what does an engine rebuild kit actually do?

DroopDaddy408 · Post by **DroopDaddy408** » Mon Jul 20, 2009 11:18 am

I've seen this kit on MPX http://www.modernperformance.com/index.php and was wondering what it actually does. I know that it replaces old worn out part with new ones. I know it can give you like another 150,000 miles but does it add hp? Does it bring it up to factory specs or stronger?? If anyone can help explain it that'd be koo. Thanx in adv. guys.

excon · Post by **excon** » Mon Jul 20, 2009 2:27 pm

the link you gave is just to MPx's website.

Rebuild kits are designed so that if you have worn out rings or bent rods that you can replace it with factory spec parts. However if you are planning an upgrade you can do it with forged internals.

Forged metal internals are cast from steel and then placed under extreme pressure and force so that all the air bubbles are out of the steel. Then more metal is applied to the forged piece and the process is repeated until there is no air in the piece. It is then brushed or "honed" for directional use.

You can see why forged internals are better than plain ol steel. They take more abuse and generally last longer.

So to answer your question, no it won't add power unless you're bumping up the compression. Just longevity.

DroopDaddy408 · Post by **DroopDaddy408** » Mon Jul 20, 2009 2:54 pm

Thanks Bro. That was helpful. It sounds like a pretty good idea to do since I'm at 105,000+ miles. If that is a bottom end build, what's a top end build?
sorry bout the link, I copied it from the actually page the kit was on and but it just sends it to the home page. tryed it several times, oh well.

excon · Post by **excon** » Mon Jul 20, 2009 7:27 pm

uhh... you don't need to rebuild unless something goes wrong. If you've got worn rings, cracked pistons, bent rods, etc then yes, (duh) rebuild. Otherwise, I wouldn't rebuild it with forged internals unless you want piece of mind (and have money to burn).

Adionik · Post by **Adionik** » Mon Jul 20, 2009 7:38 pm

If your compression is fine and your timing hardware is all new....don't even worry about it

DroopDaddy408 · Post by **DroopDaddy408** » Tue Jul 21, 2009 12:08 am

^ But it does add a grip of mileage to your car? So if I get close to the 200,000 mark it wouldnt be a bad idea rite?

darthroush · Post by **darthroush** » Tue Jul 21, 2009 1:29 am

No need if nothing is broken. One of the Golden Rules of Living: "If it isn't broken, don't fix it."

DroopDaddy408 · Post by **DroopDaddy408** » Tue Jul 21, 2009 12:09 pm

True dat, true dat. But I also know that you dont have to wait for shit to break to fix it. You gotta kinda figure out when your car is on its last days. My car runs good rite now so your advice works best for me just to chill. But It's always best to be in the know so you can plan ahead. Ya feel me

DaShukSXT23 · Post by **DaShukSXT23** » Thu Jul 23, 2009 12:54 am

The kit from Modern does offer several options for compression so in effect you might get a little fresher than stock, but for the money it's probably impractical unless there is something seriously wrong with your engine. However if you are going to throw something on your car to get un-godly amounts of hp, it would probably be a good idea.

They no longer offer the top end rebuild kit for the 2gn on MPx, I believe because they used the Crane camshafts in them and Crane is no more. It was a good kit before because I believe they gave you an upgrade camshaft over stock and if you had minor bolt-ons like intake, exhaust, etc. it made a bit of a difference.

Post by **occasional demons** » Thu Jul 23, 2009 9:43 am

DroopDaddy408 wrote:^ But it does add a grip of mileage to your car? So if I get close to the 200,000 mark it wouldnt be a bad idea rite?

The factory internals should hit that with proper maintenance. The only thing that may not, would be the valve guides. I have over 140,000 and replaced the exhaust giudes at 112,000. But then that could be considered maintenance. It still runs strong, and I really don't see it not hitting 200,000 at this point.

If it was boosted that may be another matter.

Post by **racer12306** » Thu Jul 23, 2009 9:49 am

There is no doubt in my mind that with proper maintenance (<- that is the key) that every car on the road can last to 200,000 miles.

Proper maintenance varies from car to car.

darthroush · Post by **darthroush** » Thu Jul 23, 2009 12:17 pm

DroopDaddy408 wrote:True dat, true dat. But I also know that you dont have to wait for shit to break to fix it. You gotta kinda figure out when your car is on its last days. My car runs good rite now so your advice works best for me just to chill. But It's always best to be in the know so you can plan ahead. Ya feel me

I feel ya. Just saying, that generally things start to go wrong before the engine completely goes. Once you start losing oil, burning oil, etc., then I'd start looking into it. Just my thoughts on the matter anyways.

racer12306 wrote:There is no doubt in my mind that with proper maintenance (<- that is the key) that every car on the road can last to 200,000 miles.

