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Rytari
07-31-2007, 04:21
I have little egt thingy on my blazer and i would like to hear your opinion and ideas for it.

first of all, i know that egt:s above 1100 will kill 6.2d for sure, that i have learn from here. But what is the normal egt:s for highway driving, how high temps you can keep at all time.

i have 78 blazer w 6.2d/th700/np203/35"tires setup, geas are now 3.07, but on the table is wating 4.56 R&P:s for assembly. Engine has more miles than i can even imagine :) last summer i change timingchain, lifters, heads and injectors, also i made bigger air filter intake and 2,5" dual pipes.

Yesterday i change injection pump, old pump makes only black smoke( a lot, like a pulling tractor:eek: ) and vibrations. with old pump i get 1300 egt:s on hills and almost 1200 on 60 mph speed

New IP:s timing mark i turn slightly to drivers side for advanse timing.

now i have run some testdriving and what did i get... egt:s still going over 1100 when taking more power from engine, and in normal 50-60 mph driving i get mostly 900 from egt, and raises easily to 1000.

i think this high egt:s not too good, but how can i help myself now?

john8662
07-31-2007, 08:24
In all reality, the 1100 EGT limitation is primarily important when the engine is turbocharged.

In N/A, achieving higher EGT's is more common.

I all reality, it would be good to keep them at or below that temperature for the sake of the heads etc.

You can already see the advantage of having a properly working injection pump that is delivering the correct fuel amount for what the engine can burb. Obviously the old injection pump was over-fueling the engine leading to the large amount of black smoke it was making.

Most 6.2's survive just fine w/o knowing the EGT in Non-Turbo form.

Installing a Turbocharger increases the amount of fuel the engine can burn, which increases the cylinder pressure under a combustion event considerably due to the extra fuel being burned. So carefull consideration is taken into affect here.

J

Subzilla
07-31-2007, 09:47
Sounds like your new pump may still have the fuel metering screw turned up just a little too much. My Sub with 35's will run at 600ish on level ground at 60 mph. Yes, on the hills it will climb to 1000. The quickest way to counteract this is to downshift a gear. The engine will definitely strain in overdrive and dropping to drive will instantly help plus it is much nicer to the transmission as it will circulate more fluid during this higher demand time. The Blazer runs even cooler - smaller tires.

Rytari
07-31-2007, 12:58
in my rig, downshift not lower egt:s, maybe it will remain where it is, but lower it gets only when im lifting right foot from the floor... i think gearing my axles will do some good for it... now blaze is just too lazy when running on od at 60 mph.

main broblem is that can i run constantly this 900 egt:s or do i have to do something to lower it ( without loosing power), and what will be good way to do it..


http://static.petrisimolin.com/gallery/data/images/Rytari-blazec.JPG

Rytari
08-05-2007, 11:27
now i have driven some testruns with new 4.56 gears. engine runs now little cooler and egt:s on 50-60 speed stays somewhere 650-800, also i dont have to stand on the pedal for uphills...

best improvment that i newer had...