@Holmes
Well-known member
If you have a J code I’m sure you have wondered about its stock performance. Here are my results. The variables that may effect your results are: this is a 68 convertible (so its heavier than a coupe) and my fat butt - 240 lbs - skew the results you can get with a GT/CS; 4spd and rear are stock original and have never been rebuilt; tires are Cooper Cobra 215/70/R14; engine is bored .30 over and not decked but thin gaskets were used, heads intake and exhaust are OEM not CNC machined or ported - no aftermarket parts except for the valve train (valves and springs are OEM spec) cam is a Edelbrock 2122and rockers are 1.6 CompCam roll trip rail CCA-1431-16; orig Autolight 4300 (voted as Fords worst carb ever!) rebuilt by Pony Carbs NM rated at 440 cfm - see my gallery (with an Autolight 4100 1.18 this would be a 14 sec car easy); distributor OEM, balanced by Distributor Dynamics Ca; Motive Industries duel exhaust - H pipe with transverse muffler and turn downs.
I finally ran the motor in my avatar Wednesday, has over a 1,000 miles now and I have been babying it to long. Made 9 passes trying to adjust the distributor (ping) and the secondaries (bog) on the 4300. I had always set the secondaries on the 5th bump as recommended but found best performance on the 7th. It was very difficult to launch due to the stock 3.0 open rear and thin 25.3inch tires - I smoked the tries on the start 4 times. Crossed the line in 3rd gear around 4800 + rpm. 5 passes were in the upper 15 sec range with the best pass at 15.586 / 89.321. This is a good 2-3 seconds faster than a stock 289. Tires chirped in 2nd and 3rd gear. This 302really is a hell of a block. I stomped on it hard - no wonder it's a favorite.
Copier drum is bad so here are the numbers:
React .637 (this is bad; best .032 but I was trying to get traction)
I1 2.358
I2 6.578
I3 10.051
MPH 70.532
E.T. 15.586
MPH 89.321
The only published editor results I can find to compare is the 1968 Mustang (MT) 390ci/335hp, 3spd manual, 3.25, 0-60 - 7.8, 1/4 mile - 15.20 @ 94mph (which is silly - a 3spd for a 390?) Does anyone have a publication that recorded 1/4 times for the 68 J code Mustang? Anyway I think this is close if not a little better than published factory performance. However, that 230 HP rating is way off. A different method was used back then but people still throw 230 around. According to the calculator at the above trap speed a stock 302 only produces about 177 actual HP. This will be the starting point for my WOLF in SHEEPS Clothing.
NEXT MONTH: I'm installing port machined OEM intake heads and exhaust for comparison.
I finally ran the motor in my avatar Wednesday, has over a 1,000 miles now and I have been babying it to long. Made 9 passes trying to adjust the distributor (ping) and the secondaries (bog) on the 4300. I had always set the secondaries on the 5th bump as recommended but found best performance on the 7th. It was very difficult to launch due to the stock 3.0 open rear and thin 25.3inch tires - I smoked the tries on the start 4 times. Crossed the line in 3rd gear around 4800 + rpm. 5 passes were in the upper 15 sec range with the best pass at 15.586 / 89.321. This is a good 2-3 seconds faster than a stock 289. Tires chirped in 2nd and 3rd gear. This 302really is a hell of a block. I stomped on it hard - no wonder it's a favorite.
Copier drum is bad so here are the numbers:
React .637 (this is bad; best .032 but I was trying to get traction)
I1 2.358
I2 6.578
I3 10.051
MPH 70.532
E.T. 15.586
MPH 89.321
The only published editor results I can find to compare is the 1968 Mustang (MT) 390ci/335hp, 3spd manual, 3.25, 0-60 - 7.8, 1/4 mile - 15.20 @ 94mph (which is silly - a 3spd for a 390?) Does anyone have a publication that recorded 1/4 times for the 68 J code Mustang? Anyway I think this is close if not a little better than published factory performance. However, that 230 HP rating is way off. A different method was used back then but people still throw 230 around. According to the calculator at the above trap speed a stock 302 only produces about 177 actual HP. This will be the starting point for my WOLF in SHEEPS Clothing.
NEXT MONTH: I'm installing port machined OEM intake heads and exhaust for comparison.