Losing boost at 6400rpm. Help!

[suprahero]

Jdub, here is how they came out when I degreed them before I installed the motor. http://www.supramania.com/forums/showpost.php?p=1025987&postcount=899
When I tried cranking the car, it wouldn't crank, but I ended up having to put a lot of fuel in the tune to get it to crank. By the time I did this though, I had put the cams back to "0" .
I will reread the link you posted and then see if I can get a shop here locally to help me redegree them. It's hard with the 1jz head to degree because the lobes cover up the bucket shims and you're suppose to have the dial pin parallel to the valve stem, but I call bullshit. There's no way to do it.........plus everything on the engine is aluminum and it's hard to find something for the magnet to stick too so it doesn't move. The timing cover is metal, but it isn't flat...........:aigo:

Thanks for the help again. I'll try this probably tomorrow night on the dyno with adjusting it a little at a time. I'll make sure and have race gas in it just for added safety.

 

[jdub]

The tuner needs to be listening for knock with a set of "ears". Keep in mind race gas is going to delay the onset of knock and is going to give a false sense of security when the cams are adjusted. I guess an initial hack with race gas is fine, but the final cam adjustments need to be done with pump gas...unless you plan on running race gas daily or the Stinger has a dual fuel/timing map capability.

Keep in mind, to reduce overlap, you advance (+) the exhaust cam and retard (-) the intake cam.

It looks like to me something went wrong when you degreed the cams

And this statement is a bit confusing:

I know last time my exhaust was retarded to 8 degrees, and my intake was advanced 4 degrees, and that was adjusting them on the dyno.

That's the opposite of what you said earlier in the same thread. It doesn't make sense...those settings would create 22 degrees of overlap

Find a place on the head with convenient bolt holes and make a steel plate that you can bolt to the holes and is parallel with the top of the head. This will let the magnetic base stick.

Re-read post #420...there's a couple things I'd like to know (damper, turbine wheel diameter).

Jay - this has to be done in a sequence for the results to be valid and get an accurate starting point for the subsequent ignition timing and tune. Shortcuts are not going to end well. I know you're frustrated (and probably don't want me to bring this whole cam thing up again), but take the time to do this right...it's the only way to eliminate it as a possible problem.

 

[suprahero]

I don't know what the damper is. I'll have to call to see what the specs on the turbo. When you say turbine wheel, are you talking about the exhaust side?

 

[jdub]

I just wanted to know if it's a stock 2J damper or is it an ATI.

Yes, the turbine wheel diameter...the other side is the compressor

 

[buckshotglass]

I can only hope for this kind of help when I get close to running.
I wish I was Jay.

 

[suprahero]

It has the stock damper on it. I have a call in to Kyle, the guy I bought my turbo from, and when he calls me back, I'll find out what size turbine wheel it has on it.

 

[buckshotglass]

It should be stamped on the housing, Jay.

 

[suprahero]

I can only hope for this kind of help when I get close to running.
I wish I was Jay.

You just want my wife.........I don't blame you though.......:naughty:

I only hope I'm still driving my supra when you get yours close to being done. I may be in a retirement home by then...........:icon_bigg

 

[jdub]

It has the stock damper on it.

Alright then, that makes checking this even more important while your setting TDC:

It would be a good idea to check your damper once you figure out where TDC is. The damper index should be pointing at "zero" on the scale above the crank. This will be useful to set initial ignition timing after you do all this...just add/subtract degrees based on where the damper index is pointing with the #1 cylinder at TDC.

Stock damper have a nasty habit of twisting the rubber up inside and skewing the index. It can make setting your ignition timing a "challenge"

 

[suprahero]

I just got off the phone with Kyle and all he can tell me is it's a 67mm dual ball bearing turbo with a .68 rear housing. He is going to send an email to precission tomorrow to see if he can find out anything else.

Dave, the only thing stamped on the housing is "PRECISSION".

I may can remove the radiator and hydrofan and have enough room to degree the cams over. It is suppose to rain here tomorrow so I won't be able to do it then, but I may be able to take it to my brothers and do it. He doesn't own a supra, so he could afford to build a nice three car garage.

 

[buckshotglass]

I hope it says Precision. If them didn't check their spelling on the stamp, I'm worried.

 

[jdub]

It could be me just getting old thinking that the PT67 was causing the problem you're having to occur sooner...I was trying to figure out why. If the problem is identical with both turbos, the point is moot.

I was thinking the reason why the PT67 might cause that (from a restriction point) is a smaller turbine wheel. But, the PT67 turbine wheel (67mm) is almost the same size as the 35R...it's 68mm. The smaller A/R on the PT67 will have some effect though.

 

[suprahero]

I hope it says Precision. If them didn't check their spelling on the stamp, I'm worried.

Do you really want to get into a spelling war with me..............:icon_bigg

Jdub, I will do some runs on the dyno and compare them to the ones I've did with the 35r. I don't really want to do a lot of runs out on the street until I get some race gas in it. I'll post up the results soon. Thanks.

 

[jdub]

If you decide to change the cam timing, just be careful. Small increments

I'm going to be on my annual pilgrimage for the next few days to experience all the mean and nasty things that can happen in a 747 simulator. Won't have a lot of time to hang here till Wednesday night. Good luck!

 

[bigaaron]

Jay, send me your current ecu's tune file please. I'm interested to take a quick look at it.

 

[suprahero]

I switched my map sensor for the stock one just to see if it changed anything. I went down the road trying to do some datalogs, but the roads were wet and I couldn't get any traction in third. I tried several times and then went to the highway, but I got the same results. I tried easing into it, but just as soon as it would hit boost about twelve psi it would start skating. I was going to do it in fourth, but their was a little bit of traffic and I'd be doing about a hundred in fourth before I got to the 6400rpm mark. I'll have to wait until tomorrow or this evening when the roads are drier. I don't know why, but it seemed like it was pulling harder............maybe it's just my brain wishing like hell that it's fixed.

Aaron, PM sent.

 

[rakkasan]

I switched my map sensor for the stock one just to see if it changed anything. I went down the road trying to do some datalogs, but the roads were wet and I couldn't get any traction in third. I tried several times and then went to the highway, but I got the same results. I tried easing into it, but just as soon as it would hit boost about twelve psi it would start skating. I was going to do it in fourth, but their was a little bit of traffic and I'd be doing about a hundred in fourth before I got to the 6400rpm mark. I'll have to wait until tomorrow or this evening when the roads are drier. I don't know why, but it seemed like it was pulling harder............maybe it's just my brain wishing like hell that it's fixed.

Aaron, PM sent.

LOL, don't tell me I got it right! I hope so, and if it so, I won't bring it up a thousand times.....maybe a few hundred :biglaugh:. I hope it works Jay!

 

[suprahero]

Too wet to tell. I wonder what the difference is between the 1jz and 2jz map sensor? Does anyone know? Does anyone know how you can tell if the 2jz map sensor is bad? It has three prongs on it, but I wouldn't know what I'd be checking for.

 

[tissimo]

What would you be right about?

If the map sensor was bad I assume it wouldn't give a reading.

 

[rakkasan]

What would you be right about?

If the map sensor was bad I assume it wouldn't give a reading.

He's now runniong a 2J MAP sensor instead of a 1J. I think that there is a scaled difference between the two.....