Outer Limits 4x4 Board

what is the best size cfm gas research throttle body for a gq 4.2 non turbo

thanks

Best to call GR and ask them, but i'd reckon 400 CFM would suit ok.

Work out your volume displacement for your peak usable RPM, convert from cc to CF and work off that.

Coxy

Thats the one. GRA S400.

Thats the one. GRA S400.

narns1mav wrote:what is the best size cfm gas research throttle body for a gq 4.2 non turbo

thanks

i woudnt waste my money on gas research for a non turbo patrol

get an injected intake manifold and then just slap a impco 225 on it ( or a 200 because the 200 is easier to fit as part of the standard intake piping for an injected airbox)

Jes

Don't believe it, you'll improve drivability and peak power, I ran my old Shortie straight LPG with Gasresearch for 12 months prior to the turbo and it craps on a 300A impco. More than 10 % better. We did more N/A conversions to turbo conversions at Gasresearch when it was my business by about 100 to 1.

Joel

PGS 4WD wrote:Don't believe it, you'll improve drivability and peak power, I ran my old Shortie straight LPG with Gasresearch for 12 months prior to the turbo and it craps on a 300A impco. More than 10 % better. We did more N/A conversions to turbo conversions at Gasresearch when it was my business by about 100 to 1.

Joel

notice i did not mention the 300a ( for a reason )

the 200 or the 225 is plenty good enough, especially when you take into consideration the cost difference, and ease of setup/tune.

JEs

cost difference is negligible

NutterGQ wrote:cost difference is negligible

mate its far from negligable.

have you priced gas research stuff and priced a 200?

Jes

yeah I actually fix cars for a living (even if only part time now) and I have dealt with both systems and regularly still do. The research system allows mixtures at base, part and full throttle and with a good tuner can make it drive much better as your not always rich at one end and lean at the other, this usually means less fuel used and often better response as you dont have rich as buggery spots down low.

Price on either of these mixers/throttle bodies is hardly worth stressing over, also if money is an issue you can ebay the research stuff very cheap sometimes, rarely has wear, the non early gas research stuff has ball bearings on the butterfly shaft and they hardly ever wear/

When you use research on efi cars its better again as it lets you retain your dual fuel without imposing the intake tract restriction the 225 is.

Also if you decide to use the 200 or 225 they where on heaps of common shit, falcons, commys etc wreckers have lots of them usually worth very little.

i allready have a 225 mixer got it for 50 just watching this thread atm

btw gas research has long wait for delivery atm

thanks awaiting some more opinions

I currently have an Airod LPG system which is very basic. I am in the process of setting up an Impco 425 through a EFI manifold. I hope its worth all the trouble of making it fit!

create wrote:I currently have an Airod LPG system which is very basic. I am in the process of setting up an Impco 425 through a EFI manifold. I hope its worth all the trouble of making it fit!

whats the airod system giving you greif?
i
a 425 maybe overkill. the200 flows plenty enough for the 4.2..

the patrol i just sold, it had a impco system with 200 mixer and shaved head. it blew the doors off my other LWB and SWB patros which ran straight petrol!

Jes

I cant get a decent tune out of the airod system. The fuel economy is about 28l/100km. I got the impcoi 425 for a good price and thought I would adapt it. Im hoping that I get the economy down to at least 20l/100km. Using the EFI manifold I hope to get better low down torque also. I should have it running in about 2 weeks. I am also helping a mate setup his GU 4.8 with an impco 425.

create wrote:I cant get a decent tune out of the airod system. The fuel economy is about 28l/100km. I got the impcoi 425 for a good price and thought I would adapt it. Im hoping that I get the economy down to at least 20l/100km. Using the EFI manifold I hope to get better low down torque also. I should have it running in about 2 weeks. I am also helping a mate setup his GU 4.8 with an impco 425.

this what you need for the airod system
http://www.medauto.com.au/main_files/mixer.htm



or you can toss the screw adjuster on the vapour line and install a lambda control unit, either of these transforms the system.

Jes

Very interesting - I didnt know you could buy the airod thing. Mine just has the PCV vent removed and the gas plumbed in!

create wrote:Very interesting - I didnt know you could buy the airod thing. Mine just has the PCV vent removed and the gas plumbed in!

Really?
far out man, i havent seen one as bodgy as that before

it reminds me of the syetsms in europe before LPG was released there. They used to use 3.5g picknic bottles strapped in the engine bay, with a bbq regulator and a makeshift valve ( manual) and dump the hose into the regulator.
interesting setups

Jes

not trying to hijack thread but,iv got an airrod setup on my gu 4.5!
drivability and reliability is fantastic!! but no matter what iv had done to it they(gas tuners) cant get the eccomony anywhere near 20l/100km..closer to like 24l/100 when babying it
iv got all the mods like exhaust,filter etc...
how do i know if it has the mixer like the one in the link above?
as it sounds like it could solve my probs!

cheers

simcoe wrote:not trying to hijack thread but,iv got an airrod setup on my gu 4.5!
drivability and reliability is fantastic!! but no matter what iv had done to it they(gas tuners) cant get the eccomony anywhere near 20l/100km..closer to like 24l/100 when babying it
iv got all the mods like exhaust,filter etc...
how do i know if it has the mixer like the one in the link above?
as it sounds like it could solve my probs!

cheers

390 out of a tank of LPG aint nothing to be scoffed at in a patrol!
Jes