3.2L Engine Rebuild Advice

[Gordo2]

Folks,

I finally purchased a 3.2L engine with the intent to rebuild over the winter and put into my SC. I have always wanted to build a solid engine that provides a considerable increase in performance (street driven, but want to DE in the future).

The engine I purchased was rebuilt by the previous owner around 30k miles ago back in '02 and the car sat garaged since '06. The guy seemed technically knowledgeable/capable (he towed the car to my house in a F-350 that he rebuilt from a wreck and converted it to run on veggie - pretty cool). The guy provided all receipts dating back to the original owner. Some of the highlights of the engine rebuild included new Mahle P&C's (9.5:1 CR from what I can tell), new valve guides. Also has a new distributor and DME box. Machine work was primarily clean up.

The engine currently runs rough, which I'm trying to sort out (I'm new to Motronic). When I've had it running, it revs strong up to red line with no signs of knocking or oil burning.

What would you do with an engine like this? Tear it down to ensure it spec's out, seal it up and drive it?

Also what would you recommend for performance increases - I'm considering getting the cams reground (not sure what spec I should go with). Backdated exhaust to SSI is an obvious. I'm also considering dumping the motronic for PMO's and Electromotive XDI.

Appreciate any thoughts on how you might proceed.

Thanks, Gordo

[alniki]

Probably only needs some good fuel injectors, injectors seem to clog after sitting for years. My own experience: bad injectors cause rough idle but the effect is not so obvious at high rpm though you can easily feel the power increase after cleaning or replacing them.

[E Sully]

Do you have any idea of the total mileage on the engine? How much of the engine was rebuilt? It sounds like the top end was completely done, any idea what shape the crank and rod bearings are in? I would do a leak down and compression test, make sure the speed and reference sensors are set to the right clearance. As stated above, sometimes an injector sticks and a tap with a screwdriver handle will free it up. I had two that were sticking. I put 12 volts to them one at a time and felt them for a click that indicated they were working. Standard things like what shape are the plugs in will give you an idea if the cylinder is firing correctly. How are the wires, distributor, and wires.
As for performance, someone more knowledgeable will have to give you tips on that. I know that backdating the exhaust and a Steve Wong chip are the quickest ways to a horsepower boost, but others will have to give you info beyond that. A lot depends on your budget. I also recommend you upgrade the suspension, horsepower without control isn't of much use.

[Gordo2]

Good point on getting compression/leak down (assuming I get it running right). That should give me a good indication if there is any reason to break it down.

Engine had around 185k miles on it when it was rebuilt. It was a full up engine rebuild (top and bottom ends). The machine shop receipt shows the crankshaft was magnfluxed, polished and "parco-lubrited" - had to look that one up; apparently some sort of surface coating to help reduce friction. Doesn't show any cost associated with resizing journals (which is good).

The engine will be going into my SC, which I just finished a full up suspension refresh with many upgrades.

Will look to the injectors once I check the other basics.

Thanks, Gordo