Changing Pistons an a 2000 GTS

[GTSGUY]

I'm having my stock heads ported and will also be changing the cam. I will be going with a Paxton supercharger soon and I have the following question. While the heads are removed, if I remove the oil pan, I presume I can change the pistons without removing the crackshaft??? I would like comments from people that did it. Is this easy to do??

Thanks

 

[Fatboy 18]

Yep your right you can change the pistons with the Heads off, Pan dropped, and engine still in the car I know Viper Baz uk has done it, He also had a whole bunch of pics somewhere? Drop him a pm and I'm sure he will post up the link

Mark

 

[EllowViper]

Short answer...Yes...very very easy to do. Under a $2000.00 job for the parts/labor.

 

[Chuck 98 RT/10]

Seems like an awful lot a work to cut corners. If I were going to all that expense I'd go the whole nine yards and pull the block for balance and blueprinting.

 

[1BADGTS]

WAIT ,what about the rebalence of the rotat assembly -new piston weights ect.

 

[BOTTLEFED]

Diamond pistons are direct replacements for the stock cast pistons and require no balancing.

Chuck, I don't get your logic. That's like saying," My wife and I need some couples counseling, but that is just cutting corners, so I'm just going to fix it for good and give her a lobotomy so we don't have to go through counseling again."

 

[plumcrazy]

I don't like this idea at all. I know baz did it with good results but I'd be too afraid of the balance being off.

Do it once and do it right. Trust me, its not fun trying to cut corners....

 

[1BADGTS]

I don't like this idea at all. I know baz did it with good results but I'd be too afraid of the balance being off.

Do it once and do it right. Trust me, its not fun trying to cut corners....

EXACTLY= break a Viper Motor down and rely on what should be a proper balence without checking =to each his own.

 

[2000_Black_RT10]

I would have taken the block out and honed the bores, clean up the block, skim the block or heads of needd, balance the assembly, replace crank seals, check gaps, journals, seat new rings, new bearings if needed, etc.. all of which would probably add up to an additional $500 and a bit more time.. at least it would have been done right. Seating the rings with a fresh hone would be on the top of my list especially since adding a supercharger, you may be asking about blow-by a few months from now. Why take the risk short cutting, it's an expensive engine.

 

[GTSGUY]

Thanks for your comments, the only reason to change the pistons is be safe, so if I do not balance the engine (BLUEPRINT) I should keep it as it is??

 

[plumcrazy]

doing pistons is better than not doing them i guess.

balanced/built right > swapped pistons > cast pistons

a boosted engine is going to be put under a lot more stress than a N/A engine. you "might" get away with it but for how long ? seating rings is pretty important especially on a boosted engine ,id think its gonna be a lot tougher just doing the piston swap.

id get a call into greg good asap, let the pro help you with this. he is tough to get on the phone sometimes but is worth the wait. see what he tells ya. maybe im wrong (usually i am)

gregs number is 713-290-1103

 

[Chuck 98 RT/10]

Chuck, I don't get your logic. That's like saying," My wife and I need some couples counseling, but that is just cutting corners, so I'm just going to fix it for good and give her a lobotomy so we don't have to go through counseling again."

But your wife is not your Viper. While you may enjoy sliding a piston into both, only one do you love, the other you'd prefer giving a lobotomy to.

 

[RTTTTed]

I'd never, ever change out pistons and rings without a hone. I'd also never consider changing pistons until after I had checked the bore for straightness,and had the bores honed (probably bored) so that the pistons fit.

Did you say that the engine had less than 3,000miles? Night be the stock size bore - but I wouldn't waste my time changing pistons unless I knew the bore and (ring edge cutting)hone were perfect.

Who makes a set of forged pistons to fit into the stock worn bore? I suspect that stock bore forged pistons could be available or was your plan to pull down the engine and then measure it and order custom piston sizes?

If you can afford a Viper you can afford to do it right. As mentioned in a couple posts I wouldn't expect a ring seal.

I re-ringed and bearinged an engine (400 B) with rags over the crankshaft during the hone ... but the engine cost was $100 for rings and bearings. It also only needed to last for 3 months. NOT a viper.

Don't do it!

Ted

 

[Joseph Dell]

If your new pistons+rods weigh the same as your old ones, then you don't need to remove the block for a full balance job. As for honing the cylinders, just get a ball-hone and create a nice cross-hatch for 20-30 seconds. your rings will re-seal with no problem. just don't scuff the crank when using the hone.

good luck!

 

[RTTTTed]

And don't forget that engines are rebuilt is 'clean' rooms and sealed in plastic to keep out dust. So if you leave any grinding material or filings from when you ground the cylinder walls that didn't get cleaned off of your inner block, cam area, lifters, crankshaft, ...

A spinning hone uses various cutting fluids/lubricants and throws 'mteallic grinding dirt' around the room and inside the engine.

Ted

 

[Chuck 98 RT/10]

Thanks for your comments, the only reason to change the pistons is be safe, so if I do not balance the engine (BLUEPRINT) I should keep it as it is??

If playing it safe is the reason you are swapping pistons then why are you cutting corners at all? Either keep the pistons stock and the boost reasonable or pull the motor and do it right. JMO.

 

[Camfab]

Who's doing the work?

