Forged Internals vs Stock for sub 400hp in a daily

This. You actually bent a rod? Pretty rare failure compared to breaking a ringland or spinning a bearing.

Bending a rod takes talent. Anybody can blow a ringland. If you bend and twist a rod and then eject it from the engine block, now you have accomplished something. Original motor at 101k, low oil, max rpms at the track.

 

as for OP's original question, forged vs OEM. OEM. I have a forged motor and it worked great for what I wanted - track car. As a DD, it was a hassle waiting for it to warm up.

 

If you are working with a tuner/builder, you are paying them for advice & expertise. It will cost more to interfere with that process. If you have some specific requirements, discuss it with them and make sure they are listening. I interviewed one shop who kept telling me they knew what I needed...during the interview a recent delivery pulled up with a blown engine. I couldn't get away fast enough.

Edited May 10, 2016 by boxkita

^This. Hence the reason I went with Cosworth 4032 forged. More than fine at 350 whp-ish power levels.

Bending a rod takes talent. Anybody can blow a ringland. If you bend and twist a rod and then eject it from the engine block, now you have accomplished something. Original motor at 101k, low oil, max rpms at the track.

 

as for OP's original question, forged vs OEM. OEM. I have a forged motor and it worked great for what I wanted - track car. As a DD, it was a hassle waiting for it to warm up.

 

If you are working with a tuner/builder, you are paying them for advice & expertise. It will cost more to interfere with that process. If you have some specific requirements, discuss it with them and make sure they are listening. I interviewed one shop who kept telling me they knew what I needed...during the interview a recent delivery pulled up with a blown engine. I couldn't get away fast enough.

 

The builder has seen me add more and more bolts ons since I bought the car and his assumption was I will keep wanting power. So he suggested fully forged internals. But after discussing my concerns about longevity but balancing it with the pile of pistons with broken ringlands they have in the shop, the graded manley's seemed like a good idea. As long as I can warm it up by driving mellow and staying low revs it shouldn't be too bad. The primary people suggesting oem are people talking about high hp builds they've seen that have not blown a ringland yet. And I'd just like the peace of mind. You hear of random piston failures on stock cars all the time and so I just don't want to be unlucky in 60k miles.

 

What were the ptw clearances on your forged build? I've read many people using the A B manleys and being happy with them.

This is a case of wanting your cake and eating it!

 

Sub 400 build with future plans to add a dom 1.5? His build already seems 300+hp, he has upgraded air and fuel.

 

All his mods and planned mods, especially running e85 puts him in oem danger zone! Especially with his tuner! A dom 1.5 on e85 setup is a 400+ build easily.

 

You need a really good tuner, one with a dyno. Nothing wrong with a road tune, but from my experience you dyno to dial in , and then you road tune to make fine adjustments. But nothing wrong with road tunes in general, especially when they don't blow your engine in 15 mins . If you actually had at least a week, even a couple days, to see how your vf52 performed with e85, you would know where you want to be. It was short lived so you don't know if you may or may not want more horsepower....... if you go with a bigger turbo and e85, i'd go forged. If your going to stick with ur vf52, oem is fine. What does suck is to find you want more power after using oem block.

 

But longevity and high horsepower don't usually go hand in hand. As hp goes up longevity goes down!

^This. Hence the reason I went with Cosworth 4032 forged. More than fine at 350 whp-ish power levels.

 

 

How long have you been running this? I used to be a fan of the Cossie pistons but a few users found the (very thin) rings wore out prematurely. In retrospect it does seem odd to offer the street-friendly 4032 piston with very race-oriented narrow ring kits.

 

 

Sent from a device using some software.

Thats seem more like a better than stock usage.

 

Stock block can take around 400whp "reliably", i think any piston can run reliably under 400.

 

I think this op wont be content with sub 400, it takes one to know one, he has the bug... if he goes 20g on e85 he is over 400, with proper tuning!

 

4032 is probably fine for 500 or below. But if you want to get super cereal in the future and push rpm past stock 6k, i'd go 2618!

 

Race engine for some is daily driver for others... its all perspective.

 

Remote start makes warming up car a lot easier when u run forged.

Edited May 11, 2016 by Tehnation

Thats seem more like a better than stock usage.

 

Stock block can take around 400whp "reliably", i think any piston can run reliably under 400.

