I need some help I need to get a new engine for my HPI Super nitro that can beat a Nitro 4-tec 2.5. I appreciate any advice.

what are you looking to spend? It's all in the details...

but, here is a stupid answer for you:

http://www2.towerhobbies.com/cgi-bin...?&I=LXDAK2&P=7

I'm willing to spend like $200. I'm not looking to match speed but to beat it. Thanks for the suggestion though. I may still just purchase that since you bought up a good point.

Well, if I'm not mistaken the super nito doesn't come with a 2-speed. If that is an option part.. Grab that and the TRX.. Then just gear it up a little.

Add HPI Part 72516, this should be your first step.

http://www.hpiracing.com/graphics/parts/a911d.jpg

Whould you happend to know off hand how many HP the TRX 2.5 has? You are right the super nitro only comes with the 1-speed. So that is great advice.

1.35hp

Thanks. That will give me a better guideline for the engine that I want. What do you suggest for an engine in the 1.35 hp range? I was looking at the Serio .12 Outlaw SP12TRPPRO. It has 1.45 HP. Are you familiar with this engine and how does it compare to the TRX?

shouldn't have no problem with the sirio!!!!

Would you say that since the serio is a .12 with 1.45HP and the trx 2.5 is 1.35HP but .15 you have an advantage with the Serio? Thanks for all your help. I'm new to this forum and appreciate your assistance.

Max:

Engine Hp is not Black and White..

A 2hp Engine that can do 20,000 won't necessarily be faster than a 1Hp engine at 40,000... It depends on where it makes the power, and how long and high through the RPM band it holds the power.

Sirio is a great choice. So Is the trx, NR (any), OS CVR-X / .12TR, Fantom Fr12 / Fr15, Trinity Xp-12 (Not race legal), Orion Wasp .12 (not race legal)

Any of these will do...

What goes into Top Speed:

Rpm / Torque / Gearing

The engine is such a critical investment . Thanks for the advice I will now feel more sure with which engine to purchase. What engine do you run? Are any of these engines alot harder to break-in than the other?

I have heard that sirios in general are very sensitive to adjustments. But that may be because they are very well manufactured and respond to needle adjustments very well!

I think the Fantom is a VERY good choice. I have read many rave reviews about it being better than OS CVRs.

I'd take a serious look at that and definitely get the 2 Speed Transmission.
that should be less than $200 and you can beat the heck out of em and say "Maybe I just drive better" lol

ram

I run a Fantom fr15 and a Hpi .12ss. I don't have any personal experience with most of those engines, so your best bet is to do some searching and see what people say about them. I know the OS CVR-X is one of the hottest racing engine out, (That can be had for under 200) But if your not planning on racing, look into a turbo engine.. Cheap power, but well worth it...

BTW: If you want to beat a 4-Tec.. take it on a course with few straight lines... they hate turning...

Your going to wake the DDR demons for that one...

Thanks for the tip. It's not the first time I hear that the 4-tec's are hard to controll. I find my control to be an advantage especially on turns. I'll keep my ears(eyes) open for opinions on various engines.

Also.. dont forget to get a better pipe. A good motor will run like crap with a bad pipe installed.

You might wanna Check out www.novarossi.com and maybe www.rbproducts.com (for their pipes).

Novarossi makes some fairly insane engines!

Also.. please remember that HP is NOT everything!! There is no standard for testing, and on top of that these numbers say nothing about torque.

I would weight peoples opinions, reviews and experiences over the plain numbers alone.
Also, price says a lot about the quality of the engine!

Hope that helps
ram

If you want more speed, look into a 21 conversion kit from new era models (or from a myraid of different manufacturers) and a budget 21.

Will do. I have to make several changes from what I see. I need the 2-speed, the engine, and a better pipe. I have to price everything out but it should remain in my range.

Take a look at the .21 conversion route. .21 engines have a LOT more torque than .12s for obvious reasons.

Just a good 21, a 2 speed, and a pipe.

I think your looking at about $200-225.

I think the gain in speed and power will be trememdous!
ram

A .21 will add an entire new dimesion to speed. Have you used one yet?

Err... I thought we were advising you to get a 21.. whom is this question directed to? lol

Sorry the question was for i8tweety. I was going for a .12 -.15 but he brought the .21 conversion which now sounds interesting also.

Oh! You were asking if he has used the conversion kit?
Has he used .21 engines? In a word..yes. He only has about 15 of em I think lol

If you can get the .21 conversion.. do it! Its well worth it man!

ram

I was just checking some prices and it seems to be $60 for the conversion kit. Not bad if you suggest it being a good investment.