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What pistons and what rods?

turbophein

Well-known member
i wanted to build my own bottom over the winter for minimal investment while focusing on the details that really matter.

i have never bought upgraded pistons or rods but have done stock rebuilds. after just looking on parts are fairly cheap.

i have spare 6 bolt virgin blocks, i can drop one off at a machine shop for inspection, etc.

eagle rods $289 i thought was pretty cheap. 6 bolt rods for 2 pistons. which is the setup i would like to do.

now for pistons i have no idea what i want. i found a few sets of forged pistons for under $400 and some Nippon racing Pistons for $175

add some bearings and machine shop time and i think $1000 total cost would be achievable.

curious to hear from you guys.

my goals are to have a strong built bottom end able to handle 500-600hp if i ever get there one day. 400hp reliably for 20k miles would be a dream come true i think.
 

slugsgomoo

Well-known member
I'm kind of with Coyotes on this, unless you're trying to bump compression and get a bit more low end...?

For "cheap" pistons, wiseco 1400HD? Not *that* cheap but regular wiseco seem to have skirt cracking issues and the 1400HD are bulletproof. I will caveat that with the fact that I ran a 2.0 with regular wisecos and it held up fine with an evo3 @ ~22psi (9:1 compression) for quite a long time before I sold it.
 

jeverts

Well-known member
Eagle-Wisecos are pretty much the cornerstone to 4g63 lower end building. Probably the best price for the power you can make on it. A lot of people can get into the 700hp range safely with that. After that you are looking at a new crank and turbo tuffs or some sort of I beam rod. ACL race bearings, mains and a 20g or 5858 you can drive 400hp all day long.
 

jeverts

Well-known member
I would agree with Coyote. On the other hand...you are already at the stage of putting in rods and pistons..spend the money and be done with it.
 

slugsgomoo

Well-known member
also unless you're going for insane power levels, building a forged internal engine with
 

tektic

Well-known member
I vote Eagle rods with 22mm wrist pin And the nipon 2g pistons with floating pin.
I think I'm going to be putting one of these together with my spare block.
 

coyotes

Well-known member
Quoting slugsgomoo:
One of my friends is building a 10:1 2.4L... that's where the hilarity factor goes straight to 11.



one of these years it'll run
 

slugsgomoo

Well-known member
machininst took a long time. The short block is actually assembled, but progress has been slow due to a couple other things. The car is fine on the stock bottom end though.
 

biglady112

Well-known member
Going to a larger 22mm wrist pin gains you no advantage if you still have a flacid wrist pin. When will people understand that? If you are going to make a big deal about it go with a quality material in a thickness that will actually benefit you. I would invest correctly if you are going that far. If you get a low end for like that or any rod for that matter have the machinists check for weight equality, bore sizing, pin fitment and if you go through with it please invest in a more modern design than a cheap ass $350 piston. In my eyes the heavier the better across the board. As with everything we start to get greedy and push things. Might as well over build it if you are in there.

With that said I have had tremendous luck with Arias pistons and either GRP aluminum or Pauter chromoly rods. I am going to say those are likely not economical or focused towards where this car will be used. Just remember, you get what you pay for.
 

GSTwithPSI

Well-known member
Tektic mentioned using a 22mm wrist pin because that's what standard 2G pistons come with, not because they are stronger. I'm assuming he said that due to the OP wanting to run 2G pistons hung on 6 bolt rod...A normal 6 bolt rod having a 21mm little end of course.

WTF is a flacid wrist pin anyways?
 

biglady112

Well-known member
Any off the shelf piece of shit .200" and thinner. The kind you get with cheap ass pistons.
 

tektic

Well-known member
The op asked for an economy build, and you suggest aluminum rods. Ok 3/4 of the budget down. /ubbthreads/images/graemlins/rofl.gif

Then after suggesting aluminum rods you say get the heaviest pistons you can find? Is that to make up for the weight lost using aluminum rods? Off the shelf Pistons are infered to all be shit. So custom heavy pistons with a wrist pin bigger than .200", so they are not flacid right?
 
