Nitrovein

Well if it's in general perspective, ( ) gases don't change signal or amplitude by a change in length.

1QwkSport2.5r

I misspoke in how I worded that, maybe less of a speed/intensity thing and more of a time/distance thing? I get what you're saying anyhow.

1QwkSport2.5r

What turbo head buttons fit the Picco P3 .28? I know there are a few engine variations made by Picco but branded under another name that are the same parts. If like to convert my standard plug engine to a turbo plug... I just don't know what buttons fit besides the Picco branded one. Parts for these engines are almost non existent these days...

1QwkSport2.5r

FWIW for anyone reading this... A conical Novarossi 41016 medium length header and Dynamite 086HS pipe makes a Picco .28 an absolute BEAST. Power is absolutely ridiculous to the Nth degree when compared to the same pipe on the Losi LST header. Completely ludicrous.

supertib

Good to hear !!

I now have a LST manifold as well as the 41016 Nova manifold so I can do a back to back dyno test now.... can do them vs the traditional offroad manifolds too

1QwkSport2.5r

I'd be curious to see what the power difference is between the two. The manifold alone made a remarkable difference that I could see and hear, so I bet the difference substantial.

supertib

As the dyno shows the manifold in many ways is more critical then the pipe itself......

1QwkSport2.5r

That is NO B.S. The Picco ran warmer than I'd have liked, but it was tunable and no finicky with settings. It ran fine, just warm (240-260F). Changing to the shorter 41016 header was like a light switch. Power went way up, it was more responsive, and just in general sounded happier. Head temp dropped to 210-220F with a rich but clean needle setting. I struggled to get it to hit 240F running in the grass. It's still breaking in so I'm keeping it fairly rich. The timing on this engine is closer to the factory temp version. The pullstart version has lower timing than the factory team version. Now I just want to get my hands on a turbo head for it... Seems to be a hard part to find.

supertib

yeah the crank timing on those Picco 28's are all over the map....most of the OWB models have lower timing and the bump have higher timing but even then they still fluctuate a large amount...from measurements of 9.6mm all the way to 11.4 mm pinching a caliper across the intake opening of the crank and the bottom of the crank..... the smaller the number the bigger the timing window and higher the timing......I would have thought a button would be easy to find, but yeah I guess the new Boost 28 is a 2 piece unit now so you would also need a boost cooling head....

1QwkSport2.5r

I found a turbo head for the Schumacher .28 which was made by Picco I understand (thanks for that link Ant!). I haven't ordered it yet; I still have a pack of Picco standard plugs to use up. I'll probably get the turbo head and just hold onto it.

Is the heat range the same between standard and turbo Picco plugs? Or rather, what turbo plug would be comparable to the P6S Picco plug?

1QwkSport2.5r

Any developments in testing the on-road manifold versus the Losi LST manifold on an off road engine on the dyno? My Picco has been responding well to it.

supertib

I have been meaning to update this but have been pretty busy in the shop...

So yes, definitely made some progress and have done some testing.... sadly the LRP 30 I was using dropped the connecting rod during the testing with the 41016, but I did manage to test onroad vs offroad on a engine ( Picco EMX WCOnroad ) ... So exhaust timing plays a huge role and the higher the exhaust timing the shorter the manifold needs to be... So for a onroad engine if you install a offroad manifold the power drops thru the floor...... On the LRP 30 testing I had multiple engine issues that prevented me from getting a good read...but I can say that with the 9886/41016 the modified LRP 30 made more power then any other engine I have heard on the dyno......Issue was the engine seized 2 times from the crankshaft walking into the engine case and seizing up from the friction .... I ended up ruining a case and a set of bearings.... Something is flexxing, either the crankshaft or the engine case the crankshaft is rubbing out right behind the front bearing.. So I did the first pull and I could tell it was onto big power but it shut down... So I pulled it all apart, cleaned up all the rub marks, installed new bearings.... tried again... engine seized again......... So I rebuilt the engine again, used a fresh case, a fresh set of bearing and tried for a 3rd pull and the dam connecting rod let go.........done ! I never got a good read but I could tell for sure it was more power then I have had on the dyno before, it accelerated the mass like nothing I had heard before.... No without a reading its hard to say how the bottom end was, it could have lost some, but I do know the midrange and peak power were off the charts...... I may try it again with another LRP but I am wondering if I have simply found the mechanical limits of the engine and that against the weight of my dyno mass its not able to retain its rigidity well enough to get a proper run....So the next test may be with a less powerful modified offroad race 21..... I can say for sure that onroad engines do notlike offroad manifolds, and I am not sure yet how offroads are with onroad manifolds.... my testing shows potential for big peak power with a modified LRP 30 and a onroad manifold, so we will see... I will update this as I go along

