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/wwwthreads_images/icons/tongue.gif Last summer Jeepchick and I took our big trailer to Iowa behind the GM 4X4. What I learned was that if you are marginal on HP, then HAVE THE GEARS. Our Small Block 350 Chev-Lay was kind of short on HP for a job like we were doing, but we had the ability to tailor the gearing to take maximum advantage of every one of those ponies. By twin-sticking the NP205 transfer case, we had progressive 2WD ratios which were as follows: 12.84, 7.02, 6.55, 3.58, 3.08, 1.96, 1.57, 1.00 You can see that the top FIVE gears are perfectly spaced. 2nd Direct @ 3.58, 3rd Under @ 3.08 then 4th Under @ 1.96 then 3rd Direct @ 1.57 then 4th Direct @ 1.00!!! We could put that Shiv-Lay EXACTLY where it needed to be RPM-wise, and avoid long periods of unnecessary winding because the next gear was too far up. Making the double shifts was NO PROBLEM since the Under-Direct split was 1.96 you DOUBLE the tach shifting down and HALVE the tach shifting up./wwwthreads_images/icons/smile.gif That 300 Six is SUCH a good mill that you would be crazy/wwwthreads_images/icons/crazy.gif to get away from it. How about a transfer case mod instead?/wwwthreads_images/icons/tongue.gif

CJDave
A moonguy-operated Jeep Skunkworks in the "Heartland".
 

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/wwwthreads_images/icons/tongue.gif Now that you have mentioned it.......the Achilles heel of the 300 Six IS THE WATER PUMP! We have used several of those engines in Industrial applications....they were the INDUSTRIAL model.....and when you use a HUGE fan on the engine, the water pump lives about 60 days at ten to twelve hours per day of tach time. The bearing in the pump is too small and the end thrust from a bigger-than-normal fan is too much for it. We FINALLY set up a fan mandrel and drove THAT from the crank pulley, and got the fan off the water pump./wwwthreads_images/icons/crazy.gif

CJDave
A moonguy-operated Jeep Skunkworks in the "Heartland".
 

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/wwwthreads_images/icons/tongue.gif In smog-crazy California we always swept out the corners to find ways to be "marginally legal" without giving away all of the peformance hard-bought through good engine building. Here is ONE thing that seemed to work well with our catalytic converter equipped rigs: Drain the "berries" out of that catalytic converter and run them through a series of sieves such that you end up with only the larger sizes. Then take a Shop-Vac and tape it to the exhaust pipe and start it up. The berries can then be re-introduced into the cat body by holding them close to the hole while the vacuum does it's work. Then use a bolt-in core plug to cap the hole in the catalytic converter. The "large berry only" pack will allow more open flow area, and seems to work just as well as the dense pack ever did. We always passed the smog tests with colors flying, wound tight in second direct./wwwthreads_images/icons/crazy.gif The performance enhancement came from a reduced exhaust restriction due to the simple fact that the TOTAL SKIN AREA of the berries over which the exhaust had to rub was reduced, and the square area of OPEN SPACE was increased. There is more open space in a room full of beach balls than there is in a room full of ping pong balls./wwwthreads_images/icons/crazy.gif

CJDave
A moonguy-operated Jeep Skunkworks in the "Heartland".
 
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