Another day on the dyno

[Zuffen]

Had a dyno day today.

HAd an interesting and day with a few dissapointments.

Best run was 258RWKW which with a 91/2" diff and transfer case probaly equates to around 475FWHP.

I'm still not convinced we have enough timing dialled in but we picked up 40RWKW with an additional 2 dgerees of timing!

After the last run it developed a miss which we've tracked down to an LS1 coil failing.

I left the car at the tuner's and will return on Monday to do some sorting out.

At one stage we lost the TPS signal and all I can think of is a wiring fault in the loom that was professionally made for the job. I'll get onto it first thing Monday and we may get some better figures.

The supercharger whine is so loud we wouldn't be able to hear any det so we're playing safe.

I'd be perfectly happy with another 40 or 50RWKW. 300RWKW is a nice round figure.

We did one short run on the road and it certainly gets up and boogies.

 

[XR8tt]

I assume with the weight & size of transmission, tyres the actual power would [as you say] be alot higher...??
I bet it sounds good...

 

[cribbj]

Rod, congrats on the results. What was your boost and timing at those outputs?

I think those of us with SC's just have to be satisfied with lower peak power than the turbo boys, because we lose a lot in the SC. Some calcs show that with belt loss, at high boost, we could be losing as much as 80 HP, even with our twinscrews. I find that figure a bit hard to swallow, but I'd believe 60 or so. What we have, which the turbo guys don't, is the instant torque on demand, down low.

 

[Zuffen]

John,

Not sure on the timing as we didn't print any runs but I'll chase it. From memory max anywhere was 23degrees.

I was going to ask the question, how much timing are people running, as it is certainly where the power is.

The torque is there from idle and then it really moves as it revs.

Bosst is 21.5psi and we can get that at less the 1,500rpm!

From what I've read it is 80+hp in drive losses. Corky Bell has a calculation for it but I'm too lazy to do it.

Graeme,

I agree my driveline losses may well be higher.

I may stick with what I have but you never know there's always another pull to be taken.

We've now done well over 50 full power pulls on the engine and it still seems happy.

 

[gloverman]

Well done Rod. Good to hear its nearly at the end of the job so you can get out and enjoy driving it. Cheers

 

[Zuffen]

Well, wasted another day at the workshop.

After another twenty or so pulls trying to sort out the ignition miss but we're no closer.

At this stage we've swapped coils and wires and now feel the Iridium plugs may be the problem. I pinched a set of coils out of a car used for burn out comps that's fitted with an LS1 that we blew up on the dyno Saturday night. The owner didn't seem all that thrilled!

We're using PFR7G11S plugs (in fact two sets that we change fairly regularly and on my engine that is a bugger) as these seem the only plugs we can find that fit. To me that doesn't make sense.

I'm going to try some copper plugs (if I can find an equivalent) to see if that clears up the miss.

I may go another heat range cooler as that may allow us to dial in another degree or two of timing.

So far I've used 80litres of fuel since saturday morning!

We're using 98ron pump fuel so no cheating here.

A couple of observations. The output air from the supercharger is hot enough to heat the intercooler pipe to the point it gives you a nice burn if you let your arm contact it even momentarilly. Ask me, I now have a new scar. The intercooler pulls the temp down to 60degreesC regardless of the outside temp. I'm really impressed.

The EA Falcon cooling fans do a better job than the dyno's 3' ducted fan at cooling the engine. We can do a pull with the Falcon fans running without the dyno fan but not the other way around. I would recommend the Falcon fans to anyone trying to cool an engine.

I'm back there tomorrow to see what we can do.

The engine still seems happy so let's go give it another hiding!

 

[XR8tt]

What gap are your plugs ??
I find normal plugs to work better on forced engines..
Try .025 gap then increase ???
You could be blowing the spark out ...

 

[Zuffen]

Graeme,

We're down to .8mm, 25thou is just over .6mm.

I think copper plugs may be the answer.

 

[XR8tt]

May have to fit a CDI ignition ??? Maybe the longer duration spark will help ??

 

[Zuffen]

We finally sorted the miss out.

After running compression and leak down tests (both excellent) we were stumped.

We tested all leads (we'de already confirmed the coils were good) and found one of the new leads with over 10K or resistance.

I called home and collected an old plug wire and grafted an LS1 end onto it and away the beast went.

The last dyno run gave us around 235RWKW and I'm leaving it at that. The torque spread is over 3,000rpm so it will be very a drivable engine. In a car the weighs over 4,000lb torque is more important than brute HP.

The engine has sustained over 80 full throttle pulls and is still in great shape. Makes me feel fantastic as I assembled the engine!

We could have gone for more power but figured this is around 400/425FWHP so enough is enough. We only revved it to 5,750 so there was another 750rpm before the cams started to drop power.

This all makes me think John Cribb's 500 on an engine dyno Justen with outrageous power is the real horsepower hero out there.

I also feel asking more than 500FWHP from a supercharged street 1UZ is probably a bit too much. We could have reverted to our earlier tune that gave another 75odd more FWHP but we felt it was becoming a little marginal with detonation.

I don't want to re-build this engine again so accepting a little less may be a sound economic decision.

Interestingly my first dyno run on this engine was 85RWKW. So we've come a ways. Just shows how bad the first tuner was.

