3-AC hop-up or motor swap

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new2yotas
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My tercel:: 1983 tercel 4x4 sr5
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3-AC hop-up or motor swap

Post by new2yotas »

Hi, although ive worked on and rebuilt a few toyota motors, this is my first that ive owned..its a 83 4wd tercel wagon and im contemplating a 4a motor swap..my question is has anyone who lives in a non-emission state just got rid of all the ca. smog stuff and did porting , cam upgrade, weber, tuned exhaust, etc. and if so, where the gains in H.P. and torque significant? or is the 4a 1.6 engine just the way to go because of after market parts? ive read alot of the post about webers and corolla motor swaps, but havnt seen any yet on getting the most out of the 3-AC..the local pic-a-part here has a 87 4alc motor complete for $200..i also noticed a few newer 1.5 with 12 valves and could be wrong on this, 24 valves ? could these heads bolt on and run a carb?..it seemed like the distributor was in a bad spot on one of these..ashtray might need to be re-located...thanks in advance for any help/advice..
teranfirbt
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Re: 3-AC hop-up or motor swap

Post by teranfirbt »

A stock 4AC puts out ~90hp from the factory, so a use one would be closer to 75 or so. The head on the 3/4AC is pretty terrible, there's not much you can do to make it over 100 hp without a ton of work that would ruin drivability.
Newer Corolla engines (4AFE, 7AFE, or 4AGE) can all be swapped, but require a fair amount of custom fab work to make fit. The 4AGE is easier since you can find RWD intakes, but you still have to move the exhaust to the other side. The 4/7AFE need more custom cooling and ignition system work to make fit since they are set up to be transverse only. The 4AF is a factory carbed twin cam engine that wouldn't require all of the fuel system work, and could be run on a weber.
As far as newer engines, the 90's Tercels ran the E engines, which are not compatible with the A block.
If you really want power, there are the 20 valve 4AGE engines that make up to 170 horsepower, but they're Japanese only (have to find an importer and hope it's not trash...) and the transaxle in these cars becomes very marginal at that power level.
larry mcgrath
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Re: 3-AC hop-up or motor swap

Post by larry mcgrath »

I installed a 4age JDM v/20 black top , a couple of years ago. This set up has about 28,000 miles on it so far, you cant rev this up -red line is 8200 - and drop the clutch, the drive line would'nt take it for long. This made this little car realy runnnnnnnnnnnn. Kicked a Audi A6 2.8 leters ass 2 weeks ago , at 125 MPH, in Helena Montana. This guy was REALY PIIIIIISSSSED. This was a lot of work to do , not plug and play by any means. The wright up is in the gallery under Larrys tercel gets a v20 B/T, on page 2. Larry
new2yotas
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Re: 3-AC hop-up or motor swap

Post by new2yotas »

125mph sounds like a blast..i think I will take another look at the wrecking yard, it seems to me there were a lot of transverse engines with twin cams and 20 v or 24v..do I need to look for specific years? I was looking for 83-87 corollas..and if my memory is correct, there were some rwd yotas ,but I don't think they were 4a motors..Larry ,looks like a nice build, did you have a donor car for all the wiring?
larry mcgrath
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Re: 3-AC hop-up or motor swap

Post by larry mcgrath »

The only way to get one of these engines is to go on ebay, and find an importer--- these engines were never imported into North or South America -- air polution standards--. Parts for this Arnt avaliable through Toyota localy , most dealers have never seen one of these. This engine is what most of the drift racers run, in ae 86's rear wheel drive. Go to club 4age on the net,this is the sight that I used to figure this out. The wireing was quite a chore. this engine is a 2000 the last year these were produced. Larry
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Petros
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Re: 3-AC hop-up or motor swap

Post by Petros »

do not waste your time with a 3ac, it is not suitable for getting more power, the head gasket will not take the stress.

