"best" 2F (1 Viewer)

Mace

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I have been searching for the last hour to see what the main differences between 2F's...

So far I have come up with 86 and newer have "lightened" pieces and are flat tops.

79 and newer have holes drilled in the block for PS.



Other than that, That is about all the info I have found...


Is there any reason to use a 79-85 2f over a 78 2F?

This would be for a high performance application (I am working on actually building a 2F for the turbo instead of letting the old ass mot r I have get a flogging ;) )
 
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correct me if im wrong but you can put tune port injection on the newer 2fs . Right?
 

Mace

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You can put tuned port injection on anything if you want to..
 
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the top part of the motor is swappable or something with later model tune port injection 2fs. thats what i was talking about... i did not know you could put multiport on anything...

i don't mean to highjack but, how? I always like to learn something new! lol
 

Mace

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You can bolt a 3fe head onto a 2F block.. That is easy. However, if you want to make your own manifold you can use the or 2F head and have multipoint ignition..

It is a PITA tho..
 

Cruiserdrew

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Actually the "lightened valve train happened before 85, maybe 81? This is one of those questions for Mark W or Jim C. I'm not sure that makes the motor better. My seat of the pants observation is that a later 2F is better on the highway and the earlier 2f has better low end grunt. It could just be my particular examples though.
 

65swb45

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Jason, fwiw I've noticed that the 2Fs in the 81 up motors have better 'balancing' [and I use that term loosely] from the factory than the 80 and older. Therefore, they should hold up a little better at the higher rpms you're contemplating with the turbo.

Of the 75-80 models, compression is higher in the 75 and 76 models, which have pistons which are slightly domed.

Hth

:)
 
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'75-'80 all have domed pistons to work with the open chambers ('74 and even '73 do to for that matter). '81 and up had flat tops and closed chambers (NA anyway).

Rods are a little lighter in the 81 and up motors.

Valvetrain was lightened in '80 or '81, (I forget right now).

Jim (and others) say that the ports in the later head are more efficient. Personally I have never been able to descern the difference.

I have often heard that the '81 and up 2F has higher compression. I've never seen this in print however and I've never detected a difference in cranking oressure (Factory spec for nominal and minimum cranking oressure is also identical...)

The later heads are a lighter casting and more likely to crack if severely overheated.

Oil pump was inproved in late '77. This pump can be retrofitted to an earlier 2F however.



Mark...
 
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When rebuilding the fj40 82 2f I noticed that the crank is different compared from one I had lying around that came out of a 82 fj60. I'm not sure if the 82 fj40 has the original engine for that matter. Long story short, is that the "balancing" that you are talking about?

65swb45 said:
Jason, fwiw I've noticed that the 2Fs in the 81 up motors have better 'balancing' [and I use that term loosely] from the factory than the 80 and older. Therefore, they should hold up a little better at the higher rpms you're contemplating with the turbo.

Of the 75-80 models, compression is higher in the 75 and 76 models, which have pistons which are slightly domed.

Hth

:)
 
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Mark Whatley! Thanks for chiming in...at one point you pointed me to PacLift for 2F rebuild kits...As far as I can tell they're no longer really doing this. Do you have a good alterna-supplier these days?

thanks, alan


Mark W said:
'75-'80 all have domed pistons to work with the open chambers ('74 and even '73 do to for that matter). '81 and up had flat tops and closed chambers (NA anyway).

Rods are a little lighter in the 81 and up motors.

Valvetrain was lightened in '80 or '81, (I forget right now).

Jim (and others) say that the ports in the later head are more efficient. Personally I have never been able to descern the difference.

I have often heard that the '81 and up 2F has higher compression. I've never seen this in print however and I've never detected a difference in cranking oressure (Factory spec for nominal and minimum cranking oressure is also identical...)

The later heads are a lighter casting and more likely to crack if severely overheated.

Oil pump was inproved in late '77. This pump can be retrofitted to an earlier 2F however.



Mark...
 

Mace

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What is the benefit of closed chambers and flat top pistons?

More room for larger valve opening?

The old motor I had in the 79 spun way easier than the current motor I have in it (no freaking clue other than it is a 2F with holes drilled in the block) I'll get the numbers off of the blocks that I have around.


Sooooo, would a 79 head on a 84 block be the best? Or are the heads different enough that they don't swap easily. I can see the flat top pistons lowering the effective compression if you use a head that is designed for dome top pistons...

Although, what would happen if you ran the domed pistons with a flat top head????

