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forged vs. stock 95 pistons

bp97tsi

Proven Member
79
0
Mar 27, 2002
Inman, South_Carolina
My 2 cents. Save up your money & go ahead & get forged ross pistons. Forged pistons can take a little more detonation abuse than the stockers. Say youre tuning & get a little detonation with the stock pistons. You could possibly melt a piston or blow a hole in one or 4. You got forged pistons & they can take more abuse & less likely to melt or burn, but it can be done. Think about it, youre about to spend some money on a rebuild. You know youre gonna be hot roddin this motor. Why not go ahead & spend a little more money to do it right the 1st time. :)
 

JET

Proven Member
223
0
May 20, 2002
Minneapolis
JE pistons are the ones that are giving forged pistons a bad name. They have a sidewall design that is very prone to piston slap when cold. Wiseco's and Ross' are much better. I am running 8.8:1 Wiseco's and love them. You cannot tell any difference from stock as far as noise goes. I also used Eagle rods. They are pretty cheap and hold 600 hp. You can get the combo for $800.
 

BryanK

Proven Member
133
0
Jun 25, 2002
Iowa
I've been told that JE's have a shorter piston skirt... is this what causes them to be more prone to slap? How sure are you that JE's are bad? No offense, I've just been told from an engine builder who uses JE's all the time that they're actually less prone to slapping.
Thanks,
BryanK
 

rdrkt

Proven Member
1,544
2
Apr 20, 2002
Baltimore, Maryland
Originally posted by BryanK
No offense, I've just been told from an engine builder who uses JE's all the time that they're actually less prone to slapping.
No intellegent 4g63 engine builder would agree with that. JEs suck if you dont want to hear the answer stop asking the question.
 

BryanK

Proven Member
133
0
Jun 25, 2002
Iowa
it wasn't a matter of not wanting to hear the answer, it was the fact that I don't know either the engine builder nor JET personally, so forgive my lack of trust. Thanks for the response though, you definately changed my mind about going with this particular builder (local guy=convenient). I'm just trying to weigh my options... unfortunately I don't have the $$ yet to actually go out and do anything, so I'm just trying to do as much research as possible until I do. Thanks for the help.
BryanK
 

rdrkt

Proven Member
1,544
2
Apr 20, 2002
Baltimore, Maryland
I keep forgetting that many of you guys werent around when people started getting hosed by JE with their motors. It sucked cost a lot of people a pretty penny. Which is why I am so adamant about it.
 

Tevenor

Supporting VIP
1,786
11
Mar 18, 2002
Rochester, New_York
The problem with JE's was simple. They recommend X for bore clearances. As it turns out, that was too small and many race and street motors seized as the piston swelled. When confronted, many of those same motor owners got told 'it couldn't be that, it had to have been bad machining'. So many engine builders had to rely on their own 'insticts' for clearancing which makes getting it just right a major pain in the a$$. Too tight and it might seize. Too loose and you piston slap.

Even though the quality of the piston itself is good, the lack of consistency is a major stumbling block. Hence why many DSM vendors will not build a JE based engine.
 

SOURCE1064

Proven Member
954
0
Apr 15, 2002
Paramus, New_Jersey
Originally posted by Tevenor
The problem with JE's was simple. They recommend X for bore clearances. As it turns out, that was too small and many race and street motors seized as the piston swelled. When confronted, many of those same motor owners got told 'it couldn't be that, it had to have been bad machining'. So many engine builders had to rely on their own 'insticts' for clearancing which makes getting it just right a major pain in the a$$. Too tight and it might seize. Too loose and you piston slap.

Even though the quality of the piston itself is good, the lack of consistency is a major stumbling block. Hence why many DSM vendors will not build a JE based engine.

That has me a bit worried now. I have JE 9:0.1 pistons that I'm going to have put in my car. My shop uses them on all sorts or rebuilds, turbo 911's, supercharged vettes, suv's, etc. I spoke with my mechanic and he said as many others that it all has to do with the machining process. I asked about piston slap and what not and he guaranteed that it will not occur because the machinist he uses is that good. Tevenor,or any other wiseman, when you said that the JE situation was a problem, do you mean now they have things set straight? Just a bit curious and nervous now after reading this.
 

UndergroundR32

Proven Member
664
0
Jun 6, 2002
NY
Don't go out and sell them just because you think that ROSS are going to be worth the trouble. This piston slap subject will be a never ending argument. It has A LOT to do with the machinist. Unless he does these installs on YOUR particular motor all the time with JE's and has never had one that slapped, then of course he isn't going to Garantee it. Talk to someone who has used him before for their 4G63 machining, and see how the motor is doing.
I know a few people by me with the same exact spec JE's you have, in their 4g63's, and they love them. One of them is an 11.5 second 1st gen eclipse. I hear little to no slap.
 

Tevenor

Supporting VIP
1,786
11
Mar 18, 2002
Rochester, New_York
Originally posted by UndergroundR32
Don't go out and sell them just because you think that ROSS are going to be worth the trouble. This piston slap subject will be a never ending argument. It has A LOT to do with the machinist. Unless he does these installs on YOUR particular motor all the time with JE's and has never had one that slapped, then of course he isn't going to Garantee it. Talk to someone who has used him before for their 4G63 machining, and see how the motor is doing.
I know a few people by me with the same exact spec JE's you have, in their 4g63's, and they love them. One of them is an 11.5 second 1st gen eclipse. I hear little to no slap.

