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quote:
I was watching the video of your car on the dyno and couldn't figure out why the the hp and tq didn't cross at 5252?


I found this confusing as well, but it really isn´t
Smiler
That sheet has two scales, Hk (or hp) on the left from 0 to 700, and Nm on the right side from 0 to 1210. If you instead would have a single scale showing Hk and Nm from, e g, 0 to 1210, the lines would cross at 7024 rpm. Why 7024?
Because 1 ft lbs = 1.34 Nm and 7024/5252 = 1.34

So, in this case with Nm, the lines would never cross, because the engine doesn´t rev that high.

Makes sense?
I didn't even notice it till I saw 618hp. I have look at a lot of dyno charts but I can't remember ever seeing a streetable 408 get even close to that number. Don't take it the wrong way, your car sounds great but that would be a 700+hp 408 @5800rpm. I am guessing the person running the dyno turned in some correction or something.
quote:
Originally posted by 8pack:
I didn't even notice it till I saw 618hp. I have look at a lot of dyno charts but I can't remember ever seeing a streetable 408 get even close to that number. Don't take it the wrong way, your car sounds great but that would be a 700+hp 408 @5800rpm. I am guessing the person running the dyno turned in some correction or something.


The 618HP @5800 is not rearwheel horse power, but is calculated at the crank. The Dyno makes alot of calculations on 3-4 testruns, where it measures the loss in transmission etc.
The Guys who runs the Dyno, says it's correct within 2-3%

I saw a similar engine, with the exact same parts, build by Hot Rod Magazine, make 621 HP in a Dyno.

Mike Drew build an engine exact like mine, but with another cam. It made 564 HP @5800

But You're right.... 618 HP is alot in a 408 Stroker. Don't know if it's correct, but it pulls HARD, and that's good enough for me Big Grin
quote:
Originally posted by danishcarnut:


The 618HP @5800 is not rearwheel horse power, but is calculated at the crank.


Now I'm up to speed Yeah Baby! I am getting ready to dyno my Pantera in a couple weeks that's why I have been looking around to see what other people are putting down. I have a little more motor than most but I don't think it will put down over 600hp to the wheels.
I have a professionally built 408 with a dyno sheet (on crank) of 593 HP. So I was a bit sceptical about a "homebuild" and not adjusted engine of same size having considerably more power. But then somebody sold an engine just like mine from MME with 680 HP. So now I'm puzzled. Where did that extra 87 HP come from?! 593 is already a lot from 408 naturally aspirated cubes...

Is this like selling elastic band by the yard?
I don't get Your point here Mikael.
So You're saying that because my engine is partically put together in my garage will have less power than a similar engine put together in a professional shop ?
My engine components where handpicked by Dan Jones and others, and all the machine work done professionell by local experts, who also build dragracing engines.

The people at the Dyno is also very professionels with years of experience and a good reputation. So I have no reason to doubt their result.
We adjusted the engine at the Dyno, but will re-adjust this spring after I have installed an AFR gauge so we can follow the numbers more precise.
Heine, re-read my posting maybe? My point is that people who make a living on this quotes HP numbers to us that perhaps/perhaps not are a bit optimistic?

I don't know if your engine has more power than mine, I'll be willing to test that on the street any time. But if I compare our 408s I'd doubt yours would be considerably more powerful. We all know Dan Jones' skills, he's also helped me so that's not in question. But if I compare the world's claimed leading Cleveland builder, winner of Jeg's engine Masters more than once, doing a complete engine dyno and adjusting carb and ignition, if I compare that to Danish engine builders, dragracers or not, I know where I'd put my money. And remember your engine has not been dynoed, your car has, and then the nice guy at the dyno adjusts a lot of things. I'd be careful on numbers like that. It may be what the American's call a Happy Dyno. All customers leave happy.
But that's just me.

I'm sure we get an opportunity to settle this the right way some day, on the street Cool
quote:
But if I compare our 408s I'd doubt yours would be considerably more powerful.


Mikael, maybe your pro engine builder made a mistake in your engine since it develops so Little HP compared to the other 408 builds here on the threads Big Grin

Maybe he forgot to portmatch the intake gaskets ??

Kidding aside, I don't think you can compare your engine to Heines, he has different heads, more compression, different cam etc., etc. .... and what's the point?

Kristian, you know the guy with the BIGGER ... engine
Last edited by push1267
@Mikael

Yes, everything have been matched. Not that it really needed it, because intake and heads are TFS. Trimming was minimal. They almost matched perfectly directly from the box.

The AFR Meter will tell me if it run rich or lean, and in what rpm range I may have a problem. And with that knowlegde I can finetune with other jets. Like You say: Every Little thing counts..... An engine running rich will cause a loss in power, so ofcause it will help to lean it out, if that's the case.

Not trying to start a pissing contest or whatever", 'cause I really don't care. Razzer Maybe the Dyno is a Little on the "Happy Side"....??? I don't know, but like I said before, I doubt it. All I know is that the car has enough power and torque to make my heart skip a beat, and scare the sh** outta me. And that's good enough for me

@Kristian: Haha, BIGGER engine........ Not for long. My Engine-Guy and I talked about making a HUGE Cummings Diesel for the Pantera. That will be fun Jester
Last edited by danishcarnut

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