Would you guys prefer FB20 or FB25 for NA FT?

[Exage]

I think it's harder to find a GE, GTE, GUE, GZE engine that didn't have a single input from Yamaha than those that have. It looks to me that the 2000GT was manufactured by Yamaha, and a lot of their input was not only put into the 3M engine but the car as whole.

Something just occurred to me... Yamaha working on a high revving DOHC engine displacing 2.0L is very deja vu if not a little ironic.

I mean they started by creating a 2.0L in what is regarded by most as Japans first exotic sports car, now 45 years later same displacement just in a affordable global sports compact.

[old greg]

Originally Posted by Dimman

Our hypothetical motor could have more valve area (larger bore), and safely rev higher (less stroke) to take advantage of the extra flow.

I doubt they'd rev it higher, more likely the redline would be slightly lower to bring the rebuild interval back into daily-driver territory.

[Dimman]

Originally Posted by old greg

I doubt they'd rev it higher, more likely the redline would be slightly lower to bring the rebuild interval back into daily-driver territory.

That was more of a maximum potential comparison with the Formula Atlantic 4AGE.

The hypothetical short stroke motor in a production car, I would guess 8000-8500 rpm redline, and tuners pushing it to 5 figures.

The differences between the Toyota 7M and 1JZ L6s' strokes is even a bit bigger than our hypothetical motor, but there was only a less than 1000 rpm increase in the 1JZ's redline.

[SCIONIZED]

All this this boring stroked out turbo 2.0,2.5lt gives me a headache. lol What about the Subaru 3.6 flat 6 boxer @ 256hp and 247 lb.ft. torque with a turbo???? Whatever it takes just give me 300 hp+ paleeese! I would also like to see the lineatronic CVT transmission. If leave it in the automatic mode you get better performance and fuel economy or you can use as 6 speed manual mode. Any thoughts here?

[Dimman]

My god I want this hypothetical de-stroked FB25 sooooo badly! 94mm bore X 72mm stroke.

Check this out: Same bore as the 2GRFSE. So using almost the exact same specs for combustion chamber, ports, valves, CR etc... So...

205 hp @ 7500 rpm (based on the amount of air the 2GR is moving to make its 306 hp @ 6400 rpm)

That sound good with an 8000-8500 rpm redline?

Edit: This could be a very legitimate high-performance 2.0L, build the bottom strong so Subaru could boost it for the next WRX or STI.

[SCIONIZED]

Originally Posted by Dimman

My god I want this hypothetical de-stroked FB25 sooooo badly! 94mm bore X 72mm stroke.

Check this out: Same bore as the 2GRFSE. So using almost the exact same specs for combustion chamber, ports, valves, CR etc... So...

205 hp @ 7500 rpm (based on the amount of air the 2GR is moving to make its 306 hp @ 6400 rpm)

That sound good with an 8000-8500 rpm redline?

Edit: This could be a very legitimate high-performance 2.0L, build the bottom strong so Subaru could boost it for the next WRX or STI.

check out this site it talks about the engine in the FR-S.
http://www.insideline.com/scion/fr-s...nts_sort_form1

[Dimman]

Originally Posted by SCIONIZED

check out this site it talks about the engine in the FR-S.
http://www.insideline.com/scion/fr-s...nts_sort_form1

Ok, I'll do some more fancy imagination stuff.

2ZZGE bore is a touch smaller than the regular regular FB20. If the 2ZZ's porting, cams, combustion chamber, valves, etc... were matched to the FB20's bottom, it could put out 180 hp @ 6800 rpm.

D4-S added about 11% to the hp on the 2GR, at 3% more rpm. If we could imagine there is that much room for improvement on the 2ZZ design (which I doubt, as it already had a pretty high compression ratio), we would be at around 200 hp @ 7000 rpm. But given the longish stroke on the FB20, this is pushing it for reliability. Any more power mods would likely involve opening it up, and throwing in new rods. $$$

My buddy's crazy 7M (91mm stroke) only redlines (hard rev limiter) at 7600 rpm, but he has custom Cunningham titanium, rifle-drilled rods. (And 1015 whp on spray...)

The hypothetical de-stroked FB25 would be able to make more power after mods too, due to more available valve area for flow. And due to the short stroke being able to safely run to higher rpm to be able to take advantage of the extra flow potential.

Edit: Also the hypothetical motor based on the 2GR heads, doesn't need the lift component of the VVTL-i to make its numbers.

[Exage]

I really have been mulling over putting realistic theoretical specs on this marvellous engine we want on the tech thread. Might be fun to compare it to the engine that's released and see how far (or close?) we were to it.

[Dimman]

Originally Posted by Exage

I really have been mulling over putting realistic theoretical specs on this marvellous engine we want on the tech thread. Might be fun to compare it to the engine that's released and see how far (or close?) we were to it.

Sounds good.

[xantonin]

Originally Posted by Dimman

2ZZGE bore is a touch smaller than the regular regular FB20. If the 2ZZ's porting, cams, combustion chamber, valves, etc... were matched to the FB20's bottom, it could put out 180 hp @ 6800 rpm.

D4-S added about 11% to the hp on the 2GR, at 3% more rpm. If we could imagine there is that much room for improvement on the 2ZZ design (which I doubt, as it already had a pretty high compression ratio), we would be at around 200 hp @ 7000 rpm. But given the longish stroke on the FB20, this is pushing it for reliability. Any more power mods would likely involve opening it up, and throwing in new rods. $$$

On the Celica forum I believe the 2ZZ-GE NA record is 240 HP.

[Dimman]

Originally Posted by xantonin

On the Celica forum I believe the 2ZZ-GE NA record is 240 HP.

The example I was getting at was if the FB20 could duplicate a stock 2ZZGE's head properties, the FB20 would make 180 hp at about 6800 rpm.

I don't think the addition of the D4-S would be as significant on this as on the 2GR, because the 2ZZGE is so much better to begin with. For example the 2GR with the D4-S is like 11.8:1 CR, but that is not much more than a standard 2ZZGE, I believe? So there wouldn't be as much gain from that.

For a stock motor, maintaining reliability, etc... It would be pretty tough to improve on the 2ZZGE. Especially with the FB20's longer 90mm stroke.

[Crashoverride]

Originally Posted by Dimman

My buddy's crazy 7M (91mm stroke) only redlines (hard rev limiter) at 7600 rpm, but he has custom Cunningham titanium, rifle-drilled rods. (And 1015 whp on spray...)

The hypothetical de-stroked FB25 would be able to make more power after mods too, due to more available valve area for flow. And due to the short stroke being able to safely run to higher rpm to be able to take advantage of the extra flow potential.

very cool

[Dimman]

Originally Posted by Crashoverride

Tell Dwane I said hi..LOL

Were you up for PACNW last summer? Get to hear those rods spinning on the fly-by? Sex.

[OldSkoolToys]

Originally Posted by Dimman

(And 1015 whp on spray...)

Wait, whoa, how did this escape my notice? What's his HP non-spray? Thats INSANE for a 7M.

I'm a little behind the times on its tuning levels, but last I checked, ~750 was the highest.