Engine swap for '85 SR5

[Godspeed Oakland]

I bought a hard to find 6-speed tranny for my 3-spd automatic 1985 Tercel SR5. I also got a 4 AGE Silver Top engine, as I was told any 4 AGE motor would bolt in. However, I found that the engine does not bolt directly up to the tranny as the 8 bolt flywheel on the silver top is too large to fit inside my '85 6-Speeds' bell housing; as the stock motor came with a smaller in diameter 6 bolt flywheel.

So, is there a a conversion flywheel I can just order up? If not I will sell the engine and buy a 4 AGE motor that is a bolt in. Which year and model of 4 AGE motor is the highest performance engine that I can bolt in to my car without problems? Would like one that I can turbocharge if possible. I have access to a stand alone fuel injection system, as my stock 3A motor is carb'd.

Thanks again,

Dan

[Lil Beast]

You won't find any 4age that the flywheel will fit straight forward in the 1st and 2nd gen tercel, even the later gen do a tranny swap as well from corolla's or mr2's to fit with the flywheel! What I did, I brought thr tercel flywheel to a machine shop to fill up 4 holes and redrill matching holes of the 4age flywheel.

flywheel%20hole%20plugged%20and%20redrill.jpg

I guess if you got access to a good press drill or a drilling/milling machine you can do it easily, mine is 5000 km away for now, so paid the machine shop 200$ for the job fair enough! Cheaper than another engine. If you got money you can do the same to one of those exedy or other brand lightweight tercel flywheel. Or put it on a lathe but it will need to be rebalance. Kind of costly if not equipped at the machine shop they would of charge me 500$ extra to get it done so I backed out. When I'll have more money and further down my project when I feel the need to, I'll get one!

[dlb]

dan, there are some fairly comprehensive threads on the 4AGE swap. just do a search from the main page of the forum for 'engine swap' and you should find them.

[4wdchico]

A turbo 4age will equal transmission destruction for the manual trans. If you really want a turbo 4age T4wd you would be much better off with a good working version of the automatic that came in the car. Even a healthy built 4ac can be risky for the manual trans.

[Petros]

welcome to the list Godspeed,

The easiest thing to do is have the 3a six bolt flywheel modified. Over on the 4age swap thread there is a lot of details about it. You need to find a welding shop that knows how to weld cast iron (they heat it up to a dull red glow and than weld in 4 bolts holes), than a machine shop has to exactly match the 8 bolt pattern. I had it done by an excellent machine shop for about $200, which included lightening the flywheel to 14 lbs (from the fat 19 lb stock wt.).

Supposedly the earliest version of the 4age (1983?) had a six bolt crank but no one in North America has seen it. Also it appears that certain years of the 4afe crank use the same size bearing journals and might swap across to the 4age, it uses a six bolt crank. Or you can put the 4age head on a 4afe short block, there are even a few who have put the 4age head on a 7afe short block to make a 7age. Both the 4afe and 7afe use the six bolt flywheel.

You have a few other issues beside the flywheel, a custom exhaust header and exhaust system to fit past the steering column, and the hood clearance. The engine is too tall to fit under the hood, so you either have to put a scoop or other bulge in the hood, or you have to make engine mounts to lower it. The other option is to install the later 4 individual throttle plates from the small port motor, which requires an adapter plate to fit on the earlier large port 4age. And than there is the adapting of the EFI system too, high pressure fuel pump, fuel lines, wiring, etc. There is a duel side draft carb and intake manifold set-up available for the 4age, but it is pretty costly even used (more than buying the whole engine). but it solves several challenges with the EFI system.

[Godspeed Oakland]

Thanks guys. I will find the 3A flywheel and mod it to the 8 bolt pattern of the new motor. I have a stand alone EFI system that has all the pumps, lines, harness... to work with the new engine. Prolly just go NA with the 6 speed, as my 3 speed auto is wasted too. Ill mod the Hood if needed. Thanks for the info!

Can I drop a 4FZE MR2 supercharger engine into my car doing the same mods we discussed before, and keeping the AWD setup I already have? That would be cool!

[Godspeed Oakland]

welcome to the list Godspeed,

The easiest thing to do is have the 3a six bolt flywheel modified. Over on the 4age swap thread there is a lot of details about it. You need to find a welding shop that knows how to weld cast iron (they heat it up to a dull red glow and than weld in 4 bolts holes), than a machine shop has to exactly match the 8 bolt pattern. I had it done by an excellent machine shop for about $200, which included lightening the flywheel to 14 lbs (from the fat 19 lb stock wt.).