go 4afe, or 4age, or use the 4age with the twin side draft carb set up (costly, but you might find it on ebay).
'87 Tercel 4wd SR5 (current engine swap project)
'84 Tercel 4wd (daily driver, with on going mods)
'92 Mazda MPV 4wd (wife's daily driver)
'85 Tercel 4wd DLX auto(daughter's daily driver)
'01 Honda Civic (other daughter's daily driver)
new2yotas
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Re: 3-AC hop-up or motor swap

Post by new2yotas »

I wasn't planning on the same motor that larry is running, just something from a corolla with more valves than the 4ac..hopefully a rwd with exhaust not connected to the intake ..if it has twincams and was meant for efi and all the ecu stuff, im probably not going to consider it unless I can buy a intake or make one for a weber or twin side draft set-up as petros said..83-87 is ok? or any year 4age? this is where I really need some help..and what cars have the 4age motor? this wrecking yard has a lot of coronas and celicas and camrys..only a handful of corollas..jim
teranfirbt
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Re: 3-AC hop-up or motor swap

Post by teranfirbt »

Google is your friend. Start with the list on WIkipedia: https://en.wikipedia.org/wiki/Toyota_A_engine
If you want a carb'd twin cam A engine that's ~bolt in, you'll have to find 4AF (no E) in the yard, it'll be in late 80's Corolla sedans (87-89? something like that). It'll still require some fab to make the exhaust and cooling system work, plus the distributor will either need a hole in the firewall or add distriubtorless ignition with an aftermarket system. Check out my 5AFE build for ideas on the cooling system: viewtopic.php?f=6&t=11237

The taller twin cam engines also need more hood clearance. I chose to mod the hood, which keeps the transmission/axle relationship correct. Larry dropped his engine and transaxle 1/2" to make the black top fit under the stock hood.

A 4AGE out of a RWD Corolla GTS is your only option for an engine that has the cooling system set up correctly, but you'll still need the exhaust, and then you'd have to carb it and add aftermarket ignition control since the distributor is computer controlled. A RWD 4AGE with the factory wiring/ECU and fuel system for EFI would proooobably be the most straight forward swap in terms of custom fab. RWD Corolla GTS' are like fricken unicorns these days, although you might be able to find parts on ebay or car-part if needed.
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Petros
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Re: 3-AC hop-up or motor swap

Post by Petros »

if you want an easy swap, just stay with the same year collora based 4ac. They are an easy bolt in swap, all mounts, exhaust, intake/exhaust manifold will swap right over, dist in same location. Stock they are 90 hp as noted, you can tweak a few more hp out of it with a reground cam shaft from Delta Cams (about $40 exchange if I recall), and you can over bore about .040", clean up the ports and get about 100 hp out of them. I would also advise lightening the massively heavy flywheel (19 lbs, I lightened mine down to about 16, even less would be better), have all the moving parts blanced, set timing at 10 deg BTDC over the stock 5 deg.

I have owned and driven webber equipped 3ac and 4ac engines, and I am not sure the cost is worth it, I did not find it produced noticably more hp. You will also have to experiment with fuel jets to get the fuel economy up to about the stock engine. In both extreme hot and cold conditions the weber is not as good as a properly running stock carb, which has a lot of complex systems to improve drivablity, particularly in very cold climates. I actully like the stock car set up for daily driving, when all systems are working properly it is very reliable, economical, and has excellent drivablity. My ideal set up would be to switch to fuel injections, and using a stock EFI corolla you can swap over the wire harncen, ecm and all of the extrernal componets for one of the EFI engines.

For a more agressive swap to a more mondern engnie the 16 valve 4AF or AFE would be a good candidate, it is a high fuel ecomony engine with an excellent high torque curve that would be perfect for the Tercel4wd. As stated you would have to make a full custom exhuast system and header, and either cut a hole in the firewall (not recommened, you would have to lose your heater), or converted to a distrubutor-less ingition system (with wrecking yard parts and some messing around it would not cost too much, or you can buy after market conversions for big bucks). The TErcel4wd flywheel will bolt up to the 4af crank, so that saves y ou some trouble, it is a lower profile engine so you will not have to alter to hood to make it fit. A stock 4afe would put out about 110 hp with a custom exhaust, there are also some good after market parts that would allow even more output.

