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Discussion Starter · #1 ·
I have a 1991 MX6 LX, and I know that the first gen Ford Probe and mx6 were made in factories together and are nearly mechanically identical. I know the Vulcan V6 was an option in the Ford Probe and I wanted to see if it would work in my MX6 and if so if I had to change out any other parts of the drivetrain.
 

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You would have to use a sight like rockauto to cross reference parts like axles, clutches, starters and motor mounts between it and the F2 probe to see if they match.
The only thing I know about the Vulcan probes (beside the fact the engine sucks like the taurus) is that the final drive in the transmission can be used in the mazda H gearbox (but I think it's shorter, who would want that?) and that we looked at many probe parts cars that claimed to be GT but had the V6, we did buy one from my shop partners brother but it turned out to be a V6 auto. A boat anchor, bolted to a turd, stuffed in a bucket, so we sent to whole thing to the scrap yard where it belonged.

Now I have to ask why?
 

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This should be a fairly straight forward swap, the manual trans is a variant of the f2t trans, so axles and shift rods are the same, if you had the engine, ecu and harness, then the trans, flywheel and clutch, and the right mid shaft that bolts to the block, you have most of the hard parts needed. If doing the auto, you would need to do research on that, as I am not sure what auto trans was used. I think electrically all the connectors might fit, but might need to repin some wires. It has been a long time since I have messed with the v6, though, so might be some of the smaller details I'm forgetting, but in my head it should be easy, especially if you have a donor car with you during the swap.
Left stock, it's a solid engine with OK torque and a broad powerband, doesn't have the "punch" of the turbo GT, but is very smooth at putting down power. Not sure how they are about modifications, but if you decide to go overboard and go for the SHO version, everything I said goes out the window... they don't fit without a LOT of work.
Also FWIW, V6 H box final drive is a 3.85 vs the 4.11, so slightly taller...
 

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Don't do it. The Vulcan is just a cast iron lump. I've owned all 3 variants and the Vulcan was the slowest. My Mx6 F2 auto on "sport" would be way more fun that my auto Vulcan Probe. Obviously the f2t 626 was the fastest of them all.

The F2 has an easy parts list from factory cars and can make easy power with a budget. Don't Vulcan swap!
 

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Discussion Starter · #5 ·
Don't do it. The Vulcan is just a cast iron lump. I've owned all 3 variants and the Vulcan was the slowest. My Mx6 F2 auto on "sport" would be way more fun that my auto Vulcan Probe. Obviously the f2t 626 was the fastest of them all.

The F2 has an easy parts list from factory cars and can make easy power with a budget. Don't Vulcan swap!
I have the Manual, do you think I’d be better off with a turbo f2 engine swap instead of the Vulcan V6?
 

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I have the Manual, do you think I’d be better off with a turbo f2 engine swap instead of the Vulcan V6?
Yes, many times better off. Unless the 3.0l Vulcan V6 has insanely big and strong main caps that are good for lots of boost and no one ever bothered trying.
That is the problem with the 2.5L KL blocks, they are aluminum and only have 4main crank caps which is the perfect recipe for block distortion under heavy boost.

They say there is no replacement for displacement but forced induction is the same as increasing displacement. Your N/A 2.2L engine puts out 110 whp and 130 ft-lbs, that would be about 13.5lbs/min of air, if it was a 4.4L making 220hp and 260 ft-lbs (this is a simple example, drivetrain loss would be a lower percentage but the rotating mass of the engine would be greater) it would consume about 27lbs/min of air. If the 2.2L had a turbo capable of flowing 27lbs/min of air running 1 bar boost and boost air was cooled to the same temp as ambient air, it would be the same as having a 4.4L but with less power loss turning the crank and cam.
But the real difference is that the Naturally aspirated engine will consume 27lbs/min of air where or when it can (this varies depending on stroke, bore, cam, valves, intake runner length and exhaust design).
The forced induction engine is Forced to consume the air that the turbo, supercharger or blower puts out when it puts it out (when sized properly for the engine and goals, with proper sized turbine housing and exhaust), if the turbo forces the engine to consume 27lbs/min of air early in the powerband and continues to do so to redline than the forced induction car will be much faster than the N/A tune that consumes the same amount of peak air but only where it's set up to do so, variable valve timing has helped to compensate for the peak power band limitations of naturally aspirated engines but still doesn't hold a candle to forced induction engines.

