Mazda FE/FET/F2/F2T Tech - Mazda MX-6 Forum
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post #1 of 29 (permalink) Old 11-11-12, 0:22 Thread Starter
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Mazda FE/FET/F2/F2T Tech

Hello. I've been puttering with cars for a few years now, and have recently purchaced a 1991 Mazda B-2200 pickup w/ Automatic. After some gruelling searces, I've found some scant bit of information on performance combinations which seem to be fairly simple and common. Unfortunately, this is very widely scattered. I would like to verify what I've found, and what you all have tried (sucessfully, and not-so-sucessfully), so that I (and others) might have a solid, detailed Technical Reference on these engines.

Now, for the Basics:

FE: 2.0 L, 86mm Bore, 86 mm Stroke, Non-Interference, Timing Belt, 8 Valve head, 35.5 mm Piston Compression Height, 152 mm Connecting Rod Length, Dished Piston Crown (unknown cc's), shorter Deck Height, unknown Cylinder Head Chamber cc's, unknown Valve Diameters and/or materials, Oil restriction made into Head Gasket.

advertised compression ratio ~ 8.6:1

FET: Same as above, except for different pistons and/or head chamber to give advertised compression ratio of ~7.6:1. Non-Intercooled Turbocharger with ~ 7psi boost, Fuel Injection.

F2: Stroked FE; 2.2 L, 86mm Bore, 94 mm Stroke, Interference, Timing Belt, 8 Valve head or 12 Valve Head, Heads Different between FWD & RWD Applications, ~37 mm Piston Compression Height, 158 mm Connecting Rod Length, Dished Piston Crown (unknown cc's), taller Deck Height, unknown Cylinder Head Chamber cc's, unknown Valve Diameters and/or materials, Oil restriction made into Block.

F2T: Same as above, except for different pistons and/or head chamber to give advertised compression ratio of ~7.8:1. Possible HD Valves; Intercooled Turbocharger; 12 Valve heads.

Now that you've managed to get through the infamous wall of text, let me explain why I've been looking for this type of obscure data, and what my goal is.

First, I want to be able to make reasonably accurate calculations of static compression ratio, dynamic compression ratios, rod length to stroke ratio, and piston dwell, etc.

Secondly, I want the information to be available for other would-be experimental tuners.

My specific goal (aka, what I am building for), is a radically fuel eficient, carbureted engine build combination (ie, 35-65 mpg city, higher highway), which can be assembled with mostly stock components, and can achieve high daily-driver reliabilty.

I have read of one approach involving HOT fuel induction and a very mild compressed/homogenized induction system (search for Henry 'Smokey' Yunik's 'Adiabatic Engine')


What type of build I am considering is as follows:

F2T Short block, with NA (High Compression) pistons, the higher the better (stock pistons, not aftermarket). This will seem to go against the grain, for typical detonation/turbo compression 'rules of thumb'.

F2 8 Valve Head (B-2200) for stock distributor location, etc. Possibly FET Head, if same distributor location/layout (I haven't found any information as to those details), and possible use of FET Cam/Valves for Turbo-Optimized Valve Timing/Valves/Camshaft.

At this point, I have a NA engine with provisions for oiling a turbocharger, which doesn't have to be used, I could bypass/plug the oil passages, and just run NA with no ill effects.

Should I decide that a Turbo is worthwile, I would swap the NA F2 exhaust for the FET Exhaust manifold/turbo assembly, and fabricate the necessary exhaust plumbing to the tail-pipe as necessary. This would also involve re-working the intake side, likely by removeing the Carburetor and placing it upstream of the Turbo (ie, Draw-Through setup).

To avoid detonation, I would switch to a homogenous Hot Fuel induction, and possibly alternative fuels exclusively (ie, propane, cng, or E-85), to better optimzed for efficiency.

My eventual goals is for a low-end torque build, with early rpm, low-boost (ie, less than 15 psi), on a static CR of ~ 9.5:1 (or what can be achieved by the best HC Piston Combination), resulting in a Dynamic CR of ~ 14:1-16:1, ideal for ethanol's ~ 106 octane properties, and well suited to the anti-knock of internal evaporative cooling (ie, water injection into the intake charge)

Ethanol is also ideally suited for vapor-phase mixing, due to the fact that it boils before 175 degrees F, which is very cool for a thermostat around here.


