1G Refreshening motor

[Maes]

Hello question for you motor builders, I am refreshening my 6 bolt motor and the plan was to change head gasket and timing components along with all gaskets and seals. I'm to the point where I have suggestions from friends that are saying I might as well changes the main and rod bearings and piston rings. Should I? Absolutely nothing wrong with the motor prior to the refresh. Motor has less than 60k on it. I am however going to be changing the valve stem seals to gsc vitons also.

 

[nwBryce89]

Do you have the block totally disassembled? If the bottom end is still together and you never had an issue with it and it has good compression I would leave it. You can pop the con rod caps off and just check the bearings just for piece of mind. What's your plans or goals for the car/engine.

 

[Maes]

No the bottom end is not disassembled. Goals are reliable 350 hp currently.

 

[curt-s]

No point in changing the head gasket if it has not been identified as a problem or is required to be changed as a result of another problem.
You can check connecting rod bearings for wear but depending on condition, swapping in new ones (not an easy feat without removing the block) likely will not solve any problems.
You also cannot change piston rings without fixing any cylinder bore out-of-roundness and rehoning properly. You need a proper bore and hatch to seat.
Do a compression and leakdown and check your oil condition for signs of bearing problems before you start replacing those
parts. As you say nothing is wrong, leave them alone..
If you are due for a timing component change, by all means.
Valve seals, sure if you want to, I guess. Just don't lose any of the keepers down an oil drain.
Lastly, "refreshening" is not a word

 

[Maes]

The motor is out of the car and disassembled except for the the crank rods and Pistons. Those are all still factory stock untouched. I had good compression and no issues with motor period. I have the chance to replace gaskets and seals since the motor is almost 26 years old. I've had the motor for 13 years and I've only put maybe 5k miles on it. But I'm wanting to make sure I take care of any loose ends that may pop up as I want to do it right one time. The car will not be raced after but will be dyno tuned. More of a fun weekend car. It used to be my daily 14 years ago. Current turbo is Evo 3 16g and plans are to pretty much max that turbo out. If that helps any. I have all supporting mods to go plenty farther. Also I would like to stay away from taking the motor to a machine shop so looks like the rings would be out of the question but what about the bearings?

 

[jakk220]

Might as well go with a gates timing belt and ARP head studs if your going to go through it all. Also do not use a MLS head gasket unless you get the block decked and the head milled both to the proper RA specs for the gasket. Made that mistake already.

 

[Maes]

Thanks jakk220 that is already in the works. My main question thought is more so about the bearings and rings.

 

[jakk220]

Well since you don't want to take it to a machine shop I wouldn't bother if it's just the bearings you plan on doing. Especially if it only has under 60k on it. Me personally if I'm doing anything in the bottom end, I'm doing it all while it is apart.

 

[Maes]

Well since you don't want to take it to a machine shop I wouldn't bother if it's just the bearings you plan on doing. Especially if it only has under 60k on it. Me personally if I'm doing anything in the bottom end, I'm doing it all while it is apart.

Could you elaborate? The block is on an engine stand.

 

[jakk220]

Well assuming the bottom end is still stock I would be putting in forged internals, eliminating the balance shaft, new bearings, getting the block hot tanked and making sure the crank is all good, line hone....all that good stuff. I like going over the top with things so that I know when I want more power the engine is ready for it internal wise

 

[jakk220]

If you mean the main reason I wouldn't do the bearings its kind of the "if it ain't broke don't fix it" kind of logic for me. There is no real mechanical opinion I guess.... just preference.

 

[300dollarGSX]

If you decide to disassemble the bottom end further, I would suggest taking it to a machine shop, anyway. It wouldn't cost much for them to clean and inspect everything. They can check bore round and taper (unless you have the tools). Likely, with so few miles, you could just get or do a simple hone and replace the rings. They can install new core/freeze plugs and check the deck surface for flatness. If you plan to install everything yourself, I would recommend at least getting some measuring tools for the bearing installation.

 

[Maes]

So pretty much I shouldn't touch it right now. I do not have the tools required to check tolerances. I could purchase them if needed though.

 

[curt-s]

If you plan on doing only one engine, purchasing the tools does not make financial sense. A proper set of inner and outer micrometers to handle all the sizes you need would cost a lot of money. Harbor Freight (for yous down in the USA) need not apply here. For one or two shot deals, best off just getting a shop to do it while they are doing other things. You will need to get them to check crank balance among other things anyway if you are that serious.

 

[Maes]

I've decided not to touch the bottom end then. Thanks guys.