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prove_it

Well-known member
I've had great luck with my eagle wisecos. I wish I had gone higher compression, but it was my first build. I do hate on my wisecos though. They make a crappy noise at idle once hot. No performance issues and I've gone 27k miles with no loss in compression. Just an annoying knocking type sound. When I do rebuild it again, I plan on going to 9.5:1 on JE or Mahle pistons. I've heard both brands hold up good in under 600whp builds. Got a buddy making 900whp on Mahle with no issues so far.

I do vote that if your building it, go for it. Do it now otherwise you'll regret not forging the bottom end. I did it to lose rotating weight, which is noticeable. I had a frozen pin on #4, so I needed parts anyway. It wasn't much more to run the eagle/wiseco combo anyway. I think it was about 400 bucks more than fixing the stuck pin.

Sure you don't NEED to, but seriously, do it once and be happy. Otherwise you'll want to rebuild it and then your on jackstands again and you grow to hate the car cause you can't drive it.
 

biglady112

Well-known member
Get the heaviest piston and rod you can. Plain and simple. The lighter is better thought does not apply when pushing a forced induction engine. And you will see that I did not recommend the rods first. Anyone considering investing needs to look past the basic 15 year old designs that are the cheapest options out there. For another $150-200 you can get a quality piston. And for those that do not know, make sure you invest in a quality wrist pin. The thin pins are crappy material and do not hold up to long term abuse. A motor I just tore down proves this. And get a thick pin as that is a key element people look past. The off the shelf ones are garbage and flex quite easily. I was pretty clear in what i thought would work, even though it is not in most folks budget. Regardless of what you spend, you better make sure the parts are right and not just assume.
 

Jesus_Negros

Well-known member
Possibly newb question here:

What is the benefit of a heavy piston/rod combination vs a lighter piston/rod combination on a forced induction engine?
 

biglady112

Well-known member
More material to take the abuse and girth for the durabilty/longevity. Something I learned racing at Bonneville. Just look at the diesel stuff and follow their lead. Each motor we have put together with heavier parts has just lasted and taken an ass whooping. 600-1000hp four cylinders wide open for five miles at a time. Multiple times in a day, for an entire week of racing. Of course issues arise and other things like head gaskets and such may not last
 

362Ryan

Well-known member
I'm with Biglady on this one.

I went with Wiseco HD's, tool steel wrist pins and K1 rods.

The machinist said the rods were some of the toughest he has worked with.
 

tektic

Well-known member
Quoting turbophein:
i wanted to build my own bottom over the winter for minimal investment while focusing on the details that really matter.

my goals are to have a strong built bottom end able to handle 500-600hp if i ever get there one day. 400hp reliably for 20k miles would be a dream come true i think.



When I see things like "if i ever get there one day" it makes me think this engine will never see more than a 16g turbo. A reliable 400hp makes me think he shouldn't even bother with a forged piston.

It Sounds to me like he wants an engine that starts in the cold and doesn't make noise, not one that can handle 1000hp.

Biglady; you may have the right answer, just not to this mans question.
 
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EMX5636

Well-known member
Quoting 362Ryan:
I'm with Biglady on this one.

I went with Wiseco HD's, tool steel wrist pins and K1 rods.

The machinist said the rods were some of the toughest he has worked with.



Not trying to divert too much off topic, but everything I've seen about K1 is they are the same as Eagle/Scat. I've been lucky with 9.0 Wiseco's, and R&R rods in mine, costly, but has been 100% reliable for close to 30k miles now at over 500whp.


And to answer the OP's question a bit more, your Eagle 2G setup is a decent cost effective one, but for not much more money, you can an off the shelf from various companies and have a higher window if you want that 5-600hp later on.

Are people still looking for the factory forged Evo9 pistons and installing them? It's been a few years since I've looked for factory parts builds.
 
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