Troopzilla (1 Viewer)

[dadinabarrel]

I started with a motor that had done 50,000km since complete rebuild, pulled it to pieces to port and polish the head and found this:

Fxxx, you wouldn't believe it, cracked to #5, all 6 pre cups cracked. I've got the reciept for the motor, but something does not add up. Maybe he lied about the K's since the work was done. There is no km on the invoice.

Pistons and cylinder bores look A1. Uses no oil. Blows no smoke.

Standard 10mm VE running on one of the medium sides of the pin, 10" barrel WTA, Denco Turbo, was only averaging 300C post EGT, tappets were all within spec, I haven't checked the timing yet, but I'll set it to 1.09 when I do.

Observations:

The EGT probe was 200mm past the turbine exit so I'm thinking that it was reading low.

New EGT probe position with probe tip 50% into pipe:

I don't know what the AFR was running at previously but I have installed digital on board AFR for restart/tuning.

It's running LPG over the top. I have seen arguments for and against, I can't make my mind up about this one, but I love the clean burn and the extra boost I get when it comes on so I'm hesitant to take it off.

I took the head to Davilak's in Hamilton Hill (I've used them for 25 years) for a quote on cracktest and weld.

They said don't bother no one repairs these things. That's when I started stressing out...

But there is a happy ending - they sold me a complete brand new 1HZ head for $1200, the cheapest I can find on eBay is $1650. All I have to do is fit the cam gear and bolt it on. So a good result in the end.

I'm still going to match port and polish

What is the concensus on the LPG?

 

[roscoFJ73]

1HZ 200hp/5000rpm, you know you want to....

Says it all. These are slow plodding engines,if Toyota wanted them to go fast they would have made a direct injection with factory turbo and 24 valves version,ohh they did.

 

[dadinabarrel]

Hahahaha you just opened up the biggest bag of worms



This guy knows how to make a 1HZ fly (not me) yet...

 

[yotahed]

What volume of LPG are you pumping in there? I would be hesitant to use propane on a non DI engine since the compression is so high on the 1hz + turbo + more fuel= very high combustion pressures. If you're planning on retaining the propane, I would suggest lowering the compression a half a point at least. Alternately you could switch to Meth/alcohol injection. Much safer when used correctly and gives slightly lower performance results. I would leave the propane for something other than a daily driver. Just my opinion tho.

I would say that head has higher milage than was indicated.

 

[dadinabarrel]

Not sure about the volume, but the gas solenoid opens at 2psi boost. On an 80L tank of diesel I usually empty the 34L LPG tank first or at around the same time.

It already had a 5 notch (thickest) gasket on it but there is no way of telling how many times the head had been machined. At least now I'm starting with a brand new head and a new 5 notch gasket. That's as low a compression as I can get it without major structural change. I think all the rods are the same length, cranks are the same stroke. You could machine the piston tops maybe, but I'm not that keen as I want it to last.

When it's back together I'm going to target 20psi at 20:1 AFR and see where the EGT's end up, then reduce/increase the AFR to meet a max of 600'c EGT pre turbo.

I think you're on the money with the mileage, I reckon I got misled when I bought it

 

[Wheelingnoob]

I would say the trifecta of poor EGT placement, LPG injection, turbo are the cause of the cracked head. I can not imagine why one would put LPG and a turbo on an engine that was never intended to make big power. There are much better starting points namely the same engine but DI.

Ill bet with the EGT probe that far way from the turbo you where losing 150ish c from pre turbo.


...via IH8MUD app

 

[dadinabarrel]

It does look that way doesn't it...

A 1 HDT would be a lot better but that's not on the menu at the moment

A 1HZ is more than capable of handling the power, that's getting proven again and again, but the key is EGT management.