1QwkSport2.5r

I suspect the LRP case is made from a less than ideal alloy - a common problem with Chinese and Taiwanese engines. I am LOVING my Picco .28 on the 41016/086HS Nova/Dynamite setup. With the way I set the Picco up, the top end is by far the craziest I've ever heard from a .28. It just revs and revs and revs. I am using the same fuel I've used for several years too - 20% nitro 10% oil (6% castor 4% Klotz synthetic). I am crazy impressed. I had tried the SH .28 6 port (all stock) on the 41016/086HS and it ran erratic, hot, and was almost impossible to get a good needle setting on it. I ran two tanks through it and gave up. It would need to be modified to run right on that pipe setup, so I yanked it out of the truck and put the Picco in. I could say with a reasonable level of certainty that a stock engine probably won't run well on a 41016 without making a lot of changes to the engine. The SH .28 ran like a scalded cat on the Losi manifold and Losi HT pipe, but hit the wall at about 27,000rpm. The pipe/manifold acted like a governor. The Picco runs like it has no governor - I have yet been able to find the actual top of what the Picco can do. It revs so high, I was scared of going too high, so I've not pushed it to the limit yet. One of these days I'll stick a GPS on the LST and see how fast it really goes.

I look forward to seeing your dyno results, Neal. Thanks for posting.

supertib

I have dyno graphs of a stock Picco 28 on a 9886/41032 ..I can dig them up and post them if you wanted the reference.......its a pretty stout engine for sure...

I have a modified Picco 28 here right now, I could easily do a 9886/41016 test this weekend ! then we could see how it compares to the 41032 ........

Novarossi when they get into the bigger power .21's they go over to a 14.5 mm crank instead of the 14mm like the standard engines run... a full blown modified Novarossi onroad .21 makes as much power as my fully modified LRP 30...but at higher RPM with less torque values... But if Nova steps up to a 14.5 crank for the big power it may be due to the same issues I seen the other day.....I have the LRP 30 making substantially more power then it has any right to be, but even still I am going to try again with a .32 and see if I can get a clean run..I am going to install higher grade Swiss ceramics instead of the Chinese ceramics I was using....

If you wanted more juice get yourself a $16.00 harbor freight dial indicator then set your deck height to 0.4 mm...run a step cooler plug fatten the needle and hold on tight ! probably could go down to 0.3mm with 20% ( this will make a massive difference, especially with 20% ) actually a different design button with a smaller bowl would be ideal for the lower nitro, the stock Picco 28 bowl is sized more for 40% nitro ....


http://www.harborfreight.com/1-inch-...cator-623.html

1QwkSport2.5r

I'd be curious to see what the Picco does. My head clearance is set with just two .2mm shims currently. I'm already running P6S plugs - I want to keep running these for awhile. They seem to work pretty well so far. I will eventually swap in a Turbo head button from the Schumacher .28. Any idea if the chamber is tighter/smaller on the turbo head than the standard head?

FWIW, my Picco isn't stock. It's had some work done to it.

supertib

Careful with doing "work" to these engines..I would estimate that 90% of what is commonly believed to increase power actually ends up losing power once you have the ability to test it. Without any question there is nothing you can do to a Picco 28 modification wise that is as effective as just properly setting the deck height as I am instructing....Increase crank timing, increase sleeve timing, cut flow fangs, smooth the crank, none of that will do a dam thing until the head is set right.........Be very very careful doing fangs and flow cuts as they usually lose power...in fact the more work done to the outside of the sleeve it seems the more power is lost...On my modified the outside of the sleeve is left as it comes from factory..... Basically I am going to say that 90-95% of modified engines sold over the last decades will produce less power and a less desirable powerband then the stock engine it started as....When you consider I am one of the only ones to ever build and master using a dyno system it kind of makes sense...as these engines are extremely sensitive and without a dyno to test the chances of someone increasing power using a dremel is near impossible........ Now of course you can alter the powerband and change the way it feels, but once you see the dyno graph you usually end up seeing that in order to get the top end boost you have narrowed the powerband considerably with a loss of peak torque values.....

