Budget 4bd1t -> '94 FZJ80 Build (2 Viewers)

[lostih]

50mph in 3rd up 6% grades sounds like its running decently well. I cant wait to hear how it does once you get your boost and fuel worked out.

It seems unlikely that you would drop 10-20% of your boost in the short span of your big intake plumbing. It looked like you had plenty of crossectional area for you volumetric flow rate. Do you have too much volume making your intake a reservior? Is there a restriction in your intake that isnt visble in the photos?

Checking for leaks is a good place to start. Then, it's time to use your hotrod turbo!!!

I wondered about the reservoir issue too...maybe the intercooler and piping are large enough that at low boost/RPM it takes a bit to get it all to pressure? I found it held a little bit higher boost when cruising at 70...flopping between 5 and 6 psi.

 

[Wheelingnoob]

Think we just found your issue....

I alway pre load my actuator's a bit to get a good seal when closed. It also has an effect of raising the boost. Are there still threads showing on the rod that comes of the actuator? If its just bottomed out in the end pice just trim the actuator rod down a bit ( I had too).

I would try that first since its the easiest and quick. Then if that does not help move into putting a gauge pre cooler to see (just tee of the actuator line for a test). Also good time to start checking for boost leaks they can have a surprising effect.


...via IH8MUD app

 

[lostih]

Cool! So the rod end that goes on the wastegate pin is all the way threaded onto the actuator rod. Are you saying that the rod can be in threaded from the actuator diaphragm somehow? I imagine if I take it apart it will all make sense, but if there are any tricks to it let me know.

I bought the 18 and 21 psi springs as well...would you switch to one of those while I'm at it?

 

[Wheelingnoob]

Nope it sounds like yours has no more thread left on the rod its self. In that case you will need to use washers to space it. Like I said I started at 3/16" ish with mine. I would put the 21psi spring in at the same time. Save you doing it twice




...via IH8MUD app

 

[Wheelingnoob]

I would maybe thinking about it for a few min limit the changes to one thing at a time. Maybe try the washers first then the spring after. What you are trying to accomplish with the washers is enough preload to get you to advertised boost pressure of the spring. One thing preload usually does is speed up spool up because the actuators are linear in there opening for the most part. They start opening at about 1spi with no preload, that is wasted exhaust that should be pushing the turbine to make it spool faster.

A good trick if using washers is superglue them together first. Then you are just fiddling with one bolt one spacer and one actuator.


...via IH8MUD app

 

[Wheelingnoob]

Make any headway?

 

[lostih]

I didn't get to it yesterday. Spent most the day unpacking from the trip and cleaning the cruiser. I also put in a scion t1819 that I picked up as the wife wants a better radio for the next trip.

Your superglue trick is genius! I'm a little afraid I might have to extend the threads on the rod as I am already super close to the firewall. I was actually kind of surprised I got the actuator on at all.

 

[lostih]

Had some time this morning and tweaked a few things.

1. Found my exhaust leak. The band clamp between the turbine and cartridge was leaking a bit. I wasn't sure how tight to tighten that when I put it together. Now it's tightened until there was a noticeable increase in force required.

2. Changed the wastegate spring to 1.5 bar.

3. Gave the wastegate about 1/8" of preload.

This netted me about 2 psi at 2000 rpm full load. Still no boost at low rpm...so still need to hunt for a leak or another smoking gun.

I'm using the turbine from the larger exhaust housing in the smaller housing, but they visually looked the same. I'll try and rig up a pressure test soon, put the boost sensor pre intercooler, and possibly swap turbos. Maybe not in that order though.

I'm also still tinkering with the throttle cable. I got it to text book throw, but still didn't drive right. The best I've been able to do is shorter throw (1" instead of 1.3") with the cable being super loose to start with. When I had it se with the right amount of throw it seemed to think I always had the throttle mashed...it wouldn't shift unless my foot was off the throttle and if I stepped on the gas at all it down shifted. I'm wondering if I just need to live with leaving the cable loose and then letting of the fuel to shift.

 

[lostih]

I should say that's 2 psi additional. I now routinely see 10-11 psi where as before I almost never saw that...

