side project: 1988 Thunderbird Sport 5.0L

[Ford & Jeep Fan]

I've had this old car since 97. it has sat quite a bit in the last 15 years. planning a resurrection of sorts and with a possible entry into the Nevada silver state classic challenge in 2 years.

Car specs 1988 Thunderbird Sport 5.0L EFI (155HP stock) Sport means it has the same stiffer suspension as a 85 up Mustang GT and analog gauges.
AOD trans
2.73 8.8 rear Axle (currently has 3.73 gears)
I have most of the parts for this project
I have 90% of the engine parts needed to build a nice 325HP 5.0L (This a THIN Budget build )

My plan is convert the car to a carb as I'm just not wanting trust all the 37 year old electronics, plus they really would not like the changes to the engine. All i need for a carbed engine is valves, springs rockers and a intake. I have every thing else.

What are the Opinions/thoughts on this??

[UpstateCobraGuy]

I say go for it! You will need to lower the fuel pressure coming from the tank mounted fuel pump or change the whole to '85 Mustang GT (the last carbed Mustang). Why are you changing to 2.73 gears? Those are gas mileage gears, 3.73 are performance minded set.

Post photo too! :cool:

[J R Jones]

You state "possible" racing. Street and race are two different things. If racing success is an aspiration, the requirements are more demanding than street.
Start by researching the race, race category, and successful competitors. No sense taking a knife to a gun fight. IMO an 88 T-Bird Fox Platform is heavy, large, suspension compromised and not aerodynamic. All that would require compensation with horsepower.

I raced a 66 BP GT350 in Nationals and Trans Am against Corvettes. I was out-speced especially as Corvette models evolved and the GT350 did not. In current vintage racing there are guys running GT350s with engines much bigger and more powerful than I could run. They run mid-pack to Corvettes and Cameros to their dismay. A compromised basic package is hard to compensate.
jim

[Ford & Jeep Fan]

I say go for it! You will need to lower the fuel pressure coming from the tank mounted fuel pump or change the whole to '85 Mustang GT (the last carbed Mustang). Why are you changing to 2.73 gears? Those are gas mileage gears, 3.73 are performance minded set.

Post photo too! :cool:
It has sat long enough to for sure need a fuel pump and maybe a new tank. No problem as i even have a 20 gal fuel cell.
The gear change is because it has a AOD. at WOT they will not stay in OD and force a downshift into Drive, And i would not want it to. OD make heat in a trans. An AOD it locked in Drive. I put many miles on this car years ago when it had the 2.73 7.5 rear axle.
The low power 5.0L is misleading in this car. It would without fail pull 4500 RPM in drive. Remember a 88 T-Bird is quite Aero. So To keep the trans alive I'd rather run the 2.73 (I even have a set of 3.08 if needed) in this race I'm only planning on having fun Not really pushing to the limits. say 100MPH class target.
And the plan would be to drive it there,..and Back home (about 3800 miles round trip.)


You state "possible" racing. Street and race are two different things. If racing success is an aspiration, the requirements are more demanding than street.
Start by researching the race, race category, and successful competitors. No sense taking a knife to a gun fight. IMO an 88 T-Bird Fox Platform is heavy, large, suspension compromised and not aerodynamic. All that would require compensation with horsepower.
.........
jim
I stopped by the "Race" 9 ( https://www.sscc.us/ ) that they held about 3 weeks ago in nevada. I talked to a few of the racers. to see what this race is about. My plan is to enter at the 100MPH class. In this race the Driver picks a class like the 100mph class and you start from a stop and try to hit the finish line with a elapsed time Equal to a 100mph Aerage. This is somewhat comparable to 90 mile long bracket drag race. My car Would actually do fine even at the 155HP stock set up,....except currently it has 155K on the engine an trans. The reason I'm want to build a carbed engine is that this car's EFI is a speed density system and would NOT like mods. Plus I'm not really ready to trust 40 years old electronics for 90 miles at 4000 RPM.

Not aero ?? For 1988 I think they were quite good https://cdn.dealeraccelerate.com/primo/1/726/43584/1920x1440/1988-ford-thunderbird-turbo

[J R Jones]

FJF,
The 1988 Ford Thunderbird Sport, like other ninth-generation "Aero Birds" from 1983–1988, had a drag coefficient (\(C_{d}\)) of 0.35. This was a significant improvement over the 1980–1982 model, which had a \(C_{d}\) of 0.50.
That is about the same as the drag coefficient of the eleventh generation T-bird and other current street cars. The rest of the story is that the Cd is applied to the total frontal area. Bigger cars have more frontal area and more total drag. Spec racing does even the competition, like a rally does.
My buddy built a 1988 T-Bird Sport (manual trans) into a road racing track day car. In the third session at Road America (4.2 miles and three top speed opportunities per lap) the 1988 low performance block split lengthwise from the distributor to the back of the lifter galley. High RPM is stressful.
jim

[Ford & Jeep Fan]

FJF,
The 1988 Ford Thunderbird Sport, like other ninth-generation "Aero Birds" from 1983–1988, had a drag coefficient (\(C_{d}\)) of 0.35. This was a significant improvement over the 1980–1982 model, which had a \(C_{d}\) of 0.50.
That is about the same as the drag coefficient of the eleventh generation T-bird and other current street cars. The rest of the story is that the Cd is applied to the total frontal area. Bigger cars have more frontal area and more total drag. Spec racing does even the competition, like a rally does.
My buddy built a 1988 T-Bird Sport (manual trans) into a road racing track day car. In the third session at Road America (4.2 miles and three top speed opportunities per lap) the 1988 low performance block split lengthwise from the distributor to the back of the lifter galley. High RPM is stressful.
jim
Yes I am aware it not nearly as slippery as some of the cars built toady. (My 2016 fiesta is probably better) But is was good for its time an looks good.
There really are NO low performance Blocks in mid 88 all 302 blocks were the same by that time. A non HO and a HO were VERY different as far as parts go. THey went so far to use a different firing order.
My plan for the 2.73 or 3.08 gears are to keep revs at 100 at about 4K RPM. Combine that with the fact I'm going to build it to less than 10 to 1 compression it will live quite fine.

[J R Jones]

FJF,
My "low perf" block reference was just indicating it was not high performance, or Boss 302.
Watch Dave Tabor's coupe videos of the Nevada event. As he leaves the start line there is a fair amount of clutch slipping to accommodate his gear ratio. That would be a hassle on the street especially with a heavier car.
Swapping gear ratios for the duty cycle requires dedication. Racing on a National basis we set-up complete third members with: 3.50, 3.89, 4.11 and 4.56 to pull the various straights at specific RPM.
jim