3-AC hop-up or motor swap

[Petros]

you can find the the adjustable 4age cam sprokets on ebay, some of the specialty toyota performance parts sellers also have them.

I would just hand resurface the head and block top (see my head gasket thread over in the repair guides section for the procedure), hone or bore the cylinders if necessary, and clean up the ports. Making the intake ports larger will harm low end performance, so just clean them up. Go as large as you want on the exhaust ports, or they can be cleaned up too. The stock engine about doubles the power output already, with the cam sprockets to detune the engine so it is not as peak as high will actually improve low end acceleration over the stock engine too.

[new2yotas]

when I get ready to pull the 3ac motor, is there any reason I shouldn't pull all the smog stuff?..also if anybody needs or know someone who wants a good running stock motor, its going to need a new home and the price is right..im 5 hrs. south of Portland and 5 hrs. north of bay area..97601

[new2yotas]

well im getting ready to clean the block and paint it..all the parts I ordered, should be here sat. so assembly will go next week..ive got an idea on how im going to fabricate a intake manifold out of the plentum I got with this motor..it also has a vacumn operated air plate that goes between the block and plentum..at first glance I thought it was an emission thing, and I normally wouldn't even think about putting this on, but mabe it will help with fuel milage.while I was at the wrecking yard, I found another corolla and I was wondering if the 4afe exhaust manifold would bolt onto my 4age? its a manual trans, with a transverse motor..i remember you or another member lettimg me know that a 4ac will bolt right into my sr5 and flywheels were the same..is the flywheel on a 4afe the same as the 3ac or is it like the 4age?..last but not least, is there a place to download a manual or engine specification page for the 4age..im looking for bearing tolerances,crank end play, torque sequence & specs etc etc..

[teranfirbt]

Rock auto lists the same part numbers for exhaust manifold gaskets between the 4AFE and the 4AGE, so should be able to go either way.
Tercel 3AC flywheel is unique to the Tercel, but the bolt pattern is the same as the 4AFE. The 4AGE has 8 bolts instead of 6, so you either need to mod the Tercel flywheel to have 8 holes or swap the starter ring from Tercel to 4AGE flywheel.
Torque sequences will be the same as what's in the Tercel FSM for both the bottom end and the cylinder head. If you can find an MR2/Corolla GT-S manual that will give you 4AGE numbers, although I imagine they are basically the same as the 3AC for tolerances.

[new2yotas]

that's great, thank you for the reply..whats FSM, I see you guys writing that one a lot..something service manual?..anyway I think I will get that exhaust manifold, then all I will need is a 4age flywheel and some time to turn it down to fit my ring gear..and either im computer stupid or the attachment link is broken..i still cant post any pics..but my kid is going to come over soon and ill let him try to get them uploaded..now heres a dumb question, does the 4afe flywheel have the same clutch as the 3ac or is it heavier/bigger like the 4age? ive got the old clutch and pressure plate from the mr2 and if the bolt pattern and ring gear are the same, why couldn't I open up the flywheel to fit the clutch..i have a lathe..

[teranfirbt]

No idea on the clutch, I'd have to see em side by side. Rock Auto often lists basic dimensions for things in their part listing. FSM is indeed Factory Service Manual, there's a link in the general chat section to the Tercel manual for 1985, which will cover most years of AL25.

[Petros]

flywheels are usually unique for each car, no matter what engine it is bolted to. the corolla 4afe flywheel and clutch I had was NO way interchangeable with either MR2 or Tercel, the flywheel goes with the trans, and also starter mounting location, which can be on different sizes on the different cars, even with the same engine.

I would be suprised if the 4age exhaust manifold interchanges with the 4afe, the angle of the face is different relative to the head gasket surface. Might work, but that would surprise me.

You will likely need a completely custom exhaust header because the steering linkage and cross member is in different location (as is the starter) on the Tercel than in the cars the 4age comes in. Someone made an MR2 turbo exhaust manifold work (it is very short and compact, and only had one head pipe, so easier to make work), but it is less than ideal. I bought from ebay a corolla GTS stainless header for the 4age, it will not work in the tercel, but it was cheap enough I thought I could cut it off about 8 or 9 inches down from the gasket face and have a muffler shop fit tubes in around the steering linage, starter and cross member, gives them a head start on the assembling of parts. you might be able to get a the cast iron 4age exhaust manifold used in the GTS RWD corolla, if you can find one (might be some over on the 4age forum selling one since they have gone to a custom header). yOu will still need to make a custom head pipe, but again, it should get the msot complicated part done for you.