Now to get out and drive it like I stole it and see how it performs off-road.

 

[XR8tt]

Great to hear Rob...
Yes it's pulling some weight & has grip...
Leave it at a durable power level..
Besides those numbers are at WOT...
The little 1UZ will still power along just nice cruising...
Building / assembling the engine etc... Gives a different meaning to pride ha ??
Good on ya !!!!

 

[cribbj]

Glad to hear you're finally running well, Rod.

Coming from the Supra world, where 1000 and 1200 HP is pretty common out of a 3.0l motor, I figured it would be a doddle getting 500 out of these 4.0l UZ's, but we just haven't found the key to making big power with them.

 

[JustenGT8]

hey John,
Good to hear it's impressive on the road, as that is what really counts!!

Are you running the WI? 60 deg sounds a bit high....i thought these twin screws were efficient? With 50:50 water/meth (with no IC) i have got my inlet temps down to 50 deg C running 16psi thru the M122 roots. You are running a fair bit more boost but i would have thought the twinscrew would have done better?

For my setup it looks like the stock 10:1 compression ratio is an important factor in the power it makes. We made a lazy 270rwkw on a soft tune to keep the old girl alive and apears to be working so far. Apart from the strong internals the main different between our engines is the comp ratio i think? You don't have cams or headwork eh?

John, the key to power with these things is a decent set of heads. We have n/a VVTi 1UZ making 200rwkw here stock with just tune and headers. So either a very clued up port job on the non VVTi heads is needed or just use the VVTi set (with no VVTI actuation). I guess we'll have a better idea once my new TT engine is finished....just need to be patient as that may be a while

 

[XR8tt]

Easy people...
The way most dyno's measure power I would say there's close to 150+ h.p lost in big heavy transmission etc... Takes along time to spin up like a big ferris wheel. The dyno calculates this time into its power etc..
Throttle response I guess from 1500 - 4500 rpm would be interesting, more important on 4WD...

It would be expensive.. An engine dyno would be interesting!!!
I have seen gains with swapping to lighter wheel combo, alloy drive shaft...A 4WD is all about strength, traction...

Getting the power to the ground on high output engines on heavy vehicle puts far more stress on the engine than a light vehicle with much smaller tyres also...

 

[Cobber]

Well done Rod, what a journey.

What's next on the project lit.........

 

[Cobra]

Rod

Have you calculated the cost per kw yet?

 

[XR8tt]

Well done Rod, what a journey.

What's next on the project lit.........

Conversion on the Merc ?? Ahahah

 

[Zuffen]

Ok,

Justen,

Yes we're running heavilly ported heads.

I figure another 0.5mm on the porting and we'd strike water!

Kelford 207 (I think, it was years ago I purchased them) cams complete the package.

Graeme,

You're right the rear driveshaft would weigh 15-17 kg. The rear diff centre weighs 47kg and is 91/2" pinion so everything is big and heavy. Wheels are around 45kg each.


Cobber,

Sell this and find something that uses an engine that won't get me divorced for the amount I've spent on it. There's a twin supercharged Ferrari based hot rod on the horizon. JC knows of it and it could be some fun. Now this is driveable that's next! But I'm not paying the bills.

Brett,

Around $275.00 per horsepower. My God I could have purchased and fed all those horses for that!

Graeme,

The SLK may see a new chip, particularly if I can roll a faster 0-100 time than my wife's car!

I plan on timing some 0-100 runs and see what I can get then decide if going to the drags will be rewarding or embarrasing? Not sure if a first gear start will be faster than a 2nd gear start as these 4x4 boxes are pretty low in first

Lastly here's a print out of the dyno sheet,

Note the first pull we did netted 85.8RWKW. Geee was I excited. Nearly topped myself there and then.

I picked up around 80RWKW for 4 days work (I haven't seen the bill yet) and the car is much more drivable.

 

[cribbj]

There's a twin supercharged Ferrari based hot rod on the horizon. JC knows of it and it could be some fun. Now this is driveable that's next! But I'm not paying the bills.

Just a clarification; that twin supercharged Ferrari project isn't mine I might be nuts enough to try something like that, but my pockets are nowhere near deep enough to fund it!

 

[Zuffen]

On the intake temps I noticed once the engine was switched off the heat soak in the manifold would take the temp to 80degrees in a matter of a minute or two.

Once started it would drop back to its usual 60degrees within two minutes.

I run 6mm phenolic spacers on the manifold plus the bottom of the manifold is covered with a sheet of 6mm phenolic material that closely follows the shape of the manifold.

I'm seeing a 60+degree temp drop through the intercooler.

But 60degrees seems the temp it always runs at.

The IAT sensor is placed in the bottom of the manifold close to the geographical centre of the manifold.

The mixtures at the plugs is damn near perfect. Taking the air out of the charger and through the cooler allows for a more rational air flow within the manifold giving even air distribution and eliminating rich and lean cylinders.

I've always wanted a blown engine, now I have one.

If I did it again I would use a stock engine and go the turbo route and have the whole thing done for a 1/4 of the money, and most likely have more power but in a different place.

The low down grunt is impressive, whilst it just winds up as it revs. Not too sure I could have that with a turbo setup.