.....x2

 

Thanks Guys. 44mm wastegate is ordered.
Since I'm limited to 10 to 12lbs boost due to risk of ripping the stock block in two pieces, I need to keep boost low.
Now, I wait. lol.

 

Update:
The wastegate fixed the boost creep.
It was a busy summer so I pretty much worked on driveability thru the summer.
I started wot testing, and then was sinding I couldn't get past 4500rpm in 3rd. Rev's right to 6000rpm in 2nd and shifts beautifully.
Then, I ran in to more issues. I was starting to hear a 'tic'. Oh, oh I think to myself.
This morning I look under the hood for something obvious and find my dpfe valve. Both hoses blown off, melted, and the back cover of it missing. So, I think...Perfect, there's my tick.

I stop by the vehicle graveyard and get another dpfe valve and plug it in. Good to go....Not.

My truck keeps getting louder thru the day, so tonight I check for gasket failure. Nope. Under the truck I go only to find a cracked header. So, motor will be lifted this weekend (After pulling the front diff out to get at the motor mounts) so I can get the header off and take it to a guy I know that is a wizard welder. I sure hope he can fix it, as headers for these trucks are extremely difficult to find. You find them, they are expensive, and made out of a thin gauge steel.

I'm still stumped on the not trving past 4500 in 3rd at wot though. I really hope its not a exhaust back pressure issue.

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What size is your hot side (not a/r) ? And cold side ?

 

I do remember them making a metal body dpfe. Might be an easy grab at the junk yard.

 

Sorry to hear about the challenges with the exhaust leak but I am sure you will get it back up and running and sort out the tuning issue...

 

Yea, Once I had the motor lifted and header off I could clearly see where the header had been crimped also when the exhaust shop heated and bent the pipe over.
Its in at the welder now, and then off to be re-coated. The welder is going to cut the crack and crimp restriction out, then form a patch for it.

The turbo is a t3/t4 hybrid .70 76x68 .70ar 68mm cold side. It was spec'd for fast spool with a max of 550rwhp. Its a small hot side, but being that its rear mount (less volume in the cooled exhaust) and I wanted spool at lower rpm's for the street to get my 4700lb pig moving its a good fit. Bullseye power was really great to deal with.
So, once I get the header back on, I'll turn the boost down for the winter.

I've also been eyeing up installing a snow performance stage 2 w/m kit I've had laying around from a different vehicle. I had hoped the inter-cooler would allow me to hit my target 12lbs boost with no issues, but maybe scaling my goal down to 10 and adding more timing will be the smarter way to go. While my truck is waiting on its header I'll start finding places for tank/pump/controller.

 

Well, motor came out........ again.
Took out the thrust bearing. that took out the crank. pistons were collapsed slightly, and were also too small for the bore. Oh, and a few bent rods. keep in mind the rods and pistons were forged. laugh? cry? both?

So, detonation caused the collapsed pistons. no question.

Block took some slightly larger wiseco forged slugs, forged rods, and another cast crank.
I sent the converter in to have a few thou taken off he length as there was so little space between the flex plate and converter I thought that could have had something to do with the thrust bearing going out.

Motor is back in, and as I was tuning, I could clearly see he motor was pushing more air. I added a vampire knock sensor. wired it to an analog input on my sct tuner. Awesome, showed me exactly the rpm and load where I had to much timing.

As the tune matured, I couldn't keep the boost at 6lbs. I'd hit 14 labs if I wasn't careful. back to the exhaust shop to have my waste gate plumbing re-done. bigger pipe leading to it, and made sure the hole cut in the main exhaust was plenty big. Issue fixed. 6-7 labs boost, rock solid.

Anything past 6lbs and I'm pulling to much timing to avoid detonation. water meth install next.

Motors holding up great this time, and I'm being careful not to hurt it again. I don't know how guys just throw stuff together and it makes big power. truth is, its really easy to break stuff with boost.

 

How do you like the J&S? Do you have it actively pulling timing? I've had my eye on one for a while. It might be crucial to keeping the jeep alive if I ever get the turbo on it.

 

I'd highly recommend it for tuning. you really need an active tuning method (I added my j&s output to an analog input of my sct for logging. this gives me the rpm and load that the knock occurred. I pull a degree in the areas showing anything above very minimal lock, and log again. I think I get some false knock with the forged pistons. but you kinda get a feel for it.

When I stated with the j&s unit, it was trying to pull so much timing that my check engine light would come on saying I had a coil issue. lol. Funny thing is, I couldn't hear the knock. it was too much timing, because when I retarded timing in those areas the knock went away. check engine light doesn't come on anymore either.

I don't currently have the sensitivity high enough as I'm looking or a sweet spot, but am going to keep t active all the time.

I'd highly recommend this product. I'm only using 91 octane, so this unit really shows where the limits are as far as timing goes. yes, I agree that this unit does save motors. I see no reason for a dyno tune as I know I am at the limits of timing/boost for my application.

 

The beauty of the unit is that it retards only on the cylinder that's knocking. Where you may pull 2 degrees from your timing map, that affects all 8 cylinders. If the J&S pulls 2 degrees, it's only going to do it on the cylinder(s) that knocked, allowing the other cylinders to continue on at higher timing undisturbed, as long as they behave.

Some people really lean on the timing once they build some trust in the box to do it's job, finding they have more power then without, even with a carefully optimized tune.

My biggest problem is tuning. I was going to use megasquirt, but I have to pass an OBDII inspection yearly, so I may need to spring for the SCT suite. HPT doesn't support JTEC pcms. I've been playing with the megasquirt on the fueling side and a spoof box for the injectors and if I keep my tune tight I can keep the check engine light out for a few days. There's little hope of ignition control without adding a wheel to the engine. I've got a superchips that gives me a few tunes to play with as well as a global timing retard but for boost the J&S sounds like the ticket for staying out of trouble.

 

yes, the only thing to be careful of is the false knock. The unit works very well, and I would consider the the safeguard unit invaluable in tuning. I'm hoping to get the sensitivity just perfect and use it all the time. I just don't want it retarding timing under false knock conditions.

 

What great journey, did it all come together as hoped in the end..?

 

It's been painful. I actually have the truck running really good, although I have what I think is a rear main seal leak. It drips on the exhaust and stinks. Looks like I'll be pulling the motor again. At least the crank is tight and I cant pull it back and fourth. It's been an expensive, but great learning experience. Interesting thing is, thru all the issues the rear mount turbo setup worked perfectly.