 

I think this op wont be content with sub 400, it takes one to know one, he has the bug... if he goes 20g on e85 he is over 400, with proper tuning!

 

4032 is probably fine for 500 or below. But if you want to get super cereal in the future and push rpm past stock 6k, i'd go 2618!

 

Race engine for some is daily driver for others... its all perspective.

 

Remote start makes warming up car a lot easier when u run forged.

 

I dont see myself going bigger then dom 1.5 on e85 because I don't want to wait till 4500 to feel boost, so that limits me to the 400hp range. This car has car seats in it, and there is a limit to how much power I can use on the highway without getting my license taken from me and my kids kept alive. 500 hp is just not going to happen. If I start looking at that then I'll buy a dedicated track car.

 

As for 4032 vs 2618 there is more evidence for 4032 piston breakage from what I've read on nasioc and since there is not a graded a b drop in for 4032 like the manley's I'll have to pay more for machine work. In addition the ptw for the graded manleys is .0023-.0031 which seems to be in the same range is what people get boring and honing with 4032 pistons. In some reports even tighter. That with the offset wrist pins and coated skirts makes me think the manley's are probably the safest bet for reliability. I don't have to rely on a machine shop getting it right and also not and paying extra for the chance.

 

I would absolutely stay oem except I am not certain the ringlands will last 90k with my vf52 on e85, and I am even less certain that the dom 1.5 would be safe with stock pistons. Heck my vf52 holds 17.+ psi to redline so I might be able to get more then 330 out of it on e85.

 

I have a few days yet before he drops the manley's in even though the parts are already ordered, so if someone wants to convince me that the oem can take it or that 4032 is better then 2618 I'm all ears.

 

Until Boxita showed up with that long post history and "moderator" status I was accepting the sage advice of the respected Mr. Fahr.

Edited May 11, 2016 by xtea

thats the thing ..... a dom 1.5 on e85 is 400+...... lol

Rootbeer most likely just blew a ringland on newish block. Yeah, oem pistons can go take a hike.

I dont see myself going bigger then dom 1.5 on e85 because I don't want to wait till 4500 to feel boost, so that limits me to the 400hp range.

The 1.5XTR on a 2.5 spools like an 18G.

500 hp is just not going to happen. If I start looking at that then I'll buy a dedicated track car.

Every non-caged Subaru I've been in that had over about 450whp felt as sketchy as ****... like 'I was lucky the engine didn't get it's way and tear the car apart' kind of sketchy.

As for 4032 vs 2618 there is more evidence for 4032 piston breakage from what I've read on nasioc and since there is not a graded a b drop in for 4032 like the manley's I'll have to pay more for machine work.

Not just pay for machine work but also 1) give up the very good factory hone on the cylinders in exchange for whatever your shop can pull off (and we know how that can vary), 2) break apart the bottom end for really no good reason.

In addition the ptw for the graded manleys is .0023-.0031 which seems to be in the same range is what people get boring and honing with 4032 pistons. In some reports even tighter.

I run mine at 0.08mm PTW clearance. It's not recommended to run them tighter, even though many do get away with it. There are consumers that want the reliability of forgies, or just the bragging rights. They don't want extra noise or oil consumption or anything else and they insist the builder uses a tighter PTW clearance than the piston manufacturer recommends. All is well until the first time they go to the track or even do a longer or harder than usual run up a pass road.

 

I run mine at 0.08mm PTW clearance. It's not recommended to run them tighter, even though many do get away with it. There are consumers that want the reliability of forgies, or just the bragging rights. They don't want extra noise or oil consumption or anything else and they insist the builder uses a tighter PTW clearance than the piston manufacturer recommends. All is well until the first time they go to the track or even do a longer or harder than usual run up a pass road.

 

So, it should be obvious I have no clue what I am talking about. That said .003 is 25 times smaller then .08. I am pretty sure I saw some folks saying their own bore and hone to match their purchased pistons led from .0015 to .005, with .005 claiming to be loose. So, how much stupid did I just type out?

Metric... 0.08mm is about 0.0031"

Oops, I thought both measurements were metric.

