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Discussion Starter #1 (Edited)
Hey guys, its been quite some time since I've been on this forum. I got my Banks kit installed on my truck and it runs great, but I have a few questions. The kit I bought was on e-bay and was pretty rough when I got it. The compressor housing was cracked due to shipping and the seller ended up getting me a rebuilt turbo from turbo supply. I am not sure if they modified the turbo at all (it is a banks casting turbo) but I am able to get about 12-13 psi out of it at full bore. Right now I don't have my EGT gauge (wire on order) or Tach hooked up (don't have magnets for flywheel) but I was wondering if that was a dangerous amount of boost. I've read that the kit is only supposed to make about 9-10 psi... Also, on the highway running about 70 mph, the kit is making about 5 psi. The truck is an 86 military blazer with 3.73s, a th-400, and 35" tires. I had 4.10s in it, but it felt like it was revving too high, although it could just be me. Is this too much boost for a sustained distance? I feel stupid for not getting the EGT gauge working sooner but I am not too worried about high temps. The motor doesn't blow any black smoke and I only turned the pump a 1/4 turn when I put the turbo on.

On another topic, after I installed the kit, my truck got much harder to start in the cold. I don't know if this is just the glow plugs getting old or not. The truck has about 80k on it and I don't know if the glow plugs are orig. since it bought it with 68k. I am looking at replacing the plugs with AC Delco 60Gs, are these the best? Also, the glow plug controller on the truck was bypassed by a manual switch before I bought it and it seems to work alright. Is this an alright setup and for how long should I be holding the glow plugs on so I don't burn them up? I read that the 60G plugs are self-regulated, but I am trying to be careful.

Any help would be appreciated, THANKS!

Here is a pic, the jeep is my other toy and the blue one is my roommates rock crawler...

 

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From what ive read the most boost you want to make on a stock 6.2 is 10 psi. Once I get my turbo set up on im gonna run 9 just to be one the safe side. ; )
 

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10 psi is probably the max on a stock 6.2. with marine or lower compression pistons you could run higher.
 

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12 psi is all right, but that's the maximum. Don't run any more boost than that. Anything higher is a bit risky.

You need an EGT gauge. Don't run it hard without one even if the truck doesn't smoke black...

60G plugs are indeed self limiting. With those plugs you can hold the button on as long as you want. With other plugs (9G or 11G) you can burn the plugs out if you hold them on for too long (8-9 seconds is the max). 60G plugs are a must for a manual glow plug setup (other types of plugs are all right as well so long as they are self limiting).

Neat trucks in the picture! :)
 

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your boost is ok, but dont let it go over 12lbs of boost at wide open throttle, and only for short amounts of time. cruising speed should be lower than 12, 5 is just about perfect. other than that, 60G plugs, and you either need to regear badly, or get an overdrive. at 70mph with 4.10's and 35's you were turning 2700rpm's. this engine is very happy at 1800, not so happy at 2400, and mad at you above that. if you want to stay with 35's and stick with a non overdrive tranny and get to 70mph, you will need 3.42 gears. turning 2300rpms at 70mph then. if you go with an overdrive and stick with 4.10's, you will be turning about 2000 rpms at 70mph.
 

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Your boost levels are just fine. I would be very careful with the trottle until you get your egt gauge, you'ld be supprised at what those #s could be.

I would stick with the gearing you have it sounds like a good setup to me. If you drove 10hrs at a time at 70, then it would be different but for all-around what you have sounds good. Some guys drive their 6.2s at 2500rpm all day w/ no problems. So I wouldnt be worried.

I think that you sould probably replace your glow plugs, if nothing else you will know how old they are, and wont have to worry about them for a while. 60's are the way to go, but really any self limiting plug will work fine.
 

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Discussion Starter #7
Thanks for the advice guys. I really don't want to go back to a lower gear setting since the truck is a real dog with the lower gears all the time (and I already had the gears laying around). Unfortunately, I don't have the money/driveshaft length to go with an external O/D. I also, don't want to stick a 700r4 behind that motor, I've heard nothing but bad things about their reliability, especially with a 3 ton truck. Most of the time on the highway I end up going about 60-65 mph, which is a bit more realistic than what I mentioned earlier. I think this week I am going to change out the glow plugs, I just wish we weren't getting between 10 and 15 in of snow today!
 

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Discussion Starter #8
Now that I am thinking about it, the gearing in my truck couldn't be too bad. Stock it came with 31s and 3.08s which puts me at 2200 rpm at 66 mph, now that same rpm puts me at 61 mph. I figure I need the extra leverage anyway considering how much the damn tires weigh :)
 

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sounds like a good combo of gear and tire. have you checked what fuel mileage you get with it?
I'm guessing your banks turbo doesnt have a wastgate on it? no way to adjust boost if it doesnt', unless you add a pressure relief valve in the intake somewhere to vent at 10psi.
 

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the banks turbo's are non-wastegated, although I have read that there is another turbo that is a direct swap that has a full wastegate, read about it on
www (dot) the diesel page (dot) com

If your truck still has the original military starting system, then you have the wrong Glow Plugs. the plugs you will need are Wellman 070's you can get them from www.ssdieselsupply.com or "indusa" on ebay. The cucv's stock wiring sends voltage to the GP's through a resistor on the firewall to allow for jump starting through the slave cable. the resistor allows ~18v through and drops it to 12v as is heats up. the civilian plugs will not live under these voltages.
 

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Discussion Starter #11
I have already converted the truck to 12 volts since I replaced the starter a few months back. Thanks for the info!
 

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Discussion Starter #12
Well, I got the EGT gauge hooked up and the numbers look just fine. Unless there is something wrong with my pyrometer sensor in the manifold, my around town numbers are 150 at idle, 300 -400 normal driving and 600-700 if I am getting on it hard. On the highway I see around 500 at about 60 MPH. I haven't put a load behind it yet, but I think I may be able to crank the pump a bit more since the EGTs are so low.

Also, this is most likely a stupid question, but would 14 - 15 mpg seem about right for highway driving on a truck like this?

th-400
35" sampers
3.73 gears
14bolt full float
3/4 ton 10 bolt
6" lift
Just around 3 tons total

The gears and tires put the truck just around stock with the 3.08s according to my GPS since my speedo is only reading about 1-2 mph off around 60 mph. I am wondering if it is the weight and size of the tires or just the size of the truck... Oh well
 

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86cucv;1681258; said:
Well, I got the EGT gauge hooked up and the numbers look just fine. Unless there is something wrong with my pyrometer sensor in the manifold, my around town numbers are 150 at idle, 300 -400 normal driving and 600-700 if I am getting on it hard. On the highway I see around 500 at about 60 MPH. I haven't put a load behind it yet, but I think I may be able to crank the pump a bit more since the EGTs are so low.

Also, this is most likely a stupid question, but would 14 - 15 mpg seem about right for highway driving on a truck like this?

th-400
35" sampers
3.73 gears
14bolt full float
3/4 ton 10 bolt
6" lift
Just around 3 tons total

The gears and tires put the truck just around stock with the 3.08s according to my GPS since my speedo is only reading about 1-2 mph off around 60 mph. I am wondering if it is the weight and size of the tires or just the size of the truck... Oh well
yeah, 14-15 seems about right for a new turbo setup on that monster...once you get used to the power it will go back up to where it was :D

i would run the pump up a little more, but i am a black smoke junkie :cool:
 

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That seems a little low to me. I have a 85 4x4 burban and I got 16 mpg towing 2000 lb trailer. Burban has an aftermarket banks turbo. My tires arent as big but it is a heavy suburban.
 
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