Builds 2F + (3F-E) = 2FETI Into My FJ40 (1 Viewer)

[matt.mcinnes]

The wastegate valve-seat was never installed at MPC I have a photo of it in the box though. Hmmmmm

Anyway that aside the wastegate is in and working.

Couple of hour on the Dyno adjusting for it.



Now I need to update my signature

Same boost I was tempted to tweak it up a little but no need now.

8PSI 170kw228hp and 745nm/550ftlb @ RW

 

[RockDoc]

Dude something is wrong with those numbers.... 550 ft-lbs at 3625 = 380 HP at 3625. Something is wrong the numbers they are giving you (it's not your conversions, they are good).

FWIW, in imperial the relationship is Torque (ft-lbs) x RPM (of the torque reading)/5252 = HP (at that RPM)
Torque in ft-lbs = HP at 5252 RPM

Conversely, HP x 5252/RPM = Torque

 

[matt.mcinnes]

Dude something is wrong with those numbers.... 550 ft-lbs at 3625 = 380 HP at 3625. Something is wrong the numbers they are giving you (it's not your conversions, they are good).

FWIW, in imperial the relationship is Torque (ft-lbs) x RPM (of the torque reading)/5252 = HP (at that RPM)
Torque in ft-lbs = HP at 5252 RPM

Conversely, HP x 5252/RPM = Torque

That maybe at the engine?

Gearbox,diffs and tyres will effect rwhp and rwftlb will it not?

 

[RockDoc]

That maybe at the engine?

Gearbox,diffs and tyres will effect rwhp and rwftlb will it not?

It will lower them both, but the relationship will still hold at the rear wheels. I suppose they have to correct the torque value for gearing, but I sure thought they would do that. It's engine torque you are after, not 1st gear driveline torque or something stupid like that.

What gear are they running it in when they do the dyno run? High range or low? That could be the issue right there, if they are dynoing it in low, but not taking into account the 2.3 : 1 or whatever transfer gearing you have.

 

[zuluzeugma]

It will lower them both, but the relationship will still hold at the rear wheels. I suppose they have to correct the torque value for gearing, but I sure thought they would do that. It's engine torque you are after, not 1st gear driveline torque or something stupid like that.

What gear are they running it in when they do the dyno run? High range or low? That could be the issue right there, if they are dynoing it in low, but not taking into account the 2.3 : 1 or whatever transfer gearing you have.

Every DYNO i've ever heard of runs the tranny in 1:1

 

[matt.mcinnes]

Every DYNO i've ever heard of runs the tranny in 1:1

Dyno run is in 4th 1:1 in High

 

[RockDoc]

Power/Torque Conversion @ The Autistic Cuckoo

You need to talk to your dyno guy... you've put too much into this truck to end up with wrong numbers.

 

[matt.mcinnes]

Power/Torque Conversion @ The Autistic Cuckoo

You need to talk to your dyno guy... you've put too much into this truck to end up with wrong numbers.

You would have to Dyno it through the axles not the tiers and then take into account the diff ratios from what I under stand but I just drive it.

It halls ass.

 

[Dougal]

Dude something is wrong with those numbers.... 550 ft-lbs at 3625 = 380 HP at 3625. Something is wrong the numbers they are giving you (it's not your conversions, they are good).

FWIW, in imperial the relationship is Torque (ft-lbs) x RPM (of the torque reading)/5252 = HP (at that RPM)
Torque in ft-lbs = HP at 5252 RPM

Conversely, HP x 5252/RPM = Torque

I think you're right.

Working in metric (like the rest of the world does), 4500rpm is 471 radians/second.
178,000 watts divided by 471 radians/second is 377Nm.

The dyno guy has the power plot right, but he hasn't entered the diff ratios or tyre size correctly, as a result your torque figures are showing roughly double what the uncorrected flywheel torque would be.

If you have 30% driveline loss, then you've got around 540Nm. Quite good.

Another way to check it, petrols can only do around 100Nm/litre without boost, 8psi boost can give you 50% more air.
So the max you're ever going to hit with 8psi on a 4 litre engine is about 600Nm, I'd say you're not far off it.

 

[matt.mcinnes]

So the up shot is I have 170KW and 370Nm at the RW

With 30% drive line loss 540Nm at the fly appox and the Nm would then be at the fly?

 

[malcb]

So the up shot is I have 170KW and 370Nm at the RW

With 30% drive line loss 540Nm at the fly appox and the Nm would then be at the fly?

THink you meant KW at the flywheel, beats me because I am not sure about the revs, from my old post #681 in this epic thread.

 

[matt.mcinnes]

My truck is real fast and that's all I need to know

 

[Dougal]

So the up shot is I have 170KW and 370Nm at the RW

With 30% drive line loss 540Nm at the fly appox and the Nm would then be at the fly?

If the dyno guy didn't put a correction factor in, then yes you've got 170kW at the rear wheels.
Torque at the rear wheels is misleading so it's best to ignore that.

And if you're losing 30%, then you've got 242kW and 520Nm at 4500rpm at the flywheel.

Unless of course the dyno guy has already put some fudge factors in to confuse us.

 

[matt.mcinnes]

If the dyno guy didn't put a correction factor in, then yes you've got 170kW at the rear wheels.
Torque at the rear wheels is misleading so it's best to ignore that.

And if you're losing 30%, then you've got 242kW and 520Nm at 4500rpm at the flywheel.

Unless of course the dyno guy has already put some fudge factors in to confuse us.

KW will be right Nm is always subjective to correction.

But I'm happy with the results now the wastegate valve seat is in and it's unlikely I will wind the boost up now with the power already gained.

 

[Dougal]

KW will be right Nm is always subjective to correction.

But I'm happy with the results now the wastegate valve seat is in and it's unlikely I will wind the boost up now with the power already gained.

Some dynos use the coast-down speed to calculate the driveline loss and corrrect the power curve based on that. It might be worth asking the dyno guy as we could spend all our lives guessing if that's measured wheel kW or predicted flywheel kW.

One question I've always been curious of, how much power can that 40 chassis handle?
Do you have any issues with axle tramp? Does it go sideways with every stab on the throttle.?

 

[matt.mcinnes]

You can stand on it as hard as you like and it just goes straight. No pulling at all infact it's real smooth. Quite surprisingly so. Your not fighting it at all.

Really happy with the results for a shorty.

 

[marin]

Yeah, gota agree with that, it drives really nicely, puts down the power when you put your foot down ..... now just to make those speed bumps a little smoother lol

marin

 

[matt.mcinnes]

Yeah, gota agree with that, it drives really nicely, puts down the power when you put your foot down ..... now just to make those speed bumps a little smoother lol

marin

Except when the roads wet that's a diferent story

 

[matt.mcinnes]

This is a run on a different dyno we were testing the intercooler.

Pre and post MAP across the intercooler.


Pre and post temps across the intercooler.


Oh yes in the first graph Blue lines are Marin's Mav 4.2Turbo Diesel

 

[RockDoc]

420 ft-lbs and 244 HP... Nice, twice stock engine numbers.