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All 96 of'em - Roper's 8V on the Dyno

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The graph below is a little tough to read, but the closely paired lines that start low and snake high is the power curve, and shows 96.10 hp... this is with the GT-Rx R/S exhaust, and *NO* other mods (including fueling). The other sine wave pair, is that of the air/fuel, and it should be flat-lined around 13.2-ish (red dotted line) to make good power.. you can see it spikes to critically rich/lean levels at low and high rpm, no good. Pete will expand, but he mentioned in his e-mail to me, that the dyno shop could install a PCIII to help increase power on top, which could be done to the tune of a PCIIIusb and mapping *however* it will not correct the lower rpm range that all of us ride in. If you live only on top of the power range, this will get you by for now :huh: -- that is until the PCV is available, hopefully just into the new year.

I'm trying to get the digital run files to show torque as well... hopefully Pete can pry it out of them.
Thanks Pete for the legwork on this, and sending along the dyno chart, Cheers mate! B)
 
Greg Field wrote:
The a/f chart suggests it is critically rich low and high.
Click to expand...
Absolutely, and this is only at 100% throttle. I'd wager we'll easily see over 100 rwhp on the dyno once the fueling is sorted... now, questions is, where is it for the rest of the ride-able range. ;)

p.s. I generally ignore all the low rpm spikes, as the dyno operator has everything to do with those. Loaded/static mapping on the dyno will tell the real story though.
 
If uyou see what improvemants are made to the engine over the old 4v, I don't get it why it doesn't give more. My 1225, with cam between centauro and c kit, has 115 at the wheel on a dynoyet 150.

From my testdrive I remember the power curve of the new 4v even more top oriented than my own engine. It feels like the map isn't right below 4500. My bike has an immidiate reaction on the trottle, on every rpm. The stevio not.
I don't know if a pc will get everything out of the engine, what is needed is a real new map in the 5am. OR put carbs on it:)
 
Anywhere around idle is almost always rich. Just off idle isn't really super-critical in my book as even if you *can* get it to pull from there I always worry about oil pressure and supply to the bearings simply because the pump will be spinning so slow.

These were basically full throttle runs. Stick it in top, run it to about 2,500 and nail it. It bucked and jumped a bit right down the bottom and the whole really important area between about 3K and 4.5K is poxily lean which is bound to be related to emissions. Then up the top it is stupid-rich. Brett reckons most stock maps in almost all bikes are, it's supposed to be a 'Safety' feature, presumably to stop 'tards frightening themselves and getting in out of their depth. Couldn't possibly ask people to take personal responsibility for their own actions and abilities could we????:angry:

We did a couple of runs holding the RPM on the brake and that too showed some fairly awful fueling deficiencies. Essentially though there was little point in doing much as there was no way to actually change anything.

So, what's the next step? Well, Brett reckons wecan sort the top end/open loop fueling with a PCIII as fitted to one of the Ducs that use a W5AM. This it may well be able to do by modifying the injector pulse but that will be it. I'm sure it will allow us to get more top end but it won't probably solve any of the closed loop portion problems or bottom end running generally. OK you ask. Why do it? Well the simple answer is that someone has to. Supposition and guesswork are all well and good but unless someone actually goes out and collects the data and presents empiricle evidence that is all it will be, supposition and guesswork. I'm lucky in the fact that I can do this sort of stuff, even if it turns out to be a complete waste of money, and it won't mean I have to eat snails for a year and neither will I feel compelled to sing something's praises simply because I've spent a motza on it. To me it is *important* research that will allow me to offer people objective advice and suggestions rather than simply a load of old guff and flannel to separate them from their cash. I fully expect this to be, at the very best, only a partial success and a 'Band Aid' measure. I expect that the PCV will be a far better option and as soon as that is available I'll be experimenting with that.

I think that *ideally* what is required is the ability to extract, modify and re-load maps into the W5AM, the thing is that currently options for this are limited and expensive. I believe that Phil Arnold is more up to speed with this than I am and when he has a bit more time I'll pester him but he's currently at sea a lot of the time and I don't think he has the spare time to waste gas-bagging to me.

Anyway, the PCIII option will be being explored in the next couple of weeks I hope as Brett isn't shutting down during our summer break. He's already done some playing with the PCV but this is currently only available for Harleys. we have to wait in line behind the Duc boys, the Japs, Aprilia and probably uncle tom cobley which is a PITA but you have to accept makes financial sense for Dynatek.

Anyways, happy X-mass guys and gals and even with the base #2 map and only the GT-Rx pipe I don't think that 96 horses is too shabby, (The #1 map would of been even worse I'm sure in terms of C/L lean-ness which is why the 8V tends to hunt and surge at low throttle in the 3-4K range with that installed:S ) I'm sure that with a DECENT map modifier and more free breathing induction figures close to Paul's Daytona with much better bottom end are going to be readily achievable.

Pete
 
Do you also have maps of the bone stock bike, before any mods? I wondered if the air/fuel ratio was at least more consistent in the factory setup(Of course in made less power!)
Also, I guess the Stelvio has different cams, etc, but does any of this translate over to that model?
 