I would like to see something along the order of ~135 hp, and ~ 35 mpg city, 55 mpg highway, on E-85 (Ethanol, or Moon-Shine LOL). If 85 octane regular with also work, with the same mpg, so much the better.

Please feel free to share any Information & Experience that you might have.

Thank You.
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post #2 of 29 (permalink) Old 11-12-12, 4:29

 
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You'll never get those MPG figures on E85 unless its a motorbike.

typical A/F is between 7:1 and 9:1 for E85.

You might be able to achieve those figures with a direct injection turbo diesel!

84 626 sedan FE SOHC turbo, FE3 on hold, Toyota E58 conversion under way - slowly!
84 626 sedan RF diesel, a slug but you get 6.0L/100km (39MPG)
07 Mazda 6 MZR-CD 6sp manual - new DD
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post #3 of 29 (permalink) Old 11-12-12, 23:57 Thread Starter
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I was thinking more along the lines of ~20:1 Gasoline, ~16:1 ethanol. The key is to completley evaporate the fuel prior to mixing with air (catalytic processes optional), thus allowing the normally 'wasted' droplet cores in the air/fuel suspension to contribute to powering the vehicle. I forget the exact term for the effect; the outer layers evaporate, then combustion occurs, which causes the hiigher boiling components to evaporate, and burn - about which time the burning gases are goiing out the tail-pipe, or sitting in the crapolytic converter, and not making your car go (or go faster)

Smokey Yunick was getting crazy power back in the early 80's with a pontiac fiero 4 cylinder (and other engines), while inducting the air/fuel mixture into the cylinders at ~ 425 degrees F, under ~ 1PSI Boost. ~250 HP, 2.5 L, Carbureted, ~50 mpg, anyone?
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post #4 of 29 (permalink) Old 11-13-12, 3:01

 
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You might be thinking about stratified combustion ?

There were a few efforts by various manufacturers to do something with it back in the early 80s when oil prices skyrocketed after the issues in Iran.

But alas the average consumer of cars was more interested in cupholders than fuel economy so the whole thing went onto the back burner by about 1985.

My 626 diesel and the Ford Escort diesels of the same era were thought up thanks to oil prices in the early 80s and there was a reason they were not sold after 1987.

The other issue for the manufacturers: lean mixtures mean high NOx and this was a problem for emissions compliance....but almost no car has any real reduction of NOx only for the emission test!

84 626 sedan FE SOHC turbo, FE3 on hold, Toyota E58 conversion under way - slowly!
84 626 sedan RF diesel, a slug but you get 6.0L/100km (39MPG)
07 Mazda 6 MZR-CD 6sp manual - new DD
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post #5 of 29 (permalink) Old 11-13-12, 9:48 Thread Starter
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I am very specifically thinking of a prototype engine configuration developed by the famous historical racing mechanic during the late 1970's and early 1980's, which was never put into oem production. There are 'secrets' which need to be teased out, but the basic setup is widely available in basic description.
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post #6 of 29 (permalink) Old 11-13-12, 10:27 Thread Starter
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The available, specific details, are as follows:

1.) Remote carburetor, air-cleaner, etc.
2.) Coolant heat-exchanger underneath carburetor, to heat air/fuel mixture to nearly 212 degrees F (or coolant temp)
3.) Draw-Through Turbo (Air/Fuel Mix into Turbo)
Turbo is modified as follows:
A.) Heat-Exchanger from HOT (Exhaust Side) to COOL (Intake Side)
B.) LOW Boost (~ 1 PSI)
4.) Engine Geometry specifically calls for ~ 12-25 degs of piston dwell @ TDC. This translates into a longer R:S Ratio (I don't recall the specifics, but it is described in the patent)

FYI: Patents are good for 20 years, with 1 renewal available, and do not prevent someone from duplication FOR THEIR OWN USE, nor for MAKING IMPROVEMENTS and filing their own patents.

The 'secret' is described as 'simple', and has something to do with the carburetion air/fuel mixture, and the balance of heat flow/temperature ratios in the intake stream.



