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i am also very interested in this idea.

a few weeks back i had a discussion with blind_freddie about creating a f2 DOHC.

i was contemplating purchasing a complete brand new, unused, strengthened f2t bottom end (from a friend), and mating it to an fe dohc head.

from what we discussed, the "oil passage myth" can be relatively easily fixed, by simply blocking up the odd one.

another issue (pretty much the factor that turns me off the whole f2 dohc idea) is compression. somebody suggested that with the fe head on the f2 block, compression would drop to around about 5.1:1.. any thoughts on this?

i think this is a really interesting topic guys and id love some thoughts on it..
 
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XsKaPe said:
i am also very interested in this idea.

a few weeks back i had a discussion with blind_freddie about creating a f2 DOHC.

i was contemplating purchasing a complete brand new, unused, strengthened f2t bottom end (from a friend), and mating it to an fe dohc head.

from what we discussed, the "oil passage myth" can be relatively easily fixed, by simply blocking up the odd one.

another issue (pretty much the factor that turns me off the whole f2 dohc idea) is compression. somebody suggested that with the fe head on the f2 block, compression would drop to around about 5.1:1.. any thoughts on this?

i think this is a really interesting topic guys and id love some thoughts on it..
FE-DOHC has a open chambered head. F2T has a closed chamber head. You'll need domed pistons to make up the compression difference.

You could block off the oil passage, and run it using an externally tapped line to prevent oil pooling.

But wouldnt you want the machined in oil squirters in the block, and not having to use the ghettofied oil passage fix? Also, good luck finding a FE-DOHC head without the engine.

Veltpak hit it right on.
 

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I believe the point has been missed again.

The discussion is about putting a F2T crank in a FE DOHC block. Not putting a FE head on a F2 block.

And if this is what we ARE talking about, then it is a "FE stroker".
 

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It finally clicked in my ape like brain.

Sounds good, though you just lose some of the revving ability which seems to be why people want the FE DOHC. The L20 nissan motor (while being a SOHC 8V ) was a prime example of a stroked motor that couldn't rev anything like it's shorter stroked brother, the L18. Admittedly, most people jumped on the cc train.

remember horsepower is only an calculated figure, torque is where it's at.........well....untill you run out off gears at around 160/170 km/h.
 

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I cant say i have any plans of doing this,but i find the idea quite interesting.

As i see it, its 2 ways too make it happen.
either with custom (146mm rods) and stock FE DOCH pistons.
Drawback in this case are the rod to stroke ratio (1,55)
and it does not leave much room for 87mm+ overbore

With stock rods and pistons with 4 mm lower compression heigth the rod to stroke ratio would be 1,6 wich still are a bit low.
in this case i must ask:
does H23,RSX or SR 20 DET pistons really have the same valve recesses as the FE DOCH pistons? (placement,size,angle and depth)

I guess custom made pistons would be the best option
to get the best rod to stroke ratio and get correct valve recesses
and of course too make a 88mm bore possible (2285ccm)
coating too reduse piston scuffing migth also be a good idea'

Really looking forward too see Randy S results of his prosject
 

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LS VTEC does the same thing. the oil lines don't match up and there aint enouph oil coming from the b18 block to supply the vtec head so they run an external oil line which goes to the oil pressure sending unit which then get's plugged into the head. from what i have seen externally from the fe head and the f2 block it could be posssible . but this has also been done b4 and the engine grenaded. so who ever tries it good luck
 

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point is also missed with Fe and F2 crank........ F2 is 14mm taller to accomidate the stroke

the F2T-DOHC been doen before, and besides custom timing belt tentioner there were no hatles.
 

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Blind Freddie said:
the F2T-DOHC been doen before, and besides custom timing belt tentioner there were no hatles.

Can you go into more detail?

Are you talking about putting the FE head on the F2T block?

Because if so, you just use a Supra timing belt and change your cam sprockets to F2 ones. As you should know that the timing belts have different teeth profiles.
 