Hi Fahr, just started down the road with this 4032 motor. It's got about 4 track days on it so far. I'll take it for the odd weekend backroad toss but it's essentially a track toy now, (everything aft of the front seats gutted, etc). Shockingly, I got 7 years of daily driving and many track days each season at 300whp -ish with not a peep until a ringland finally let go last year. I mostly chalk that longevity up to the excellent tuning chops at Cobb here in Portland. The car now has the Cossy plugs with upgraded rods,bearings, valves-stock size, springs. Edited May 12, 2016 by shralp

Turns out it was a spin rod bearing, not a bent rod. So oiling issues.

Turns out it was a spin rod bearing, not a bent rod. So oiling issues.

 

Thanks for following up with that. Adds a lot of value to this interesting thread.

Yeah i run a billet 18g with a stock block. 335whp/377wtq all the supporting mods. 22.5psi daily driven with 111k on it so far. 21k on the 18g setup. Stock is quite strong with a good tuner. When mine finally blows a head gasket of ring from bad gas or bad coil what ever I already have a plan.

Arp head bolts,Cosworth pistons with oem sti rings. sti crank balanced, BC rods, king bearings. WPC coated rings, bearings, pistons, crank and pins.

Its a mix of what a few companies do for their builds. Stout motor With longevity for a dd.

IMO DD under 500whp shouldn't be using 2618 pistons. Cosworths are race proven realiable even Mahle 4032 are proven up to 450whp. Wossiner is also available and they are designed for porche 911's.

Their are even Ceramic pistons coming out for our engines. Not your ceramic dinner ware. ceramic's that are used in diesel tractor pull trucks.

Yeah i run a billet 18g with a stock block. 335whp/377wtq all the supporting mods. 22.5psi daily driven with 111k on it so far. 21k on the 18g setup. Stock is quite strong with a good tuner. When mine finally blows a head gasket of ring from bad gas or bad coil what ever I already have a plan.

Arp head bolts,Cosworth pistons with oem sti rings. sti crank balanced, BC rods, king bearings. WPC coated rings, bearings, pistons, crank and pins.

Its a mix of what a few companies do for their builds. Stout motor With longevity for a dd.

IMO DD under 500whp shouldn't be using 2618 pistons. Cosworths are race proven realiable even Mahle 4032 are proven up to 450whp. Wossiner is also available and they are designed for porche 911's.

Their are even Ceramic pistons coming out for our engines. Not your ceramic dinner ware. ceramic's that are used in diesel tractor pull trucks.

 

How is the spool with your billet 18g?

So no one but Fahr Side likes the Graded Manley drop ins for a new block? Are there graded 4032's that don't require splitting the block? Edited May 13, 2016 by xtea

Well, Builder is already in the middle of putting the manley's in now. Here's hoping I didn't screw this up.

So no one but Fahr Side likes the Graded Manley drop ins for a new block? Are there graded 4032's that don't require splitting the block?

 

You aren't asking builders / tuners. You are asking people who have had 1-3 engines built for them.

 

I think there is a lot to be said for actual experience and not forum experience

 

(my forum experience is that almost every single LGT has a blown turbo or cracked ringland, but I don't have the data to back that up from the USDM market)

 

When a builder / tuner (with a good reputation) recommends something, I think their recommendations should be taken a little more seriously.

 

Are you buying a new OEM SB and installing the graded pistons?

Edited May 13, 2016 by Rhitter

You aren't asking builders / tuners. You are asking people who have had 1-3 engines built for them.

 

I think there is a lot to be said for actual experience and not forum experience

 

(my forum experience is that almost every single LGT has a blown turbo or cracked ringland, but I don't have the data to back that up from the USDM market)

 

When a builder (with a good reputation) recommends something, I think their recommendations should be taken a little more seriously.

 

Are you buying a new OEM SB and installing the graded pistons?

 

New oem with gradeds and arp studs.

 

The shop has a great local rep and I've had the best experience with them of the 3 local subie shops that deal with performance cars. Their race history isn't as extensive as some other local shops here but their customer service and communications is the best from my personal experience. They have not been working with the manleys long enough to see how long they will go though which makes sense since they've only been on market for 3 years.

When a builder (with a good reputation) recommends something, I think their recommendations should be taken a little more seriously

 

Most statements made here aren't more true than this one. Unless you are a remarkable individual, you or most of the others here don't know more than your tuner. That's why people are paying him to tune and build these cars instead of all of the members here who bench tune and build with no working knowledge. Different tuners/builders have different tuning "styles" and preferences, hence the different recommendations. It all comes back to that old saying: "there is more than one way to skin a cat." as long as you get YOUR desired outcome who cares what worked best for the last guy? Take the advice from a reputable tuner, he is still in business for a reason. I let the advice of an expert take priority over the advice of the guy who's just really good at installing bolt-ons. In the long run, you will get a better tune if you install what your tuner/builder is comfortable working with. You are paying for THEIR knowledge.

