Performance engine parts

[Pearl_Diesel]

All I know is that it's not good when the valve goes through the cylinder (RIP 7.3L )

 

[FordGuy100]

Honestly you guys, I dont see what the big deal about the high rpm's is. I think we could save a lot of headache if we try to shoot for good power...at lower rpm's. Whats wrong with the peak torque around 1900rpm's? Turning these things past 3800rpm's can be done, but its going to take a ton more work to get it to do so.

All I want is to be able to haul this tractor and trailer I got now (around 6000 pounds) and not have to be WOT all the time.

I say keep the power down low, its real nice (I was going up a bridge coming from Salem getting onto highway 22 headed west. It had rained with I was going up. I hammered it in 2nd from about 1100rpm's and broke them loose all the way up. Once the tires got going they were still spinning at 3/4 throttle. That was with the load I described ).

 

[FordGuy100]

And Russ, if your anywhere around....to do the cam instal, do you need new lifters? Or just re-use the old ones? And since I have 7.3 rockers/pushrods, should I use my 6.9 or 7.3 pushrods with the 7.3 rockers?

 

[typ4]

Your lifters will be fine, pushrods are all the same.

 

[Pearl_Diesel]

I agree with you, there is no need to make these engines turn excessive RPM's. We're trying to build a good power street truck, not a screamer. Just because you can handle the RPM's for a 1/4 mile doesn't mean you can handle them for any longer. If I want something to turn that fast, I'll swap in a two-stroke Detroit.

 

[Pearl_Diesel]

Instead I want something that I don't have to put a catch pan under every night so I can reuse the oil in the morning. Something reliable, but still with a little bit of gittup.

 

[FordGuy100]

I'm not saying dont do the high rpm's. I guess what I'm trying to say is everthing is going to have to be gone over that much more for the higher rpm's. Lower rpm's means you can have a little leaniency in things. With high rpm's you gotta balance, make sure everything weighs the same, no valve floating, ect. 3300rpm's is good enough for me. With the right gears it would be real nice

 

[Pearl_Diesel]

Yeah, but I just want to build this truck for 35's, able to still pull a gooseneck, and not have to go into low range to go up a hill. Kinda like a mud-tow-recovery. Not a mudder, just there whenever somebody gets stuck. And enough power to rip the front end out from under whatever's there .

 

[Pearl_Diesel]

No need for excessive wheelspin, just enough to get the ball rolling. I just don't like the whole rpm idea cuz there's that much more that could go wrong

 

[Pearl_Diesel]

Btw, that truck looks real nice. How much would you give for a rebuildable ZF-5? the only problem is the reverse fork is bent. All the forward gears are rock solid.

 

[Pearl_Diesel]

If it had reverse I would reuse it in a heartbeat. My newer trans feels like shifting a 60's two ton. Lotta slop there.

 

[Optikalillushun]

to make decent hp numbers u do need to spin rpms (at least in the gasser world) like 3500-4000 (and still making power not falling flat after low 3000s) for an IDI i would be ok with. i was just wondering if that cam made the rpm a little more broad and if it would utalize the GM pump springs more efficently.

 

[Pearl_Diesel]

You've got a point there, if a gas makes 200 horse at 5500 rpm, when a diesel makes that at 3000, what kinda horsepower would that diesel make if it could spin that fast. But then again, who knows what happens to the torque curve during all that?

 

[ameristar1]

Y'all know I was playing around with dyoung, since he's our resident "rev her till she blows|" test pilot. Most of the racing diesels like the Audi R10 LeMans racer and the Renault HDI don't go past 4500 rpms, and a stock, unbalanced bottom end is not going to take that for long.

Optimizing the cam profiles in several flavors will take care of that. Not everyone wants just a bottom end torque motor and that should be catered to. I want my motor to keep pulling to 4400-4500 rpms, just because of what I am going to do with it. The main thing with most of us is that the motor doesn't hit the wall before the governor kicks in.

 

[ameristar1]

You've got a point there, if a gas makes 200 horse at 5500 rpm, when a diesel makes that at 3000, what kinda horsepower would that diesel make if it could spin that fast. But then again, who knows what happens to the torque curve during all that?

If the hp and torque curves are the same between the gasser and the diesel, because of the higher compression ratio and the energy in the fuel, the diesel will outperform it. Think of it as a 10 to 1 compression gas motor going against a 21 to 1 gas motor, if you could find a high enough octane fuel to make it run.

You can build a diesel to spin that fast; the pullers do that all the time, I think Double Overtime with that mechano Stroke takes his motor to 7000rpms in a pull and 1800hp.