To swap or not to swap? Ice racing Tercel

[shanehutton]

I am ice-racing my 87 and it has been very competitive when it is really slippery but on days when there is a lot of grip I just don't have the power to keep up with the faster cars on the straights (legacy turbos, 20v Audi etc.). This leads me to some options for this summer's off season:

Should I swap in a 4age or try to get more power from the 3a?

Are there any informative websites / threads about the 4age swap (parts lists / step by step)?

Could anyone weigh in on what sort of power I would get out of the following on the 3a:
-Weber 32/36
-Throttle body injection with megasquirt
-More aggressive cam (source for the cam?)
-headwork (is there a bottleneck somewhere)
-Is there anything else worth looking at?

If I stick with the 3a I will probably end up revving it to 7000rpm quite often so is there anything I should address? Valve springs perhaps?

Here is a picture of the car in action.

Feb 6th Rusty600.jpg

[Neu]

I wanna say welcome to the forums.

Make sure to post threads with a lot of pictures of any upgrades, that's always really appreciated.

[ARCHINSTL]

Welcome! I think your ice racing is a new venue for the Mighty T4WD!
Tom M.

[danzo]

Welcome to the group, you have an interesting paint scheme. I ice raced once when I lived in Boston, but not in a T4wd. Where are you located? There are a million different ways to get more power from our cars, just like almost any car. Your best bet is to search the forums here, there's alot of great info. It sounds like you have at least a basic understanding of mechanics, which is a plus. But if you need 200+ hp to be competitive, prolly best to look for another car.

[Petros]

HI Shane,

Ice racing looks like fun, but I suspect I would have to drive a ways to find a place to do it around here. Where are you? where do you race?

I have rebuilt and tweaked the 3ac engine as much as anyone and this is what I have concluded: the head design is obsolete and really limits the performance of an otherwise sturdy engine. I am going to eventually swap it out for a 4AGE, it will cost less than doing a performance rebuild on the 3ac and it will get you more power, better economy, and way more reliability than a tweaked 3ac engine.

I am running 11.25:1 compression ratio (I use premimum fuel), a performance cam regrind (frome Delta cams in Tacoma WA, about $60 exchange). Cleaned up ports, balanced engine, lightened flywheel, spark advanced to 10 deg BTDC The only two other things I need is a weber carb and a header w/ 2 in exhaust. I have had to replace the head gasket a number of times, until I altered it to improve cooling to the head (I suggest you do this gasket mod if you keep the 3a engine, search the archives for the thread). All that might get you about 85 to 90 hp and you have pushed this engine to the point of questionable reliability. MOstly because of the 8 valve head, the ports and valves are too small. Larger ones can be installed and a major port job, but that is pretty costly way to get a bit more power. Also, Snider cams has a new billet performance cam but it is pretty expensive.

For all that effort you can still get more power out of a near stock 4age, and better reliablity. To make the 4age work you will need to alter the flywheel from the Tercel to make it bolt up to the 4age crank (8 bolt vs. the 6 bolt 3ac crank), you will need a custom exhaust (or modify a GTS corolla rwd header for the 4age), install the EFI system and fuel pump, and either cut a hole in the hood over the intake manifold or make special lowered front engine mounts. And you will have 113 to 130 hp. You want the intake manfold from the AE86 GTS corolla, if not the whole 4age engine, because it puts the throttle body in the right place for the Tercel4wd.

Another alternative is the far more common (and less expensive) 4afe. The only issue with that is you either have to cut a hole in the fire wall to make room for the aft mounted distributor, or install a distributorless ignition system. You will also need a custom exhaust, and to install the efi system The 3a flywheel will bolt up to the 4afe, and you will not need to cut the hood or lower the engine. This engine has about 103 hp stock (lots of cams and other goodies available for it), but even stock this engine has lots of torque in the low end, much more than the 4age. This is better suited to the Tercel than the 4age, and less costly to convert.

Either of these engines will give you a more modern head design. There are threads on this forum for both type of engine swaps, search for them.

Are there any rules that might limit how much you tweak your car? In most categories of racing doing an engine swap will usually put you in the category as fully modified, very expensive and powerful cars. Or do you just "run what you brung"?