The 4age has the stock distributor in a good location and will about double your stock 3ac output, put a much more modern 16 valve head on it and you can covert to EFI and eliminate that darn carb. Or for big bucks locate a duel side draft carb set up on e-bay (popular with drifters, so they are available with intake manifold, likely about $1000). converting to a more modern EFI is actually cheaper using stock parts from a wrecking yard or ebay, even if more wiring hassles. Also with the 4age, there are lots and lots of after market performance parts, this engine came in both the corolla GTS (both in the earlier rwd and later transvers installation), and the MR2 (transvers install). You will either need to weld up the holds in the 3ac flywheel, and have it match drilled for the 8 bolt crank of the 4age, or take a stock 4afe flywheel and cut it down to fit the Tercel smaller ring gear (this would be a good time to lighten it as well). And you will also need a full custom exhaust system. and alter the hood with a scoop or something to get an addition 1" clearance (or as larry did, alter the engine mounts and make a custom oil pan to lower the engine). There are a few early 4age that have the six bolt crank, not sure what year, perhaps only first year. The first generation of 4age (up to about '85 or '86 I think) will take a 3ac/4ac crank, dimensions are the same and you will not have to custom make the flywheel. This would only be a good idea if you were overhauling the whole engine anyway before the swap. the early 4age will take the Tercel oil pan and pick up, which you need to swap out to work in the Tercel, same as the 4ac/4ag. All of the hard points for engine and trans mouts are the same on a 4a engines. the best 4age for the a swap would be from the same year GTS, or MR2, '83-'87. There were also supercharged models that boost power, and a later turbo charged model that will tripple your power output over the stock 3ac. I do not think I would want either of those on a daily driver, fuel economy will be affected and I doubt the extra trouble would be worth it.

Larry McGrath used a much more powerful newer engine, he has lots of excellent skills to be able to do this kind of swap. He had fabricated lots of the sheet metal parts himself, and got it to work. He did a great job on it (see the thread on the topic). He has an excellent conversion/swap, but it was not without lot of work, custom fab'ed parts, and some troubles.

I am currently drive a 4ac, over bored with the reground cam shaft, cleaned up ports, balanced and lightened flywheel, and I am very happy with it (stock carb/exhaust). Not a big power house, but it will pull out on to the hwy without me fearing getting run over by logging trucks (I have inadvertently red lined it at over 7000 rpm, all of the power is at the high end). Though I have long term plans to put a 4age into a project tercel, I am slowing accumulating the parts I need, and some day I may actually complete it.

My ultimate Tercel4wd would have the twin cam 16 valve 4age with EFI, the later 4:10 final drive, rear limited slip diff, 4 wheel disk brakes, with the larger MR2 front vented rotors, larger front and rear struts/shocks and slightly stiff springs, and custom leather seats. I am slowly working towards that, but this would cost about $4000 or more in parts alone, if you paid to have this done you would be into over $10,000.
'87 Tercel 4wd SR5 (current engine swap project)
'84 Tercel 4wd (daily driver, with on going mods)
'92 Mazda MPV 4wd (wife's daily driver)
'85 Tercel 4wd DLX auto(daughter's daily driver)
'01 Honda Civic (other daughter's daily driver)
new2yotas
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Re: 3-AC hop-up or motor swap

Post by new2yotas »

Lots of good info here, I did make it to another wrecking yard today and there was a twincam 16 v efi ..ill hit the other wrecking yard tomorrow and see what they got..talking to the owner of this little yard, he told me ten years ago he had a lot of those twin cam corollas and they crushed them..he said he wont do that now that he knows people want them..lol
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Re: 3-AC hop-up or motor swap

Post by Petros »

If you have room you would be best to get a whole car, even if it was wrapped around a tree. there are lots of useful parts to pull from an EFI car that you will need. If you can get a whole wrecked rwd corolla GTS, you will get a lot of useful stuff, like a rear axle with disk brakes and a limited slip diff, that can be adapted to fit the Tercel4wd, in addition to the EFI fuel pump, high pressure fuel lines, intake, etc, as well as the engine.

