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quickv6
03-05-2005, 22:47
How much Boost can I run with a Bone stock 6.5TD?? I installed a guage and is around 10-12 PSI. Spikes to 15 and fallls right back to 10-12. Truck pulls like a raped ape towing but I see 6 and 7 psi stock all over the board. Dont want to tear it up.

Barry Nave
03-06-2005, 03:14
Welcome,you just been bitten by the Dieselpage bug :D With out having a cool-charger,be it water Inj. or an air to air system,I would keep max boost limited to 10psi under a load. Running unload, say around 65mph you'll see 6-7psi.
You must have a boost controller installed and may not know it, for you would not see the type of boost psi that you are seeing.Is this truck new to you? first 6.5? If so there could be hidded inprovements from last owner. What do you see on the EGT. if installed. Should be low if your just stock. More boost has a EGT cooling effect with out adding more fuel. Your next step would be a chip or reflash,high flow air cleaner and EX.
Always good to know year,milelage and history of truck.
Just now seen your truck on another topic ;)

quickv6
03-06-2005, 06:51
This is my first 6.5. I love this truck. The only Mod that I have done is added air intake and #9 resisitor. I have boost gauge but no EGT. I have had the ECU out and the chip is stock. I pull an avg. GVW of 19,600lb with this truck. Sometimes slightly more. It pulls this load so much better than my 2002 gas job did. I even sold my newer truck and kept this one. So yes the bug has bit me. I would like more power. So I am looking to build a new engine for this truck that can handle more power.

rameye
03-06-2005, 07:03
I was just about to post this question as I'm examining whether my turbo is actually functioning properly.

According to the GM service manual. They state boost pressures of around 2psi during hard accleration is normal.

According to my tech 1 the most boost I'm getting is 4.3 psi @ WOT.

Questions for anyone....

What should stock boost be?
Is reading boost pressure thru your scanner accurate?

Thanks.

Barry Nave
03-07-2005, 02:26
Quickv6
These boost numbers are what I see when bypassing the wastegate solenoid. (failed unit as of now,need R&R) I wonder how you can get thouse boost reading running a stock chip.
My stock boost max was 7psi.under load,Norm. was 3-5psi. First up grade was a Banks kit. Chip,air cleaner mods,boost-egt gage and EX.
Boost 7psi,load 10 max.
Rameye
You should see more then what your reading.
I guess only a boost gage can give true readings?

Barry Nave
03-07-2005, 03:30
Look at 94
smokesssssssssssss

[ 03-07-2005, 10:03 AM: Message edited by: Bnave95 ]

rameye
03-07-2005, 15:44
I question the statement in the service manual which states "2 psi under acceleration is normal".

I mean why bother?

Just wondering what other stock set-ups are getting.

quickv6
03-07-2005, 16:45
Originally posted by Bnave95:
Quickv6
These boost numbers are what I see when bypassing the wastegate solenoid. (failed unit as of now,need R&R) I wonder how you can get thouse boost reading running a stock chip.
My stock boost max was 7psi.under load,Norm. was 3-5psi. First up grade was a Banks kit. Chip,air cleaner mods,boost-egt gage and EX.
Boost 7psi,load 10 max.
Rameye
You should see more then what your reading.
I guess only a boost gage can give true readings? I guess the truck could have a chip. I did not install one. I replaced the turbo about 6 months ago with a GM8. I would say that the fella before me has tricked somehow. Will it live running these boost numbers?

Barry Nave
03-08-2005, 03:54
With the Banks chip and JK boost controler I am seeing the same as you are. 15psi boost, only see it now and then when TC locks up and rpms drop while under load. When I see this I just turn on the water injection.

radrecon69
03-08-2005, 04:07
I have a 93 and running a Heath boost controler @ 65 I see 4-5 lbs of boost crusing and at 70 I will see 7-8lbs of boost under acceleration I see 10-12 lbs

Rick

quickv6
03-08-2005, 08:59
Is 10-12 psi boost too much for a bone stock 6.5TD? Will it kill my engine? I did find the problem today. The wastegate was hanging up. took off the rod and got it moving real nice. Now the boost is like 4-5 psi max. maybe 2-3 under light accel. Now truck has no damn power. I guess I should have left it alone. The answer to the max boost question will tell me what I need to do.

cruzer
03-08-2005, 11:28
EGT's are the killer.

I run 13-15psi boost pulling a load w/stk pistons, but I have componets to keep the air charge and engine cool. Cooling the air charge helps keep EGT's in check.