3FE 9.1:1 c/r pistons ?????? (1 Viewer)

[tntoyota]

3FE 9.1:1 c/r pistons

I hate to drag this up.

Resurching verious motor threads I think I have found that no one has mentioned that the beloved 3fe only has a 8.1:1 c/r or compression ratio

are there any 9.1:1 cr pistons availible?

would this be a cheap and easy fix, and get the 3fe in the ball park of modern motors?


Main's shmain's it will live with this c/r.

It should also still run on low test.

Any one running any thing like this?

I have searched to no evale

Any thoughts?

 

[dd113]

The migthy 3FE is what it is. No aftm hi compression pistons that I have seen but there are total seal rings out there.

It actually is a fantastic motor and the culmanation of 40+ years of work.

 

[tntoyota]

The migthy 3FE is what it is. No aftm hi compression pistons that I have seen but there are total seal rings out there.

It actually is a fantastic motor and the culmanation of 40+ years of work.

I totaly agree.............and dont mind (drive it like a Diesel)

But......


is 9.1:1 high compression?

 

[matt60/80]

I'm looking at Man-a-Fre's website right now and they have high compression pistions for the 3F @ 9.2:1. Man they are pricey.

 

[tntoyota]

THX


http://www.man-a-fre.com/parts_accessories/pistons.htm


TG it's not a V8!


Ahhh........to 2fe or not 2fe that is the question.


My 22r/e is 9.3:1 and runs on low test?

My 3vz is 9.0:1 and runs on low toast?


I think there FOS, and no performance figures?


How many year's they been sellin this?

 

[extremetoy1]

THX


http://www.man-a-fre.com/parts_accessories/pistons.htm


TG it's not a V8!


Ahhh........to 2fe or not 2fe that is the question.


My 22r/e is 9.3:1 and runs on low test?

My 3vz is 9.0:1 and runs on low toast?


I think there FOS, and no performance figures?


How many year's they been sellin this?

Why would you "2FE"


it is a 3FE

 

[Mark W]

The 3Fe has 8.5:1 compre4ssion IIRC. If you want more, just cut the head a little bit.


Why 2FE?

Bit more displacement (not much). More compression. longer rods which equal more torque from the same amount of down force on the piston. Same if not higher rpm limits right out of th box, and; the limit of the 2F is the rod bolts... these can be upgraded... Limiting factor for the 3FE is the side loading on the piston skirts which drop below the shortened cylinder bore. Nothing can be done about this).


Mark...

 

[Moby]

The 3Fe has 8.5:1 compre4ssion IIRC. If you want more, just cut the head a little bit.


Why 2FE?

Bit more displacement (not much). More compression. longer rods which equal more torque from the same amount of down force on the piston. Same if not higher rpm limits right out of th box, and; the limit of the 2F is the rod bolts... these can be upgraded... Limiting factor for the 3FE is the side loading on the piston skirts which drop below the shortened cylinder bore. Nothing can be done about this).


Mark...

I made up my mind on this last week - 2FE for my FJ-62. My new (84) block is at the machinist right now. The real deciding factor for me was the rod ratio. 1.56 in the 3FE vs 1.88 in the 2F. The extra cubes are also nice - every little bit counts

 

[tntoyota]

Acording to Chilton

the 3fe has a c/r of 8.1:1 very low to me, yes it will run on water with that but I guess our fuel is of better quality hence:

22r/e 9.3:1
3fz 9.0:1

2MK, the c/r dictates the octane of fuel?

Moby, don't you mean stroke?

Lot's of stroke is good if you have an OverDrive.

 

[Mark W]

Don't ever use Chilton's for accurate info. Odds are a best 50/50 of it being right.

In this case I don't think it is. Not according to Toyota pubs I have seen.


Mark...

 

[tntoyota]

Please dont take this wrong 1: I have tried and tried but I cannot seem to find any better info.

2: Please dont take this wrong but, prove it

3: I agree with you about taking stock in any publication but I have found "Chilton's" way better than some others.................i.e, "Hayes"

Like I said please don't take that remark wrong

I just consulted the, all knowing, mother of all Toyota books, and literature the one the only..............."Toyota Truck and LandCruiser owners bible" and................


Just like any other specifics...................Nothing

I only bought that book to see the gear ratio's of Toyota transmissions.

What a waste.

