Re-Ringing pistons Questions

[Onefast99gsx]

Hey guys- time to start thinking about '07. As some of you know the last time i went out to the track i spewed oil all over the motor due the dip stick popping out. It happened 2 more times after that, even with a new dipstick. Compression is lower than what most people report what theirs is. I'm low to mid 140 lbs. Motor has about 95k on it. Up until i parked it for the winter, i jury rigged it by clamping the dipstick in the tube. I hate the fact that it's cobbled up. I vowed not to race it next summer unless i fix the excessive blow by issue.

So, I talked to a machine shop locally and there is a guy that will assist me. I want to re-ring the pistons with the block in the car and crank untouched. The plan is to seal up the crank during the process. I mostly only need him for ensuring a good cross-hatch pattern in the cylinders.

So as long as i'm in there, i figure I might as well replace the rod bearings. Then I was thinking that i might as well replace the rods as well with Eagles or something. So my questions are,

#1 which rod manufactures rods will work with the stock 2g pistons?

#2 if the rods are a matching set, can you put them in without balancing the engine? I would think so, but I wanted to ask anyway.

Thanks much for any helpful advice.

[niterydr]

I would recommend to still balance the system. Most aftermarket rods are within a few grams of each other, but sometimes the weight is shifted.
We recommend and use King or ACL bearings in all of the motors we build.
None of the aftermarket rods will work with stock 2g piston. The stock 2g piston is a press-fit, setup, the aftermarket rods are floating pin...
I'd say just pull the motor and rebuild it with all forged units and save yourself the hassle.

[JET]

Yeah, if you are pulling the head off then yanking the engine isn't all that much more work. The machining will be better because it goes in the shop.

140 isn't that terrible, either just re-ring it or pull the engine out and do it right. Be sure to do valve guide seals while you are at it, they may be a big part of your problem. With only 95k miles, it is odd that you would get ring blowby.

[Onefast99gsx]

Thanks JET & Niterydr- I want to avoid as much as possible, pulling the motor. Unless you mean pull it, but leave the crank and everything else in tact. Because if the cranks gotta come out, then i might as well do a complete engine rebuild and I don't want to go down that road until it's mandatory (6 bolt swap)... I just rebuilt the head last summer ('05) with all new valve seals and was extremely careful when putting them in not to damage them. I understand you that no aftermarket rods will work with the stock OEM pistons. I don't mind just doing all the work just to change out the rings & rod bearings with new. I have time but doing a rebuild is something I just can't afford at the moment due to house hunting. I would expect that aftermarket rods, pistons, bearings and a complete engine rebuild would be at least $1500+.

So i guess I'll just stick to re-ringing the OEM pistons, hone it and put some new rod bearings in. I guess as long as the head is off, i might as well put some new valve seals in just for the sake of, it's off anyway. Maybe in 2008, i'll look at a 6 bolt swap but I just can't do it right now so that's why I opted for this route for now.

Thanks.

[carltalon]

If the cars still running and has 140 + across the board Id recomend leaving it and saving your money for a built 6 bolt. your better off doing it right the first time. A reringing will get you by for now till next year when you want to throw A gt35 + on it and you blow your rods. Just my 2 cents, All I know is a properly built Eagle/weisco 6 bolt can take alot of abuse.

[Enes]

Sorry to jump in this thread but its similar to my situation, last time i checked my compression it was still 170 to 174 on all cyl. but i was still geting blow by.
would hate to rebuild the engine if its just the valve seals wouldn't amount of blowby affect compression? if you had more blowby = lower compression..

where i'm getting at is if you do your valve seals wouldn't that increase your compression a bit too?

[Goat Blower]

Sorry to jump in this thread but its similar to my situation, last time i checked my compression it was still 170 to 174 on all cyl. but i was still geting blow by.
would hate to rebuild the engine if its just the valve seals wouldn't amount of blowby affect compression? if you had more blowby = lower compression..

where i'm getting at is if you do your valve seals wouldn't that increase your compression a bit too?


No. Compression is the highest amount of pressure at TDC on the compression stroke with all valves closed. Blowby going by the valve seals occurs when the intake or exhaust valves are open so it doesn't affect your compression.

You can replace your valve seals without taking your head off, but it's a tedious procdure. It involves having that particular cylinder piston at TDC and putting rope in the cylinder to keep the valves closed or pressurizing the cylinder with air to keep the valves closed and popping the spring retainers with a O2 sensor socket. It's probably best to just take the head off and replace your timing belt components while you're in there though.

[Pushit2.0]

I would say try a leak down test to see where the pressure is going, also check your PCV valve if that is bad boost pressure from you intake manifold could go to your crank case.

~John

[Onefast99gsx]

Yep, I'm gonna do a leakdown test. I have borrowed one from a garage. I just need to get a decent air compressor. Btw- my PCV was replaced with just a straight thru fitting. Both fittings on the valve cover goto a JAZ catch can. I took the hoses off the catch can and i could blow into each one of them without any restrictions. I know it works because i drain the JAZ catch.

Thanks.

[sleepydsm]

On my old car I honed the block in the car, re-ringed the cylinders, and replaced one piston. I used motor oil for lube on the cylinder walls while honing, taped off the coolant and oil passages, then scrubbed the heck out of the cylinders with warm soapy water to get any abrasives out. Re-ringin was easy, just make sure you put the ring gaps in the proper spots. Definately put a rubber hose or something over the rod studs so u dont scrape the journals.