Forged Internals Build 10:1 vs 9:1 compression pistons????

[mrhighcaliber]

Im planning to build my engine, Manley forged pistons and rods.

10:1 stock comp vs 9:1 reduced comp.

General Rule of thumb is less comp+boost+more timing = more power reliably on pump 93.

Is there a performance benefit to going with the 9:1 pistons on the Ecoboost 3.5, or are the 10:1 stock compression piston fine?





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[SM105K]

Are you only interested in running 93? If so yes that would be good combo. Most of my turbo LS motors were in the 9:1 compression ratio area for that exact reason.

IIRC you already have upgraded turbos correct?

 

[mrhighcaliber]

Are you only interested in running 93? If so yes that would be good combo. Most of my turbo LS motors were in the 9:1 compression ratio area for that exact reason.

IIRC you already have upgraded turbos correct?

93 to E30 of course. Yea, upgraded turbos. Just wondering if this 9:1 might be more optimal for this engine or if 10:1 is already optimal. I'm hope some tuners chime in as well.

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[FiveLeeter918]

Personally haven't seen anyone have a benefit for 9:1 on these car. a high horsepower v8, sure. but I don't think you'd ever see enough power to take advantage of a 9:1 compression ecoboost engine.

 

[802SHO]

Maybe go ahead with 9:1 if it won't hurt and will potentially make a difference.

 

[Ecoboost_xsport]

Fyi, I know it's a different platform and has some differences, but most of the high output 3.5L Raptors are running 10:1.

I'm having a built motor being done right now as well via Ryan at RMB Motorworks. 10:1 CR, closed deck, Gen2 Raptor Crank, and all the other built internal goodies (their stage 2). I'm not as far along in the process as BPD, but will hopefully have some updates within the next few weeks

 

[SM105K]

Maybe go ahead with 9:1 if it won't hurt and will potentially make a difference.

I think it would be a good idea if could use all of the upgraded turbos. However, at the power level...you are literally pulling the pin on a live grenade that we call the 6f55.....

 

[SHOdded]

https://www.full-race.com/articles/inside-the-ecoboost-f-150/
Forged rotating assembly in the F150.

http://www.supersixmotorsports.com/_pdf/2016/cyclone-tech-v2.pdf
Cyclone 3.5L EcoBoost, 3.5 Duratech and 3.7L Ti-VCT V6 Engine Tech

https://rehermorrison.com/tech-talk-93-all-about-connecting-rods/

HTH

Until some time ago, ecopowerparts used to carry CP-Carillo stuff
https://www.enginelabs.com/engine-t...-forged-ecoboost-rods-new-cp-piston-forgings/

 

[Ecoboost_xsport]

I think it would be a good idea if could use all of the upgraded turbos. However, at the power level...you are literally pulling the pin on a live grenade that we call the 6f55.....

Tell me about it. I don't really know how significant that GH torque converter will be when it comes to high output transverse 3.5L and when I called Circle D, they basically said "yeah we don't do much with those TCs, we basically take a stock one and make some minor changes" and then told me "for what you are spending, it's not worth it", Not very inspiring when a company isn't too enthused about selling one of their own products, LOL. Not knocking Circle D's quality, just that it's a bit of a downer when a well known TC company doesn't feel very excited about something they sell being very effective.

Between the 6F55 and the PTU...smh. I'm still gonna do what I can with it, but I don't disagree.

 

[SM105K]

Tell me about it. I don't really know how significant that GH torque converter will be when it comes to high output transverse 3.5L and when I called Circle D, they basically said "yeah we don't do much with those TCs, we basically take a stock one and make some minor changes" and then told me "for what you are spending, it's not worth it", Not very inspiring when a company isn't too enthused about selling one of their own products, LOL. Not knocking Circle D's quality, just that it's a bit of a downer when a well known TC company doesn't feel very excited about something they sell being very effective.

Between the 6F55 and the PTU...smh. I'm still gonna do what I can with it, but I don't disagree.

The 6f55 is junk....I agree. Years ago Circle D made a converter for our platform. It actually was promising, until it was tested at the track and went .5 seconds slower then the stock converter. Lol. So there is a reason Circle D isnt interested or very excited.


The PTU is alot stronger then they are given credit for. They really don't fail from being over powered. Details below from MrHighCaliber (the OP):

"PTU's don't fail at least not from a power handling perspective. These only fail from lack of maintenance. Spun bearings and galling of the gears from lack of lubrication.

