4AGE swap into 85 4WD

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JDNightFox
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My tercel:: 1986 SR5 / 1987 SR5
Location: OKC

Re: 4AGE swap into 85 4WD

Post by JDNightFox » Wed Oct 17, 2018 1:56 pm

Question

Does anyone have both the 4AGE crank timing gear and the 3AC timing gear to compare? Are they the same teeth # and shaft diameter?

teranfirbt
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My tercel:: '86 SR5 4WD, 5AFE, lifted rear, 195/70/14 tires
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Re: 4AGE swap into 85 4WD

Post by teranfirbt » Thu Oct 18, 2018 9:11 pm

Yes, 3ac and 4age timing belt pullies are the same.

Jdonnel
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My tercel:: 1983 Toyota SR5 4WD

Re: 4AGE swap into 85 4WD

Post by Jdonnel » Sat May 02, 2020 3:02 pm

Digging this up from the grave, have any of the 4AGE Tercel flywheels?

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Petros
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My tercel:: '84 Tercel4wd w/extensive mods
Location: Arlington WA USA

Re: 4AGE swap into 85 4WD

Post by Petros » Sat May 02, 2020 9:47 pm

Jdonnel wrote:
Sat May 02, 2020 3:02 pm
Digging this up from the grave, have any of the 4AGE Tercel flywheels?
a "4age Tercel flywheel"? no such thing, you have to make one from other parts, the 4age has 8 flywheel bolts, and the 3a, 4a, 7a engins have six bolts. three options:

1) use a 3ac flywheel, have a welding shop weld up 4 of the six holes (requires special knowlage of cast iron welding so they do not warm and ruin the flywheel), than have a machine shop clean up the filled in holes, and drill it so there are 8 bolt holes. requires accuracly placing the holes so it matches the back of the crank. this requires you to use the 3ac clutch, get a good Aisin one, the extra power will wear it out quickly. there are not a lot of options for high performance Tercel clutches. it would be advisable to have the machine shop cut down all the excess weight on the 3ac flywheel, it is massively heavy and not desirable for a high performance engine, and than have it balanced. Stock flywheel is 22-23 lbs, you should be able to cut it down to about 14 lbs. and reblance it.

2) Use the 4age flywheel, remove the ring gear (see instructions on Youtube, easy with heat), and have a machine shop cut a new land for the 3ac ring gear that you removed off the 3ac flywheel. Requires an interference fit so it stays in place. This allows you to use the larger 4age clutch, and there are many more performance clutch options available. stock flywheel weight is 16 lbs, but it would be desirable for the machine shop to cut that down further, and reblance it.

3) find a 4ac crankshaft with 6 bolt flywheel, and the same size journals as your 4age crank (the diameter changed over the production run, so make sure they match), install the 4ac crank into the 4age engine with new bearings (check for correct clearance), and use the 3ac 6-bolt flywheel and 3ac clutch. again, might be worth it to have the 3ac flywheel lightened and balanced. this option allows for a bolt up, no machining option, but leaves you with the smaller clutch and heavy flywheel.

doing this is not exactly cheap, unless you have access to a machine shop and you have the skills. none of the machining steps are particularly difficult for a skilled machinist and a well equipped machine shop. but the 4ac crank swap gives you a bolt up option that will work.
'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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Petros
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Re: 4AGE swap into 85 4WD

Post by Petros » Sat May 02, 2020 9:52 pm

I have a good 3ac flywheel with the welded up holes in it for sale, if anyone is interested. it is ready for a machine shop. I started doing this and changed my mind to use the 4age flywheel machined down to fit the ring gear.

it cost me about $90 to have it welded up in a specialty welding shop, plus the cost of the flywheel from picknpull. I have no plans to use it now.

$100?
'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)

Sgt.Tacticool
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Re: 4AGE swap into 85 4WD

Post by Sgt.Tacticool » Sun May 03, 2020 12:25 am

I got my 4age flywheel machined for the Tercel ring gear and it was pretty expensive but I think it will be worth it in the end.
1984 Tercel 4WD SR5 (undergoing 4age swap)
1987 AW11 MR2 (eventual 4agte build)
1987 AW11 MR2 shell (eventual rally car)
1972-69-76 FJ55 "franken-cruiser"
1995 Suzuki DR350

Jdonnel
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My tercel:: 1983 Toyota SR5 4WD

Re: 4AGE swap into 85 4WD

Post by Jdonnel » Sun May 03, 2020 6:11 pm

Yeah I saw your post on the FB post, I saw this thread and there was someone selling already converted flywheels hence “4AGE Tercel flywheel” I’ve talked to a machinist close to me and it’s not too bad but there is a lag to when he could get to it. So I was hoping there was one already made and ready to go that someone wanted to sell.

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Petros
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My tercel:: '84 Tercel4wd w/extensive mods
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Re: 4AGE swap into 85 4WD

Post by Petros » Mon May 04, 2020 6:24 pm

never heard of anyone offering them for sale, what ever the price, it would be a bargain. I can not tell you how hard it is to find a competent person to get it done right the first time. it is more time consummating to find someone that knows what to do than to actually do it.

it would only surprise me because there is not exactly a hot market in taking these somewhat rare '80's ecnobox cars to do an complex engine swap. even with a more modern engine these cars are somewhat primitive compared to even the entry level new cars. I like it that way, but I suspect not for your average buyer.
'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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