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4JA1-L

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4JA1-L

Postby LeRoux » Tue Jun 27, 2017 10:19 pm

Hi Guys...
I need some help please. I recently installed the 4JA1-L engine. There is a turbo/compensator fitted to it, but no intercooler.
I need a bit more power, especially on the uphill parts of our roads here in South-Africa.
Can I bolt on an intercooler to increase the power, and if so, would I then have to change the pistons and injector pump also?
Any advice please
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Re: 4JA1-L

Postby geeves » Wed Jun 28, 2017 5:44 am

intercooler on its own wont do much but it will allow you to increase boost and fuel for more power
Sanding your knuckles before starting work can help. That way you cant skin them
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Re: 4JA1-L

Postby LeRoux » Wed Jun 28, 2017 3:34 pm

Thanks for the info geeves.
I heard of some guys increasing the boost from 0.3 to o.9 and even 1.8 just by adding a spacer washer behind the spring of the actuator. :o
1.5mm = 0.9 bar boost
3mm = 1.8 bar boost :shock:
Not sure I need that much boost lol.
The other option if you opted to go without the intercooler, is to advance the timing to keep the EGT down then open the diesel flow. This way you could achieve 20% more KW and 26% more torque. (Achieved on a Dyno)
What option would you recommend?
LeRoux
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Re: 4JA1-L

Postby geeves » Thu Jun 29, 2017 5:43 am

Option 2 but still fit the intercooler
Sanding your knuckles before starting work can help. That way you cant skin them
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Re: 4JA1-L

Postby geeves » Thu Jun 29, 2017 1:50 pm

Thinking about your boost. We tend to think about boost in PSI despite everything else in metric. From memory 2 bar is as close to 30psi as it needs to be for working this out. We dont have a lot of 4ja1 engines here with most being 4jb1 4jg2 4jh1 and 4jj1 engines. The factory setting for all of these was 10psi or 0.6 bar but pretty much everyone is running 15psi or 1 bar without issue. Much higher than this means playing with the boost relief valve on the inlet manifold.
As a quick test try clamping the waste gate to turbo line and see how this reacts. Increasing boost without increasing fuel may give a little extra power as the boost compensator will adjust this. It should make little if any difference to egt although it may even drop
Sanding your knuckles before starting work can help. That way you cant skin them
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