I'm putting a massive WTA, 19mm lines, a 4L resevoir and a bosch cobra to my intercooler circuit

3.5" plenum inlet manifold with 3" centre inlet

All that will allow me to cool more efficiently, push more boost and breathe better, which will put me in a lower EGT range so I think I'll be ok. There are some very clever people on this forum and I'm learning from all of them

 

[yotahed]

You're using roughly just under half a litre for every litre of diesel of LPG.... Seems to me that is a lot. And for it to come on at 2 psi seems a little soon. Should be more like 3/4 of your max boost to be more useful. Not much heat is generated at 2psi. Even most water/meth systems aren't set to come on until 5-6psi at the lowest. I'm not saying don't run it, do whatever you want, just that the volume seems quite eccessive and is set to come on too soon. If you plan to run 20 psi, I'd set it to come on at a progressive rate starting at 10-12psi. You may lose a bit of bottom end power, but there again, too much too soon and its like flooding out a gas motor and your basically wasting it. Same thing happens with water/meth with excessive amounts injected too early.

 

[dadinabarrel]

That sounds like good advice Yota

I'm finding info on the LPG over diesel pretty thin on the ground

 

[ozwallaby]

Is there any way you could make your exhaust manifold more "flowing"... just looking at it, it seems like it would inhibit smooth exhaust transition from head to turbo.....

 

[dadinabarrel]

According to the manufacturer this is a far better flowwing manifold than the standard manifold. The shorter the run from the port to the collecter (equal length) gives you better turbine response.

 

[ozwallaby]

My understanding of "equal length" is the distance from port/valve to turbine is of equal length..... that's why the ricers have a tangle of pipes between head and turbo' getting those header pipes an equal length, so in theory the exhaust pulses get to the turbine at equal intervals giving the turbine (and therefore the compressor) a more even rate of spin, so more stable boost.... maybe there are other advantages (response as you mention) to having a pipe like yours.... that's my 2 bobs worth anyhow

 

[Spudman]

Hey Tim

How goes it mate, so many West Aussies on here

That video is awesome mate, live that turbo spinning, have you got the 3 inch straight thru on her, I've just done that to my 12HT.

Mate there is limited info on gas injection as it's relatively new and most of the work is being done on the later model cars like the 200 series.

Have you been www.lcool.org gotta be a member, I used to be a member and there is s*** loads on the 1HZ with a turbo, unfortunately they call them smoke grenades

I'd luv to hear more about this gas injection, might be project for me down the road.

Also with your probe for the pyro I have mine post turbo with intercooler and it's reading 300 degrees at 110km/h but that's another

Spudman

 

[dadinabarrel]

My understanding of "equal length" is the distance from port/valve to turbine is of equal length..... that's why the ricers have a tangle of pipes between head and turbo' getting those header pipes an equal length, so in theory the exhaust pulses get to the turbine at equal intervals giving the turbine (and therefore the compressor) a more even rate of spin, so more stable boost.... maybe there are other advantages (response as you mention) to having a pipe like yours.... that's my 2 bobs worth anyhow

What you're saying is true mate, but of the two manifold configurations (log and tubular)(cast or welded)

https://forum.ih8mud.com/threads/turbo-faq-and-info.132674/

As quoted from the FAQ:

" For better boost response, minimize the exhaust volume between the exhaust ports and the turbine inlet "

A welded log style manifold with the shortest equal runners has got to be better than the standard cast manifold. The only other option on our market which is a cast split pulse manifold half (use your original back half) would meet the technical criteria better but I couldn't justify the extra $$$ for the level of performance I'm at. There are no ceramic coated I/O, fully welded, gusseted, tubular welded manifolds available - that would be my first choice every time.

It does look very tidy as well

 

[dadinabarrel]

Hey Tim

How goes it mate, so many West Aussies on here

That video is awesome mate, live that turbo spinning, have you got the 3 inch straight thru on her, I've just done that to my 12HT.

Mate there is limited info on gas injection as it's relatively new and most of the work is being done on the later model cars like the 200 series.

