For the love of a tractor engine: The life and times of the 18R-G

[hosking1991]

fixed for ya

[Omegaman]

Can anyone assist with these injector figures.

18rgeu gives @125hp so
give it 50psi fuel
duty cycle 50%
= 28.41lbs /298.3cc injectors
giving that I can use 324cc inj / 28.55lbs

or go for 160hp with mods done on motor
.45 psi
.80 duty cycle
22.2/236.25cc inj
which means i can use 240cc injectors/

or 200hp
.50 psi
.60 duty cycle
41.67lbs/437.5cc
meaning I can use 460cc/43.77lbs

or 200hp
.45psi
.80 d/cycle
28.13lbs/295.31cc
meaning. Use the 324cc / 28.55lbs

Does this make sense?
These so many senario's, but the HP side is the variable on the above.
This can be achieved with emanage piggyback only or stand alone comp.
which way would be te most efficient and desirable scenario?
__________________

[o_man_ra23]

45psi is the most realistic of your pressures. Normal is about 40psi for a stock system.

50-60% duty at max power is silly, as you are likely to have rough idle. 70-75% would be optimum, with 80% at the high limit.

Your power figures, are they flywheel or rear wheel?? What other engine mods have you got to help get these power figures?? Your cam profile, compression ratio, motor balancing, forced induction, exhaust size, port profiling, and many other things will determine the power output of the motor, then the intake just needs to support the capabilities of the rest of the motor. So work out the engine's mechanical ability first, and come back with a realistic max power figure, and also work out what pressure your fuel pressure regulator works at. Once everything else is a constant, injector size is only a simple mathematical equation away.

[Omegaman]

I thought as much on most of these you have mentioned.
The hp at 125 and 145 are the factory suggested for these motors.
Without dynoing to start with will be hard to determine output.
I guess I'm going rule of thump, but suggesting at 145hp with 9.7 comp, balanced crank, 2.25 exhaust and more might bump up to 160hp/119kw

giving mr the optimum of
160hp with mods done on motor
.45 psi
.80 duty cycle
22.2/236.25cc inj
which means i can use 240cc injectors

this may be a good starting point,then trying the
or 200hp
.45psi
.80 d/cycle
28.13lbs/295.31cc
meaning. Use the 324cc / 28.55lbs

Sounds fair?

[RA23]

A while ago someone (was that you Witzl?) posted a photo of the 18RGEU thermostat housing, indicating what all the sensors were. I have searched for a while but cannot find it anymore.
Can someone post a picture or photo explaining what they are ?
Thanks,
Edwin

[o_man_ra23]

I would use the 324's if you have a decent resolution on your ECU. 80% will start heating up your injectors a touch more than I would want.

[Omegaman]

O-man-23
I will start with the 45psi at 70% duty cycle
flow rate is 32.14/337.5cc reccommended. So the 28.55lbs/324cc will do.

thanks buddy.

[o_man_ra23]

You will have a little bit of room for error then, so the duty cycle may creep up, but should stay out of the danger zone. Also, you may be able to get a bit more pressure in the line, depending how your pressure regulator works.

[RA23]

With some info on this site (Witzls photos) I worked out all connections to my 18RGEU plenum, except for the bit indicated with an arrow in the picture.
Anyone know what this is?
Can I safely rip it out?
Attachment 7405

[Omegaman]

This is part of the air conditioning, I believe. Not required.
Mine has been blocked, as in your pic.

While your sussing your connections.
Where have you connected the thicker vacume hoses under the plenum.
One goes from the intake maifold to the bottom of the throttle then T's of both to ?

[Steve M]

Yeah, that's the idle-up for the air conditioning. Keep it if you have air conditioning, sacrifice it to the gods of weiht reduction if you don't.

Do you have one of those big tubes under the plunum going to the block breather via a 1-way ball valve?

[Omegaman]

[QUOTE=Do you have one of those big tubes under the plunum going to the block breather via a 1-way ball valve?[/QUOTE]

I have the 1 - way ball valve, which is not connected anywhere. before dismantling I believe it was connected, but for the life of me, I don't know where. Its hard to see now that the engine is in.
As I said. One end is to the manifold, the other to the throttle body and the other was where?

[RA23]

This is part of the air conditioning, I believe. Not required.
Mine has been blocked, as in your pic.

While your sussing your connections.
Where have you connected the thicker vacume hoses under the plenum.
One goes from the intake maifold to the bottom of the throttle then T's of both to ?

OK, thanks guys, it will disappear

About the thick vac hose, that goes to the fast idle valve and from the fi valve down to a T junction, the small dia side of the T goes to the airco valve (as per yellow arrow in my previous mail) and the big dia vac hose goes back up to just before the throttle (you can just see that in my pic between the front of the fuel rail and the TPS.

This means I will get rid of the T piece and plumb the f-idle straight to the front of the throttle.

I have no ball valve, don't know what you mean??

Hope this helps,
Edwin

[Sagluren]

hey i blew my head gasket last night and need to know if the 18rc and 18rg share the same head gasket, i need it fixed today as it is my daily. i know i am going to get yelled at for not searching, but i never find what i look for anyhow.

cheers sam.

ohhh by the way i got the 18rg in the ra40. tis f*cking awesome, except from the cheap gasket i used.

[hosking1991]

18r hg can be used but the timing cover bolt holes dont line up
i couldn't imagine a acl 18rg head gasket would be to expensive if you can get trade prices