1693 Cat - Pump tuning

Where ya located?

Montana.

Just ran across an old thread on ATHS claiming that the 425 versions had a different turbo as well. True or false?

Also claimed to have been available up to 525 HP in other applications - True?

Many checks to be made, different turbo, possibly different pistons and a different fuel pump camshaft, I have detuned marine engines by just the rack setting but getting more power is not always as simple as it looks.

I have done as much checking as can be done on the interweb, it looks to me like everything is the same betwixt the 325 and 425 except the JWAC and maybe the turbo.

I don't have a serial tag on my engine otherwise I would try to look it up on Cat parts.

I would like to find an old timer that knows these engines like the back of his hand that I could talk to to glean some information from him.

You could probably go up to around 400hp fairly safely with just the turbo and aftercooler but will also need higher revs to get hp meaning that unless you change gear ratios you won't gain anything on acceleration and will have to keep it buzzing to make use of the extra power. The downside is reduced reliability, unless you actually need the extra power and can find the correct parts to do it, leave the old girl as she is and enjoy the low down grunt from that lovely old twin cam engine.

Does Cat have an equivalent to the Cummins CPL, which is where you can look up all the parts for an engine's specific rating? If so, that will be the place to go to find out what you need, by comparing it to the CPL for your 325 rating

Cat have their rack setting charts and the different arrangements for different horsepower are listed in their parts books, unfortunately, you need the engine serial number, arrangement number and bill of material numbers which are on the engine ID plate to correctly identify it and compare with others to see what you need,

As far as I know only 1 serial #for a 1693 65B0000 but there are at less 3 # breaks that involve different parts one being a spacer plate engine. I only worked on a few but have worked on D-343 engines So far from a expert.
I'm of the same opinion as catsilver ,if its not broke leave it alone. I have seen more than a few engines burnt down by wantabe experts turning up the fuel. Anyway it's yore engine carry on.
Good luck
Bob

As far as I know only 1 serial #for a 1693 65B0000 but there are at less 3 # breaks that involve different parts one being a spacer plate engine. I only worked on a few but have worked on D-343 engines So far from a expert.
I'm of the same opinion as catsilver ,if its not broke leave it alone. I have seen more than a few engines burnt down by wantabe experts turning up the fuel. Anyway it's yore engine carry on.
Good luck
Bob