 

[dallen341]

The migthy 3FE is what it is. No aftm hi compression pistons that I have seen but there are total seal rings out there.

It actually is a fantastic motor and the culmanation of 40+ years of work.

dd113,

I've seen a few posts where you have alluded to a handful of tweaks that can be done to the 3FE to enhance eprformance. I've searched, but to no avail. Care to share?

Thanks...Don

 

[tntoyota]

dd113,

I've seen a few posts where you have alluded to a handful of tweaks that can be done to the 3FE to enhance eprformance. I've searched, but to no avail. Care to share?

Thanks...Don

crikets churping.......................shhh, be vewy, vewy kwiet

 

[matt.mcinnes]

I made up my mind on this last week - 2FE for my FJ-62. My new (84) block is at the machinist right now. The real deciding factor for me was the rod ratio. 1.56 in the 3FE vs 1.88 in the 2F. The extra cubes are also nice - every little bit counts

I agree every bit helps,

Larger flat faced Valves from Ferrea with a port and polish will increase air flow from 250cfm to 350cfm as well as increase the compression ratio over stock dished valves.

Better pistons from JE Part No 170771 will require a re bore giving you an extra few cc's. Con rods to suit the new pistons will be required.

Plenty more in the link in my Sig The Mule

 

[jonheld]

Same if not higher rpm limits right out of th box

2 or 3 years ago at CMCC, Jim Chenowith was giving a lecture on the RPM limitations of a 2F vs a 3F (amongst 100 other subjects). IIRC the 2F suffered from oil starvation at higher RPMs and the 3FE did not.

 

[matt.mcinnes]

2 or 3 years ago at CMCC, Jim Chenowith was giving a lecture on the RPM limitations of a 2F vs a 3F (amongst 100 other subjects). IIRC the 2F suffered from oil starvation at higher RPMs and the 3FE did not.

I would agree and oiling mods are very much on the cards

 

[Mark W]

2 or 3 years ago at CMCC, Jim Chenowith was giving a lecture on the RPM limitations of a 2F vs a 3F (amongst 100 other subjects). IIRC the 2F suffered from oil starvation at higher RPMs and the 3FE did not.

I don't see any reason that the oilin should be different between a late model 2F and a 3F. Same pump, same passages, same clearances. Different bearing sizes, so that may make a bit of difference. But the real problem in the two engines, respectively, is the rod bolts and the short rod/piston/bore. Both of these will be the failure point before oiling assuming that all systems are in nominal condition. And the rod bolts cane be addressed. The rod/piston/bore relationship can not.


Mark...

 

[agent orange]

Is the problem just that the bore is short? I ask because the 3f rod is longer than a stock 350 rod and you can spin a 350 with a 5.7 rod all day long. The stroke is similar too.

 

[Moby]

Is the problem just that the bore is short? I ask because the 3f rod is longer than a stock 350 rod and you can spin a 350 with a 5.7 rod all day long. The stroke is similar too.

I'm pretty sure that stock 350s have a shorter stroke than the 3F/3FE (I think ~3.5"? vs. the 3F's 3.75"). 3F's have a rod/stroke ratio of about 1.56. The 350 is around ~1.6 if I remember correctly (which I may not be). Both of these are on what is considered the "short" side. But the 3f, with a shorter rod/stroke ratio and a longer stroke than the 350 is at more of at least a theoretical disadvantage when the rpms climb.

What a shorter rod/stroke ratio gives you is higher peak loads. The piston is accelerating and decelerating at BTC/TDC faster than with a longer ratio. As Mark has commented on in other theads the piston also tends to rock more in the cylinder which, especially with the shorter piston of the 3F, leads to higher loads on both the piston and the cylinder wall.

When I was looking at stroking a 3FE (yeah I gave that up quick ) I looked at a lot of rebuild kits and stroker combos in other engine types to see what people were building. There's almost nothing below a rod/stroke ratio of 1.55 and 1.5 is about the minimum you'll find. I also noticed that even with the stock stroke there are 350 rebuild packages with longer than stock rods (6" seems common) which tells me that people are looking to build "longer" rod/stroke ratio in 350s.

 

[pappy]

Don't ever use Chilton's for accurate info. Odds are a best 50/50 of it being right.

In this case I don't think it is. Not according to Toyota pubs I have seen.


Mark...

Mark,

This is from the New Car Features publication from Toyota.