Increased displacement? - Toyota GR86, 86, FR-S and Subaru BRZ Forum & Owners Community

Shadowsong6 · 02-06-2013, 09:26 AM

There is plenty of talk about turbos and superchargers, but what about good old natural aspiration? Has anyone tried to bore or stroke the engine yet? 2.5l shouldn't be too far fetched should it?

HunterGreene · 02-06-2013, 09:33 AM

Depends on how thick the sidewalls are. One of my friends had his tC1 engine bored from 2.4 to 2.7L. Granted, this was with a turbo, but the cylinder side walls have to be taken into account. I have a feeling with boring, you aren't going to see more than 2.2-2.3L max.

Dimman · 02-06-2013, 10:01 AM

I think a shop or two here are looking into a frankenstein 2.5L FA25. FA20 heads on an FB25 block. There was also talk of the FB25 crank in an FA20 (don't know which rods, or other stuff needed) which would make a 2.4L FA24 (?).

We'll see if anything happens.

mad_sb · 02-06-2013, 10:07 AM

Very expensive for the gains. Plus keeping the motor square = deep rev (some are saying 9K on stock valve train but that is crazy piston speed) = power potential with proper cams etc. Combined with Forced Induction... you can run a larger turbo with less lag, but again, if the bore and stroke limits the rev potential you won't get as much benefit from the bigger turbo...

Shadowsong6 · 02-06-2013, 10:32 AM

I'm not really looking to turbo, if I used any kind of f/I it would be a supercharger, I like the feel of a na engine, superchargers still maintain some of the n/a feel. That FA24 frankenblock with a supercharger, some cams, and maybe some meth injection sounds interesting to me.

OrbitalEllipses · 02-06-2013, 10:34 AM

Quote:

Originally Posted by Shadowsong6

That FA24 frankenblock with a supercharger, some cams, and maybe some meth injection sounds interesting to me.

With a fully blueprinted and balanced rotating assembly revving to 8.5K-9K, titanium valves/retainers/springs....

turbo_jimbo · 02-06-2013, 12:08 PM

You can't bore these engines because of the sleeve material. However, the new Darton sleeves can be bored.

I wonder if people misunderstand what blueprinting an engine really entails...

OrbitalEllipses · 02-06-2013, 12:42 PM

Quote:

Originally Posted by turbo_jimbo

You can't bore these engines because of the sleeve material. However, the new Darton sleeves can be bored.

I wonder if people misunderstand what blueprinting an engine really entails...

You'd be surprised how many people don't check clearances on an engine build (durrrr drop in pistons yay! durrrrr); so yes, I want a fully blueprinted engine in that regard.

Shadowsong6 · 02-06-2013, 01:35 PM

Since we are on the subject, has anyone started developing cams yet?

carbonBLUE · 02-06-2013, 02:06 PM

Quote:

Originally Posted by turbo_jimbo

You can't bore these engines because of the sleeve material. However, the new Darton sleeves can be bored.

I wonder if people misunderstand what blueprinting an engine really entails...

please explain... (seriously i have no idea what the sleeves are made of)

Quote:

Originally Posted by OrbitalEllipses

You'd be surprised how many people don't check clearances on an engine build (durrrr drop in pistons yay! durrrrr); so yes, I want a fully blueprinted engine in that regard.

yeah lots of "shops" do that lol

Quote:

Originally Posted by HunterGreene

Depends on how thick the sidewalls are. One of my friends had his tC1 engine bored from 2.4 to 2.7L. Granted, this was with a turbo, but the cylinder side walls have to be taken into account. I have a feeling with boring, you aren't going to see more than 2.2-2.3L max.

i hope that answers your question... for an open deck block... they are pretty decent...

carbonBLUE · 02-06-2013, 02:09 PM

Quote:

Originally Posted by Shadowsong6

Since we are on the subject, has anyone started developing cams yet?

http://www.hks-power.co.jp/en/produc...s86/index.html

in development by hks, but other than that i dunno

industrial · 02-06-2013, 02:55 PM

Quote:

Originally Posted by Shadowsong6

Since we are on the subject, has anyone started developing cams yet?

I'm waiting for this too. I've tried contacting Ferrea since they are working on valvetrain components. I'm assuming that if they are testing valvetrain components for NA power and high revs, they'd have a cam in there that could take advantage of it. A ferrea rep casually threw out there that their NA kit was making 250hp at SEMA.