My theory is that it is something along the lines of the fact that common 'stochiometric ratios' cited include a large portion of un-burned fuel in the 'fuel portion' of the ratio, so the breakdown would be something like this

Fuel = Fuel Burned + Fuel Wasted

Air = Air needed to burn the AVAILABLE FUEL (FUEL Burned - Fuel Wasted

Therefore, by minimizing the 'WASTE' Portion of the introduced Fuel, and Increasing the 'USEFULL' Portion of the Fuel, we get both

BETTER FUEL ECONOMY and MORE POWER

Key thoughts: If 33% of the FUEL introduced into the engine is not able to burn IN THE ENGINE, then it is effectively wasted as it burns IN THE EXHAUST (Catalytic Converter) or NOT AT ALL (HC Emissions). Thus, only enough air is needed to burn the 66% of the FUEL that actually burns in the ENGINE.

If, say, 10% is the WASTE FACTOR, then MORE AIR (Leaner Mixture) is needed, because we are burning 90% of the FUEL in the ENGINE (making power). Correspondingly, we can then reduce the the total ammount of fuel introduced into the charge (ie, smaller injection pulse, smaller jets in carburetor)

The IDEA is to optimize this USEFULL/WASTE Fuel ratio so that 100% of the fuel is USED and 0% is burning outside of the engine or not burning at all.

VAPOROUS Fuel PREMIXED with the AIR in the INTAKE CHARGE does this by making the INTAKE FUEL Completely Available to the Oxygen in the AIR, and prevents DETONATION (in theory) by providing a very even dispersion of the light, medium, heavy fuel molecules and a very even dispersion of the Oxygen in the AIR.
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post #7 of 29 (permalink) Old 11-13-12, 11:00 Thread Starter
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One more insight - The 'LEAN' mixture described above does'nt ACT Lean, because, in fact, it IS NOT 'LEAN', as all availble FUEL can react with all availble OXYGEN'.

The KEY is to think of the ratio as not 'AIR:FUEL'

but as

'AIRUSEABLE FUEL = TOTAL FUEL - UNAVAILABLE FUEL)

or (OXYGEN FRACTION + INERT FRACTION)USEABLE FUEL = TOTAL FUEL - UNAVAILABLE FUEL)

As for NOX, why not use some sort of internal temp control (ie, evaporative cooling) to control the peak combustion temps (main source of NOx)

EGR does this by re-introducing exhaust, thus LEANING the INTAKE CHARGE and RE-Burnign the EXHAUST, resulting in a seemingly paridoxical 'HOT EXHAUST RECIRCULATION = COOLER BURN ?!?!?

but, how does this actually work? (scratches head)

TOTAL EMISSIONS WOULD BE DOWN due to less fuel consumption.
(ie, a car that burns 1 quart of OIL per gallon wouln't put out that much total tonnage if it doesnt drive very far, or can go 600 miles on that 1 gallon)

EXAGERATED TO ILLUSTRATE PRINCIPLE


But, are we concerned about

A.) Making the SMOG BUREACRATS happy (even though most don't even know how to change thier own OIL or how to use a BOX END WRENCH, much less the actual physics/chemistry involved, or the empirical KNOWLEDGE of what happens based on good old fassioned trial and error (or those who win on race day know more of what works than those who don't)

B.) Having gobs of power to go and play with (and the corrosponding satisfaction of watching someone cry because they think their brand new corvete/mustang/porsche/fiat/etc is a DOG because they just got beat or passed by a mid-80s hyudai, toyota, chevrolet, ford, crysler, (or mazda)

C.) Being able to AFFORD to still drive when fuel hits $20.00+ per GALLON in the US in 2016 (not sure of other areas) All of the new car manufactures are beating thier chest about 40 mpg here; 1989 Metro with 100K+ Miles will get 50 mpg, and the GUINEAS WORLD RECORD IS 900+ MPG.

I think that the energy is there to get to ~ 70 MPG per US Gallon, if PROPERLY UTILIZED, and CONSERATIVLY APPLIED and FRUGALLY MANAGED (ie, regen brakes, utilizing waste exhaust heat, getting low rolling restance tires, aerodynamic optimization, taller gear ratios, manual gear box, et.)