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Blind Freddie said:
point is also missed with Fe and F2 crank........ F2 is 14mm taller to accomidate the stroke

the F2T-DOHC been doen before, and besides custom timing belt tentioner there were no hatles.
well the F2-DOHC that was built before byt Jay B was alleged. He told me they used the F2 block/rods/crank and just put a DOHC head and custom pistons in it. Besides the oil buildup in the head it was "OK" power-wise. He said that the guy he sold it too was hyped up about the FE3 revving to 8500RPM and tried that with the hybrid F2-D. Threw a rod. Which is believable because the F2 rods are weaker than the FE3 rods, it was just a matter of time..... or was it???? What doesnt add up about that story is that this was way before Jay did the upgraded valve springs and when everyone still thought the stock dual valve springs could go to 8500 with no prob. when in reality they can barely pass 7k, so how did HE rev up to 8500 then? Jay just upgraded his valve springs shortly before the whole dram`a thing. He told me this story like years ago. Bah well, about a week ago I talked to him and he said he was going for a stroker FE (2.4L) with mostly custom parts. XO


In terms of using H23A/SR20DET/KA20 pistons in a stroker FE3, the valve pockets shouldnt be much of a problem (if they dont coincidentally line up), seeing as how the only real time they'll come in handy is when the timing belt breaks. But, of course, custom pistons would be the obvious choice, just for some, that expense can deter people from even trying the project. Regardless of the chamber design, the pistons will need to be dished... moreso than the FE at a similar comp ratio because of the higher cylinder displacement. 546cc's a cyl (in the 2.2DOHC) would require a 54.6cc total combustion chamber volume to make a 10:1 ratio; whereas it takes only a 49.9cc total chamber vol. to make 10:1 on the FE. If memory serves me correct, the head side of the DOHC CC is 50cc.

We should make this happen!
 

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cam22t said:
Can you go into more detail?

Are you talking about putting the FE head on the F2T block?

Because if so, you just use a Supra timing belt and change your cam sprockets to F2 ones. As you should know that the timing belts have different teeth profiles.
from memory. the timing belt was from some kind of merc or porche. the rods and pistons were custom. crank F2T. the drain holes were filled and FE head main hole got machined for a bit of more flow. when the galleries were filled it was taken great care to make sure that the oil will not collect over them. custom belt tentioner was employed.

custom manifold with real HYBRID turbo (ended up around GT40 size), external turbo oil feed and tank.

all of that went into a Volga(russian make) and to say the least was performing well into 7500 RPM. the turbo blew before the engine..... last i heard of the car it had 120K on the clock and engine was still fantastic.

its not a simple conversion, it took a guy almost 2 years to build the engine, but its not impossible. you just really got to know what you are doing and use correct parts.
 

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Freddie, i had the thing bolted together as a dummy setup.

The timing belt only needed to be longer. Plus because the head was being fitted onto the F2T block, the cam sprokets were changed with F2 ones and i had to source a Supra timing belt.
No tensioner mod required...

In the end i reassembled the FE back together and decided not to bother with the F2(block) FE(head ) combo.

The engine is a great package as is (86x86, square engine).

But i am also tempted in the FE stroker hybrid. I just dont want to lower the redline of the engine.
 

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me and veltpak went through the internet one night looking at any and all pistons we could find. We couldn't find an off teh shelf piston for any of the makes he mentioned for less than having venolia custom make them. It's simple, when you send them the specs sheet, just have them put the wrist pin 4mm higher than stock...

This is the route I'm taking, and if anyone else wants to do it too in the near futre, we can have 2 sets made at the same time for a slight discount...(cheaper for a V8 set than 2 4cyl sets...)
 

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BUMP @-
 

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well, this thread just DIED!!!


Anyways,

cam22t I don't think you'll have to worry about a short redline...I am fully planning on revving my 2.2 DOHC up to 8500 rpms...the rods are plenty strong, and the stroke isn't THAT much...yes longer than most 4 cyls, BUT shorter than quite a few race V8s back in the day. In fact I read about a 302 ford stroked to 331 just last night that was revving above 6500 rpms with a 3.85" stroke (but remember there's twice as many pistons as us, and each piston is bigger in diameter)

It was an expensive engine (at 14k USD) but all the money was put in the heads and intakes to make them rev (which our heads are already set up for-at least the FE3 heads)

But in dyno tuning the motor, they hit a peak HP of 505 @ ~6200 rpms, and set a bnechmakr for a streetable engine (according to the article, and the shop) by creating 1.53hp per cubic inch (N/A)
at the same CR (10:1), the FE3 almost does that from the factory ( 122 * 1.53 = 186hp) either way, it looks like I'm being the pioneer here, but I don't see why I wouldn't get this motor up to 8500 reliably-but it also wont be in my daily driver, so I can't test the relibility factor too much...
Matt
 

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matt...but how long is it gonna last for...?
 

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pioneering

matt89glturbo said:
I am fully planning on revving my 2.2 DOHC up to 8500 rpms...
Good luck and tell us when you've conquered it! I'll be the first to applaud. In the meantime ....


matt89glturbo said:
it looks like I'm being the pioneer here
When it's done, maybe you'll be a pioneer.

When you talk about doing it, you've got plenty of company.
 
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