2FE conversion pistons

[MiniPigg]

I dropped the head off at the shop last week. They are finished with it. Ran me 229usd for everything including drilling, tapping, and plugging the oil galley plug.

I am using an 1977 2F short block. Of course it has the dome pistons in it. the block has almost no wear in the cylinders. There is zero groove. Has about 150K on the engine.

Right now my question is which flat top piston is going to work the best with this conversion?

 

[FJ40Jim]

The 2F flattop piston, 81-87 style, is the correct part.

 

[MiniPigg]

The 2F flattop piston, 81-87 style, is the correct part.

When I asked SOR about this they said any of the flat tops would work but would lower the compression ratio?

I can see that if I were to continue to use the 2F head but from what I can see the 3FE head has smaller combustion chambers. If it did lower the compression it couldnt be that much.

Whats your take on this?

 

[Trollhole]

When I asked SOR about this they said any of the flat tops would work but would lower the compression ratio?

I can see that if I were to continue to use the 2F head but from what I can see the 3FE head has smaller combustion chambers. If it did lower the compression it couldnt be that much.

Whats your take on this?

Cannot use domed on a 3fe head. Well it won't work for long.

Go with what Jim has said above. And get your engine rebuilder to source your pistons.

I got mine with rings (ITM) for something like 37 each.

 

[MiniPigg]

Cannot use domed on a 3fe head. Well it won't work for long.

Go with what Jim has said above. And get your engine rebuilder to source your pistons.

I got mine with rings (ITM) for something like 37 each.

yeah.. i know you can not use dome pistons with the 3FE head. Thats why I am asking which flat top piston is the best to use. I figure if I am going to replace them anyway I might as well go with the better flat top piston.

 

[CruisinFJ60]

81-87 2F motor. they can come from the 40's and the 60's of those years.

domed will make contact with valves.

im buildin a 2FE and am gonna go with a .20 over bore as well on mine and possibly a few other goodies.

 

[Trollhole]

yeah.. i know you can not use dome pistons with the 3FE head. Thats why I am asking which flat top piston is the best to use. I figure if I am going to replace them anyway I might as well go with the better flat top piston.

Sorry about that.

Grant told me once that ITM makes a decent piston.



Have heard good things about these. Spendy but nice.

MAF Forged High Compression Pistons

 

[MiniPigg]

Thanks Marshall.....



Anyone know of a good head stud kit for the 2F? As always those head bolts are a pain to get out.

 

[matt.mcinnes]

Thanks Marshall.....



Anyone know of a good head stud kit for the 2F? As always those head bolts are a pain to get out.

One option


IH8MUD.com Forum - View Single Post - 2F + 3F-E = 2F-ETI Into My FJ40

 

[FJ40Jim]

When I asked SOR about this they said any of the flat tops would work but would lower the compression ratio?

Why do I have to explain the maths to people at SOR?

Compression ratio=(Swept volume + chamber volume)/chamber volume

So comparing 3f:
(4.0L +.57L)/ .57=8.0

Substituting the 2F swept volume:
(4.2L + .57L/ .57= 8.4

Putting a 3F head on a larger displacement 2F block will increase CR.

I can see that if I were to continue to use the 2F head but from what I can see the 3FE head has smaller combustion chambers. If it did lower the compression it couldnt be that much.

Whats your take on this?

Don't ask a parts monkey any engine math questions?

 

[FJ40Jim]

yeah.. i know you can not use dome pistons with the 3FE head. Thats why I am asking which flat top piston is the best to use. I figure if I am going to replace them anyway I might as well go with the better flat top piston.

Are you asking which year/model to use?
There is only one design flattop 2F piston, used in all 81-87 2F engines.

As far as recommendations of particular manufacturers, there is one jap mfg, that makes for Toyota and some aftermarket, an american that makes for federal mogul/sealed power, and a taiwanian that makes ITM and other off-brands. They've all worked in engines I've built.

 

[CruisinFJ60]

When I asked SOR about this they said any of the flat tops would work but would lower the compression ratio?

I can see that if I were to continue to use the 2F head but from what I can see the 3FE head has smaller combustion chambers. If it did lower the compression it couldnt be that much.