 

[wrongway around]

ya the glue is the goods for sure especially when your doing three washers. just throughing some stuff out there but can you reverse your cable kickdown settup . can you route the turbo directly to the intake and try it , maybe something is in the intercooler. i know with my settup i can tell the difference between a stock air cleaner and a k&n. maybe your wastegate flapper is wasted.

 

[Dougal]

You need to do a pressure test on the wastegate actuator. Bike pump with a pressure gauge on a T and see what pressure it starts to move at. Normally in use it'll open a few psi below what you see on a bench test.

 

[lostih]

ya the glue is the goods for sure especially when your doing three washers. just throughing some stuff out there but can you reverse your cable kickdown settup . can you route the turbo directly to the intake and try it , maybe something is in the intercooler. i know with my settup i can tell the difference between a stock air cleaner and a k&n. maybe your wastegate flapper is wasted.

yeah I was wondering about the how the metal wastegate flapper really seals. Is the idea not that it seals, but that it just allows so little air through that most of it goes through the turbine until the flapper opens?

 

[lostih]

You need to do a pressure test on the wastegate actuator. Bike pump with a pressure gauge on a T and see what pressure it starts to move at. Normally in use it'll open a few psi below what you see on a bench test.

I'll try and stick a bike pump on it. When I swapped the spring out on it, it sure felt stiff....

 

[lostih]

Just did the old receipt roundup. Looks like I'm at around $3100 all in (but I bet I'm missing a few things...that figure has gone up $500 dollars in the time it took me to write this post as I remember other items). This could be done cheaper if one didn't have to buy two transmissions . And two turbos . Oh well. Live and learn. I spent about $175 dollars on nuts and bolts. I'm sure you could cut that in half by mail ordering some of the tricky stuff (like flywheel bolts...those where 35 bucks alone), but the local hardware store is convenient and well stocked...and if everyone bought everything online they wouldn't be there when I need them

Overall I'm pretty alright with where it turned out costwise. I got lots of help from lots of people that saved a bunch of money.

I'll do a full synopsis of the swap once I get everything sorted but the two things I know I'd do different right now are:

1) CNC or buy the adapter. It was a fun challenge to do it on manual machines and got me back in the machine shop...but it took way longer than it should.

2) Come up with a different oil filter relocation tube. I don't TIG so I had to make up a hose/flange combo. It ended up working out but was expensive and is one of the areas of the swap that I will always worry about.

 

[lostih]

I should also note that the $3100 figure includes engine purchase but also includes the sale of the old 1fze/trans/tcase and the NPR hulk...so this is the net expense of the swap so far...not that I'm done...but I hope I'm close...

 

[Wheelingnoob]

Can you post a pic of the actuator threaded area you are saying is bottomed out?

One thought on your boost issue. Maybe try for a test removing the actuator and and locking the W/G shut. See if you get any more boost that way.

I would try checking boost pre intercooler first though just to make sure you are not hitting a brick wall.


...via IH8MUD app

 

[ylexot]

Oh yeah, you have the intercooler too. It's easy to imagine a 10% pressure drop over a flow field like that. That's likely your "lose rag" in the plumbing. What pressure do you expect to see from your turbo? What pressure do you want at the intake?

$3600 all told ain't bad...

 

[Wheelingnoob]

Oh yeah, you have the intercooler too. It's easy to imagine a 10% pressure drop over a flow field like that. That's likely your "lose rag" in the plumbing. What pressure do you expect to see from your turbo? What pressure do you want at the intake?

$3600 all told ain't bad...

The 1.5bar spring in the actuator should be getting him 21psi, that's a lot more than 10%.

 

[Wheelingnoob]

One other thought that crossed my mind was intake restriction. How do you have the intake attached to yhe turbo? Got any pics? Maybe the suction from the tubo is pulling the couplers flat.

 

[lostih]

I had the same worry about intake. More that the filter my restrict flow. It's a goofy cone filter to 3" hard pipe followed by a 3" to 2.5" reducing silicon elbow into a rubber cobra head with a hard coupler.

Here's the rod. Kind of hard to see. I trimmed some of the thread off to get the 1/8" preload.

Here's general engine compartment. Only four joints in intercooler pipes. All silicon with band clamps.

Other than putting a bung in an intercooler pipe any other way to stick the boost sensor in pre-intercooler?