how much HP can i put on the LLY, before i need to start thinking about upgrading engine parts. I've heard some people running up to 500RWHP before changing anything. I know i will have to upgrade the tranny. Any thoughts?
Question: D-max HP
- Thread starter maxpwr69
- Start date
SOme make it longer than others. I would say you are fairly safe from 500-600 RWHP after that it will be time for rods and pistons.
That sounds bout right. The only reason i ask is because i have a friend that just blew his ford up (big surprise). I think he said he was only making 375RW. I really wanted to give him crap about it, but that has to suck. Wouldn't wish it on anyone, but it was pretty hard for him to tell me about. He knew i wanted to say, shouldn't have bought a ford. 
375 RWHP for a 7.3 Ford is a big number. They just aren't that durable of a motor for huge power. And if it was a 6.OH NO then it was just a matter of time before she went pop.
No it was the 7.3. i believe it was a 1999 or 2000. apparently that was right before ford went to the bigger/stronger rods. He said the date they changed them was november of 99. his was dated in october. Damn the bad luck.
There's a local 7.3 at 680hp on the stock bottom end and an S475. Runs low 7s in the 1/8th and pulls with it. He took 3rd in the Top Truck Challenge at the OBX Pro Diesel Challenge.
Back to the original question there are ALOT of guys running around at 500hp on LLYs. You can get that with a lift pump, shim and tuning. Then there are alot of guys running around at about 600hp with a turbo uprade or nitrous. And there are still other trucks at 700hp on stock motor. There's not a set hp number that causes things to fail, it all depends on the tuning and mods you use to get there and some on luck.
i personally think alot has to do with how it gets driven. most guys dont get to the track or build there truck for "racing". if your not foot to the wood 90% of the time i think you will survive alot longer than most. jmho
That is of course very true as well and I thought went without saying. Hell a stock trans will survive a 500+hp truck if you keep your foot out of it - but then you aren't using the 500+hp so what's the point of having that tune on there. I lived 5 minutes from a track that was open 2 nights a week and drove my truck like I stole it almost everyday - my stock motor didn't last me all that long.
Yeah it's pretty comon to see 7.3's over 500 RWHP
. I beleive they are even more common place then Cummins and Duramax's in the 500-1000 HP range. Only bad 7.3 I have ever really seen is Zanes truck.the point is i know full well the risks of having a big tune, and i also know that if i blow the motor tommorow i would be rebuilding it, but i also know that the tens of thousands i would need to spend on it is not in my budget now. so i dont drive like i stole it, because i didnt
. i pay dam good money for it and refuse to deliberately destroy something i work hard to pay for. do i have fun once and a while sure just like the next guy, but my home and family come first. you have a business that entails tuning and trucks and need proof of your abilities so you have a return on your investment in a way. i dont. i fix the crappy job gm does with building them
Is there a difference between running your stock parts engine hard for a quarter mile and running it hard for sled pulling or towing?
It seems like oil and coolant (mostly oil) temps are not much effected by shorter quarter mile stuff? But high cylinder pressure (especially high cp where it should not be) can definately happen in shorter runs?
It seems like oil and coolant (mostly oil) temps are not much effected by shorter quarter mile stuff? But high cylinder pressure (especially high cp where it should not be) can definately happen in shorter runs?
Is there a difference between running your stock parts engine hard for a quarter mile and running it hard for sled pulling or towing?
The Million dollar question, I think sled pulling is harder on parts due to the load put on the driveline and motor. But other will argue draggin is harder on parts. Who knows?
The Million dollar question, I think sled pulling is harder on parts due to the load put on the driveline and motor. But other will argue draggin is harder on parts. Who knows?
i think towing is tough for sure on trucks, but your never 100% throttle start to finish making max power.
truck runs good on my 590hp tune, but i only use it for track and sled. or then i miss postion 4 and go right to 5 hahaha
Wow, i must be bad luck for ford guys. Just had another friend that blew his 7.3 up. Bad part is he didn't have a tune on his yet. He had just bought one for it and had not put it on yet.
Well, it's good to know the dmax is holding up to what you guys are doing. I don't drive mine like i stole it either. Take it to the track every once in awhile to show up the rice burners. Boy they really don't like it when a truck beats them. :happy2:
Well, it's good to know the dmax is holding up to what you guys are doing. I don't drive mine like i stole it either. Take it to the track every once in awhile to show up the rice burners. Boy they really don't like it when a truck beats them. :happy2:
super diesel
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Some I'm sure will argue this point but the majority of experience I've had is that the tuning and where the torque is made makes a little difference (but torque is torque in the end). At around 575 or mid 1100s on the torque, I've seen the rods bend (from compression test results, however LBZs are slightly better but can't comment on the LMMs). ALL seem to run well afterward for quite some time, but the damage is done and it's a time bomb now unless the bending was extreme (windowed block instantly instead of latter). Maybe we can cross the 650-700hp range with out going into the damaging torque area and live? Don't know. Compression tests don't lie. I also found that in most cases, by the time studs are needed, so are rods.
As for 7.3s. Been around quite a few. I know most bottom ends don't live past the 400hp mark unless strengthened up (P.M. rods models were the worst for failure, some don't make it past 350hp). Some with the better rods have even seen 500hp for a very short time with ugly results. If any are wondering, contact Tad at Elite (close to me). He'll let you in on the skinny.
As for 7.3s. Been around quite a few. I know most bottom ends don't live past the 400hp mark unless strengthened up (P.M. rods models were the worst for failure, some don't make it past 350hp). Some with the better rods have even seen 500hp for a very short time with ugly results. If any are wondering, contact Tad at Elite (close to me). He'll let you in on the skinny.
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The 7.3s Also need a girdle(s) to help keep the block from cracking/splitting in two down the middle like the 5.0 liters in the mustangs at higher hp levels
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