Should be able to tell HP and TQ which should give me an indication if I'm better then stock or not. Should also be able to tell if its retarding timing due to detonation. Along with fuel curve. Do these trucks run a constant fuel pump pressure? Give or take I was expecting 10-20HP over stock.
CK5
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Which Roller Rockers Help?
- Thread starter nsxxtreme
- Start date
Should be able to tell HP and TQ which should give me an indication if I'm better then stock or not. Should also be able to tell if its retarding timing due to detonation. Along with fuel curve. Do these trucks run a constant fuel pump pressure? Give or take I was expecting 10-20HP over stock.
Unless you've dyno tested this rig before you did any work to it then you have no baseline to compare to. The HP/TQ numbers you see in the book are at the crank.
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before the rebuild it was running on 6 cylinders so would not have mattered. You can still get a general idea with 15-20% drive train losses.
Damn! I was about to bitch about a max difference of .004 between all 8 cyls.
I'm calling for some cyl pressure readings! Boy that would be another good indicator of what's going on with his compression. Then we can all argue about those readings and anything new that gets posted with 'em. Just warm it up, pull all the plugs, keep the throttle open wide and start cranking... hmmm... guess you could unplug the coil and put a compression gage in the spark plug hole while you're there...
Cranking compression is going to vary depending on the cam that's in the engine. For instance my engine is at exactly 9.489:1 and my cranking compression is 200psi. My stock engine was 205 cranking compression at whatever the factory compression ratio was which is supposed to be 9.3:1 but all the engines i've taking apart that were TBI it is closer to 8.9:1
Exactly, but I just think that if his motor really is 9.4-10.ridiculous:1 compression, and he throws in a cam that's "supposed" to be good for low end torque (thought I saw that claim in here somewhere), he would have a pretty high cyl pressure at low speeds... Says his machinist said to expect 160-180 psi... just curious if it's way beyond that now.
Just an update I ran my Truck through DEQ and found my problem.
The truck burned massive amounts of oil before the rebuild. What I ended up with is a non functioning clogged CAT. Replaced the CAT for $100 and now it runs SOOO much better. I still don't think I could make it up the highway hill in 3rd (or even do more then 50 mph) but at least things are running a lot smoother now. I won't know until next year when it gets warm out again.
Anyone know if they made a bolt on supercharger for this year truck?
The truck burned massive amounts of oil before the rebuild. What I ended up with is a non functioning clogged CAT. Replaced the CAT for $100 and now it runs SOOO much better. I still don't think I could make it up the highway hill in 3rd (or even do more then 50 mph) but at least things are running a lot smoother now. I won't know until next year when it gets warm out again.
Anyone know if they made a bolt on supercharger for this year truck?
Kenny78
1/2 ton status
HAHAHAHA
I dont hink that is the direction that you need to go. I rarely chew on somebody on this board but you could really benefit from
.Your never going to make diamonds out of horse crap.
Since your Cat was in such bad condition, have you repalced the O2 sensor with new engine? Even had it hooked up? What do the spark plugs look like?
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I'm still waiting to see the dyno numbers we were promised....
smalltruckbigcid
1/2 ton status
Greg he's been acting like a troll from the beginning, I wouldn't hold your breath
anyone know off hand what rockers a 76 K5 would need? Im staying 1.5, dont need anything more, just wanna eliminate friction everywhere possible. Whole engine is stock. I just need to know if its 3/8 or 7/16 stud, and self aligning or not.
Still working on that one, one thing at a time. Finding someone with a dyno that will work with 35" tires is harder than it sounds. A bad CAT would have produced horrible results and would have been a waste of a dyno run.I'm still waiting to see the dyno numbers we were promised....
I still intend to do this. I have been working with Brian from TBIchips.com who is extremely helpful and suggested the problems might be associated with the CAT. He also provided a link to a cheap CAT!!! This made a huge improvement. I previously failed a smog tests horribly, now the truck passes easily.
This is a side job so progress is slow. This truck is just a toy and never really driven except when towing the other toys. So be patient and I'll get there eventually.
Again appreciate all the suggestions and comments
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HAHAHAHA
Your never going to make diamonds out of horse crap.
Since your Cat was in such bad condition, have you repalced the O2 sensor with new engine? Even had it hooked up? What do the spark plugs look like?
It's not really a direction I intended to go but if I found a used one for dirt cheap I might be inclined to grab it, I just needed to know if they even made them so I know what to look for. I wouldn't spend the money on the cost of a new one. If I was I'd go with an engine swap to a newer motor instead.
02 sensor has not been replaced I have checked it and it appears to be working.
Spark plugs are fine nice golden brown.
The motor as far as I can tell runs great now. It's more responsive and revs much better. I doubt it will tow my boat up the hill any faster but I won't know for sure till next year because that is put away. My unscientific seat of the butt dyno tells me it's running much better and it will spin the 35's when I stomp on it. A dyno will still help check to see what the base numbers are I just need to find one that accepts this large of a truck. If anyone knows of one in Oregon please post.