So there actually is a replacement for displacement but it comes at a cost, stress, if you double the power you double the heat and pressure on the components, proper oil and engine cooling is required and proper engine components are required (strong pistons, rods and crank) the F2T has all of those, but all the seals must be up to the task of the load the engine will face, 30 year old gaskets and seals won't survive constant load (fast driving) even in stock form.
 

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Depends on your goal. I would say the ONLY reason I would consider swapping is the Vulcan is smoother than the f2, but only if leaving it basically stock after the swap. The only one I drove was a manual, and it was OK. I was surprised it was quicker than I expected. The car had an exhaust on it with a Mangaflow muffler but was otherwise stock with a broken water pump line. Made a close to 100 mile drive home just stopping to let it cool a couple times. I know they had a bad rap for head gaskets, but there were also a lot of these on the road for a lot of years, so might have just been the same ratio, but a lot of people complaining about it. A stock f2t would run circles around it, and raising the boost even more so. Again I know nothing about what auto was used with them, I don't think it was the same mazda box, though, so could have been a bigger power draw than an f2 auto...
Is you're going for power and fun to drive, f2t, mileage, f2, smooth, Vulcan v6
 

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Well I logically assumed that anyone looking to do an engine swap on a 1991mazda mx6 F2 was looking for more power not more smoothness and decided the op probably was looking for the highest displacement/ hp rated option available in variants of the 1st generation probe, I proceeded to attempt to explain the principles of forced induction in the hopes of offering a different option than the Vulcan 3.0l.

The F2T can be as good on gas as the F2 if you can resist the fun to drive part and can be much smoother with the right size turbo (one that doesn't spool at low throttle but doesn't lag at full throttle).

Besides when do you ever floor a car and wish it had a smoother more progressive power band? If your passing a car you want to do it as quickly as possible, if you aren't you want to accelerate and go fast.
 

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Discussion Starter · #9 ·
I was looking for fastest, I was also told the KLDE was an option in some Ford Probes. I found a cheap Ford Probe with a KLDE in it, but the biggest problem for me is going to be getting new parts for the Japanese engines if I run into problems. Is the F2t still the best option with that as well?
 

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I was looking for fastest, I was also told the KLDE was an option in some Ford Probes. I found a cheap Ford Probe with a KLDE in it, but the biggest problem for me is going to be getting new parts for the Japanese engines if I run into problems. Is the F2t still the best option with that as well?
The KLDE is in North American 1993 - 1997 Mazda Mx6 and Ford Probe (next generation), The KLZE is the Japan version with higher comp pistons and better cams. The all aluminum 2.5L Lemon puts out a whopping 168bhp (198bhp for the ZE), they can be temperamental, have constant ignition issues (spark) and don't take well to boost (crank assembly was never designed for the torsion caused by boost).

The F2T and KLDE where never available in japan, Japan cars got the FE3 (2.0L 16v) and KLZE but some F2T probe GT and possibly KLDE probe GT's where sold there (both build in the USA).

If you want to go fast you need lots of displacement or lots of boost or a really light car.
Of all the engines mentioned the F2T has the greatest potential in stock form.
The F2T will hold 30psi boost with water meth injection on stock internals, My 626GT runs 30psi, factory ECU with boost cut removal chip, an extra injector controller, home made water meth system, an 80$ junk yard T3 60trim turbo and a clutch strong enough to hold the torque. This required a 2.5" exhaust system and larger than factory intercooler pipes (both where fabricated out of used exhaust parts and junk, there are a lot of other modifications and upgrades on the car but that is all it took to make it really fast.