I also noticed that the run was done at WOT. Is it possible/probable that A/F ratios are better at more real-world throttle settings at the various RPMS? (I've got a new Stelvio--you're making me squirm a bit:S :blink:)
 
The reason why we only did a couple of WFO runs was, as stated earlier, there was no way to change anything so these were just a preliminary run in the interest of finding out 'What it would do' and what the baseline fueling was at full noise.

Yes the A/F ratios will be different at other throttle openings but I'll bet you London to a Brick that in the areas where one 'Cruises' they will be as lean as buggery.

In answer to the first question No I haven't got info on the bog-stock bike. The #1 map is even leaner in the critical 'Cruising' areas which is why, on the Griso at least, there have been reports of surging and hunting on a constant throttle, As for WFO? A motor is simply a self propelling air pump. Restrict the inlet or exhaust sides and you'll richen up the AFR. That being the case if it is super-rich at the top with the GT-Rx R/S pipe on it would be positively drowning with the stock colostomy bag on!.

Why is this making you squirm John? All we're trying to do is get it to work the best it can as its designer originally intended before the pen-pushers and shiny-bums got involved in screwing things up!

Pete
 
John in PA wrote:
I also noticed that the run was done at WOT. Is it possible/probable that A/F ratios are better at more real-world throttle settings at the various RPMS? (I've got a new Stelvio--you're making me squirm a bit:S :blink:)
Click to expand...
Per what Pete says above, stock would be worse in the rich areas, and why the stock-mapped 8V ECU is finicky to intake/exhaust modifications at steady/cruise rpm. I haven't had any experience yet with map #2. Hopefully I'll get to expose the data here in the States within the next few months at Dynojet in Vegas.

In the mean time, if there is anyone out there with a stock 8V (including mapping), I'd pay half of a dyno pull (should be no more then $40 max) if the dyno operator can give me the digital run files. Any takers?
 
One of the things I was told by Mario who has had one of the failed 8V's completely to bits was that the crankcase and cylinder spigots were obviously designed to accomodate a larger bore so one can assume that in the not too far distant future the much anticipated 1400 will make its debut.

Pete
 
Much anticipated? Because that would be so much more appropriate for Euro-4 when that arrives in 2010? :-/
 
Pete,
I always enjoy reading your wit. I`m impressed with the hp especially considering such a rich running motor. That nose dive into hydrocarbon hell at peak rpm has me scratchin my head and other areas... I`ve read about and personally experienced overly rich mixtures with some two into one systems due to over scavenging , but usually a pretty long duration cam is part of the problem. What kind of valve timing do these new motors run? Is the head still considered a true Hemi? I had some long chats with Mr. Gold at ERC racing fuels, he explained that many tuners builders and the like erroneously go after some benchmark, say 12.5 12.7 or 13.2 AFR without ever giving the motor a chance to say what it likes best for peak hp/efficiency ( Dyno experimentation) Two similar motors may show not so subtle results when jacking with the AFR`s in other words. Been experimenting since and found the old two valve lemans really likes it on the lean side.. 13.9 -14.1 I`m really interested to see how your tuning comes along Good luck , beautiful GREEN Griso by the way, a man after my own heart ;)

Bill
 
pauldaytona wrote:
don'tknow if we had it here before, but here are some 8v tuning examples:
http://www.hmb-guzzi.de/html/tuninggriso8v.html
Click to expand...
It has been, but thanks again for the link/translated as well.
The Rapidbike unit shown in the link is only good for top-end, open-loop map corrections... and support in the U.S. is nearly nil. Good to see some top end numbers. Just imagine what one will be like with a blower/kompressor. :huh: :woohoo:
 
5154Guzzi wrote:
I had some long chats with Mr. Gold at ERC racing fuels, he explained that many tuners builders and the like erroneously go after some benchmark, say 12.5 12.7 or 13.2 AFR without ever giving the motor a chance to say what it likes best for peak hp/efficiency ( Dyno experimentation) Two similar motors may show not so subtle results when jacking with the AFR`s in other words. Been experimenting since and found the old two valve lemans really likes it on the lean side.. 13.9 -14.1
Click to expand...
BD, not to steer it too far off topic under this heading, but did you monitor engine/head temps when you went to 13.9~14.1? In all of my (several hundred+) dyno runs, I learned that the newer injected Guzzi motors like low 13's... where power and temp (fuel cooling on pump gas) met a happy mix (no pun intended). I would guess on your LSR bike, a few minutes at WOT wouldn't hurt it too much regardless, eh?
 
Hi Todd, Yes on the AFR gauge and monitoring. Aircraft Spruce sells a nifty gauge that measures both sides. Got her up to 320 f after a 4 mile blast down the salt at WOT. Thats starting at 230 and without benefit of much cooling air. The meteor really responded to the lean afr after many dyno runs at richer afrs. wasted alot of time down there. Of course it`s apples to oranges in comparing it with modern injected bikes, CR, cam timing, ignition and race gas make for a huge difference in tuning. A few questions, just how lean are you seeing stock guzzis as they come delivered? Does the new 8v Griso use larger throttle bodies than the 45`s that came on sports etc ? Is the 13.2 afr jetting used to eliminate detonation or bring it under control? Thanks dyno dude ;)

ciao` bd
 
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