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Topic: 2.3 Turbo Crusing RPM Sweet Spot? (Read 1335 times) previous topic - next topic

2.3 Turbo Crusing RPM Sweet Spot?

Going on a few months now that enjoying my new to me 85 Turbo Coupe, 5-Speed stick, T-Bird. This one is a driver that purrs like a kitten and hums along at higher RPM s.  Open for consensus from group, Both opinion and fact ?
What is considered abuse, or what these 2.3 Four cylinder motors were designed for?
This is not as my daily driver and I like taking it out on a weekend morning when traffic is quiet and running the tach around the 4000 RPM range for extended intervals through the local twisted back roads.
(which feels to me on this motor, as what I'm calling the "sweet- spot" around 4K )
Over the years I've restored my share of muscle V-8s. This 4-cylinder stuff is new to me, so far I'm impressed.
Latest Find, 1985 FILA Style, 5 Spd. 4 Cyl. Turbo Coupe Thunderbird, Clean underside, Rough around the edges, well worthy of total restoration. A follow up to my 89 5.0 Mustang project.

Re: 2.3 Turbo Crusing RPM Sweet Spot?

Reply #1
Both nice cars!  Beautiful Bird.

I am not sure about the "happy spot" in RPM for that year since there were several changes after '87 that could change that.  Chuck and others will probably be the best go to for that information.

Is the car still stock or any changes been made to it?

1988 Thunderbird TC, 5spd
Stinger 3" single exhaust, Cone Filter, Adjustable Cam Pulley, Schneider roller cam, Walbro 255 lph, AEM Wideband O2
'93 Mustang Cobra replica wheels on 235/50R17

'21 F150 Powerboost
'17 Husqvarna TX300

Re: 2.3 Turbo Crusing RPM Sweet Spot?

Reply #2
I have to credit the previous owner on thorough job of rebuilding the 2.3 and adding an aftermarket inter-cooler. I don't know if it has any internal upgrades. The vehicle runs great but I'm sure it's not at it's full potential of more low end torque. Unfortunately it passed through another owner whom I suspect experimented with the vacuum & boost lines.  Again I'm educating myself on this and enjoy the challenge of sorting it out.
Latest Find, 1985 FILA Style, 5 Spd. 4 Cyl. Turbo Coupe Thunderbird, Clean underside, Rough around the edges, well worthy of total restoration. A follow up to my 89 5.0 Mustang project.

Re: 2.3 Turbo Crusing RPM Sweet Spot?

Reply #3
Very nice that is has the FMIC on it.

Are the rear brakes disc or drum?  '85 originally came with a 7.5" rear end with drums.  In '87 they went to a 8.8 rear with either 3.55 gears (manual transmission) or 3.75 gears (automatic).  Originally the '85 came with a T3 Turbo (not sure whether .48 AR or .63 AR). 

A larger than stock exhaust will allow the turbo to spool quicker.  I believe stock exhaust was around 2.25".
1988 Thunderbird TC, 5spd
Stinger 3" single exhaust, Cone Filter, Adjustable Cam Pulley, Schneider roller cam, Walbro 255 lph, AEM Wideband O2
'93 Mustang Cobra replica wheels on 235/50R17

'21 F150 Powerboost
'17 Husqvarna TX300

Re: 2.3 Turbo Crusing RPM Sweet Spot?

Reply #4
2.3T's sounds like an angry tractor, no matter what you do to them.  :toothless:

The "sweet" spot all depends on mods, etc.

For corner carving, 4K is probably fine. Not going to hurt anything. For highway cruising, I like to keep the rpms down under 3K (70 mph)
Long live the 4-eyes!  - '83 Tbird Turbo - '85 Marquis LTS - '86 LTD Wagon

Re: 2.3 Turbo Crusing RPM Sweet Spot?

Reply #5
Appreciate the input on engine speed.
This has drum rears. Exhaust is on the to do list, I'll explore the 3".
Latest Find, 1985 FILA Style, 5 Spd. 4 Cyl. Turbo Coupe Thunderbird, Clean underside, Rough around the edges, well worthy of total restoration. A follow up to my 89 5.0 Mustang project.