I'll go this way eventually. High lift, high duration cams with valvetrain upgrades and maybe a mani/tb upgrade. Hopefully good for ~220-250whp at 8500-9500rpm. No idea since nobody is releasing any info.

Captain Insano · 02-06-2013, 09:41 PM

Cant wait to see some of this stuff evolve.

wparsons · 02-07-2013, 05:11 PM

Quote:

Originally Posted by OrbitalEllipses

With a fully blueprinted and balanced rotating assembly revving to 8.5K-9K, titanium valves/retainers/springs....

I believe some people are revving to ~8500rpm on 100% stock internals without issues.

02-06-2013, 09:26 AM	#1
Shadowsong6 Senior Member Join Date: Oct 2009 Drives: 2014 Ford Mustang Location: Conroe, Texas Posts: 134 Thanks: 9 Thanked 9 Times in 8 Posts Mentioned: 0 Post(s) Tagged: 0 Thread(s)	Increased displacement? There is plenty of talk about turbos and superchargers, but what about good old natural aspiration? Has anyone tried to bore or stroke the engine yet? 2.5l shouldn't be too far fetched should it?

02-06-2013, 10:07 AM	#4
mad_sb Senior Member Join Date: Jan 2013 Drives: 2013 Asphalt FR-S Location: Orange County Posts: 1,639 Thanks: 632 Thanked 981 Times in 537 Posts Mentioned: 100 Post(s) Tagged: 0 Thread(s)	Very expensive for the gains. Plus keeping the motor square = deep rev (some are saying 9K on stock valve train but that is crazy piston speed) = power potential with proper cams etc. Combined with Forced Induction... you can run a larger turbo with less lag, but again, if the bore and stroke limits the rev potential you won't get as much benefit from the bigger turbo... __________________ ~Namaste~ 2013 Asphalt FRS

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02-06-2013, 09:33 AM	#2
HunterGreene Hail Magnet Join Date: Jun 2012 Drives: Firestorm FR-S: "Artemis" Location: Cleveland, OH Posts: 4,578 Thanks: 3,386 Thanked 3,195 Times in 1,633 Posts Mentioned: 43 Post(s) Tagged: 2 Thread(s)	Depends on how thick the sidewalls are. One of my friends had his tC1 engine bored from 2.4 to 2.7L. Granted, this was with a turbo, but the cylinder side walls have to be taken into account. I have a feeling with boring, you aren't going to see more than 2.2-2.3L max.

02-06-2013, 10:32 AM	#5
Shadowsong6 Senior Member Join Date: Oct 2009 Drives: 2014 Ford Mustang Location: Conroe, Texas Posts: 134 Thanks: 9 Thanked 9 Times in 8 Posts Mentioned: 0 Post(s) Tagged: 0 Thread(s)	I'm not really looking to turbo, if I used any kind of f/I it would be a supercharger, I like the feel of a na engine, superchargers still maintain some of the n/a feel. That FA24 frankenblock with a supercharger, some cams, and maybe some meth injection sounds interesting to me.

02-06-2013, 12:08 PM	#7
turbo_jimbo Member Join Date: Jan 2013 Drives: 01 MR-s, 78 280z, 13 FR-s Location: Las Vegas Posts: 68 Thanks: 3 Thanked 15 Times in 11 Posts Mentioned: 1 Post(s) Tagged: 0 Thread(s)	You can't bore these engines because of the sleeve material. However, the new Darton sleeves can be bored. I wonder if people misunderstand what blueprinting an engine really entails...

02-06-2013, 01:35 PM	#9
Shadowsong6 Senior Member Join Date: Oct 2009 Drives: 2014 Ford Mustang Location: Conroe, Texas Posts: 134 Thanks: 9 Thanked 9 Times in 8 Posts Mentioned: 0 Post(s) Tagged: 0 Thread(s)	Since we are on the subject, has anyone started developing cams yet?

02-06-2013, 09:41 PM	#13
Captain Insano Senior Member Join Date: Sep 2012 Drives: 2014 Jeep Wrangler RubiconX Location: Midwest, USA Posts: 1,282 Thanks: 110 Thanked 292 Times in 224 Posts Mentioned: 7 Post(s) Tagged: 0 Thread(s)	Cant wait to see some of this stuff evolve.

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