12ht Running Hot

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johnnyporp

johnnyporp

10 Year 15 Year
Joined
Apr 23, 2006
Threads
63
Messages
206
Location
BEND ORYGUN
Ok background I have swapped a 12ht in to a 1988 fj62 and have been running great for the last 3 months. However, I have installed a ETG (brand: glowshift ebay) about a 1.5 months ago post turbo and have noticed that I run 7-800 around town and have spiked 12-1300 at 2500 rpm with out much foot into it at all. This concens me in that what i have gained from this board is that I should figure I am running at leat 200 cooler post turbo. Is this normal or am I playing with 3 mile island? Any help advice is always much appreciated.
What I know
Specs: 12HT A440 95k miles
Etg Post turbo
Shimed waste gate 4mm
what I don't know
Boost pressure
how my wife drives when I'm not in the auto
the mating call of the Wookie
 
johnnyporp said:
Ok background I have swapped a 12ht in to a 1988 fj62 and have been running great for the last 3 months. However, I have installed a ETG (brand: glowshift ebay) about a 1.5 months ago post turbo and have noticed that I run 7-800 around town and have spiked 12-1300 at 2500 rpm with out much foot into it at all. This concens me in that what i have gained from this board is that I should figure I am running at leat 200 cooler post turbo. Is this normal or am I playing with 3 mile island? Any help advice is always much appreciated.
What I know
Specs: 12HT A440 95k miles
Etg Post turbo
Shimed waste gate 4mm
what I don't know
Boost pressure
how my wife drives when I'm not in the auto
the mating call of the Wookie
Click to expand...


The easiest answer is usually the fuel. Does the truck blow black smoke? It might be useful to turn down the fuel a bit.
j
 
No black smoke at all, White on a cold morning if not plugged in but no black.
 
You shimmed the wastegate without a boost gauge?

Be careful. That could lead to this ->:crybaby: .

Good luck to you sir. Would Brownbear be able to help you?

Hey, now that our swaps are complete we should get together for beers and Cruiser talk.
 
Ahhhhhhh

NOT SO GOOD EH.. I was under the impression that is was a little free power. I will fix that situation tonight and start from scratch and get a boost gauge. I really don't want to cause any excess $$$$$$ pain. Beer and cruiser talk sounds good. Your rig is looking good.
 
johnnyporp said:
NOT SO GOOD EH.. I was under the impression that is was a little free power. I will fix that situation tonight and start from scratch and get a boost gauge. I really don't want to cause any excess $$$$$$ pain. Beer and cruiser talk sounds good. Your rig is looking good.
Click to expand...

It can be nearly free power, but you need to know how much boost you are producing. Then, when you turn up the fuel a little you get more power. You need a pyro (EGT gauge) for that.

Turning up the boost pressure gets you more oxygen into the cumbustion chamber. More oxygen means that you can add more fuel and get more power.

:cheers:
 
johnnyporp said:
NOT SO GOOD EH.. I was under the impression that is was a little free power. I will fix that situation tonight and start from scratch and get a boost gauge. I really don't want to cause any excess $$$$$$ pain. Beer and cruiser talk sounds good. Your rig is looking good.
Click to expand...

Chances are if the wastegate is at stock funtional settings you will be boosting somewhere between 5.5-8.5psi. Shimming the wastegate 4mm will add a few pounds to this. If anything, when you remove the shims you will likely see an increase in EGT's...which is the reverse of what you want.

As has been mentioned, it is good to know what your stock boost is before playing with it. Then you have a datum.

In all cases where I have shimmed out the wastegate (with EGT and Boost gauges installed) I have noticed a fairly good drop in EGT's on WOT. I have still been able to get the EGT's up really high with the boost upped to 10.5psi under sustained load, and therefore have seen no need to add more fuel.

Increased boost on daily drivers in my experience (two 13BT's and one 12HT)...increased engine response, reduced smoke, much harder to get EGT's into the danger zone.

Of course an intercooler would give enough room dump in that fuel;-)

hth's

gb
 
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