[shanehutton]

-I live in Toronto CANADA and we race about 2 hours north of here.
-The paint scheme is inspired by Ken Blocks imprezza (I work for DC so I thought it would be funny) I attached a side photo.
-I am pretty handy with tools and I am not scared of doing the swap as long as I know EXACTLY what needs to be done.
-The car has actually been very competitive already because depending on the conditions my class can be won by a 3cyl Subaru Justy to a 300hp legacy turbo. The Tercel has been seems to fit right between those 2 opposites so I seem to run top 3 no matter what the ice is like. That said, I want to crush everyone next year and I figure I need 20-30HP to do that. Anything around 100HP should do me fine. I heard that the tranny in these cars doesn't like much past that anyway.
-4WD is already the top class so I don't need to worry about getting bumped up a class.
-As it stands, the car is completely gutted and has lexan windows, manual steering etc so it is pretty light.

This is my first Toyota so I am new to the engine families etc. so be kind with me.

Has anyone here tried a throttle body injector and used megasquirt? One of my ice racing friends just did it on his Chevette last week and it seemed to wake up his engine a lot. I could do that for about $300. It is either that (or a weber) + cam and DIY port and polish and a slight head shave. Does anyone have a direct link to the gasket mod for the 3a? Also, can the valvetrain take regular thrashing up to 7000rpm? (The long straight is a little long for 2nd and a bit short to bother with 3rd)

or

4AGE (I have a couple available that I can get for $200 - $300)
How hard is it to adapt the flywheel?
If I bought a header for a RWD corrola 4AGE would it bolt up and clear everything? If it needs tweaking what needs to be done?
What would I have to do to run the stock EFI? ( I assume inline fuel pump but what else? Would the wiring be plug and play? ) What do the intake butterflies get a signal from? Vacuum, electronic, throttle position??
-I don't mind cutting a hole in the hood

I'll upload some in-car video soon for you guys.

rusty vs leo.jpg

Here it is battling with a 323 GTX and a Canadian Rally Series STI (He was working on his ice technique). Came in 3rd but after 10minutes of racing it was only by about 200ft.

Rusty the ice racer.jpg

[Petros]

If I were in your shoes the first engine I would consider is the 4afe from the '88 and newer corolla, it is fuel injected and it will adopt easy, and they are common and inexpensive. About 103 hp, EFI and good wide torque curve. You will need to make a custom header, though it might be possible to use the standard exhaust manifold and make a new head pipe to get past the steering gear box (with the manual steering you have a bit more clearance). Cutting a hole in the firewall for distributor clearance is not likely a big issue for a car stripped for racing. here is the thread on the 4afe swap:viewtopic.php?f=2&t=3137&hilit=4afe+swap

Converting to EFI is not that bad, cheapest way is to use the stock ECU and just wire it up per the factory wiring diagram. Or you can spend more and go with mega squirt. And you would need a high pressure fuel pump, or adapt the corolla fuel tank into your car (with the fuel pump in the gas tank). The best way to get everything you need is find a junk/wrecked efi corolla as a parts car and cannibalize it for parts, you will have everything you need.

If you are going to stay with the Tercel 3ac engine it will be the easiest to improve, but your up side power will not be as good. The TBI conversion is a better way to go I think, than the weber, it costs less too. Use the Delta Cam performance regrind, resurface the head to raise the CR, clean up the ports, install a header and open 2" exhuast. Along with a rebuild these should only cost about $600-700. I would also lighten the flywheel and have the engine balanced. You can get by with the new stock valve springs. Do the head gasket mod shown here: viewtopic.php?f=2&t=4044&p=30186&hilit= ... ion#p30186
With the gasket mod you can use a standard gasket, the copper was unnecessary once I got the head to cool more evenly.

The 4age is the ultimate engine for these cars, they can be tweaked to big hp (170+), but they present special problems. Mostly the flywheel uses 8 bolts, rather than the tercel 6 bolt. You need the tercel flywheel so it will mate to the trans. It might be possible to either mate the 4age head to a 4afe block (which uses the same 6 bolt pattern as the tercel flywheel), or try swaping out a 4afe crankshaft into an early 4age engine block. The later 4age engines went to larger bearing journals so it would have to be an early one 1983 or 1984. To alter the tercel flywheel to bolt on the 4age crank properly takes proper tools and skills that are beyound the typical home shop. You have weld the holes up, than machine the correct bolt pattern into the flywheel. This is not newbie stuff, most shops will screw this up. A rwd 4age header has to be cut and welded to clear the steering and foot well, it does not look too bad for a typcial muffler shop to do. You can read the thread about the 4age swap here: viewtopic.php?f=2&t=4044&p=30186&hilit= ... ion#p30186

[shanehutton]

I just spent the last half hour reading a swap thread and I am starting to think the TBI 3a is the way to go. I would be REALLY happy with 100HP but anything over that is overkill. I don't think I am going to get the 3a to 100 but 80-90 seems do-able and nothing I plan on doing should hurt reliability should it?