Thanks for the info guys.

And yes, this motor will get flat abused. I am looking at well over 200hp at the rear wheels...

And a 6500K redline..

So, every little bit of work will help ;)
 
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fjwagon said:
When rebuilding the fj40 82 2f I noticed that the crank is different compared from one I had lying around that came out of a 82 fj60. I'm not sure if the 82 fj40 has the original engine for that matter. Long story short, is that the "balancing" that you are talking about?


The later 2Fs ('85 and up IIRC) use separate thrust "washers" on 3# main. The earlier ones used an integrated thrust bearing (flanged)

The balancing that is mentioned is just that. Making sure that all of the rotating components are the saem weight. The later engines seem to hold to a closer tolorance on this. But it is simple enough to match everything yourself. Toyota never attempted to match it all perfectly. You can (and should) while you have it all apart.


Mark...
 
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Chef said:
Mark Whatley! Thanks for chiming in...at one point you pointed me to PacLift for 2F rebuild kits...As far as I can tell they're no longer really doing this. Do you have a good alterna-supplier these days?

thanks, alan


The guy who used to answer the phones and seemingly run the whole operation (Al) retired. He waqs replaced by some young yuppie punk who would not anwer or even return phone calls. My last contact with them was quite a while back. I was waiting on 2 full rebuild "kits". First time I dealt with the "punk". The kits never showd up. I spent days leaving messages on his answering machine, voice mail and all the other fronts he set up to avoid talking to me. I ended it all be telling him that I had an additional five kits I needed immediately but that I'd have to turn else where if we hear from him ASAP and didn't get the two already ordered in hand. Needless to say he didn't return that call either. I don't know what happened with Pac-lift or how they do business now. But it was definitely a sad day when Al retired.


Mark...
 
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Mace said:
What is the benefit of closed chambers and flat top pistons?

More room for larger valve opening?

The old motor I had in the 79 spun way easier than the current motor I have in it (no freaking clue other than it is a 2F with holes drilled in the block) I'll get the numbers off of the blocks that I have around.


Sooooo, would a 79 head on a 84 block be the best? Or are the heads different enough that they don't swap easily. I can see the flat top pistons lowering the effective compression if you use a head that is designed for dome top pistons...

Although, what would happen if you ran the domed pistons with a flat top head????

Thanks for the info guys.

And yes, this motor will get flat abused. I am looking at well over 200hp at the rear wheels...

And a 6500K redline..

So, every little bit of work will help ;)


Flat top pistons with closed (quench) chamber heads is a more effecient setup that domes and open chamber heads for the type of rpm and flow rates that you will see in a 2F. Any 2F.
If you run flat tops in the open chamber head, compression drops a lot. Bad thing. If you run domes in the closed chamber head, the piston and the head try to occupy the same space at TDC. Worse thing.

If you want to run the earlier head, mill it to reduce the volume of the chamber to bring compression back up some. In the real world (as opposed to the dyno) you will never notice an difference in power or economy over the later head with this approach. But if you start with the later head and mill it too, you can attain higher compression.

200+ horses at the flywheel sould be easy. Depending on how much gearbox and such you have bolted behind it you may have to make a lot more to see that at the rear wheels.

6500 would make me very uncomfortable without upgraded rod bolts. I'm eyballing a set of Chevy Bigblock bolts that look like a nice mod that will solve this weak point. (or at least push the worry point a little higher and shift the concern to a different component.)


Mark...
 

Mace

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So basically, an 84 or 85 block has the best of all worlds in a 2F.

The compression ratio does not worry me particularly due to the turbo, But that is excellent info to have.

I already have over 140 hp at the rear wheels (sm420/dual mini tcases/and a 14 bolt), and that is a Stock motor with over 150K on the ticker. I am thinking that a healthy cam and good balancing will let me get up to the 200 RWHP numbers.

Which bigblock bolts are you eyeing???



BTW, It sounds like a 76 2F block would NOT work with a later 3fe head due to the flat top/dome pistons correct?

BTW, as I assemble this motor I will document it and the Dyno results afterwards....
 
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So Mark, are you just buying psitons and rings and cams etc at Napa as needed?
Northern has "kits," but they're way more than what PacLift used to charge...
 
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If you're going to build it for a turbo and high RPM, here's an idea:

3F short block, early 2F head ported/polished. The shorter throw should help the high-rpm abilities of the engine, and the lower compression would let you up the boost considerably.
 

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