Chevy1925 (James) Truck/motor build
- Thread starter Chevy1925
- Start date
im going to try both ways. Adam suggested more but i can see the plus and minus in either direction.
More would put more heat in the cylinders wouldn’t it? I’m thinking let the heat go out the exhaust. You’re probably running much more boost than Adam also. What fuel pressure, timing, boost, intake air temp are you seeing when you’re pulling the hills.
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i would think so but it also makes more power to the point of dimished returns. that timing im running i would consider "low" in comparison to what i ran on my 45% overs when the truck was a LB7.
i have not logged the truck while towing but uS i would imagine is close to 700ish as im about 75-85% throttle when pulling the hills and thats at around 2600-2700 in 4th or 2000-2100 in 5th which is 8ish degrees at either rpm. Boost is 45-48psi at 1200* in 4th gear at 26-2700rpm at WOT, at 75-85% throttle im at 37-40psi and 1100* in 4th gear at 26-2700rpm.
air intake temp is only measured at the air filter and its seeing 100-105* on a 95* day while moving. i have the intake blocked from engine heat.
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Found my laptop 
I would have it at 4.5* to 5* at 2000 rpm and 7* at 2800rpm with 1000us.
Have you tried dropping it down another gear and giving it some rpm. I would think you would want rpm about 3600rpm and see how much air that fan can pull.
I would have it at 4.5* to 5* at 2000 rpm and 7* at 2800rpm with 1000us.
Have you tried dropping it down another gear and giving it some rpm. I would think you would want rpm about 3600rpm and see how much air that fan can pull.
Off topic here but you guys pulling grades made me think of one I encountered over on this side of the country a couple weeks ago.
Adam might know the hill I am talking about outside Portsmouth, Ohio. Short hill but it’s a 19* grade both ways. Freaking insane.
Adam might know the hill I am talking about outside Portsmouth, Ohio. Short hill but it’s a 19* grade both ways. Freaking insane.
Found my laptop
I would have it at 4.5* to 5* at 2000 rpm and 7* at 2800rpm with 1000us.
Have you tried dropping it down another gear and giving it some rpm. I would think you would want rpm about 3600rpm and see how much air that fan can pull.
2000/20 works with stock doesn't work with bigger injectors..
For debate sakes... 100 over shoots double the volume with same rail...
Stock 2000uS at 20*
100 over 1000 @20°
Would be same.. on paper.. problem with bigger injectors is you can cool the cylinder off too much... due to how fast you can put fuel into it...
My guess ~75% of what stock would be would be sweet spot for the 100 overs. Fuel still has to burn in a close chamber
Which would probably change the area it's hitting on the table as well...
Joe on what road?
Haven't been on that stretch. Usually run 23 all the way down either to 52/7 or jump across into KY pending where I'm heading
the sole reason I took it was to avoid traffic on 52 going into Portsmouth.
Followed a roll back and didn’t think he was going to make it.
I may have it all wrong, but if you cut pulse in half you also cut timing roughly in half to maintain the percent of the duration being sprayed before top dead center.
If you're Injecting 10cc of fuel.. just because you can shove it in in 1/2 the original time... doesn't mean it burn twice as fast.
Exaggerated... But gets the point..
Using said 10cc volume say burn time is 3sec.. and stock injection time is 3sec.. we double our injector size which allows us to inject in 1.5sec same 10cc volume..
Burn time is still the same because volume is constant..
Exaggerated... But gets the point..
Using said 10cc volume say burn time is 3sec.. and stock injection time is 3sec.. we double our injector size which allows us to inject in 1.5sec same 10cc volume..
Burn time is still the same because volume is constant..
Do you really expect a newer truck to do the same as yours and then some while keeping everything in check like your asking from your current truck? I just don't see it happening I guess but maybe.
I feel if you buy a new truck, youll lift it, put big tires on it and tune it expecting it to put pull what you already have and I don't think it will keep everything in check like your already dealing with. You literally have all odds against you I feel like lol
From what I know, don't twins really heat the oil up pretty good any ways? Lol try a big single or just a 68stg 2 r or something. Hell idk, it just doesn't make sense to me why your making so much heat, do you have that clutch fan that kicks on sooner? Maybe that would be a helper.
I feel if you buy a new truck, youll lift it, put big tires on it and tune it expecting it to put pull what you already have and I don't think it will keep everything in check like your already dealing with. You literally have all odds against you I feel like lol
From what I know, don't twins really heat the oil up pretty good any ways? Lol try a big single or just a 68stg 2 r or something. Hell idk, it just doesn't make sense to me why your making so much heat, do you have that clutch fan that kicks on sooner? Maybe that would be a helper.
He’s done everything to keep it cool. The cooling systems on the newer trucks are a lot better. If I get the L5P up that way James you’re more than welcome to hook up to it and try it out on some hills before you make the purchase.
Generally speaking that's the jist of it... I highly doubt the hard parts would last long with fuel shoot in 1/2 the time at the same injection point..
I'm sure there's guys that can and have posted in extreme detail the difference.. and most would ha e their eyes gloss over reading it..:rofl:
Right ,but the l5P is not making 600hp towing and has alot more Management systems to pull things back where as James is literally just sending it with hsi right foot.