cid

Okay everyone lets find me a new motor for my lst what I need is a motor that makes good power and is easy to tune that will last threw more than a gallon of fuel. I belive you get what you pay for. I just wont to make sure I get a qaulity motor for my money. if anyone has any suggestions I would like to hear them thanks for all replies.

titan66

the sh .28 is an awesome engine that has incredible power it is opn hobbypeople for 189 holds a tune very well!

cid

thanks for the reply who makes this engine and do you have any personal experiance with it

LSTGUY

Little bit of mooolaaa but...

[link=http://werksracing.com/product.do?sku=WRXLC30MT].30 nitro power[/link]

titan66

well i dont have one myself but if you check on the global hobbies forum for the mammoth they love this engine. It is made by a company called sh. It produces 3.5 hp at 28,000 rpm and from what im told holds a tune very well. you can find brand new ones on ebay for 165 i'll be getting one for my mammoth soon

Nitro10

Ditto on the SH. Great power, easy to tune and break in and its starts with a couple of tugs every time. I think the posted 3.5 horses @ 28k is actually a metric figure, so bet on it producing just under 3 hp.

supertib

the Mach 26 is an amazing engine if its broken in and tuned correctly, if you blew up the Mach you need to learn a few things before buying a better engine.....by the way a Mach 26 is made by SH engines so is the XTM lineup........and my XTM has been amazing....but there are some precautions that must be take before running these engines

titan66

nope it is actually rated at 3.5 hp go to hobbypeople.com and look it up

cid

the mach 26 was a okay engine but what i want is a great engine. the lst is not my first nitro truck and I am well aware of how to tune nitro engines.what i am looking for is advice on motors like a rb 28 and other motors in that class.I belive i got two gallons out of my mach 26.

thanks for all replies and keep the ideas coming

titan66

the wasp .28 is another option it has 2.95 hp at 41,000 rpm i think it is 170 looks like another good engine but im still gonna get the sh

spokman

My Feedback: (2)

Great.. Novarossi, RB ...

Naim.F.C

I thought the RB's had certain issues with their .28's?

rcblaze

What Precautions?

supertib

to get the most out of a Mach 26 first you must remove the engine and completely take the engine and carb apart, clean everything, replace the O-rings in the carb, reassemble the engine using ARO, grease the O-rings before inserting the needles, use RTR silicone to seal the Backplate and carb neck......this will ensure you have no metal filings in the engine(very common on a Mach 26) as well it will also ensure you dont have air leaks which is also a mojor problem on the Mach........


Now no matter what do not in any way turn the engine over till you are ready to start it, i see alot of guys pulling over new engines for fun, this will damage the piston and rod........the piston is very soft on a Mach 26 and when ts new the fit is extremely tight, by pulling the engine over you can distort the shape of the piston, once the motor has been heat cycled the piston will harden up as it goes thru a heat treating process.....


when you go to start the motor for the first time use a heat gun and pre-heat the engine to 220, then loosen the glow plug slightly and then start the engine, and from there follow your normal break0in procedure

by doing these steps you will eliminate almost all problem associated with the Mach 26, and your piston seal will be proper and you should be able to get at least 5 gallons out of the motor, I get around 7 gallons on a XTM, When treated correctly the Mach will usually outpower a Pico 26, but if you dont treat it correctly, well you must know as you only got 2 gallons and likely were never happy with the performance......

Nitro10

Titan 66.....The larger bore engines dont produce peak power in that high rpm range. The 41k they post is the max r's that the manufacturer will post as a safe max rpm. All of the big blocks produce their max power in the upper 20k range.

First of all dont believe everything you read. Second of all use common sense. The .27 Sirio race (pullstart) 7 port makes more hp per cubic inch than any stock engine out there. Since it makes 2.9 hp and a tad less according to some reviews why would you think the SH 3 port makes another .6 horsepower? The SH diagram that comes with the engine boasts a number 3.5 @ 28k r's....but it does not say hp or horsepower behind it. 3.5 horsepower out of the SH .28 just aint happening

supertib

okay first the SH 28 should beat the Sirio 27, second the OS V-Spec is 2.95 hp out of a 21 so its got the Sirio beat...the Novarossi .28 is 2.9 hp with only 3 ports.....Port count does not matter in the least for maximum power, port volume and timing matters alot more.....some short stroke engines require a higher number of small ports to acheive port volume without sacrficing reliability and the chance of catching the piston on the ports...where a longer stroke engine can safely use a lower number of larger ports....a single port with a 2cm sqaure volume is more efficient then 4 small ports equaling the same area......the SH 28 is likely hovering around 3hp with a very high tourque number.....dont discount the SH as its an amazing engine.........it has no problem competing with the big buck Itallian mills.....as i know my 24/7 pro was a very very close race with the Sirio 27, with the Sirio only edging the Pro out after 250 ft........and never put much faith in magazine dynos, as those guys have ZERO clue how to properly test a 2 stroke engine...they are actually quite pathetic in thier evaluations........you should never test a 2 stroke with any sort of tuned pipe, you should use a tuned length straight pipe, then when you are comparing engines you can see what the engine is actually doing, but they seem to stick one pipe on all the engines and assume the results are accurate, yet these engines are extremely sensitive to tuned pipes and each motor really should have different tuned pipes that are tested on each engine.....if you were to dyno a Polaris 600 and a Artic cat 600 but you used the Artic cat pipe for both motors i guarantee the Cat 600 would perform alot better, as the tuned pipe is responsible for up to 50% of the power output as well as determining the maximun operating RPM....yet these mags dont seem to have any clue of true fair testing.....so they are not really testing the motors they are testing motor pipe combos...but they dont ever post the results of different combos on each engine....the best way is to get a true baseline of each engine without the aid of a tuned pipe...for that you use a straight pipe and cut it to the length that achieves maximum power, this will alow scavenging without the power aid of the returning pulse wave, this testing will show you the actual output of the engine unaided by a tuned pipe...anyways cheers

titan66

actually they do claim 3.5 horsepower at 28,000 rpm that is not the peak rpm and i gaurantee that this engine has one of the highest torque ratings on any mt engine[>:] so i dont know how much the sirio .27 but im pretty sure it is well above 190 so for alot less you get an engine that has more horsepower and torque. Any questions

supertib

i myself dont go by claimed HP, except with the SH 25 pro they claim 2.75 and it was dynoed at 2.5 with very questionable testing procedures, but regardless the new 28 is claimed 3/4hp more by thier testing procedures so its sure to be at least 3 HP, and to make that HP at such low RPM the tourque must be insane.......i am big SH fan and i imagine this motor will rock, as my 24/7 pro was a missile in the Savage this new 28 must be amazing

titan66

yeah i want one but i have to get an lst first im sick of that ******* mammoth[:'(]

Nitro10

I disagree supertib. You will be lucky to show 2.5 horses out of out of any OS .21.

supertib

the OS V-Spec wasy dynoed high 2.9's in the HP department by a magazine, i think RC Car, sorry but this was done on the same dyno that did the Sirio 27......the new OS engines are low port count and have some of the highest HP per CC of any production engines...they are like a Honda i guess.....

supertib

http://www.rcnitro.com/rn/articles/dyno_vzbvspec.asp

okay here is the link to the article of the 3 HP OS .21........notice the port count and how big the ports are ?? and notice the high power per CC, you will see a lower port count big port engine will make more power.....hence the SH.28 is a monster...

Nitro10

Wow! I stand corrected. Looks like even though I have a SH in my Savage, Im still behind the times Good info Supertib. Didnt know they had a second version out now. All the older OS .21's always showed around 2.5 hp. Eating Crow now![:'(]