High Heat dries up the lighter oil molecules in the ****, which causes more heat due to lack of lubrication (thermal runaway) which leads to the remaining gear oil turning to thick black paste which clogs up the vent tube in the ptu which cause pressure buildup in the ptu which forces the remaining, non-congealed fluid out past the shaft seals. Now the only left is a thick paste thats easily flung off of the gears, sticking only to the case. After this chain of events, the bearings run dry and begin to fail, next are the gears. Tolerances widen or things begin to sieze. Bearing and gear noise are usually the first signs of mechanical failure.

But the PTU internals are stout. The weakest part of our powertrain is the RDU Atc coupler. (The electronic coupler in the rear differential). At least in terms of tq capacity and power handling."

 

[stripSHO]

It probably depends mostly on whether the turbos can feed enough to capitalize on the 9:1. Do any of the bolt-on turbo offerings even have compressor maps available? I've searched many times but never spotted one. Would be super helpful in making this determination!

Anyway, it would allow an extra 3-4 psi of boost with the same effective compression as a 10:1 engine, giving you room for more timing at a given load.

Iirc manufacturers mainly choose higher compression because they get better cruising efficiency from it.

Page 4 of this blower manual has a handy effective compression chart based on boost and static compression: https://www.google.com/url?sa=t&sou...FjADegQIBhAB&usg=AOvVaw1cU1r3WqkA5k6J3u6Su7r9

 

[SM105K]

It probably depends mostly on whether the turbos can feed enough to capitalize on the 9:1. Do any of the bolt-on turbo offerings even have compressor maps available? I've searched many times but never spotted one. Would be super helpful in making this determination!

Anyway, it would allow an extra 3-4 psi of boost with the same effective compression as a 10:1 engine, giving you room for more timing at a given load.

Iirc manufacturers mainly choose higher compression because they get better cruising efficiency from it.

Page 4 of this blower manual has a handy effective compression chart based on boost and static compression: https://www.google.com/url?sa=t&sou...FjADegQIBhAB&usg=AOvVaw1cU1r3WqkA5k6J3u6Su7r9

If you do some digging, you can find Matt from Gearhead actually has the compressor maps from the stock turbos and from his upgraded turbos for comparison. I might be able to find them.

 

[stripSHO]

If you do some digging, you can find Matt from Gearhead actually has the compressor maps from the stock turbos and from his upgraded turbos for comparison. I might be able to find them.

I thought he might, but never bothered reaching out as it's just mostly curiosity for me at this point. I just wish more merchants just posted the datasheets of what they're trying to sell you!

The 9:1 pistons seem like a no-brainer and I wouldn't even hesitate on it but that is just me. I'd love to learn a reason not to use them.

 

[SM105K]

I thought he might, but never bothered reaching out as it's just mostly curiosity for me at this point. I just wish more merchants just posted the datasheets of what they're trying to sell you!

The 9:1 pistons seem like a no-brainer and I wouldn't even hesitate on it but that is just me. I'd love to learn a reason not to use them.

I agree 100% with logic you posted before. The problem with our platform even with the 10:1 setup is the damn transmission. Jordan still hasn't maxed the GH turbos and he is making good power, however that trans is ******.....

 

[Jordan_R]

I agree 100% with logic you posted before. The problem with our platform even with the 10:1 setup is the damn transmission. Jordan still hasn't maxed the GH turbos and he is making good power, however that trans is ******.....

We've got most the bugs worked out as some tuning issues. Essentially the trans tuning from before the upgraded turbos wasn't working as intended because the car was basically accelerating so quickly the trans was like WTF. So for the most part things are sorted however she's definitely not the happiest she's been I'd assume. Exactly why the car is on a very strict diet right now to keep the load off. In fact I am going to go do a trans drain and fill right now..

 

[802SHO]

If you do some digging, you can find Matt from Gearhead actually has the compressor maps from the stock turbos and from his upgraded turbos for comparison. I might be able to find them.

Peasant!

 

[Zpak]

I am going to go do a trans drain and fill right now..

Hold the sarcasm

 

[limited02]

I’d go more compression and less boost.

 

[SM105K]

Peasant! View attachment 12964 View attachment 12965

Touche...you got me.

 

[Jordan_R]

Hold the sarcasm

Lol, I actually did.