348 Check Your FPRs!

My FPR episode in this thread:

https://www.ferrarichat.com/forum/threads/mondial-t-engine-left-bank-running-rich.613291/#post-147476155

 

Something doesn't look right to me, but it could just be me. In the above, it shows a male to male adapter - 14x1.5mm to AN6. The fuel rail line connects to the 14mm side and the AN6 is screwed directly into the FPR?! That should not hold pressure. I would think you need an AN6 to 3/8 pipe fitting for the FPR (they come with those) and an AN6 coupling to join the adapter to the AN to pipe fitting. Yes?

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Take line in left hand to Earl's and the FPR. Get the right fitting.

 

you need something like this. I think it is inverted flare one one side AN on the other?


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Yeah thats toooo easy LOL

 

Okay stooges, let me tell what went down at Earls. I have been there 3 times this week because I like them. They have everything I need EXCEPT anything that has anything to do with metric cone fittings. In fact they rolled their eyes when they saw the OEM FPR. Can't help you, they said. Moreover several people a year come into their shop asking the same question, but they don't have a solution. No worries, I have a way around it. Otherwise they were really helpful with all the other AN (Army Navy standard) and NPT (National Pipe Thread standard) parts I needed.

At the new FPR, I screw in a NPT 3/8ths into AN6 fitting. From the OEM 14mm x 1.5mm cone fitting (blue hose from the front of the fuel rail) to the adapter to a AN6 - AN6 union to the FPR AN6 fitting. Fuel feed to FPR done.

Fuel return from FPR is easy. AN6 fitting at FPR to AN 6 black nylon mesh (or stainless if I like), about 30" long or so (haven't measured it precisely yet). Fuel line to AN6 - 12 x 1.5mm adapter in fuel pump.

I'll get everything mocked up and shoot a picture along with the total cost of this little venture.

 

Well, I can say that took quite a while sourcing all the right parts. Apparently AN to metric cone adapters are not as common in the US as one would hope. But, below is the final assembly of parts:

1. AN6 to 14mm metric cone adapter - this attaches to the short SS hose at the front of the fuel rail. This is actually shown inverted. It should be flipped around.
2. AN6 to AN6 coupling.
3. AN6 to 3/8 pipe adapter (comes with the FPR kit from Summit Racing and includes O-ring).
4. FPR from Summit Racing.
5. Fuel pressure gauge (comes with FPR kit). Replaces brass plug in FPR.
6. 3/8 pipe plug with O-ring (Earls calls it a 9/16th plug b/c that's the wrench size). Attaches to outlet on side of FPR.
7. Same as Item 3. Fits to fuel return from FPR.
8. AN 6 straight hose fitting.
9. AN 6 90 degree hose fitting.
10. AN6 to 12mm x 1.5mm pipe (plus aluminum crush washer) into the fuel pump return.
11. Either nylon mesh or stainless steel fuel hose located between Items 8 and 9.

Since stock fuel hoses are black rubber, you could use the nylon mesh so long as the line is shielded (which it is underneath the car). Now all I need to do is run the gas tank out of fuel. I will install both sides and then get back to you. Everything came from Earls and Summit except Item 1. It took 3 weeks to arrive from NY somewhere.


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Did you find out where you got the FPRs before you swapped them out for the other system? Might need to replace mine, threaded type, and not liking the prices from anybody at the moment and struggling to track down where else they are used.

Many thanks
Adrian

 

rockauto.com has them. Part #PR298. I bought 2 a year ago....1 one them went bad after a month, but the other one is still good so maybe an anomoly with the one that went bad....don't know but they are cheap relatively speaking

 

Thank you; appreciated. Far far cheaper than advertised over here in the UK, even with shipping and import duties that will all get added.

 

Bump

Did anyone work out which ECU version runs 3.0 bar and which is 3.8?

I have a later 1992 car, after the swap to 3.8 but looks like I have the 3.0 bar fpr. Having some idle problems during cold start so trying to work out if the fuel pressure regulators is the issue.

 

It’s more of a yr thing . The 320 Hp eu spec or what ever stateside spec ? 316 Hp ?? Around 94 modal yr the last couple of yrs .
You can tell by looking @ the induction manifolds the later 3.8 bar have less strakes near the bulkhead.

 

Mine is just the regular garden variety TS 300hp but i read earlier the change is from 92 and engine number 27xxx???

 

3.0 Bar (137960) up to Engines:....USA 25013....EU 27843..........Thereafter: 3.8 Bar (147281)

 

what would happen if you just put the 3.8 bar fpr on a 3.0 car?

 

The ECUs will, based on the O2 sensors' signals, trim the fuelling down to still maintain the programmed AFR. This will happen when the ECUs operate in the "closed loop". However, there could be some problem during the engine warm-up while the ECUs operate in the "open loop" (not regulating the mixture based on the O2 sensors) as the mixture will be a bit too rich. Maybe this can be adjusted (made somewhat leaner) by adjusting the ECU trim potentiometers on the MAFs.