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Opinions needed - Performed Optical Bump

I noticed in one of your earlier post , your getting 15 psi boost, Without a "boost fooler or tune I have never been able to run more than 11psi without it throwing a code and defueling.
 
smokymtn65 said:
I noticed in one of your earlier post , your getting 15 psi boost, Without a "boost fooler or tune I have never been able to run more than 11psi without it throwing a code and defueling.
Click to expand...
since I swapped the GM-4 with the GM-8 style turbo and fixed the leaking intake gasket, when I put it to the floor on take off it will reach 15 PSI. I only have the wastgate vacuum connected on the turbo but I also know that my wastegate solenoid is bad. it will set a code if I go over 70 mph but I have never experienced a defueling that I'm aware of. not unless the PCM has been tuned and I don't know it! ( how would I find out ) anyway if I can remember to do it, I will take a video clip on my way home from work this afternoon on the dash gauges while pushing it to 15 :)
 
When i said run the high psi to test- i was not including the tank.
Tank is ok for a few psi, not much. And the low psi isn’t always enough to find the leak.

I’m too used to being able to easily drop the tank and inspect. Then with tank out hook the little hand pump onto the line where the tank connects. I Forget how annoying it is at home sometimes.
 
ok, I did the video on my way home from work. I know it's crappy with me watching other cars on the road at the same time but here it is lol.

I had the pedal to the floor until I started going over the speed limit ( DPS are always on this road watching ) as soon as I let off the throttle the engine light came on and I actually felt the power loss. I tried flooring it again and as you can see it just wasn't there. got to the house and checked the codes. had code 78 - wastegate solenoid. that I know is bad, I just haven't done anything about it yet

Boost output test
 
smokymtn65 said:
It will reset with key cycle. If your pulling a load you will notice the defuel more. Either you have to , back off the boost, build the boost fooler, or tune it.
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I'm wondering now that I can get full boost, if I were to replace the wastegate solenoid the PCM would regulate it and not defuel.
 
I'm also curious about the wicked wheel 2. I know I probably don't need one, but I was watching a video that Gingersnap customs made on the boost pressure vs drive pressure on the GM turbo with and without the wicked wheel. it makes sense to me to have a more efficient turbo, but who all has used one and what differences did it make under normal driving conditions. Like did the turbo spool up sooner or slower? did it save anything on economy?

I don't plan to buy one at least not anytime soon, I plan to hopefully find and fix the air intrusion this weekend and then start looking at the cooling upgrade. See what parts I can harvest for that from local salvage yards like the fan blade, new pump and I saw a write-up on using a thermo-electric fan clutch from the vans with the 6.5. that clutch I think will help with commanding it on with the AC and thermally controlled from a temp signal. then from there I may look at an inexpensive WMI setup, I read a write-up on one they built from scratch that had the ability to turn on under certain boost pressures and was able to save about 3mpg's
 
I installed a WW into My turbo, along with the rebuild kit.
The turbo does spool quicker right off of idle. It will not give You more boost pressure.
I made My own turbo master controller. It worked very well, but, it did drop the fuel mileage a mile or so to the gallon.
I removed it and did the repairs on the vacuum system.
I do however, pack extra electronic boost control components just in case one of them fails when I am on the road.
I also pack the home made turbo master in case it is something more serious, like the vacuum pump failure.
 
MrMarty51 said:
I installed a WW into My turbo, along with the rebuild kit.
The turbo does spool quicker right off of idle. It will not give You more boost pressure.
I made My own turbo master controller. It worked very well, but, it did drop the fuel mileage a mile or so to the gallon.
I removed it and did the repairs on the vacuum system.
I do however, pack extra electronic boost control components just in case one of them fails when I am on the road.
I also pack the home made turbo master in case it is something more serious, like the vacuum pump failure.
Click to expand...
I like the idea on the WW spooling up faster and sooner. I don't think more boost is needed at all, but just boost up sooner and have the PCM control it. I know the vacuum actuater on the GM-8 is a different setup than the GM-4 so I'm not sure if the vacuum solenoid can still regulate it properly, that I guess I will find out once I get the solenoid replaced. as it is now I normally see between 5 and 8 psi on normal take-off and stays around 5psi on a 60 mph cruise which is fine. I think the better part is the less drive or exhaust back pressure and lower EGT's
 
Will L. said:
I think $ spent on wicked wheel is better spent on a better turbo.
Wicked wheel is better than stock, but better turbo makes a much bigger difference.
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Yeah I know, I was just curious about it and wishing the WW was cheaper in price! I like what I'm seeing out of mine right now and for lower EGT's if and when I get to the last part, the WMI system that will do a much better job from what I've read. I just have to keep it in my head that I need to fix the problems first and then add the mods later to make it better lol..
 
That makes for a tough call, the WW or the better turbo.
I could not afford to get the better turbo so I went with the WW.
I am happy with that decision, but, the better turbo is in the wish list. It will happen, just going to take a little while.
 
Well. I got to test the fuel lines and found no leaks! But after about 20 minutes with having 15psi on the line by the lift pump toward the engine I saw air pushing through the IP into the clear return line!! Is that normal?
Also since I had air now when I put it all back together I wanted to prime the air from the lines by running the lift for a bit. Well when I bypassed the relays to run the lift. I discovered that the lift has power but is not running. Ahh 😨

what was the recommended pump to use instead of the OE diaphragm pump??
 
I think I’m going to have to settle for an OE pump for now since there isn’t anything else here locally available to keep my rig on the road. Then later I can do an upgrade and take my time with it
 
dbrannon79 said:
I saw air pushing through the IP into the clear return line!! Is that normal?
Click to expand...

Yes Normal. The rotary vane pump in the IP isn't leak free.

Keep in mind diesel can "vapor lock" as it will boil in a vacuum. The rotary vane pump in the IP sucks hard enough against any restriction and can literally vapor lock a diesel. So a working lift pump is why all the suggestions to a fuel pressure gauge...
 
Wait- what?
No air should go through the fuel system of any noteable amount. A bubble the size of a bb after running for 30 minutes getting trapped is ok. But this- no. That is way too much air in that video.
There is absolutely a leak somewhere allowing too much air in.

Either
1. clear line from the ffm to the ip and id the ip faulty, or pre ip air comes in
2. Pressurize system and find leak.

If the lift pump is identified as bad- replace it and continue examining. If not upgrading to a better lift pump, buy the AC Delco EP158.
 
To elaborate on how I went about checking for leaks was by disconnecting the steel line behind the lift pump. Threaded an adapter into the lift with a hose and regulator to my air compressor. Set the regulator to 15 psi and started looking closely at all the lines from the lift all the way to the IP. I didn’t see anything leaking at all. Only after about 20 minutes or so while the 15 psi was on the line I noticed bubbles flowing out of the IP into the clear return line so I pulled the air pressure off. Connected the fuel line back on the lift pump and went to prime the air I had forced in with the compressor out and found my lift pump isn’t working. In checking why I found there is power but no ground
When trying to prime the line. I put a jumper wire on the OPS which energized the add on relay to the lift pump. Tested the connection at the lift with a test light and had power but no ground.
 
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