Engine Swaps

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Topic author
sierrablue
Posts: 1208
Joined: Wed Nov 30, 2022 8:02 pm
Location: MN/CO

Engine Swaps

Post by sierrablue »

In light of the recent trend of engine swaps, I'm curious about what people see as the "ideal" engine swap.

For me, I'm more of an EV guy for a couple of reasons, but this is for combustion engines.

I know a lot of guys do the LS and Hemi swaps, but the LS is mostly for the cost and the Hemi is for the sticking with Mopar (and has similar advantages as the LS). My less-than-love for the LS has been made pretty clear (sorry to anyone who has taken offense at that). I understand Fords are more expensive but for the all-out builds I don't understand why NOBODY has gone with the Fords. The OHCs do legit help, and most of them are smaller (and thus get better mileage when you're not screwing around).

Really though, if you get a decent twin turbo I-4, you can keep up with all the V-8 guys and not lose so much power at altitude. And torque isn't a problem with the I-4s, so I don't understand.

What all do you guys think? Assuming money is no object, best swap? Best budget swap? Best bang for your buck (but not nec. cheapest) swap?
'71 Wagoneer (DD)
-B350 (HEI, iron 4-barrel, Edelbrock 1406), TH400, D20
-'74 D44 front (nonpower discs)
-custom headliner
-Front shoulder belts (rears eventually)

viewtopic.php?t=23070

There are 2 major differences between new Wranglers and FSJs. FSJs are meant to be both utilitarian and capable, not just capable. FSJs are also rarely initially recognized as Jeeps by the average American.

will e
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Joined: Sat Aug 18, 2012 8:21 am

Re: Engine Swaps

Post by will e »

Money no object? I'd probably still stick with my AMC block, maybe fuel inject it. Add a OD transmission.

The answer depends upon use case. Mine is primarily a wheeling rig and sometimes weekend driver. A twin turbo I4 won't provide the low range torque/throttle response I am looking for. Diesel swaps are an interesting option but my main goal is to get to and through a trail. Keeping the AMC/tf727 keeps it simple and pretty darn reliable (if not a bit leaky). If my rig was a DD or tow rig my 'best swap' might be somthing different.
81 Waggy 'WILL E' Retired
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Yeller
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Location: Rogers County Oklahoma

Re: Engine Swaps

Post by Yeller »

Great discussion!

I’m not a purist in anything, I’ve swaped GM engines in fords and ford engines in GM’s. It just depends on end goals, budget and what is available. From a cost, aftermarket suport, overall ease of fitment, and availability it’s hard to argue the LS platform. Next Is Mopar and last is Ford. The other issue is longevity of parts availability, a 20 year old LS, every part of the control pack is readily available, hemi, sort of and ford is a total crap shoot.

The reason you don’t see many ford mod motor swaps is simple, they are wide, factory control units and many parts are not only 1 year but vehicle specific makes them difficult to work with. They also have issues with cam phasers, coils, and often ecm compatibility issues. It’s not that it can’t be done it’s when it is done can you get parts. Even Coyote swaps are very difficult, the engine is wide and long and year/vehicle specific control packs and in some cases not interchangeable all of this adds up to expensive. To make real gains super charging is the only way to make large gains in power out put.

As for Mopar options, they are not as difficult as Ford options but do suffer from limited suport. Like LS motors they respond very well to cam changes. They are also of a physical size that lends themselves to fitting well in most engine compartments. I know a lot of people who have replaced small block fords with coyotes, they love them for the drive ability but many do not make the total power that their old school hot rodded engine made.

Ok the elephant in the room, the LS you get the advantages of the hemi with virtually unlimited suport for every facet of the engine, they respond well to any forced induction and cam swaps, 100 horse power gains with nothing but a cam and tune are realistic. They are compact and fit well.

As for the turbo 4/turbo 6 swaps. I looked into it when we got down to needing to figure out over 900 lines of code to get it to run correctly along with the cost it just wasn’t worth it. They were also larger than you would think, I’d be surprised if either would fit in the engine compartment with the cooling pack. Albeit cool to make work, just too many variables making it complicated, expensive and unreliable. They also loose their favor with the poor aerodynamics of our trucks, it takes torque to push the brick, to make torque they require boost, in the boost all the time, you lose the fuel mileage dream or advantage depending on how you look at it.

Let’s not forget transmissions. For all out performance can’t over look the transmission, the 6 and 8 speed transmissions when combined with a matching engine really make that engine perform.

For me the ultimate currently is a stroked 427 LS with a 6 speed auto. Naturally aspirated to 600hp, reliable and easy to drive and a riot when told to be angry. Although times are changing, ford has a huge desire for the aftermarket OEM crate engine market, that they really have not had a piece of. The 7.3 gas program is looking to be very promising, watching close. The potential for 800hp naturally aspirated are real and the transmission options are robust. The engine isn’t much larger than an LS and is much smaller than a coyote.
The bus I ride is so short it is a yellow Smart Car full of squirrels, monkeys and clowns.