With unlimited budget there might be a chance the Vulcan V6 has the highest power potential, that all depends on the main cap design, the fact the block is cast iron helps.

I don't know enough about the V6 3.0L Vulcan to say for sure, Ford north america was not known for building good 4 or 6 cylinder engines back then, if you look at the small displacement ford engines availlable around the world you can clearly see Ford didn't give a shit about it's domestic market for small displacement engines (Pinto vs Cosworth) .

Mechanically the F2T has 7.8:1 compression pistons, the F2 has 8.6:1 compression pistons, the F2T has different exhaust valves (material but same size), They run the same cam, head, intake, throttle body, fuel pump block, crank, rods and bearings...
If you hand sand the combustion chambers from 50cc to 55cc you will have 8.0:1 compression ratio on the F2 block, add engine management and a turbo and make the engine you have really fast.

If you have an F2T parts car than converting everything makes sense but otherwise for the amount of custom work the F2T requires to be fast (turbo, exhaust, intecooler and pipes) you will have swapped out all the turbo parts and just be using the turbo block which is the same as the N/A. Transmission is another story, the F2T transmission requires all three mounts, the entire shift rod assembly, the two plates that sit between the block and transmission, the flywheel and clutch, the slave cylinder, axles, intermediate shaft, front and rear block to transmission mounting brackets and the wheel hubbs + all the different bolts for the GT transmission and parts mentioned.

Don't get attached to a car, love a model of car, shit happens...
Your best option is to buy a 88-92 MX6 GT in good shape for 3000$ or less, pull the engine and clean everything and change every 30+ year old gasket and seal, have the differential housing shaft welded to the differential housing and upgrade the clutch and reinstall. Buy a wideband gauge and oil pressure gauge and start from there.
With a chip at 15psi (boost control and chip = +- 100$) The F2T is fun to drive and will beat STI's, SRT4's and Talon's... It won't be fast or quick but it has the potential to be and you can make it that way one modification at a time while still enjoying the car and learning to deal with or tune around each change.
 

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Discussion Starter · #11 ·
There is someone in my area with a Mazda 626 that they’re selling. It has the f2t, it was in a rear end collision so they’re basically just selling the engine for about $400. I have the regular f2 in my car already, so I figured with the two engines I could work something out. They made it sound like nothings wrong with the engine, but it’s an old car that’s been sitting for at least 6mo.
 

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Oh really, how much are they asking for the whole car, so you can get wire harnesses, GT shit under the hood, sway bars...
What color is the interior? I need some blue or grey interior bits and trim from a 626.
 

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Well for 500$ what are you waiting for?
Too far to ship trim pieces but for a complete GT swap for you that is a bargain.
 

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I was looking for fastest, I was also told the KLDE was an option in some Ford Probes. I found a cheap Ford Probe with a KLDE in it, but the biggest problem for me is going to be getting new parts for the Japanese engines if I run into problems. Is the F2t still the best option with that as well?
If you're going for power, I'd stick with the f2/f2t... cheapest bang for buck setup for sure... as far as why anyone would want smooth, racing... not drag racing, but almost any other form of. Going that route i think I'd pick the kl over the Vulcan anyways, just for the weight aspect. As far as klde vs ze, I'd you're going for power, then likely you're looking for boost. The de would be just fine for that, no reason to bump the compression for boost. Ze cams would be nice, but a stock de at 10lbs. With a decent sized turbo scoots just fine. The f2 is nearly maintenance-less in comparison, though...
 

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If you're going for power, I'd stick with the f2/f2t... cheapest bang for buck setup for sure... as far as why anyone would want smooth, racing... not drag racing, but almost any other form of. Going that route i think I'd pick the kl over the Vulcan anyways, just for the weight aspect. As far as klde vs ze, I'd you're going for power, then likely you're looking for boost. The de would be just fine for that, no reason to bump the compression for boost. Ze cams would be nice, but a stock de at 10lbs. With a decent sized turbo scoots just fine. The f2 is nearly maintenance-less in comparison, though...
I would say smooth is not just engine related, it's the combination of parts and how they act together. Have you driven any auto F2T's? They have a much smoother acceleration curve than the 5speed because of the gearing, almost a night and day difference to the sudden violent torque spike of the 5speed using the same engine and turbo.
With the right sized turbo's, tuning and progressive boost control you could probably get the same powerband from the KL, Vulcan or F2.