I wonder if you can work out a deal with the wrecking yard owner to find one at an auction for you, and he delivers to your back yard directly from the auction yard for a fast and easy profit.

what parts you do not need you can sell on ebay. When done stripping it you can drop off the remaining hulk to the wrecking yard so he can get a few $ in scrap off it.
'87 Tercel 4wd SR5 (current engine swap project)
'84 Tercel 4wd (daily driver, with on going mods)
'92 Mazda MPV 4wd (wife's daily driver)
'85 Tercel 4wd DLX auto(daughter's daily driver)
'01 Honda Civic (other daughter's daily driver)
new2yotas
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My tercel:: 1983 tercel 4x4 sr5
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Re: 3-AC hop-up or motor swap

Post by new2yotas »

Well ,good news I bought a motor..its a 4 AGE out of a 85 MR2 ..now it wasn't a carb engine and I guess none of the mr2's were..so I hope i can find/make a dual carb set up..its buried in a guys garage so i wont get it til he clears some stuff..he has the exhaust manifold and lots of misc.parts that go with it..i will take some pics before i tear it down and post the before pics of both engines..thanks for all the help with getting me started guys..im going to start my search for those dual carb set up and see what ebay and amazon has..if anybody needs a good running 3ac with 115,000 mi..pm me Jim
new2yotas
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Re: 3-AC hop-up or motor swap

Post by new2yotas »

then again, i might need the crank and flywheel, and oil pan off the 3ac..so if anybody needs whatever is left when i get done, well you know..lol
teranfirbt
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Re: 3-AC hop-up or motor swap

Post by teranfirbt »

Flywheel and oil pan for sure. You can mod the stock Tercel flywheel by having 4 holes welded closed and then drilling 6 new holes to match the 4AGE crank. You'll want to have a machine shop do that since they need to be precisely located.
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Petros
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Re: 3-AC hop-up or motor swap

Post by Petros »

I have both welded and redrilled the 3ac flywheel, and cut down the 4age flywheel. the welding and machining both requires different skills that need to be done properly or you will ruin the flwheel. Per Larry McGrath's experiance, cutting down the 4age flywheel so it will take the 3ac ring gear I think is easier, he details it on the thread about his engine swap. I have also done this, and it is easier to find a competent machine shop that can do this work (preferably an automotive machine shop that can also resurface it and balance when it is done). You also get the beneftit of a larger clutch using the 3age flywheel.

wait until you actual get the engine, there are some early 4age engines that have the six bolt crank, so the 3ac flywheel would be a direct bolt on swap. though the larger clutch that fits on the 4age flywheel is a benefit, it would save a lot of money to use the stock 3ac flywheel and clutch (though it still is rather heavy for a flywheel).

You will also need the engine mounts, the steel backing plate off the 3ac engine (goes behind the flywheel), oil pan and oil pick up, the alternator mounts, power steering mount and a lot of other external parts from the 3ac.

there is a thread on this forum on how a forum member from Prescott AZ installed 4 motorcycle carbs, by making his own intake manifold, on his 3ac. If you are going to make your own intake manifold anyway, that would be good way to go, since these motor cycle carbs are fairly common and often the owners of these motorcyles will up grade to larger carbs, so used once are commonly available off craig's list or ebay cheap. I think they were suzuki carbs, but I do not recall what they came off of. It looked like a nice set up, and if you can make the intake manifold, an inexpensive way to go. He had to rejet them, but different size jets were inexpensive.
'87 Tercel 4wd SR5 (current engine swap project)
'84 Tercel 4wd (daily driver, with on going mods)
'92 Mazda MPV 4wd (wife's daily driver)
'85 Tercel 4wd DLX auto(daughter's daily driver)
'01 Honda Civic (other daughter's daily driver)
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