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Leaner Afr`s With Warmer Fuel Temps ?

Cameron_Datto
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Cameron_Datto Contributor

Cameron_Datto

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From what i can see happening is that the Air fuel ratio leans out with warmer fuel temps , After having engine running below 2000rpm for over a hour due to tuning , Iam finding the AFR`s are going leaner with water , air temps and battery voltage battery stable , When i felt the fuel tank temp ,its warm aprox 40 to 50 deg`s in temp , Iam using a external surge pot with the fuel return going back to the surge tank so that dosent help with the fuel temp increase and at idle your getting more warm fuel returned to the surge tank ,

So after having a think a the problem , I feel my 1st step is to try some ice around the surge tank , not to fix the problem , but to confirm the problem , then if this is postive step , i will try putting the return line back to the fuel tank ,

The other thing i was thinking is, new cars are now putting the fuel pressure regulators on the fuel filter outlets which are not in the engine bay , So you dont have a return line from your injector rail , this means returned fuel from the regulator isnt going to be as hot , i have only seen this system on Na engines , but can see why it wouldn`t work on a forced induction ,if the regulator is correct.

So has any one got any thoughts on the problem , Btw the car is a race car with only a 20 ltr fuel tank and using a vl turbo fuel pump ,its not a RB engine

I guess under normally running conditons its no going to be as bad , its just that iam running the engine to long around idle when iam tuning things , But if improve things all the better :(

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https://www.sau.com.au/forums/topic/159020-leaner-afrs-with-warmer-fuel-temps/
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tacker Mentor

tacker

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Posted

try this cut and paste

http://store.summitracing.com/partdetail.a...mp;autoview=sku

they are not for high pressure system so would have to be installed into the return line where there is no pressure well not much at least.

Russco Proficient

Russco

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Posted

I got one of the Moroso cool cans & they work - just got to keep packing them with ice. Unfortunately had to remove for defect notice, if you want it for a good price pm me. Picked-up 22rwhp on the dyno back to back with & without using this cooler. I plumbed mine in between the low pressure lift pump and the surge tank.

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