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Old 11-12-2019, 07:44 PM
Rhill Rhill is offline
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Default Engine selection help

Ok guys so I have a buggy that I acquired in a trade. It currently has a gx390 on it. But the buggy is pretty heavy prolly 800lbs or so give or take. Does anyone know of a motor thatís stronger or makes more power than the gx390. It rolls it pretty good on flat ground but not so good on up hill and stuff. Any tips or advice would be great.
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Old 11-12-2019, 07:47 PM
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Well let’s see some pictures of what you have going on:
-transmission
-whole buggy
- gears


It could be that it has the wrong gearing. So let’s see what you have got and we can go from there. Starting the process of elimination which could turn out that you in fact do not need a new engine and you could save a lot of $$
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Old 11-13-2019, 11:49 AM
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Quote:
Originally Posted by 950speed View Post
Well letís see some pictures of what you have going on:
-transmission
-whole buggy
- gears


It could be that it has the wrong gearing. So letís see what you have got and we can go from there. Starting the process of elimination which could turn out that you in fact do not need a new engine and you could save a lot of $$
Ok so it has a torque converter and the sprockets the small one has 8 points the back has 62 and it has 12 inch tires
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Old 11-13-2019, 09:10 PM
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Quote:
Originally Posted by Rhill View Post
Ok so it has a torque converter and the sprockets the small one has 8 points the back has 62 and it has 12 inch tires
12" you sure?

with that info it'll move the heavy beast just fine..
not fast.. but fine
in fact it'd do so with way more than 2000 lbs !!

KartInfo by kartcalc.net:
Code:

KART
RW diameter: 12 in | 30.48 cm Total weight: 2204.62 lbs | 1000 kg
ENGINE
Original HP: 13 Asummed HP: ~13 Torque: 18.97 ft lbf | 25.71 Nm RPM: 3600
TRANSMISSION
Final ratio: 7.75:1 TC type: series 40 Lowest ratio: 18.83:1 Highest ratio: 7.75:1
PERFORMANCE
Max Wheel Torque: 357.07 ft lbf | 484.12 Nm Min Wheel Torque: 146.96 ft lbf | 199.25 Nm Acceleration: 6.33 ft/s≤ | 1.93 m/s≤ Top Speed: 16.58 mph | 26.69 km/h
So excuse me, but I think you mistook wheel diameter for rim diameter
those look like 22" on 12" rims to me
[EDIT]
shoot 12" rim bearclaws are 25" in diameter...
let's fix that...

and with that gear ratio is off

you'll need more teeth on the axle...
KartInfo by kartcalc.net:
Code:

KART
RW diameter: 63.5 cm | 25 in Total weight: 450 kg | 992.08 lbs
ENGINE
Original HP: 13 Asummed HP: ~13 Torque: 25.71 Nm | 18.97 ft lbf RPM: 3600
TRANSMISSION
Final ratio: 9.5:1 TC type: series 40 Lowest ratio: 23.09:1 Highest ratio: 9.5:1
PERFORMANCE
Max Wheel Torque: 593.64 Nm | 437.85 ft lbf Min Wheel Torque: 244.25 Nm | 180.15 ft lbf Acceleration: 2.52 m/s≤ | 8.27 ft/s≤ Top Speed: 45.36 km/h | 28.18 mph
PROBLEMS
You might burn your clutch/belt! Gear ratio too high! Suggested final ratio: at least 9.7:1
something like 77-80 teeth should work fine on the axle if you keep the 8T TC sprocket

if you want to keep the ratio fixed..
you need a 21hp engine to move the 992 total weight I assumed above.
the more the better

'sid
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Old 11-12-2019, 08:17 PM
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Ok I’ll have to take some pics of it in the morning when I get to the shop. I can get pics of the buggy and gears but I’m not sure about the transmission not to sound dumb but I didn’t know it had one
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Old 11-12-2019, 08:18 PM
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As already mentioned what will help us determine a solution to your problem:

1. What is getting power to the wheels? CVT (what kind)?

2. What kind of gearing is on there now?

3. Tire size?

You probably want close to 8 or 9:1 gearing to move that much weight around.

Pictures of the machine and drivetrain will be helpful. Most engine swaps that will help out will require modifications to the frame and may not be cheap.
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Old 11-12-2019, 08:19 PM
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It’s probably either a clutch or a torque converter, it’s wha connected between the engine and the axle


The chain connects the trans to the axle.

Transmissions don’t have to be a thing that shifts gears. It can be one single gear, it’s all used to transfer rotational energy in our case
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Old 11-12-2019, 08:45 PM
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Have you thought about a predator 670cc? It makes more power and torque than the 390cc but you'll need a 40 series TAV to not burn up belts
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Old 11-12-2019, 09:00 PM
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With the 670, its huge in comparison to a GX390 and will require extensive modifications. Plus a 40 series may only hold up for a bit. A larger CVT will be better suited, but all that comes at a cost, about $1500 for engine and suitable CVT.
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Old 11-12-2019, 09:59 PM
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800 lbs?
What's it made off?? lead pipe?

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Old 11-12-2019, 10:30 PM
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How about this bad boy?

38ft-lbs of Torque @ 2200rpm!
Shipping Weight = 89lbs
$899

https://vegascarts.com/collections/e...lf-cart-engine
Attached Images
File Type: png 625Measurements_1486x875.png (58.2 KB, 4 views)
File Type: jpg 625cc 23HP Golf Cart Engine[1].jpg (101.7 KB, 2 views)
File Type: jpg 625_1_1088x768.jpg (76.0 KB, 1 views)
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Old 11-12-2019, 10:41 PM
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625cc single cylinder?
oomph I say.. OOMPH!

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Old 11-12-2019, 10:58 PM
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Quote:
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625cc single cylinder?
oomph I say.. OOMPH!

'sid
That and a good clutch setup it would pull my Civic around, heck it might pull my F-350. But I'd miss the turbo spoolin' up, lol.
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Old 11-13-2019, 04:31 AM
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Oof that's a big single cylinder
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Old 11-13-2019, 05:45 AM
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Thumpers are great for the power. When you half to pull down a house with a golf cart, you get a thumper.
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Old 11-13-2019, 05:51 AM
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Thumpers are great for the power. When you half to pull down a house with a golf cart, you get a thumper.
Do briggs 8hp i/c's count as thumpers or? But dang over 600cc ohv single cylinder what do you put that on, a Chevy c10? Lol?
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Old 11-13-2019, 06:23 AM
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Nah, I'd use the one cylinder on my drifter (200 pound kart with 23hp, what could go wrong?), and a blown 454 with just a bit on NOS in the c10. Wet system not dry of course.

And we could use some pictures of the drive setup and some sprocket tooth counts.
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Old 11-13-2019, 06:36 AM
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Quote:
Originally Posted by Budget GoKart View Post
Do briggs 8hp i/c's count as thumpers or? But dang over 600cc ohv single cylinder what do you put that on, a Chevy c10? Lol?
I have no idea on displacement cut off for a thumper or not. I think it's generally just a nickname for single cylinder engines.
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Old 11-13-2019, 09:21 AM
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with these guys.
That GX390 will move that buggy just fine, it all depends on gearing.

A 625cc single cylinder!!! Can you imagine the ridiculously loud exhaust and the vibrations!!!
But man, that thing would MOVE!!
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Old 11-13-2019, 11:59 AM
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Nice... a new contender for the big block crowd...Odd.. doesnt say shaft size....

Looks like they use the head off of a 670 onto a modified big block....
Cool.... heavy though... needs a gastank..
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