Have you been www.lcool.org gotta be a member, I used to be a member and there is s*** loads on the 1HZ with a turbo, unfortunately they call them smoke grenades

I'd luv to hear more about this gas injection, might be project for me down the road.

Also with your probe for the pyro I have mine post turbo with intercooler and it's reading 300 degrees at 110km/h but that's another

Spudman

G'day Spud
I am the victim of my own enthusiasm...
I started off with a reall good Troopy that just had notchy syncros on 2nd and 3rd, so I thought I'd change it into an auto while I had the chance (hadn't been done in a HZJ75 before apparently) https://forum.ih8mud.com/threads/hzj75-troopy-automatic-conversion.794160/

Then I decided that while it was out I would explore all the possibilities for bolt on/tweak modifications that were possible to allow me to get the most out of what I had due to the power loss that comes with the auto. Amazing what you can to do to a 1HZ and the potential they have. That's the video above, I've edited the post as I didn't say it wasn't mine but belongs to a guy called Z()ltan. That was at 10psi, I think he's been running it at 33psi for a couple of years now and it's still going strong. You just have to do it right.

I should have done a build thread because the motor is now stripped down to the block (auto is in) and I was just about to put a new head on it over the next few days but I'm now probably going to go all the way and put the turbo pistons/rings/rods into it as this is the last time this head is ever coming off

I'm still of two minds with the gas. There is some conflicting data. I think the guy who set mine up was using the gas as a power source, which is great, it pushes you back in your seat when it kicks in and burns clean. I just hope that the cracked head I found was due to the way the whole package was set up. The EGT was 200mm down the pipe past the turbo exit, which would read cool. He may have regularly given it stick thinking that was fine and it wasn't due to a low reading. It is indisputable that a pre turbo EGT probe in 50% mid stream is the best setup for accuracy and response, so that's what I'm going with.

I'm a member of LCOOL and there is a lot of info there, but I think I can confidently say the IH8MUD has better, more accurate information from a wider cross section of experienced/technically expert people.

It is good to have a number of forums to cross reference against each other but IH8MUD is the best

 

[Dougal]

Just like Jeremy (wheelingnoob) I can see the same problems.
1. Post turbo EGT measurement is useless.
2. LPG makes for massive increases in cylinder pressure for the power generated.
3. 10psi ain't enough for the power you claim.

For the rebuild looks like you've got the EGT position sorted, but you need to ditch the LPG or this will likely happen again. You also need to run more boost.

 

[dadinabarrel]

Mmm maybe I should change my signature. Is that what you think I'm claiming? That's a you know you want to that's all...

Soooo undecided about the LPG

I'm targeting 20 psi at 20 AFR if I can get xxxx rwhp? out of it with good drivability I'll drop the gas

Or I'll cut the volume back and change the solenoid setting to make it come in at higher boost just for the clean burn as opposed to the high volume low boost performance setup as it stands now.

I'd love 200rwhp it's a nice round number, though I most likely won't get that out of a 10mm VE no matter how much boost I run

I'm pretty confident I've done as much as I can in terms of intercooling and flow, at my budget. EGT will be the limiting factor.

Do you think that with no gas, brand new match ported and polished head, turbo pistons, rings and rods, 3.5" plenum inlet manifold (3" centre fed) 3.5mm wall steam pipe log exhaust manifold, gt2871, pie warmer with Bosch cobra, 19 mm lines and 4L reservoir, 3" short system, maxed 10mm VE and max sustained EGT of 650'c I'll be ok?

I have looked at ceramic coating everything but I now can't afford it.

What have I missed in my build?

 

[Dougal]

If your tune is good, then it will burn clean with no lpg.

 

[dadinabarrel]

Aaaarg, so hard to walk away from something that costs quite a bit of money and is working fine.

 

[Spudman]

Unless they can ultimately prove that the gas is causing the problem, I'd leave it, I've heard so many good reports, my mate just put gas injection on his Brunswick Diesel and he swears by it