I agree with this to some degree. If you have a machinist/engine builder that uses JE's all the time, and know what tolerances are needed to get them to not slap and not sieze, then go with it. The pistons themselves are good quality. It's the past history of swell that has made them undesirable in the past. If you are confident you can avoid this by having someone with JE experience build them, then by all means go to town. Just remember that building a nonturbo big block V8 is much different than building a 2.0 liter forced inducted 4 banger.
 

hose101772

Proven Member
290
0
Aug 15, 2002
murfreesboro, Tennessee
the harder you're going to run things the loser they need to be-how much depends on builder-i hope its ok for me to list a machine shop for everyone-they get blocks/cranks shipped to them from everywhere-so they can take care of you-MIKE'S SPEED SHOP-MURFREESBORO,TN. i let them do up my block-bored .020 over-.0045th is the tol. they machined in for j&e's-polished crank journals-mirror i tell ya-decked the block like a half thou-absolutely the most beautiful machine work you have ever seen-these guys are the best-balanced my rotating asm-no balance shafts-just as smooth as it ever was-i set the rings a little lose-had giant hp dreams-other than oil getting dirty by 3k miles-its perfect-over 10k miles on so far-from 100 degree days to well below freezing-solid as a rock-i'd recomend mike's to anyone as well j&e's/eagles.great folks-good products.

[Mod Edit: What is with the '-'? If you are going to continue to post in this forum, please use the '.' and the ','. They are located 3 lines down from the '-' in the same general area. ]
 

Slowboy

Proven Member
660
10
Jun 28, 2002
Sanford, Florida
We just built a JE motor, and have built JE motors for a few years. I have a JE motor with about 10k on it with no issues at all. Will they slap a little on a -10 degree morning? Yes, for about 10 seconds. Does it bother me? NAH.

The clearance JE suggest are off a bit from what they should be in our opinion, but not by much.

Picture is a block being honed for JE.

Regards,

Mike Huml
aka...slowboy
 

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OMN_DSM

Proven Member
334
0
Dec 13, 2001
Seattle_WA
So does anyone know what thier piston to wall clearance is or what they would reccomend? I was planning on having my engine machined to .005 clearance with Ross pistons, is this to tight? Thanks for your info!

Mike
 

DSM Performer

Probationary Member
18
0
Jun 4, 2002
Pawtucket_Rhode_Island
I have never had a problem with my JE's. I hod a set made for me about 2 years ago. 7.8:1's. You are right, their suggested clearences suck. My friends owns a Machine shop and he did the work for me. I've got 24K on my motor right now, and they are holding up just fine. I do get some slap in the mornings. But here in new england, it gets pretty damn cold. After the initial warm up, she sounds fine. Its not the pistons that have problems, its the specs they give you. If you can figure out the right clearences, then you should be all set. Like I said, I've hd no problems so far.
 

jayntguru

Proven Member
60
0
Jun 13, 2002
Acworth_GA
Perfectly happy Wiseco user here.

Check out my website, then the "history" page for a video of my car at idle. No torque plate, no piston slap.

If I had it to do over again, though, I would have just used big rods and 95+ pistons. If your goal is only ~ 500HP then those should hold up just fine. Much cheaper, and easier to get right.
 

KRAB

If you do build your engine with forged pistons how long will it last before it needs to be rebuilt? My sister totaled her 90 talon and I get the engine out of it so I thought here's a good chance to build it up. It will be my daily driver/street car so how will the forged internals do with all the miles that I will be putting on it?
 

BoostinAWD

Proven Member
813
1
Feb 14, 2002
Goodyear, Arizona
I just finished tearing my engine apart.

The bores are fine so I will just be honing and re-ringing.
I am sold on eagle rods. But I am not sure about pistons.
Now I know 95 pistons are press fit. So what would need to be done to get them to fit to the eagles?

I am keeping the standard bore. But am wondering what are the chances of running forged in a standard bore re-honed block? Not gonna happen or is it possible :confused:
 

GalantVR41062

Proven Member
204
1
Jun 7, 2002
Maple Grove, Minnesota
spec on stock pistons can be as much as .0035/ 35thousands, my Wiseco pistons recomend .0030, which I feel is to tight I will get them set to 40-45tousands with a torque plate I hope. But for J&E pistons I have heard .0035 seizing, and most people run .0060-.0070 with the Ross and J&E pistons. I would say 95pistons with around 500whp pending tuning, etc. I plan on going bigger after the 60trim so I know I wount use my built motor just yet.
 

GreenGVR4

Proven Member
97
0
Oct 13, 2002
Aurora_Colorado
I have 93+ Arias Pistons and 6-bolt rods, the machine shop just has to bore out the piston side of the rod slightly to fit the pin.
 

tanner261

Proven Member
82
0
Jan 4, 2003
Farmington Hills, Michigan
I'm running .020" over Ross pistons at .006" piston to wall. No piston slap on cold startup.

GreenGVR4: Is the machine shop using some sort of lock on the wristpin, or were the wristpins not meant for your rods (i.e. you have pins to fit 95+ rods)?
 

GreenGVR4

Proven Member
97
0
Oct 13, 2002
Aurora_Colorado
The pins were not meant for the rods, they are for the 7-bolt motor and mine are 6-bolt motor
 

GreenGVR4

Proven Member
97
0
Oct 13, 2002
Aurora_Colorado
The pins were not meant for the rods, they are for the 7-bolt motor and mine is 6-bolt motor
 

Rice Killer

Proven Member
34
0
Jul 11, 2002
Louisville, Colorado
Im running 8.3:1 Ross pistons, Eagle rods with a .055" piston to wall clearance. Absolutly no piston slap on cold starts. If the machine shop knows what there doing you shouldent have any piston slap.
Just make sure you know just as much as the machine shop or more when having them do the work so you can tell them what to do. That's what I did and everything turned out just like I wanted it to. :thumb:
 
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