 

[99 R/T 10]

But your wife is not your Viper. While you may enjoy sliding a piston into both, only one do you love, the other you'd prefer giving a lobotomy to.

 

[Joseph Dell]

And don't forget that engines are rebuilt is 'clean' rooms and sealed in plastic to keep out dust. So if you leave any grinding material or filings from when you ground the cylinder walls that didn't get cleaned off of your inner block, cam area, lifters, crankshaft, ...

A spinning hone uses various cutting fluids/lubricants and throws 'mteallic grinding dirt' around the room and inside the engine.

Ted

Partially true. Engines are rebuilt in garages all the time. Brake Cleaner is an engine builder's best friend. That and WD40. And if there is dust or other 'stuff' that is in your motor when you run it, it comes out in the oil filter, oil pan catch, etc... Put another way, rebuilding viper engines is NOT rocket science. Neither is rebuilding engines in general. One who has never tried it shouldn't be afraid to just b/c they are worried about dirt or dust.

 

[treesnake]

I would have taken the block out and honed the bores, clean up the block, skim the block or heads of needd, balance the assembly, replace crank seals, check gaps, journals, seat new rings, new bearings if needed, etc.. all of which would probably add up to an additional $500 and a bit more time.. at least it would have been done right. Seating the rings with a fresh hone would be on the top of my list especially since adding a supercharger, you may be asking about blow-by a few months from now. Why take the risk short cutting, it's an expensive engine.

Seems like an awful lot a work to cut corners. If I were going to all that expense I'd go the whole nine yards and pull the block for balance and blueprinting.

doing pistons is better than not doing them i guess.

balanced/built right > swapped pistons > cast pistons

a boosted engine is going to be put under a lot more stress than a N/A engine. you "might" get away with it but for how long ? seating rings is pretty important especially on a boosted engine ,id think its gonna be a lot tougher just doing the piston swap.

id get a call into greg good asap, let the pro help you with this. he is tough to get on the phone sometimes but is worth the wait. see what he tells ya. maybe im wrong (usually i am)

gregs number is 713-290-1103

If playing it safe is the reason you are swapping pistons then why are you cutting corners at all? Either keep the pistons stock and the boost reasonable or pull the motor and do it right. JMO.

The phrase, "save a dime, spend a dollar" comes to mind....

 

[EllowViper]

Well, I've got a hard 10K miles on my "cutting the corners" piston swap with no "noticeable" issues. Understood all said regarding this procedure and cheap-a$$ way of doing this. Believe me...I thought about that a lot. But I have been in many auto/outboard/2-stroke/snowmobile/etc engines and as JD said..not rocket science. Just need to know what to look for and what things typically are non-negotiable. Time will be the ultimate judge.
I did not use torque plate to hone. Just covered the crank and deglazed. Did not mic the cylinders to check for wear/out-of-round. Could still see the OEM cross hatch on all the cylinders with no scoring/abnormal indicators. No reason to believe cylinder wear to be an issue or bore to be out of OEM spec given visual review. Old pistons looked great. No scoring or abnormalities. Rod bearings looked fine as did the journals. No visible abnormalities.
File-fit rings fit perfectly out of the box. Replacement pistons .005 under stock bore size. Gram wt of forged pistons within range of service manual variations of cast pistons. 443 grams I believe.
At any rate, would I have seen something during the teardown that would have lead me to believe the engine required additional prep or a complete tear-down, I would have done it. For what its worth, the Service manual has instructions for doing this very procedure regarding a basic piston replacement. They even have a method to change the rod and main bearings without dropping the crank...so a lot of in-vehicle engine work can be accomplished before a complete tear-down is needed.
Like I said, time will be the ultimate judge.

 

[2001 GTS]

With my motor build I was heavily considering just swapping the pistons with the motor still in the car as well. But like all the other knuckle-heads are saying...why not just do it right the first time so there won't be any what-ifs?

 

[plumcrazy]

it is hard to argue with a guy that has 10k miles on his engine....

 

[RTTTTed]

I'm sorry, In no way was I implying that engine rebuilding was rocket science. I was merely stating that although I have done an "in-frame" rebuild, it was with an expected much shorter lifespan.

I wasn't recommending a machine shop rebuild (I disagree with align boring and shaving new engine blocks that don't need it). I was trying to show that it is much simpler to removed the block and crank so that bore can be measured, cyliners can be properly hone and engine block can be properly cleaned after machine work. I would recommend spending a few hours and debur the block. I also recommend installing a swinging oil pan pickup while the engine is out.

I personally always pressure wash any machined surfaces before reassembly. This helps remove the burrs from the gouges made into the cylinder walls.

If you bought file fit rings and "they fit" your bore is too large or you got the wrong rings. File fit rings are made too big so that they can be custom fit for engine use (racing, street, etc.)and bore size. They're not supposed to 'fit'.

Ted

 

[01ACR/VIPER]

Partially true. Engines are rebuilt in garages all the time. Brake Cleaner is an engine builder's best friend. That and WD40. And if there is dust or other 'stuff' that is in your motor when you run it, it comes out in the oil filter, oil pan catch, etc... Put another way, rebuilding viper engines is NOT rocket science. Neither is rebuilding engines in general. One who has never tried it shouldn't be afraid to just b/c they are worried about dirt or dust.

AMEN to that.It`s just a motor.