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By JBRob007
#83155
Having a hard time sorting out my 84 Auto Euro top end of 110 mph / 3800 rpms. It’s weird, my car has a four speed automatic and runs like a raped ape through the lower gears and up shifts just below redline as designed, but in 4th gear it appears to top out @ 110 mph & 3800 rpm as if it has a governor. The tranny isn’t slipping, no flaring, no rpm spiking, etc, it just stops gaining speed. We’ve replaced the fuel tank vent hoses, fuel strainer, pump, filter, etc, and it has GB’s fuel injectors so there shouldn’t be any kind of fuel restriction. New Sean Ratts engine wiring harness, top end refresh, serviced MAF & computers... Again, she starts & runs great just not reaching top end... not even close ☹️

Any suggestions on what to test or sort out next would be greatly appreciated.
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By worf
#83195
New fuel filter, right?

clogged cats/exhaust/muffler?
By JBRob007
#83207
New fuel filter. 36.5 exhaust manifolds with SS “Y” pipe to 3” SS pipe to 12” Magnaflow... nothing left to clog. I tell ya it’s weird ☹️
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By Stepson
#83302
Joel,
I had an 80 Euro S 5 speed (the Jalapeno) and it acted in a similar fashion. I determined that it was running out of fuel because the PO had fitted the incorrect fuel pump to the car. It started and Idled fine, but it ran out of fuel at speed.

Check your version of the fuel pump.

You could also have the distributor rotor fitted that is a spring loaded governor..?

Crushed or bent fuel could be a contributing factor.

What is your fuel pressure at the rails?
By JBRob007
#83404
Good question... I’ll check and check the fuel pump for correct part #. That should be easy enough. I have 7mm fuel hose on the fuel rails as opposed to 7.5 mm. I don’t think that would make a huge difference or create a restriction at speed... but, it might... Hmmmm.
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By worf
#83410
—^

It’s difficult to imagine a failure mode other than fuel mass flow or exhaust gas flow.
By JBRob007
#83604
It’s definitely not exhaust flow... if you’ve ever heard my Gold car... if anything it probably doesn’t have enough restriction / back pressure 👌👌👌. Guess I’ll recheck the fuel supply side of things - it’d be hilarious if the FP was off a 944 or some shit 🤫🤫🤫
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By worf
#83816
JBRob007 wrote: Wed Jun 02, 2021 10:09 pm It’s definitely not exhaust flow... if you’ve ever heard my Gold car... if anything it probably doesn’t have enough restriction / back pressure 👌👌👌. Guess I’ll recheck the fuel supply side of things - it’d be hilarious if the FP was off a 944 or some shit 🤫🤫🤫
84 Euro is LH. What size injectors?
By JBRob007
#83849
24 lb GB kit injectors.
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By Stepson
#84635
Joel, any update?
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By PorKen
#84655
What spark plugs are you using? Gap?

Are the ignition amps Bosch? (ROW 16V, in front of radiator)


Doesn't sound exactly like your problem but I had issues using non-resistor plugs with Hueco amps. Bad idle and would not rev over 3000.

https://rennlist.com/forums/928-forum/3 ... units.html
https://rennlist.com/forums/928-forum/3 ... mps-3.html
By JBRob007
#84662
Everyone: Thanks for the input. Life a.k.a. Work has been in the way lately (and finishing up on the Chiffon barn find) so I haven’t gotten to checking the fuel pump, etc... but I will. On the road for two more weeks ☹️

She revs to redline in the lower gears, but not in 4th gear, so not sure of any spark plug correlation. Purely a top end over 100 mph issue when she just stops going faster. Acceleration 0 to 60 to 100 mph is just fine...
By JBRob007
#84663
I’ll check on the plugs and resistors when I check the pump. Thanks!
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By checkmate1996
#84783
Did you put a new, trusted MAF in for a test?

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Panorama September 2021

great representation ~!