Cans - Crossover

[Guest robbrugg]

Getting ready to buy cans, looking at these:

 

- Staintunes

- M4

- Mistral

 

But I'm wondering if I should do the crossover first, at the same time, or after.

 

Any ideas, guys?

[Guest Jay Mack]

There is a place in Ohio, EPCO Stainless, that makes wonderful cans and crossover pipes for Guzzi or whatever. I have a set on my Victory. They are made custom and you can specify a number of different alternatives such as length, glass-pac or mechanical baffling, variable noise reduction, cross-cut or otherwise. He'll make the Guzzi H-pipe crossover. Very high quality, individualized product for no more money than mass produced alternatives.

 

Try a search on EPCO Motorcycle Exhausts.

 

[helicopterjim R.I.P.]

If you plan on getting a Power Commander III to set the fuel mapping to match your exhaust modifications then I suggest you get both the exhaust cans and the crossover at the same time unless you don't mind tuning the bike twice.

I have Mistral cans and crossover and I enjoy them both but the Mistral crossover is biased towards mid range torque at the expense of top end horsepower. The midrange power makes the bike very easy to ride but I do notice that the power flattens significantly above 6500 rpm. I am going to try a Stucchi crossover as I have seen information that says it is more favourable for top end power and then decide wich one I wish to keep.

I am sure someone else can tell you more about the other systems available.

 

Good luck and enjoy.

[Guest IanJ]

I can only relate my experience, but here's what I got.

 

I tried out two different crossovers, with an otherwise stock engine: the Stucci and the Mistral. Neither one was as nice (with the stock exhaust cans, remember) as the stock crossover. Given the three different crossovers I tried, I would definitely stick with stock (and I did).

 

My recommendation is to get the cans first. My understanding is that they can produce an improvement by themselves, and that adding a crossover later makes that improvement more noticeable. My personal experience suggests that doing the crossover first just robs the bike of power and rideability -- that one I'm sure of.

 

If you're doing this in order to get more power in combination with a PCIII, I definitely recommend getting it all at the same time (including any induction mods you want to make) so you only have to muck with the map once. If it means saving your money for now, then do so -- it'll save you money in the long run, as well as headaches and wasted time.

[Guest Jay Mack]

Ian, I'm surprised to hear you opine that the stock crossover is better than the aftermarket crossovers, without changing the pipes first. I just got off the phone with Mike, who says the aftermarket crossover modification alone resulted in improved sound and horsepower gains.

By the term 'stock crossover' you're referring to the collector, the colostomy bag, aren't you? Or, are you referring to ta Guizzi crossover replacement for the collector?

I'm not disagreeing with you. I have no personal experience, but if you could flesh out your observations a little more, I'd be edified.

 

[robbiekb]

Ian, if you hadn't had the bike remapped before changing the crossovers it would run like crap

 

i'm putting out about 90rwhp right now with my stucchi crossover, mistral ti's, K&N pods and the high compression pistons and would never go back

[Janusz]

My first and only modification at the time was just the Stucchi x-over. My experience was totally different then Ian's though. Just a x-over with stock pipes got rid completely of the imfamous 4,000 RPM dip, added snap to the midrange and improved the sound.

 

The next was open Ferraci box. Much more intake sound and VERY lean running engine. Luckily,having Powercomander,five minutes with the laptop cured that.

 

Next, Ferraci pipes made a huge difference in sound. I canibalized GuzziTech.com out of identical set up map and after some seat of the pants improvements the bike runs as close to perfect as I can imagine.

 

I am a strong believer of introducing one mod at a time. After all, how would you tell what does what otherwise?

 

Also, indyvidual dyno mapping and trusting it totally is very risky IMO. You have to show a HUGE trust in abilities and integrity of an operator otherwise you might end up with hit and miss type of a map. The dyno machine, similarly to wheel balancing machine or alignment machine, is only as good as its calibration and operator's abilities. Some of these before and after graphs border on comical.

 

My map needed at least ten or more manual adjustments to make it 100% acceptable.

[bento]

but, i want to be rid of my cross-over. bubs perhaps?

[Mike Stewart]

Getting ready to buy cans, looking at these:

 

- Staintunes

- M4

- Mistral

 

But I'm wondering if I should do the crossover first, at the same time, or after.

 

Any ideas, guys?

No matter with which cans you go with, I would go with the PCIII first along with the cans. The crossover can be added at a later time unless you can afford to purchase all three at the same time. And yes, you will have to remap for each change.

 

Anytime you change something in the intake or exhaust and even the engine, you will have to remap the fuel mixture for your bike.

 

It make perfect sense to me that some do not feel very much gain with the Stucchi crossover with the stock exhaust. One reason for this is that the stock exhaust produces more back pressure in the exhaust system. The Stucchi crossover works by creating a perfect X (crossover) in the exhaust system. As exhaust gases from one cylinder pass the X part of the crossover, a suction is placed on the opposing cylinder. This scavenging effect is why it produces more power. A more restrictive exhaust and there will be less scavenging effect.

 

Mike

[Guest IanJ]

Ray, when I say stock crossover, I mean the box that's originally installed on the bike, downstream of the exhaust headers, and upstream of the exhaust cans, right in front of the rear tire. Replacing that bit with the Stucchi and Mistral crossovers is what I'm talking about as well.

 

Keep in mind, my bike is DEAD STOCK in the engine department. I have the stock exhaust, the stock intake, and NO PCIII. Anyone who replaces the crossover AND has a PCIII is talking about an entirely different beast, and I can definitely see how that would improve performance. With the bone stock ignition computer, iti does not make life better, but makes it worse.

 

So, just as I said, performance got worse with either of the non-stock crossovers. I didn't notice any difference in sound, but I wasn't paying much attention to that. I was looking for differences in power, and perhaps in fuel efficiency. I didn't really have either of them long enough to notice any efficiency differences.

 

I Ithink the Stucchi was worse, resulting in rough running throughout the range. I described it at one point as being like someone had hit the power curve with a hammer. Wham! Less performance for you!

 

The Mistral was much better, and I fooled myself into thinking it was better than stock while I had it. Then the stock crossover went back on, and it was like the bike had a new lease on life. Suddenly it had power in all these places it hadn't before. It was much freer revving. My seat-of-pants dyno recorded about a 7% increase in power all across the RPM range.

 

I'm probably going to have to break down and get a PCIII if I want to make any changes to the bike's engine. I have resisted for now, because I'm offended to think that MG would sell me an $11,000 motorcycle that requires a $300+ aftermarket add-on, just to run correctly. (I was having trouble with my mixture, and for all I know, I still am. Perhaps I've just gotten used to it.) I've been pondering getting K&N pods, and if I go to the trouble, I should just bite the bullet and put on new cans and possibly a new crossover at the same time, and get a PCIII and custom map. Obviously, that's around $2000 worth of mods right there, so I'm not feeling too motivated to do it.

 

I hope that fleshes out my description enough for you. Let me know if there are any specific descriptions you really want to hear.

[Mike Stewart]

I have resisted for now, because I'm offended to think that MG would sell me an $11,000 motorcycle that requires a $300+ aftermarket add-on, just to run correctly.

Ian,

 

It isn't that Guzzi could not get the stock map pefect on your $11,000 dollar bike.

 

It has to do more with the exhaust emissions that the bike has to pass in order to be sold in the States. Most bikes on the market are running on the lean side to say the least to get their bikes to pass these strict emissions. That is why the European map is different than the ones in the States, they run a tad richer over there.

 

If you look at the PCIII site, you will notice that they make one for just about everybike on the market. Why, so the consumer can adjust their machine to the perfect air fuel ratio.

 

Mike