1970 J2500 Resto Mod
https://www.fsjnetwork.com/forum/viewt ... 12&t=21395

1974 Bronco “Broncno”
https://classicbroncos.com/forums/threa ... st-3411909

Topic author
sierrablue
Posts: 1208
Joined: Wed Nov 30, 2022 8:02 pm
Location: MN/CO

Re: Engine Swaps

Post by sierrablue »

I kind of get the "it's big" argument with the Coyotes and stuff, but I'm not sure that argument holds up in a FSJ. Especially for the guys running a body lift anyway. And since the modular Fords don't have the spark plugs way down next to the heater box; they're more on top, you can't argue that they're impossible to work on either. Additionally there are a LOT of guys who put them in early Broncos...if they fit there I would HOPE they fit in a FSJ. Am I missing something here? They're aluminum do they're not super heavy...

As far as parts go, you kinda just need to know your equipment, right? And they're still using the Coyote in the F-150s, and Mustangs, and have been for over a decade now--as long as you know what you have what's the problem? It's certainly not going to be any worse than having to ask for axle parts for a '74, engine parts for a '70 Buick (or SBC because they use the same parts but the Buick doesn't come up in the system), a voltage regulator for a '71, and dome lights for an '88...never done anything like that before lol

The other thing I forgot to bring up in my first post--as far as 6s go I have two 6-cylinders I like, ok, 3 if you mod the one, but that's pretty much it.

First there's the new Hurricane from Mopar--finally a straight 6 that brings all of the available technology at the time into one good, light, and powerful engine. My only issue with it is that now it's time for EVs--Mopar is late to the "make a really good engine" game.

Second I really like the Ecoboost V6--it's just a good all-around engine. It lasts, makes decent power, can be modded to make ridiculous power (exhibit A--the Ford GT Mk2), and doesn't suck TOO much gas in it's tamer forms.

The other one I like is the old Tornado that came in the FSJs originally. Really it's not a bad design, it just suffers from a lack of support and low compression. I've read that LS pistons work...up it to 9 or 10:1 compression, 3d print an ITB setup and give it multiport injection (mass air), a good flowing exhaust, and high-output ignition, and it should be good to go. Also Renault adopted that engine and made racing versions through the '70s--none of this stuff would be cheap but it would be an incredibly impressive engine, and then if you added turbos...

As far as transmissions go, you're just never gonna beat the efficiency of a manual; whether it be a true manual or a sequential (which, I highly doubt anybody would need something that shifts that fast in an FSJ, except for the handful of drag cars). Only advantage is that you don't have to mess with the clutch yourself, depending on the sequential setup, which I suppose would be nice for the crawlers.

@SJohn, I also like the 2JZ; I just don't feel like the FSJ is a good application for something with so little torque ;)
'71 Wagoneer (DD)
-B350 (HEI, iron 4-barrel, Edelbrock 1406), TH400, D20
-'74 D44 front (nonpower discs)
-custom headliner
-Front shoulder belts (rears eventually)

viewtopic.php?t=23070

There are 2 major differences between new Wranglers and FSJs. FSJs are meant to be both utilitarian and capable, not just capable. FSJs are also rarely initially recognized as Jeeps by the average American.
User avatar

Yeller
Posts: 1521
Joined: Thu Apr 01, 2021 7:54 am
Location: Rogers County Oklahoma

Re: Engine Swaps

Post by Yeller »

Yes coyotes do fit in an early bronco sort of. The inner fenders have to be relocated to make room. Firewall needs a few mods, brake booster bracket needs replaced, custom oil pan has to be sourced along with a 1” body lift and custom accessory brackets so the radiator fits. In comparison, an LS bolts in with about 10 minutes worth of mods to the original v8 motor mount frame brackets with a 1” body lift on a cowl hood the truck intake fits under the hood and is complete from fan to flywheel. Original 302 radiator even is usable. I have less hours installing an LS turn key than just getting a coyote to fit, let alone run. Don’t think for a minute that the coyote is small, for its displacement, it is very large.

Efficiency of a manual died several years ago. Todays automatics are not the T400 or the torqueflight of yesterday, they are efficient and have enough gears to always have the engine at the correct RPM. Semi trucks are probably the best example, they are almost all now automatics, fuel mileage is better, and repairs are less frequent, all of which is king in a working truck. The best driver cannot out shift a computer as long as the computer has the right algorithms to do it correctly. I only use that as an example due to not only it’s widely documented, I can attest to it watching our fleet at work. New autos in passenger vehicles with up to 10 gears are very efficient at power transfer and fuel economy.

I miss manuals, I like the driving experience and the feeling of control it gives, having driven race cars with both, I can tell you in power transfer efficiency it’s auto all the way but for the best visceral experience I want 3 pedals and a shifter.
The bus I ride is so short it is a yellow Smart Car full of squirrels, monkeys and clowns.

1970 J2500 Resto Mod
https://www.fsjnetwork.com/forum/viewt ... 12&t=21395

1974 Bronco “Broncno”
https://classicbroncos.com/forums/threa ... st-3411909
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