lrp.28 or .30 competition

[javier22]

hi i would like to know wat would be a better engine for my xl. lrp.28 spec 3
or lrp. 30 competition?

 

[Retrorod]

I would go with the LRP Z.28R Spec 3 over the .30. They are both good mills but I think that a .28 will be better on fuel than the .30 and will run just as fast as if not faster than bigger mills. Just my 2 cents though. :beer:

 

[xll-SavageX-llx]

It's hard to say. Where do you run, how do you run?
Track or at home just messin around.
I would take a .28 over a .30 any day, some guys would even take a .21 over a .28. It comes down to the RPM differences.

 

[javier22]

the .30 has more rpms rite?

 

[Mickey]

smaller engines are able to turn more rpms as they have less rotating mass

 

[javier22]

i c i guess ill stick with .28 then wat gear setup should i put on dat i want it to have good torque and top end

 

[Mickey]

47 spur and 17 clutch bell

 

[javier22]

how fast u think it can go with dat setup

 

[Retrorod]

there are some gear specs around hear I will see if i can find them

 

[Retrorod]

the lrp .30x competition is a bump start mill also

 

[javier22]

wats bump start?

 

[xll-SavageX-llx]

wats bump start?

It's a box with an electric motor in side and when you push down on the kit the fly wheel engages the electric and the motor turns the mill over your you.

[YOUTUBE]Q3wbJ1QO1hQ&playnext=0&list=PLD015995BBDE247C7[/YOUTUBE]
First few seconds show how it starts it.

 

[Retrorod]

I am sure that I will be corrected if I am incorrect, but you need a starter box that turns the fly wheel to start the mill, and that application is generally for truggys and will not work with a Savage. You can use a LRP ZR.30 Spec 2 with a Savage that is pull start, and the rpms top around 33,200, a Z.28R Spec 3 rpm is 33,000

 

[Retrorod]

lol! to slow to type on my part!

 

[xll-SavageX-llx]

I am sure that I will be corrected if I am incorrect, but you need a starter box that turns the fly wheel to start the mill, and that application is generally for truggys and will not work with a Savage. You can use a LRP ZR.30 Spec 2 with a Savage that is pull start, and the rpms top around 33,200, a Z.28R Spec 3 rpm is 33,000

MFGR specs aren't right FYI.
LRP Z .28R Spec.3 Truggy 1.87 @ 27,200 rpm 70.77 oz-in @ 25,600 rpm 42,800 rpm

Can't find the .30 specs. .28's and .21's will have more rpms then a .30.
Mickey already stated that in an above post.

 

[Retrorod]

So here is the info that I was talking about.... I do not remember who made this as I had saved it on my computer some time ago. So sorry about the credit to the author.

Typical Savage Speed Examples
This table shows some typical Savage gearing setups and the speeds you could potentially achieve, assuming a couple things. First, we're using a 6" tall tire. The original Savage tires were about 6-5/16" tall, but Dirt Bonz are more like 5-5/8" tall, so we're using 6" as an average height. Also, we're using stock diffs and 30,000rpm as the max engine speed. Some engines will go higher, but no-load speeds are much higher than what an engine can spin while pushing a heavy truck down the road. Use these numbers for comparison purposes and for theory, not as a guarantee of a certain speed. If you swap to CEN ring and pinion gears with no other changes, your speed will increase by 14.5%. So find your gearing combo and transmission type to get your 30,000rpm speed, and if you have CEN diffs, multiply that speed by 1.145.
Note Spur Bell Ratio 2-Speed Top Speed* 3-Speed Top Speed* HS 3-Speed Top Speed**
- 52 12 4.33 24.3 MPH 24.4 MPH 27.9 MPH
- 52 13 4.00 26.3 MPH 26.4 MPH 30.2 MPH
- 52 14 3.71 28.4 MPH 28.4 MPH 32.5 MPH
- 52 15 3.47 30.4 MPH 30.5 MPH 34.9 MPH
- 52 16 3.25 32.4 MPH 32.5 MPH 37.2 MPH
A 52 17 3.06 34.4 MPH 34.5 MPH 39.5 MPH
A 52 18 2.89 36.5 MPH 36.6 MPH 41.8 MPH
A 52 19 2.74 38.5 MPH 38.6 MPH 44.1 MPH
A 52 20 2.60 40.5 MPH 40.6 MPH 46.5 MPH
B 49 12 4.08 25.8 MPH 25.9 MPH 29.6 MPH
- 49 13 3.77 28.0 MPH 28.0 MPH 32.1 MPH
- 49 14 3.50 30.1 MPH 30.2 MPH 34.5 MPH
- 49 15 3.27 32.3 MPH 32.3 MPH 37.0 MPH
- 49 16 3.06 34.4 MPH 34.5 MPH 39.5 MPH
- 49 17 2.88 36.6 MPH 36.6 MPH 41.9 MPH
- 49 18 2.72 38.7 MPH 38.8 MPH 44.4 MPH
A 49 19 2.58 40.9 MPH 41.0 MPH 46.9 MPH
A 49 20 2.45 43.0 MPH 43.1 MPH 49.3 MPH
B 47 12 3.92 26.9 MPH 27.0 MPH 30.8 MPH
B 47 13 3.62 29.1 MPH 29.2 MPH 33.4 MPH
B 47 14 3.36 31.4 MPH 31.5 MPH 36.0 MPH
- 47 15 3.13 33.6 MPH 33.7 MPH 38.6 MPH
- 47 16 2.94 35.9 MPH 36.0 MPH 41.1 MPH
- 47 17 2.76 38.1 MPH 38.2 MPH 43.7 MPH
- 47 18 2.61 40.3 MPH 40.5 MPH 46.3 MPH
- 47 19 2.47 42.6 MPH 42.7 MPH 48.8 MPH
- 47 20 2.35 42.6 MPH 42.7 MPH 48.8 MPH


NOTES:
A - Likely will not fit Savage without mods (gear combo is too large)
B - Likely will not fit Savage without mods (gear combo is too small)
* - "Top Speed" is controlled by many things, as stated above, thus these speeds are intended for comparison purposes to help with clutch bell and spur gear changes, and also to compare the potential top speed difference between the available Savage transmissions.

 

[javier22]

k kool

 

[Retrorod]

MFGR specs aren't right FYI.
LRP Z .28R Spec.3 Truggy 1.87 @ 27,200 rpm 70.77 oz-in @ 25,600 rpm 42,800 rpm

Can't find the .30 specs. .28's and .21's will have more rpms then a .30.
Mickey already stated that in an above post.

Hey my bad... I will just put that in my pipe and smoke it... Just trying to help man. :beer:

 

[javier22]

its kool man thanks guys

 

[Retrorod]

No prob. man any time!