Straight Pipe

A

Alaskanassasin

Senior Member
Site Supporter
A earlier post reminded me of a question I've had for awhile.
Are there many straight pipes out there? Does it sound awesome? Increased performance? Just curious.
One of the mufflers broke off on my Cummins A few years back so we just decided to cut them all off and straight pipe it. my fuel economy went way up as well as performance, and it sounded awesome especially pulling a loaded dump trailer out of the rock quarry. After a few old people scowled at me and a few kids cried when I drove by I put a muffler from summit racing on it :).
 
R

Rogerwh0

Member
I had mine straight piped for about 2.5 minutes after I put my turbo on. It was extremely noisy. I ended up putting on a straight through muffler, it is still fairly noisy but tolerable. I can send you a video if you would like. I am actually going to put in a better muffler this week.
 
L

Lee1935

Active member
To get away from the spark arrester I've been toying with the idea of a muffler for a 28-40 hp tractor.

I suspect that a straight pipe on the little engine might affect the fuel ratio which is something above my pay grade. I do know running any engine too lean can be expensive☺
 
A

Alaskanassasin

Senior Member
Site Supporter
Rogerwh0 said:
I had mine straight piped for about 2.5 minutes after I put my turbo on. It was extremely noisy. I ended up putting on a straight through muffler, it is still fairly noisy but tolerable. I can send you a video if you would like. I am actually going to put in a better muffler this week.
Click to expand...

Can you post it on here?
 
A

Alaskanassasin

Senior Member
Site Supporter
Rogerwh0 said:
I had mine straight piped for about 2.5 minutes after I put my turbo on. It was extremely noisy. I ended up putting on a straight through muffler, it is still fairly noisy but tolerable. I can send you a video if you would like. I am actually going to put in a better muffler this week.
Click to expand...

Any thoughts on the turbo? Worth the money? Way more power? Thanks!
 
A

Alaskanassasin

Senior Member
Site Supporter
ovrszd said:
Good question. This is an opinionated subject. :)
Click to expand...

Thanks Richard! I am truly interested, I could be convinced to get one, sounds like a good winter project, however i think they are around $1,400 so for that kind of money.... well is it worth it?
 
O

ovrszd

Well-known member
I've read some horror stories about engine damage if not managed correctly. I've also read some good reports. I don't consider myself knowledgable enough to build my own system. I'd like to have the added power but so far the risks have scared me off.
 
C

Colorado_High

Member
Lee1935 said:
To get away from the spark arrester I've been toying with the idea of a muffler for a 28-40 hp tractor.

I suspect that a straight pipe on the little engine might affect the fuel ratio which is something above my pay grade. I do know running any engine too lean can be expensive☺
Click to expand...

There is no concern about increasing air flow causing the engine to run lean. A diesel engine always runs overall fuel lean. As a diesel engine runs at higher power, the air:fuel ratio (by mass), or A/F, reaches a maximum of about 20 or so, and begins to smoke excessively at lower A/F. At idle, the A/F ratio can be 100 or so. The fuel jet is sprayed into hot air, igniting the fuel and it burns in that jet near stoichiometric A/F (about 14.6), but excess air is required to burn off the unburned particulate matter (smoke), unburned hydrocarbons, and CO, and to limit peak temperatures in the cylinder. The lower in-cylinder temperatures contribute to allowing diesel engines to run at peak loads continuously, while it is harder on gasoline engines to run at full load for long periods.

Lee
 
C

Colorado_High

Member
ovrszd said:
I've read some horror stories about engine damage if not managed correctly. I've also read some good reports. I don't consider myself knowledgable enough to build my own system. I'd like to have the added power but so far the risks have scared me off.
Click to expand...

Richard,

Adding a turbocharger and not changing the fueling rate just increases the airflow through the engine, but does little to increase power. At high altitudes, this allows the engine to operate without smoking. Typically, the injector pump is adjusted to increase the fueling rate slightly, and this does increase power in proportion to the amount of fuel increase. A more significant power increase could be obtained by replacing the injector tips with higher flow tips, but this would be risky as this would increase in-cylinder temperatures and possibly lead to piston damage.

Most of the existing turbo systems for the Kubota RTV's do not include an intercooler, so the inlet air temperatures are increased due to the pressure increase, limiting the amount of extra fuel that can be added without smoking since the mass flowrate of air is reduced when the air temperature is increased.

Lee
 
1

10-e-c-dirt

Active member
Just curious, Has anyone turned the FI pump up, advanced the timing, higher flow injectors, w/ pyrometer EGT gauge for safety
 
O

ovrszd

Well-known member
Colorado_High said:
Richard,

Adding a turbocharger and not changing the fueling rate just increases the airflow through the engine, but does little to increase power. At high altitudes, this allows the engine to operate without smoking. Typically, the injector pump is adjusted to increase the fueling rate slightly, and this does increase power in proportion to the amount of fuel increase. A more significant power increase could be obtained by replacing the injector tips with higher flow tips, but this would be risky as this would increase in-cylinder temperatures and possibly lead to piston damage.

Most of the existing turbo systems for the Kubota RTV's do not include an intercooler, so the inlet air temperatures are increased due to the pressure increase, limiting the amount of extra fuel that can be added without smoking since the mass flowrate of air is reduced when the air temperature is increased.

Lee
Click to expand...

Good response Lee. Mirrors what I've read regarding turbo installs. To get power fuel is added thru different injectors. Poston melt down is the most common failure with a turbo install.
 
R

Rogerwh0

Member
When I installed my turbo I increased the timing and fuel delivery just a tiny bit. I built my own turbo kit but I followed SWAG's instruction on the timing and fuel changes. I have almost 400 hours and a years time on it and would not own the machine without a turbo now. Kubota makes the same engine with a turbo on it so I was not too scared of a failure. Runs great and never runs out of power, the transmission still has to be used correctly but at least the engine stays strong. I forgot to get a video of the exhaust this weekend. I will try and get one tonight.
 
OrangeBuggy

OrangeBuggy

Active member
I turboed mine and made all off the adjustments it called for. Ran it around a half a dozen times to tweak it and am really happy with it.
 
OrangeBuggy

OrangeBuggy

Active member
On the straight pipe deal there are some videos on You-Tube of RTV's with stacks that sound nice. At lease I though they sounded pretty good, and I'm kind of old...lol.
 
OrangeBuggy

OrangeBuggy

Active member
Alaskanassasin said:
Did you use the swag
Kit?
Click to expand...

No, mine came from Orange Aftermarket. At the time I had a three year warrantee. Dealer called Kubota and asked if I could do this due too bad power loss when we go to the mountains and I didn't want to forfeit my warrantee at the time. They said go for it and I've been real happy with it. No problems.
 
S

shinnery

Active member
I'm near Abilene, but I spent a year in Amarillo in 65-66, and I know there aint no mountains in the Texas panhandle. LOL
Bryce
 
You must log in or register to reply here.
Top