Dollar to Horsepower increase, is it worth the cost?

[srbaker]

After debating for almost two years to build or sell I am going to build. The V6 I obtained is out of a 1979 Mustang. I was able to drive the car prior to the drive train being pulled (I have motor, 5 speed, driveshaft and axle) The cars original mileage was a little over 67,000 km or roughly 42,000 miles. It did not exhibit any smoke, overheating or loss of power.
At the moment I am debating as to what degree of power increase I want to achieve versus dollars spent. I was able to obtain the Offy intake and Holley.
The question now is how much do I spend on the motor ?
I have already obtained the full motor gasket kit, water pump, oil pump. The cam costs look reasonable so I am not adverse to changing that along with solid timing gears.
What I am facing now is "Do I do the heads (2.9L valve change) ? I was told the heads are currently in good shape (valves, springs, etc)
I was quoted $ 500.00 CDN for labor (crack check, cleaning, valve job, etc) plus parts to do the job of changing to 2.9L Valves. Unfortunately there is only one shop within normal driving distance and they have a wait time of six months or more.

So my question for the forum is "What is your guesstimate for HP based on the above without the valve work and then with the valve work? " I know there are other factors to consider but I want to know if it is worth the cost. Further if anyone knows of a shop in Eastern Ontario or even the GTA (Oshawa, Ajax, Toronto) I am not adverse to a drive.

The motor is rated at 109 hp stock, not a big jump from the Sunbeam motor. I drive a 2008 Chrysler Crossfire Roadster in the summer, not a speed demon but it goes pretty good. I would rather do whatever I am going to do on the motor before dropping it in.

Thanks for your comments and advice.

 

[MikeH]

Kudos on scoring the 79 motor. That saves you the trouble of finding a Ranger or Bronco II motor to get other needed parts from. The 79 already has the rear sump oil pan. I don't know anything about the 5 speed that came in the 79 though.

 

[srbaker]

Kudos on scoring the 79 motor. That saves you the trouble of finding a Ranger or Bronco II motor to get other needed parts from. The 79 already has the rear sump oil pan. I don't know anything about the 5 speed that came in the 79 though.[/QUOTE

The car originally came with a 4 speed but was changed to a Ford Type 9 5 speed (out of a Merkur he said). It shifted fine when I drove it, cable operated clutch.
The clutch plate and disc were recently replaced, no scoring on flywheel or damage on ring gear. It seems to be in good shape overall.

 

[MikeH]

I was wondering about that. Everything I've found said only the SROD 4 speed (basically a 3 speed overdrive) was the only manual, although I did find some reference to a B/W T-4.

 

[Barry]

After debating for almost two years to build or sell I am going to build. The V6 I obtained is out of a 1979 Mustang. I was able to drive the car prior to the drive train being pulled (I have motor, 5 speed, driveshaft and axle) The cars original mileage was a little over 67,000 km or roughly 42,000 miles. It did not exhibit any smoke, overheating or loss of power.
At the moment I am debating as to what degree of power increase I want to achieve versus dollars spent. I was able to obtain the Offy intake and Holley.
The question now is how much do I spend on the motor ?
I have already obtained the full motor gasket kit, water pump, oil pump. The cam costs look reasonable so I am not adverse to changing that along with solid timing gears.
What I am facing now is "Do I do the heads (2.9L valve change) ? I was told the heads are currently in good shape (valves, springs, etc)
I was quoted $ 500.00 CDN for labor (crack check, cleaning, valve job, etc) plus parts to do the job of changing to 2.9L Valves. Unfortunately there is only one shop within normal driving distance and they have a wait time of six months or more.

So my question for the forum is "What is your guesstimate for HP based on the above without the valve work and then with the valve work? " I know there are other factors to consider but I want to know if it is worth the cost. Further if anyone knows of a shop in Eastern Ontario or even the GTA (Oshawa, Ajax, Toronto) I am not adverse to a drive.

The motor is rated at 109 hp stock, not a big jump from the Sunbeam motor. I drive a 2008 Chrysler Crossfire Roadster in the summer, not a speed demon but it goes pretty good. I would rather do whatever I am going to do on the motor before dropping it in.

Thanks for your comments and advice.

srbaker,

The real benefit to the 2.8 swap is the big increase in mid-range torque.

Don't think you will get much benefit from the 2.9 valves unless you also seriously port the heads, port match the Offy intake manifold and change to a fairly 'hot" cam.

A mild cam, mild porting, Offy manifold and Holley 390 carb will probably yield about 150 HP and make a very nice "performance driver". The 2.9 valves might add 10 HP.

JMO, YMMV.

 

[srbaker]

srbaker,

The real benefit to the 2.8 swap is the big increase in mid-range torque.

Don't think you will get much benefit from the 2.9 valves unless you also seriously port the heads, port match the Offy intake manifold and change to a fairly 'hot" cam.

A mild cam, mild porting, Offy manifold and Holley 390 carb will probably yield about 150 HP and make a very nice "performance driver". The 2.9 valves might add 10 HP.

JMO, YMMV.

Thanks very much for your reply. That's the information I was looking for. I want something I can drive everyday if I choose without worrying about reliability. But I also wanted something with a little bit of "umph" if I drop the clutch and downshift.