OMG! 210 ft/lbs of torque @ 1200 rpm!

Post by **autoworkz** » Mon Aug 28, 2006 10:38 am

can i say it again, i love this motor. we got her back together from the crank issue and apparently jumped a tooth on timing while going back together. what do you want, we didn`t even take the valve covers off to do it. anyways, so we got the timing right and advancing it 5* brought us up to 238 hp i think and the torque curve isn`t a curve at all, it just starts. we even tried start to record the run as low as 900 rpm and it`s still up there, almost a straight line from start to finish. stinky has resocketed the ecu and will probably start the tuning tomorrow. i`ll get dyno graphs up soon.

Post by **elwesso** » Mon Aug 28, 2006 10:46 am

nice..... I remember reading that 90% of the torque is available at 2000 RPM, according to a VH45 engineer.....

Seems about right, too bad on the Q45s grandma gears prevented us from experiencing that.

Post by **Stinky** » Mon Aug 28, 2006 11:47 am

Here are the graphs. After looking at the timing maps I think a great deal of the dips are due to timing. Anyone have a guess as to why they would have the timing set like this? Either way I'll be making some changes soon.

Post by **sijoko** » Mon Aug 28, 2006 11:53 am

autoworkz wrote:...the torque curve isn`t a curve at all, it just starts. we even tried start to record the run as low as 900 rpm and it`s still up there, almost a straight line from start to finish. stinky has resocketed the ecu and will probably start the tuning tomorrow. i`ll get dyno graphs up soon.

The VH45 was designed to provide 90% of its torque from 2000 rpm.

I sent away for the SAE paper on the VH45DE and there is a Power Output chart. It shows that at 800 rpm there is almost 240 ft-lbs. of torque available.

The chart shows that the torque curve is pretty linear. It starts at 240 @ 800 rpm, peaks at 292 @ 4000 rpm and finally dips to 225 @ 6400 rpm where the chart ends.

Of course, if the engine was tested with the VTC disconnected, as many have stated, then the numbers would be even higher.

Post by **Stinky** » Mon Aug 28, 2006 4:08 pm

Actually we did some runs with the vtc turned off and with the vtc on. Based on those runs the vtc rpm set point is set pretty well. We didnt notice any point at which changing the vtc setting would make any gain in power.

Post by **sijoko** » Mon Aug 28, 2006 5:16 pm

Stinky wrote:Actually we did some runs with the vtc turned off and with the vtc on. Based on those runs the vtc rpm set point is set pretty well. We didnt notice any point at which changing the vtc setting would make any gain in power.

What was the difference in power with the VTC on and off? I figure the extra overlap should have made a noticeable gain.

Post by **Stinky** » Wed Aug 30, 2006 8:46 am

We had a chance to do some tuning today. First let me explain that the previous graph in this post was created with the cas advanced 5 degrees past stock and it was also using a different ramp rate. Please dont try to compare the previous graph to the new graphs. On to the good stuff. The next 4 runs were taken using Dyno Dynamics shootout mode with 8 cylinder settings. The cas was set to stock. Runs 131 and 132 were using the stock 90_60U00.bin file and represent a stock tune. Runs 129 and 130 were using a tuned version of the same stock bin file. No other changes were made between runs. You will notice theres quite a bit of improvement between 3700rpm and 5900rpm. The stock bin put out a max of 236.9 hp while the tuned bin put out 249.3 hp. This is just from tuning the high rpm/load timing.

Post by **Mettler** » Wed Aug 30, 2006 11:22 am

Ignition timing ?

Post by **Stinky** » Wed Aug 30, 2006 11:30 am

Yes, ignition timing.

Post by **Mettler** » Wed Aug 30, 2006 12:25 pm

Impressive, would love to see what results you start getting as you play with the fuel maps.

Post by **autoworkz** » Wed Aug 30, 2006 5:18 pm

we set the afr REAL rich on the high end, around 10s i think. no power made, but we`re not done...

Post by **Mettler** » Wed Aug 30, 2006 6:11 pm

Huh, the factory maps are around 10:1 IIRC, I was looking at the map at my mate's house a month or two ago. I reckon there's a lot of power (and fuel efficiency) to be unlocked through tuning the AFR correctly.

Post by **Q45tech** » Fri Sep 01, 2006 6:23 am

Back in 1994 I purchased a prototype reprogrammed ecu [that Dinan Engineering had tweeked on a 1990 Q45]...............the 16 year old fax dyno copies are very washed out but they and the numeric data show the same curves and improvements.

As I remember the telephone conversation they tried over 40 dyno runs and ecu tweeks but they did get to a flywheel 318+/337 lb/ft

My peak advance runs 28>29 degrees at 6600-7300 rpm vs your 25 at cutoff?

Since these engines live so long, an interesting study would be the the effects on the chain stretch [exhast and intake cams get retarded vs crank]..I have had to reset the CAS twice [about every 100,000 miles] to correct for chain stretch.............seems to change ~~2-2.5-3 degrees per 100k.

Post by **Stinky** » Sat Sep 02, 2006 2:46 am

That's interesting about the chain stretch. It would be nice to know how the change in cam timing effects hp.

Do you know if 15 btdc was the standard idle timing on all 90-94 models?

I really didnt pay too much attention to the high rpm end of things yet. I'll have to see how raising the timing to your 28-29 helps. It certainly would be nice to get rid of the hard dip towards the end of the curve.

Post by **Q45tech** » Sun Sep 03, 2006 9:10 am

15BTDC was standard across the board. The runner length from valve midlift to plenum is too long to not roll off at redline appears to be tuned to 6,000 rpm

OMG! 210 ft/lbs of torque @ 1200 rpm!

OMG! 210 ft/lbs of torque @ 1200 rpm!

Re: OMG! 210 ft/lbs of torque @ 1200 rpm! (autoworkz)

Re: OMG! 210 ft/lbs of torque @ 1200 rpm! (autoworkz)

Re: OMG! 210 ft/lbs of torque @ 1200 rpm! (autoworkz)

Re: OMG! 210 ft/lbs of torque @ 1200 rpm! (sijoko)

Re: OMG! 210 ft/lbs of torque @ 1200 rpm! (Stinky)

Re: OMG! 210 ft/lbs of torque @ 1200 rpm! (sijoko)

Re: (Mettler)

Re: (Mettler)

Re: (Mettler)

Re: (Q45tech)

Re: (Stinky)

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