical exact number for 1000 microseconds ignition delay is 6 degrees (crank, or 3 degrees cam) per 1000 rpm to maintain the same exact burn location relative to TDC. In practice that number can differ somewhat depending on a number of factors, but it's a good thumbrule.