Whats your take on this?

touching back on this....

with the longer stroke of a 2F compared to a 3FE the piston will move further up and down in the cylinder meaning more displacement. also when using the 3FE head on a 2F since the piston is moving up higher in a 2F block as compared to a 3FE you will get some extra compression just from that now also figure in that the 3FE head has a smaller cc head chamber to make up compression due to a smaller stroke add the 2 together and you get a pretty nice compression boost.

now the domed pistons wont work due to the fact that the piston moves up to high and will make contact with the valves flat tops will not. and if you went with dished pistons you would have a slightly less compression ratio yet again but would also yeild for more duration on a cam (tho long duration is not exactly the most important thing for torque a shorter duration would be better there tho not important in this im only giving options... maybe a 2nd turbo build 2FE.....)

hopefully this will clarify for anyone who was kinda lost (if anyone) just thought i would throw in some infor there.

 

[FJ40Jim]

There is an interference issue, but to clarify further, the domed pistons will hit the head, not the valves. Valves stay in the same relative location in all 2F/3F heads.

 

[MiniPigg]

Jim,

I broke the engine down today. The rod and main bearings look awesome as does the cylinder walls. The engine had great compression to begin with. Being it only had about 150K. The machinists is going to replace the bearings and such with high quality parts. Now that I need to replace the pistons I wanted to ask you another question. I am unsure how many vendors there are that carry the TLC flat top pistons. I am sure most of them are very good quality. But is there a company that you would stay away from? I wanted to ask this because he is going to give me a quote on the set.

Have you ever used the Total Seal piston rings in a 2F?

thanks

 

[FJ40Jim]

As a matter of preference, I like Sealed Power brand. They have been very consistent on weights & sizes.
Hastings Cro-Mo rings have worked well on rebuilt engines. However, since this engine is getting re-ringed in a used bore I recommend a cheap, soft cast-iron ring that will seat easily. A hard ring may never break in to a used bore.

No experience with Total seal.

 

[Pacer]

I/we've had good luck with Total Seal rings in many BMW race engines. I would not steer you away from them, and if you give the bore a light hone the rings will seat nicely. and use conventional oil on your first run.

 

[lehiguy]

The 3F head on a 2F bottom end should run nicely. I milled .070 (that's not a typo) off a 2F head and it ran great, but I rarely go below 4000 feet. It did require premium after that however. I'm curious which cam you're going to run. The old 2F cam part number has been superceded by the 3F cam which has a bit more lobe separation to keep the fuel injection of the 3F happy. The 2F cam makes slightly better bottom end because it has more, well some anyway, valve overlap.

 

[matt.mcinnes]

My 2F-ETI has total seal rings.

Cam specs are

Few more spsecs
Note the combustion chamber was opened up slightly from 79cc

 

[MiniPigg]

Tonkokta brought up the Cam's Mark W. uses from deltacam.com. He said the Mark uses the part number KC859. I called them at was qoute around 74 usd. (Cant remember the exact quote)

They also regrind the lifters for 2usd each. All in all about 135usd with needed repairs to the cam lobes. Im thinking.

The machine shop qouted me 130usd for an ARP head stud kit installed.


Now I need to find a place that sales the flat top piston for a very nice low price.

btw: Any thoughts on also using a crankshaft stud kit for the lower end? Not sure if the cruiser engine needs it and its not like Im going forced induction.

 

[matt.mcinnes]

Tonkokta brought up the Cam's Mark W. uses from deltacam.com. He said the Mark uses the part number KC859. I called them at was qoute around 74 usd. (Cant remember the exact quote)

They also regrind the lifters for 2usd each. All in all about 135usd with needed repairs to the cam lobes. Im thinking.

The machine shop qouted me 130usd for an ARP head stud kit installed.


Now I need to find a place that sales the flat top piston for a very nice low price.

btw: Any thoughts on also using a crankshaft stud kit for the lower end? Not sure if the cruiser engine needs it and its not like Im going forced induction.

My crankshaft studs are pretty stock but as I'm forced induction I had a little extra added