Pick your poison
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post #8 of 29 (permalink) Old 11-13-12, 12:00

 
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Use hydrogen (w) gasonline. Mixing the 2 (hydrogen Hybrid) increases the flash point inside the combustion chamber which results in cleaner combustion and a instant mpg increase. Simple n easy. And you can make a HHO Generator with crap from your local hardware store.
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I think this is probably one of the coolest new threads ive seen on this site in quite awhile. Ive always been a big fan of Smokey Yuniks Fiero projects. Ive read probably 5 different magazine articles covering it over the years and have even researched online myself in the past. I cant wait to see the outcome from this.

~Patrick~

http://www.pmx626.com/ Your all in one Probe, MX-6, 626 Search engine.
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post #10 of 29 (permalink) Old 11-14-12, 6:47 Thread Starter
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A little more Tech (Specific to FE/FET/F2/F2T Engines)

I find Piston Compression Height for the FE to be 35.5 mm / 1.397"
Rod Length is 152 mm / 5.985 "
Calculated Deck Height with Zero Clearance is 230.5 mm
(Center of Crank to Top of Piston)

I find Piston Compression Height for the F2 to be 37.0 mm / 1.450"
Rod Length is 158 mm / 6.220 "
Calculated Deck Height with Zero Clearance is 241.5 mm
(Center of Crank to Top of Piston)

FE Pistons in F2 Block will effectively increase deck clearance by ~ 1.5 mm / 0.060"
This is about the same as increasing piston dish by about 8.7 cc, giving
a Static Compression Ratio of about 7.6:1

If anyone has actual measurements of Deck Height or Compression Height for either engine, feel free to confirm or correct.

FYI, on Yunick's layout, the patent mentions Piston Dwell within 0.001" for ~ 13 degrees (6.5 BTDC to 6.5 ATDC).

FE is about 0.0180" for 14 degs (7 BTDC to 7 ATDC)
FE is about 0.0197" for 14 degs (7 BTDC to 7 ATDC)
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post #11 of 29 (permalink) Old 11-17-12, 5:11
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Quote:
Originally Posted by jmuse8482 View Post
Use hydrogen (w) gasonline. Mixing the 2 (hydrogen Hybrid) increases the flash point inside the combustion chamber which results in cleaner combustion and a instant mpg increase. Simple n easy. And you can make a HHO Generator with crap from your local hardware store.
Here's something to study before subscribing to the HHO idea:

Hydrogen Boosting explained

The general principle is that whenever your alternator sees load, your mileage goes down, regardless of the supposed purpose of the load. That's the unfortunate nature of thermodynamics.

1988 626 Wagon GT 2.0 DOHC Turbo | 1988 626 Hatch GT 2.0 DOHC | 1992 Toyota Carina e GLi | 1991 626 GLX Hatch AWD 2.2 l 1998 Volvo 940 STW Turbo Classic | 1988 626 Coupe GT 2.0 DOHC

My vBGarage My ride at CarDomain


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I think its more the law of no free lunches.

The theory behind EGR on a gasser is to fill the combustion chamber with an unburnable gas, essentially just a filler gas, which cools the charge a little and reduces NOx (in theory) but the main reason for doing it is to reduce the engine's capacity without introducing more manifold vacuum which ruins efficiency.

On a diesel, where most engines dont have a throttle plate (though some do through quirks of emission control systems) EGR is meant to lower combustion chamber temps and reduce NOx.
Very few manufacturers have managed any useful reduction in NOx, its all about passing the emissions tests.

The cold hard reality is that higher efficiency usually leads to higher NOx. I don't know too many people who are happy to burn more fuel to lower NOx levels.

I am sure there are many ways of improving mileage, but you the car buying customer didnt have fuel economy high enough on their list of priorities for the manufacturers to give a s**t.

You all wanted SUVs weighing 2+ tonnes with 50 squillion airbags and god knows what other useless crap the car manufacturers would have you believe you can't do without, and fuel is relatively cheap.....now, and most people dont think ahead further than next week, let alone 10 years from now.