Edited May 13, 2016 by 762x39

The builder has seen me add more and more bolts ons since I bought the car and his assumption was I will keep wanting power. So he suggested fully forged internals.

Sounds like your builder was trying to give you good advice. However if you have been bolting on parts for awhile and he's just getting to suggesting you need forged internals, suggests 1 of 2 things. Either you don't have a plan for what you want or your builder hasn't mastered the concept of the the up-sell.

 

But after discussing my concerns about longevity but balancing it with the pile of pistons with broken ringlands they have in the shop, the graded manley's seemed like a good idea.

Longevity vs forged vs ringland failures are not inter-related. If you want longevity, 21psi is not in your future unless you spending alot of money on the supporting mods. Bolt-ons are synonymous with ring-land failures.

 

As long as I can warm it up by driving mellow and staying low revs it shouldn't be too bad.

A forged motor warmup means idling in your driveway until the water/oil temp have reached operating temp. As soon as you release the clutch, you're doing damage and risking failure. My engine warm up regardless of lateness was always 3 minutes. On colder days it was 5 minutes.

 

The primary people suggesting oem are people talking about high hp builds they've seen that have not blown a ringland yet.

The primary ppl suggesting high hp builds on oem are internet trolls. It's your money. If you are not talking to, visiting with, reading their tales of woe; then why are you concerned with their advice. I never had a ring-land failure, but did have a rod get bent, twisted, burnt and finally turned into a brittle mass of metal. The piston top was cracked but the ringlands were still intact (cracks were vertical across them). When I started looking for my new engine. I talked to the "engineers" on this forum. Read everything I could find about high-torque race motors. And talked to alot of builders.

 

And I'd just like the peace of mind. You hear of random piston failures on stock cars all the time and so I just don't want to be unlucky in 60k miles.

"Random piston failures all the time" = boltons on tired engines with poor oil maintenance. It wasn't that long ago that 100hp/Liter was a super car motor. Now you're driving one on the street to the grocery store. In your great expertise, you have bot a number of "bolt-on" parts to increase the hp of your supercar motor. The 60k failures are bolt-ons without plans and oil change intervals in the JiffyLube realm.

 

What were the ptw clearances on your forged build? I've read many people using the A B manleys and being happy with them.

Something crazy 35? Mine sounds like a diesel truck until warm. However, I was looking for an endurance motor for long track days. At 6000 rpms for an hour at time, is where I wanted my clearances set. The rest of the time, I dealt with long warm up times. I routinely drove on the street 2 gears down to keep the rpms up, that it gave stupid fast acceleration was of no consideration.

 

You want a 21psi motor, build for much higher and de-tune. A de-tuned motor is overbuilt and will have more headroom for oops. A motor that barely gets to 21psi by pushing every parameter is a rebuild waiting to happen.

 

My motor went on the dyno at 21 psi and got 369 torque. I had it turned down to 19.2 with torque at 335. Unlike a peaky barely there 21psi bolt-on build, I have 335 torque from 4000-7000 rpms. So while your waiting for the rpms to wind up enough to upshift, I'm still pulling hard. On the track, meant I could catch someone even if I got stuck on the wrong end of a 2-3 upshift. On the road, it meant I had alot of fun in traffic.

 

"I want 400hp" is not a plan. "I want to be able to DD my car without warming it up, have some fun in traffic, get 22mpg, and do 2 autox a year" is a mission statement. Then fill in how much hassle you can live with. Add in how much maintenance you want to pay. now add up how much money you can put into the project. Now found someone you can work with and double the amount of money you think you need.

 

From your comments, a forged motor is not in your future. A 400hp LGT is a stupid fast car, emphasis on stupid. Read the build threads of the people who are on this list - http://legacygt.com/forums/showthread.php/official-fastest-legacy-thread-1-4-and-1-8-184089.html . Everyone in the top 5 has built more than 1 motor.

Well, Builder is already in the middle of putting the manley's in now. Here's hoping I didn't screw this up.

Well you're screwed at the point. Start saving for your next engine. no plan = rebuild