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4jg2 pump conversion, IDI to DI and Right or Left spin

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4jg2 pump conversion, IDI to DI and Right or Left spin

Postby muffinmonsta » Sun Jun 17, 2018 12:08 am

Good day Gents,
is it possible to convert a 4jg2t idi pump to work on a 4jb1t?.
if possible what mods are needed?
Last edited by muffinmonsta on Tue Jun 26, 2018 2:36 am, edited 1 time in total.
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Re: 4jg2 pump conversion

Postby tonkamu » Sun Jun 17, 2018 1:34 pm

Won't the map be way out? the computer is for a 3.1 with indirection injection different size injectors. But im not an expert
But the answer is yes anything is possible hehe
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Re: 4jg2 pump conversion

Postby muffinmonsta » Sun Jun 17, 2018 2:04 pm

tonkamu wrote:Won't the map be way out? the computer is for a 3.1 with indirection injection different size injectors. But im not an expert
But the answer is yes anything is possible hehe


no computer all mechanical
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Re: 4jg2 pump conversion

Postby isuzurob » Sun Jun 17, 2018 2:20 pm

The cam plates are different, and the plunger is meant to be bigger in the 3.1 pump but they bolt straight on to a 4jb1 and work well, well mine did anyway
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Re: 4jg2 pump conversion

Postby muffinmonsta » Mon Jun 18, 2018 11:47 pm

Planning to use a G2 pump with the B1 cam plate. But will the injection pressure get up to B1 level?
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Re: 4jg2 pump conversion

Postby isuzurob » Tue Jun 19, 2018 12:39 pm

Mine ran ok with a standard 4jg2 pump on a 4jb1, just slapped it on and was away
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Re: 4jg2 pump conversion

Postby muffinmonsta » Thu Jun 21, 2018 11:17 am

OK then that sounds good, because for the life of me I can't get my hands on a working jb1 injection pump
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Re: 4jg2 pump conversion

Postby tonkamu » Sun Jun 24, 2018 4:05 pm

Hey guys, on the mech pump for 2.8 can you control how much boost with the compensator adjusted and tap screwed in if the turbo is free spooling/waste gate not connected?
Currently only reaches 18 psi with wastegate not connected the fuel screw has been screwed in quite abit that my idle screw is no longer in use and idles at 800. My understanding of the boost compensator is limited and I've never touched it but I bought this car with factory turbo that boosted to 18. I've fitted a vf10 with vf10 exhaust housing and 2.5 inch downpipe since then. increase in power has been insane, the whole front lifts up and bottom sits down at 90kph flooring it, no smoke. I have a boost tap I can only get 10 psi with the boost tap with 12 turns out when its connected. I'm just trying to understand why its only 18 psi when boost tap not connected and not greater, whats controlling it?
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Re: 4jg2 pump conversion

Postby geeves » Mon Jun 25, 2018 3:25 pm

Have you removed the pressure release from the inlet manifold? This should be releasing at 16psi though so could be where the boost is going
Sanding your knuckles before starting work can help. That way you cant skin them
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Re: 4jg2 pump conversion

Postby tonkamu » Mon Jun 25, 2018 3:37 pm

hey geeves, yes its been taken off and blanked up. How do other people get 30 psi with no wastegate, I can't turn fuel in anymore as the idle/throttle is hitting the stop assembly. Is the adjustment at the compensator in order to get more fuel in under boost thus making more psi? cheers
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Re: 4jg2 pump conversion

Postby geeves » Mon Jun 25, 2018 5:14 pm

I doubt 30 can be done in a street drive-able trim. It would have to be a big turbo so without fancy variable vanes etc its going to be rubbish at low revs. You could look for obstructions in gas flow ie air intake system exhaust system air filters etc. All will choke the turbo. Also you might be at the limit of the injectors. If they cant inject more fuel then the only answer is bigger injectors. By the time you have a 4 inch no bends or mufflers exhaust and a straight 5 inch inlet pipe with no air filter 50% larger injectors and up the pumping capacity you should go a little better. Then add lpg injection and Mr Plod will confiscate your car under boy racer rules but a 13 second quarter in a 2 ton 4wd always looks impressive.
The other possibility is that your boost gauge doesnt read above 18
Sanding your knuckles before starting work can help. That way you cant skin them
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Re: 4jg2 pump conversion

Postby muffinmonsta » Tue Jun 26, 2018 2:33 am

Are all Belt driven pumps right spin and all gear driven pumps left spin?. Looking at the Belt and the Gear driven 4j engines with the timing covers removed it would seem that way.
i have eyes on a gear driven 4jg2 pump but i can't see the VE4 part number so i don't know if it is left or right spin
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Re: 4jg2 pump conversion, IDI to DI and Right or Left spin

Postby isuzurob » Tue Jun 26, 2018 7:13 pm

All gear driven pumps run opposite to belt driven, if you get complete engine you can just swap everything onto your engine
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