body parts , od, and engine modifications

ive got a 79 b in pretty good shape and ive also got a 69 in pretty rough shape , the doors on the 69 look great as well as the hood , so i figured id take the aluminium hood from the 69 and put it on the 79, which i figure should line
up pretty good but i was wondering about the doors, are the doors on bs interchangable or are they kinda picky ( meaning am i going to have to shim the hell out of the hinges or was the that much of a difference in the stamping at the factory) next question ive currently got a rebuilt od and gearbox which i planned on installing into the car once i got it painted , i was wondering is there any difference in the rear end or driveshaft on an od setup or should the rear end and driveshaft ive got in the car work?, last question i was trying to decide on which of the two engines to rebuild the 69 or the 79, where either of these more prone to broblems such as thinner casting and cracks or are the blocks and the heads basically the same? which one would be a better rebuild?

The body parts are interchangable. You can use the drive shaft and rearend . Ther is a difference in the OD drive shaft but yours will work. The 69 is a better engine. The engines after 75 had water choke heads that are bad to crack between #2 &#3. 69 also had free floating wrist pins and higher compression pistons. There was also a difference in the cams,but you can count on having to replace that in eather engine.

Since you are going for a racing application, use the 69 doors if you are concerned about weight; the 79 has extra metal inside the door, undoubtedly a safety feaature.

You said "69 also had free floating wrist pins and higher compression pistons"

When did they change???
What is the difference between the 69 and the 75Above, in compression???

I do not want to go crazy(More than I am...), but I want to build a better performance, durable engine. I want to do it to the 71 Engine, after 29years of service, both Harlan J., and I concur that there is little wear(To the cylinder walls)…

Should I go with "Off Center/Center" roller rockers, or would I just be wasting my money???
Is there a better push rod, for the MGB???

The last full year of the floating wrist pin was 70 there are some 71's out there with them. In 74 they went from 8.75/1 to 8.50/1. The rooler rocker with a fast road cam will give you a good improvement in lift. If you install it with the Rim flow wasted stem valves you will increase your CFM considerable. I used the crane pushrods in both my GT&Midget. They are lighter and stronger. Thats another bennifit of the roller rocker. They are lighter and stronger with less friction.

The last full year of the floating wrist pin was 70 there are some 71's out there with them. In 74 they went from 8.75/1 to 8.50/1. The rooler rocker with a fast road cam will give you a good improvement in lift. If you install it with the Rim flow wasted stem valves you will increase your CFM considerable. I used the crane pushrods in both my GT&Midget. They are lighter and stronger. Thats another bennifit of the roller rocker. They are lighter and stronger with less friction.

What is the difference between the "Off Center/Center" roller rockers???
Any suggestion which Vendor is a thumbs up and which is a thumbs down???

I am a believer in "Lessons Learned", what are the pitfalls, that I can avoid???

Are Crane "Push-Rods" hallow, do they expand as the engine warms-up???

Saw a good one on horsepower Tv last week, a rifle bored camshaft to lighten the cam for a small block chevy racing application. Bet that cost a few $. Then they threw on a composite (plastic) intake. Now there is some weight savings!

I'd worry about heat expansion on that cam at 8000 rpm in August on a racetrack.



Tim