Look at boring pathetic Canadian Rally racing, the cars are limited to 300hp (sad) but the engines and drive trains cost a fortune, making 300 peak hp is easy, all the money, effort and r&d goes into making 300hp from the time the throttle is pushed to red line. Basically these engines put out 300hp as soon as the driver is on the throttle.

Lets say the KL, Vulcan and F2 where all set-up to put out a steady 300hp or we used a 300hp electric motor bolted to the transmission instead, how smooth the power delivery would be would all depend on the transmissions gearing, with short gears the powerband would be violent, with tall gears the powerband would be smooth.

Proper turbo sizing is the most important thing. With the F2T if the turbo is too small or too big, it becomes an all or nothing type powerband, with the small turbo at half throttle you get full boost and with the big turbo at half throttle you get no boost, making it useless for racing. But with the right size turbo and set up at half throttle you get half the set boost, you have control of the power at the wheels with the gas pedal and can use as much or as little power as you want in corners.

Look at the old 911 rally porsches, the porsche drivers refused to drive the cars, the turbo's where too big and boost came on suddenly and at random rpm's making the cars extremely Not Smooth and dangerous, this was definitely not the engine that caused this powerband it was the turbo. With today's turbos and controls this could all be changed, a turbo that flows as much air could achieve different boost at different throttle, have a predictable and earlier spool and make the same or more power with a much smoother powerband.

It is really about how you set up the engine and what your goals are, with N/A tuned engines it's all about cam profile, intake manifold design and gearing, with forced induction engines it's all about turbo sizing. For drag racing you would want a really large turbo (possibly with something to help get it spooling like NOS), for racing light to light you would want a small turbo that spools instantly at any throttle position, for road course style track racing you would want a turbo that is in it's peak efficiency range at set boost at wide opened throttle but that is sized correctly to have usable varying power at different throttle positions. The small and really large turbo engines will not be smooth but the but the engine with the turbo selected for road course racing would be smooth.

All this is withing the reasonable potential of the engine, making 1000 hp with a turbo 2.0l 4 cylinder is possible but 80% of the power will come from the turbo and spooling a turbo that can flow 100lbs/min with an engine that flows at best 20lbs/min atmosphere is an all or nothing set-up.

The F2's longer stroke to bore ratio allows it to breath well (make torque) at low RPM, allowing it to spool turbos quicker at lower rpm than high revving 2.0l, this means with the right sized turbo it can have a usable powerband because it can breath enough to get the turbo spooling at partial throttle. The 2.0l with the same turbo will need to be at higher rpm and harder on the throttle to get the same sized turbo spooling, in a straight line at wide opened throttle this powerband will feel smoother than the F2's faster spooling, early torque powerband but at half throttle in a corner the F2 will be making some boost and the 2.0l will be making none or full boost.
 

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Partially... everything you said to smooth out the f2 could be applied to the other engines. Having driven them all as a 5 speed, the 2 v6 engines are definitely smoother about applying power in their mostly stock state. The extra smaller cylinders will also help smooth out all out. Putting taller gears on the f2 would definitely do wonders for this as well, but options are limited, the Vulcan has similar gears, as does the kl, although both boxes are much better about the 1-2 shift than the f2 box, and both v6s i feel are much smoother than the f2. I do feel the stock turbo is a big part of this as well... and to be fair, never drove the Vulcan with a turbo, or may be just as bad in that situation, but expect all would be fun with a decent sized turbo. I would love to put a decent cam and good turbo on the f2 to see what comes out, but I throw very little time at my cars anymore, but I do have a build in mind. I have the setup in a rally cross build currently, but am looking at the turbo now, finally lost the stocker i had been running on.
 
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