The first thing manufacturers could do is cut weight, this would lead to an instant improvement in mileage.
I can only imagine what sort of mileage I might get from my 2200lb 1984 626 with a current 2012 engine in it.

84 626 sedan FE SOHC turbo, FE3 on hold, Toyota E58 conversion under way - slowly!
84 626 sedan RF diesel, a slug but you get 6.0L/100km (39MPG)
07 Mazda 6 MZR-CD 6sp manual - new DD
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Just to correct your info in the original post, the f2/f2t are non-interference.

as far as the dwell time, that is changes basically by rod lengths, assuming you keep the stroke the same, correct? If so the easiest way could be an f2 block with the fe crank, then just find the proper combo of rod/piston to take up the space...if the dohc head worked on the f2 block easier, I wanted to build one that way years ago, but I don't think the benefit outweighed the work for it, so voted against it.

IIRC the deck height difference was 14mm from an fe block to the f2, but may just be the fe dohc, which is a different block, and different rod length, but not sure if the block deck heights are the same...but an extended rod with the fe sohc piston should make some good dwell time. You would just need to find/make a piston that fits the same to bump compression
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post #14 of 29 (permalink) Old 11-22-12, 0:55 Thread Starter
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I would have to check. My source had indicated that NONE of the F Engines are an interference fit with the EXCEPTION of the LONG STROKE 2.2.

Mazda 4 cylinder Engine History and Interchangability Guide

I haven't looked up the application in a timing belt catalog (they usually are pretty good about indicating whether the engine is an 'interference' or not.)

Rod Lengths are from Solomiata : Engine : Rod comparison.

I could see a possiblity for a slight increase in rod:stroke ratio by using FE Pistons (shorter CH) and longer rods.

About the highest ratio combo I can think of with mostly stock components would be a de-stroked F2 (using a 77 mm F6 or F8, or the 86 mm FE Crank), the FE Pistons, the tall F2 Block, and custom rods to place the pistons @ stock deck height +/- clearance. More should be possible with aftermarket pistons, or custom machinework.

Conversely, If you want a lower compression ratio, or a lower rod:stroke ratio, the FE Rods in the F2 Block/Pistons/Crank would be the ticket. Thats my theory, anyway.

As for the Deck Height difference, the difference isn't simply the difference in the stroke. It would be the difference in the eccentricity/offset of the crank throw (1/2 stroke) with the difference in the rod length, difference in piston Compression height, and difference in Piston Deck Clearance.

All else remaining the same, going from 86 mm to 94 mm is and increase in 8 mm stroke, or 4 mm eccentricty. thus, the piston will travel 4 mm higher in the bore @ TDC (and the deck height will need to be 4 mm higher to maintain a piston-in-block clearance versus a piston-in-head chamber protrusion).

Add the 6 mm difference from the rods (152 mm FE vs 158 mm F2) gives a total of 10 mm increased deck height for the F2.

Add another ~ 1.5 mm for the difference in Compression Height
(FE is 1.397" /35.5 mm, F2 is 1.450" / ~ 37 mm),

and we get a theoretical difference of 11.5 mm; NOT the often quoted 14 mm difference.

Granted, the manufacturer could do things like off-set the Crank-Shaft Main Bore in the same block, to alter DECK Height (as measured from crankshaft center-line to Head Gasket Surface), but the machining could get hairy.

I know that someone somewhere KNOWS the actual stock measurements, but on-line research finds hen's teeth first.
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post #15 of 29 (permalink) Old 11-22-12, 1:10 Thread Starter
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I know that the specs for the Toyota 20R/22R Early block (Block Deck Height, Head Deck Height, Head Chamber cc's, Rod Length) and Late 22R (Shorter Block Deck Height, Different Head Deck Height) are available online. I haven't found anything like that for the FE/FET/F2/F2T Engines, however. That makes it a little difficult to derive combinations of block, pistons, rods, camshaft, turbos, etc. that will work with each other to give a desired result (such as a LONG STROKE low-revving HIGH COMPRESSION GRUNT MOTOR with very light piston side load and HIGH PISTON DWELL AT TDC, to hopefully survive to 200 K miles on a full overhaul, while getting the best technologically possible fuel mileage.
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