AS far as intake goes, yes that throttle plate-like device improves low end performance by keeping the intake velocity up, I have seen power curves with and without, improves low end power quite a bit (cleaver design).

you can also fabricate a cab manifold fairly easily by using hose clamps and stiff rubber hoses, one for each runner, to mount 4 motor cycle carbs on it. There is a thread where someone did this on a 3ac, used Kawasaki carbs as I recall, got them cheap because lots of owners switch to larger carbs and dump the stock ones on Craig's list. might be an interesting combo for a non-fuel injected 4age (it will certainly greatly simplify the engine swap). here is the thread, pics are gone unfortunately: viewtopic.php?f=2&t=6690

[new2yotas]

here goes my third attempt at some pics..lol I got them on my desktop, then clicked attach and add files, drug the first one over to message box and ..shit! error file is too big..really? 1 picture..tomorrow is another day

[new2yotas]

Well its official, the 4afe exhaust doesn't fit a 4age..not even close! oh well it was worth a try..and along with flywheel and exhaust, I will need an oil pump..i broke the idler pulley clean off..i did notice that rockauto has flywheels pretty reasonable..and 4 different oil pumps..i think oem might be aisin?..I surfaced the block , and built aluminum plugs for the injectors..time to do a little porting and im not going to hog a bunch of material out of the exhaust, but I will match all 4 and polish..intake is already deburred and I like to leave the intake a little on the rough side to help atomize the fuel..

[Petros]

no benefit to leaving intake rough, you have a boundary layer that slows the flow, roughness just makes boundary layer thicker and slows it more. leave it small dia, yes, make it smooth, sandpaper finish is good enough (some advocate mirror finish, but that too is lost in boundary layer, but looks cool).

both carbs and fuel injectors put relatively large droplets into the intake manifold, but normal turbulence at the valve breaks it up well. The EFI gets it evenly distributed in all cylinders so it greatly improves power and efficiency.

[new2yotas]

I bought a used flywheel on ebay and it showed up today, the funny thing is its got 85 MR2 written in crayon ...it was listed as a corolla, but hey my motor was suppose to be out of a 85 MR2..the clutch disc fits the wear line perfect, but the pressure plate is a tad bigger..its got 8 holes and im wondering if they made 2 sizes and I got the smaller one..and will the ring gear be right?ive tried to look up 3ac flywheel specs and cant seem to find anything on them..but the disc is 8 7/8 and I believe the ring gear has 106 teeth..mabe I will get lucky and it will fit..lol I got my twin SU manifold built out of the MR2 plentum..don't know if the hood is going to close, but I will deal with thatlater..it sure looks cool and my kid couldn't get the pics to go on here either..but ill keep taking them and put them in a folder til somebody smarter than us comes over..

[new2yotas]

ok, I think I got the picture problem solved, heres a few tear down and before pics

[new2yotas]

more pics and I had to snap the one of the goat..i pulled up to an intersection the other night and this guy gives me in my tercel the thumbs up and I thought, wonder if he needs another motor? so I asked him and he said sure, he followed me a couple of blocks to my house and I didn't even see the goat until he got out of his car and turned on the l.e.d.s...I couldn't stop laughing and my neighbors came out laughing too, because the goat was making a racket..lmao again I asked him what he was doing with the goat and he said it was his girlfriends and was taking it to her barn..sorry I couldn't resist..there wasn't a category for tercels/farming

[Notmikeb]

I've been trying to convince my wife that we need a Bridgeport style mill for years now. She keeps insisting that we spend our money on useless things like "food" and "the electric bill" instead. She just doesn't get it.

Nice job on the manifold btw! Looks professional.

[new2yotas]

Thank you, and I wish I was retired so I could spend more time in my shop, atleast semi-retired so it wasn't so cluttered..im kinda embarrassed now that I woke up and looked at those pics..my son figured out that we had to re-size all the pics in Paint and then save them ..there still awful big when you click and zoom...well im off to work for a short day I hope, then figure out the rest of the linkage ,enricher/tickler cables, and a whole bunch of vacumn leaks to plug off..with these carbs, it looks like im only going to need the 1 port for the brake booster..! 1 vacumn line on a tercel? .. That cant be right can it? lol