Recently, my MGB GT V8 received a fresh(er) engine to replace the original engine that had, to my knowledge, never been rebuilt.
The 'new' engine is a rebuilt Land Rover Disco engine, a 3.5.
It has increased compression (9:1), flowed heads, EFI cam, Edelbrock 1403 on JWR manifold, new distributor with RPI ARP Amplifier, ARP mains studs and a Cloyes roller timing chain set. The engine has about 10.000 miles on it, so should be nicely run in.
Rolling road results: 186hp at 4800 rpm (flywheel, 143 at the wheels) when the carb and timing were tweaked at Airey Tuning. (all of this was done by the previous owner of the engine, who also built it)
I noticed during my first drive that, below 3.5k rpm, some torque seems to have been lost, in fact it feels rather anaemic. The fact that the difference in torque in such a relatively light car is so noticeable, makes me somewhat unhappy to be honest.
Above 3.5k rpm however, there is quite a bit more power than before. (but it's not a track car)
Generally, the engine runs very very smoothly except when I floor the throttle, at which point the car seems to develop a 'hickup'.
Now, there are several ways to fix this, and I'd like to have some of your input on what the wisest approach would be:
- Replace Edelbrock carb, intake etc and refit factory twin SU HS6 setup - with the appropriate needle
Fiddle with Edelbrock jets etc (to be honest, I'm not quite sure this is going to improve as the car was set up at Airey Tuning, which has quite a good reputation)
Increase acceleration pump action (either by replacing it or by increasing its duration)
Some other bright solution I haven't thought of