So in closing the #1 thing that should be done to any nitro is set the deck height, there is nothing else you can do to increase power and RPM as much as simply setting the deck height....I shouldn't even be telling people this stuff LOL !

1QwkSport2.5r

Sorry.. No fangs. No funky stuff. Surely getting the head clearance right will add power... But to a point. Tailoring the engine to the pipe/manifold will surely show some benefits as I've found. FWIW - my liner looks 98% stock. Also FWIW - smoothing out the powerband some and adding some on the top was what I was looking for. It runs really well, is quite predictable, and gets better fuel economy than the SH did with a whole load more top end. It feels brilliant to me.

supertib

As i say..there is nothing you did or can do that will match what just setting a proper deck height will do ..in other words if we were to compare the 2 engines...yours with whatever mods you could imagine less setting the deck height, and mine which was 100% bone stock with just the shims adjusted...my engine would be substantially more powerful...The further you are from the heads sweet spot the more power you will lose...it is the #1 most critical thing when it comes to making power with these engines bar none !


.

Nitrovein

The 'funny' part is that when you get it just right with the head there is little difference between what nitro percentage you can run. It's not like the manual often say, that you need to add shims if you increase the nitro percentage, when it's right that is.
But some crappy oils don't like it though, it separates the good fuels from the bad.

supertib

You may already have the deck height set correctly by what you have done but without proper measurement there is no way to know for sure..a dial indicator is the only way accurate enough to set it perfectly...with only 20% nitro this step is critical... these engines can be all over the map depending on tolerance and generation... from as low as 0.5 mm all the way to 0.8 mm .....with 20% on a fully broken in engine you can run 0.3 mm the power difference between 0.8 mm and 0.3 mm would be about 40%, torque would be measurable 20-25% increase ... so this is why I so strongly urge you to spend $16.00 and double check your deck height properly...if your on the money your on the money..but if your not you just leaving free power on the table for nothing.... Basically in the end run the head as tight as you possibly can till the engine starts acting up.... the tighter you can make it run properly the more power it will make ..I guess you don't need a indicator to do it that way, but a indicator makes it great to set a known reference point................

supertib

You can run high nitro with super tight deck height as long as the bowl volume isn't too small.... most buttons today are fairly relaxed and set for 30% or even 40% nitro.... s when you only run 10% they lose a bunch of power if the deck height isn't tightened up whereas the higher nitro makes more power with a looser deck height....If the bowl is larger then both 20% and 60% can run the same tight deck height, but if the bowl is too small then the higher nitro starts acting up with the tighter deck height .......... but as I say all the big block offroad engines seem to be at a minimum a 30% sized bowl and some of the bigger engines can 60% with a tight head ..... I Just dd some testing on the Mito 35WC and tried both the 30% and 16% bowl and as figured the 16% bowl would not run right on a tight tolerance and 30% nitro......when I added a shim the 16% bowl ran properly on the 30% but did not make the power of the 30% bowl on the tighter head ....it seems the magic sauce is having the button to piston clearance as tight as possible and if needed adjust bowl volume accordingly to achieve it

Nitrovein

True, I have only tested fuels between 20-30%, so I'm not sure on how it acts beyond that.
I have found that with a "hot" setup it far more critical with what fuel you run and the right type of glow plug.
But getting the squish surface and bowl shape and volume right is a must to get it to run good with a variety of fuels on low squish clearance.
I believe some boat folks run extremely tight squish and pretty high compression with loads of nitro, but they have water cooling!

1QwkSport2.5r

I think it pertinent to compare a stock engine to the same engine modified if one is comparing the manifolds. Obviously the modified engine will have higher timing and a bigger carb among other things...

controlliner

Port size, timing and angle. Crank port timing and duration.

supertib

Been a little while,,but I finally got to testing the Modified Boost 28 on several manifolds.... 41032 Offroad, Stock LST, Picco Onroad and the Novarossi 41017.... Here are the graphs for both peak power and Average power