Supposedly the earliest version of the 4age (1983?) had a six bolt crank but no one in North America has seen it. Also it appears that certain years of the 4afe crank use the same size bearing journals and might swap across to the 4age, it uses a six bolt crank. Or you can put the 4age head on a 4afe short block, there are even a few who have put the 4age head on a 7afe short block to make a 7age. Both the 4afe and 7afe use the six bolt flywheel.

You have a few other issues beside the flywheel, a custom exhaust header and exhaust system to fit past the steering column, and the hood clearance. The engine is too tall to fit under the hood, so you either have to put a scoop or other bulge in the hood, or you have to make engine mounts to lower it. The other option is to install the later 4 individual throttle plates from the small port motor, which requires an adapter plate to fit on the earlier large port 4age. And than there is the adapting of the EFI system too, high pressure fuel pump, fuel lines, wiring, etc. There is a duel side draft carb and intake manifold set-up available for the 4age, but it is pretty costly even used (more than buying the whole engine). but it solves several challenges with the EFI system.

Where can I find the Carb setup you speak of? I didn't know it was available for my Silvertop, I was told it wasn't...

[Lil Beast]

You can look up e-bay under "4age carbs", some fcr flatside will pop! They will be over a 1000$ shipped and everything! Kinda a pricey but are the best for tuning application! You can always use some bike carbs like suzuki gsxr, that's the route I'm taking. Got some carbs for cheap of e-bay as well for 70$ shipped, the only thing the remain mystery carbs for the moment as the seller told me they came off of a cbr600f3 and should be keihin and they are mikuni BST31 I believe, still got to do a bit more research! Good news in a way, as I been reading it was an upgrade to the bike. Makng adapter plates are pretty straight forward! The one's I've got are a little small 31mm but they will do fine for low end, for more top end 38mm up to 45mm could be use, but good chance it will spit a little at low revs.
Here's a good link for 4age carb info and jetting: http://www.club4ag.com/faq_and_tech_pag ... _4A-GE.htm

There is some cheap mikuni sets right now on ebay, one is mystery 32mm type in "mikuni 32mm" in the e-bay search tool to set will come in the list one is 9.99$ and the other 50$ both came off dragbikes, they are not that mysterious anymore to me(as mentioned,updated this post), got the same one's thought it was bst31 they turn out to be bdst32 been researching part of my evening on my carbs. Looking at a bunch of mikuni carbs for sale on ebay to identify mine, I've seen these same set going ranging from 400$ to 600$ for a rebuild set. There is a bunch of other size too(34/36/38/39/40,etc) at different price worth checking it out! It's mainly the jetting that's important, so most likely even the rebuild are wrongly jetted for 4age so your best bet could a mystery one and rebuild it to your needs, and for jets there's millions for mikuni, so far all seem to be interchangeable between carb series.

[Godspeed Oakland]

The ports are spread out differently on the 20V Silvertop motor than the 4V 4AGE motors. I would have to make a custom intake manifold. If I use the stock individual throttle bodies that came with the motor all I need is a DFI system and use all the stock components and it adjusts to altitude and temp automatically. It also is ready for boost or nitrous. I will prolly go that route. I may go with a motor that has a turbo kit available for it.

What tranny should I use that will keep my AWD? I have a stock 3speed auto and a 6 speed manual that bolts into my car...

[Lil Beast]

I'm driving the 3 speed auto for now but not very impress with it, was fine before the Weber. So just that little extra made the tranny to slip in D. Got to shift like standard with revs so it won't slip. I'm guessing it won't last 4age. I've got a 4 speed that I'm gonna use with the 4age. And looking for a good 6 speed for my 4wd conversion. Dunno how they will do! Should be alright for street driving!

[4wdchico]

A stock silvertop 4ag 5 valve produces 119ft pounds of torque. Anything above 100ft pounds is risky to the manual 6 speed t4wd tranny.

[Godspeed Oakland]

What do you mean by the t4wd tranny? is that the stock 3 speed auto or the 6-spd manual?

[Lil Beast]

They came in various applications FWD 3sp auto, 4 and 5 speed manual and 4WD 3 sp auto or 6sp manual!
I think he's referring to the 6 speed by t4wd!
There is a thread here: http://d1davey.com/ for how to turbo a 4agze! Dunno you might find it interesting!

[4wdchico]

They came in various applications FWD 3sp auto, 4 and 5 speed manual and 4WD 3 sp auto or 6sp manual!
I think he's referring to the 6 speed by t4wd!

Yes, the 6 speed t4wd trans.