Mhm. My 5.8L '86 F150 is almost to 200,000 and still going strong . Quite contrary to the belief that American V8 engines don't last long at all. It doesn't go through any oil really or anything. My Neon is now almost to 91K. Everything is A-OK on it. Though, some of the people down the road seem to think I work on my cars too much by changing the oil regularly on them.

esfan · Post by **esfan** » Thu Jul 23, 2009 7:44 pm

you don't wanna rebuild your engine if your engine is still running...

proper maintaining will keep it good. adding oil and check somewhere else is always cheaper than rebuild the whole thing. if it's not a rod breaking or piston things or something internal cause the engine dying, i don't see any purposes for rebuilding the engine.

Perfctsouljah · Post by **Perfctsouljah** » Wed Jul 29, 2009 5:15 pm

DroopDaddy408 wrote:True dat, true dat. But I also know that you dont have to wait for shit to break to fix it. You gotta kinda figure out when your car is on its last days. My car runs good rite now so your advice works best for me just to chill. But It's always best to be in the know so you can plan ahead. Ya feel me

That is for sure brother.

If you do all of the work for a rebuild yourself, a proper rebuild will cost you somewhere in the 2k range. A proper rebuild includes having the block, and head sent to a machine shop to have them cleaned, machined, and checked for deformities and imperfections(not cheap

). So if you have someone else rebuild your motor for you, it is going to add a ton of cost to your rebuild. Typical shops charge anywhere between 80-85 dollars per hour on labor. I believe typical Flat Rate hours on a rebuild run around 13 FRH. So you now have an additional 1100 added to your cost. And this is for a stock rebuild. If your going above and beyond stock with previously mentioned forged pistons, etc... as far as your cost is concerned, the sky is the limit.

Until your motor craps out, just take some of your cheddar thats burning a hole in your pocket and shove it into a savings account. Let your car pay you back through all of the mileage you can squeeze out of it. It may cost you to repair a few things, but it's not as expensive as some options. IMHO

Hope that helps.

OhNo2.0 · Post by **OhNo2.0** » Wed Aug 05, 2009 5:05 pm

I've got a spare 2.0 sitting in the shop waiting to replace the motor that is currently in my car, the girl who owned this car before obviously didn't know what oil was and the last oil change was about 25000km before and the oil WAS NOT even on the dipstick.

So it needs to be replaced, it sounds like shit and I guarantee the bearings are all shot.

And just because the spare motor actually had oil in it, doesn't mean I'm just going to throw it in my car without rebuilding it. I found a supplier who supplies a whole kit for ~$350

That includes oil pump, water pump, timing belt, pulley, tensioner, pistons, rings, pins, rods, gaskets you name it. I'd be stupid NOT to rebuild it. And as my general rule, if it has over 250,000 or even 200,000 it's due for a rebuild. And if it's being swapped, rebuild it anyways unless it's under 75,000

Perfctsouljah · Post by **Perfctsouljah** » Wed Aug 05, 2009 9:52 pm

OhNo2.0 wrote:I've got a spare 2.0 sitting in the shop waiting to replace the motor that is currently in my car, the girl who owned this car before obviously didn't know what oil was and the last oil change was about 25000km before and the oil WAS NOT even on the dipstick.

So it needs to be replaced, it sounds like shit and I guarantee the bearings are all shot.

And just because the spare motor actually had oil in it, doesn't mean I'm just going to throw it in my car without rebuilding it. I found a supplier who supplies a whole kit for ~$350

That includes oil pump, water pump, timing belt, pulley, tensioner, pistons, rings, pins, rods, gaskets you name it. I'd be stupid NOT to rebuild it. And as my general rule, if it has over 250,000 or even 200,000 it's due for a rebuild. And if it's being swapped, rebuild it anyways unless it's under 75,000

I would like to know what supplier you found the rebuild kit from.

You have a good point with your general rule for rebuild 250k or 200k, it is a good mileage to rebuild your motor if your having problems with it, or intend on adding performance bolt-ons etc. Just remember "If it aint broke, dont fix it."

Hope your rebuild goes well. Let us know how it turns out for you!