The plan is going to be:
-TBI + megasquirt
-Just a general DIY port and polish for the head and intake (Any performance robbing issues to address in particular?)
-Shave the head (How much should I take off the head? I don't mind using 97 but I don't want to get stuck using race gas.)
-Lighten flywheel
-Delta cam + valve springs (Is there a better valve spring I can use or is a fresh stock set the best option? Do I have to go OEM or is any stock replacement set good?)
-Header (are there pre-fab units available for the 3a or do I have to get one made?)
-Head gasket mod (Thanks Petros)


Is there anything in the drivetrain I should look at while I have the car apart? driveshaft bearings etc?

[Petros]

sounds like a good plan.

you usually raise the CR by .25 for each 0.20 you shave off, you also raise it that much if you go 1.00mm (0.040") oversized pistons. Sealed Power makes flat top pistons for this engine, which also raise the CR by about .25. So if you use flat top pistons, 1.00 mm oversize pistons (requires overboring the block), and take 0.040" off the head, a 9.5:1 cr will got to 10.5:1 (which will run fine on premium pump gas).

You should also consider switching to the 4ac engine, exactly the same engine except more displacement, it bolts right in. And they are cheap. And the same performance parts will fit on it, such as the Delta Cam regrind.

I am not aware of any aftermarket valve springs, some cleaver could likely find something that would work but you do not really need it, the Delta cam regrind does not need it, and unless you want to rev the engine real high, there is no reason. the stock valve springs are pretty durable. I happen to had valve springs from three engines (all used) and I measured the longest ones from the 24 I had and used them. You should also replace the exhaust valves on your rebuild, the intakes can be reground, but the exhaust do not hold up well at all, I have burned several reground exhaust valves. The exhaust valves are not costly, any quality brand will do, no need for dealership valves.

Someone made a header for this engine (which also fits the 4ac) and it shows up on Ebay every once in a while. They likely have not been made for some time, so who ever is selling them on ebay is listing them whenever he finds old inventory somewhere. They were a pretty good buy at about $150. You can have one made too, but unless you find a home shop type welder that likes making headers it would cost a lot to have a custom header (like $800-900). If you can weld you can make one for under $100. yourself. THis is where having a buddy that is a good welder would be useful. Otherwise use the stock exhaust manifold and just make a 2" system from the head pipe back.

The drive train I think is actually pretty durable, keep good gear oil in the trans and rear diff (I suggest 50/50 mix of quality gear oil and synthetic gear oil-all synthetic does not shift well in these trans-too slippery). If your u-joints are good it should be fine. There rear drive train from a GTS corolla or a Corolla all-track is heavier but similar enough so it can be made to work (the rear axle is the same width, and has the same mounts as the Tercel4wd rear axle). Though I doubt you will need anything like that for ice racing.

I would suggest KYB gas filled struts front and rear, you can get stiffer springs but they all raise the car. Not likely stiffer springs will be an advantage on smooth ice, and you want to keep the CG low (which is already kind of high in the Tercel). If you want to lower the car, and stiffen the springs a bit, cut one coil off of each spring.

If you need better brakes check out my thread on doing a brake up-grade. the MR2 master and vented disks and calipers from a '92 or newer Tercel really improve the braking power. Not sure that is useful on ice either.

This sounds like a fun project, keep up dated on your progress.

[Neu]

Hey, If you could message your address to me I can forward it to Synth, and he can send you a big Tercel4wd.com sticker, if you'd want to throw it on your car. That'd be pretty awesome, along with pictures.

[animeracing]

You can swap in a 4A-GE, but eventually it will destroy the light-duty 4WD drivetrain under racing conditions. It isn't made for the sort of high-speed use that you find in AWD cars like Subarus.

The 3A isn't too bad, and as pointed out in multiple threads, it has potential when you get rid of some bottlenecks and bring it up to 3A-U / 3A-SCV specs. Thing is, without a lot of free parts and labor, it gets past the point of diminishing returns real quick, and so is only for those with more money than sense or a desire to be impractical.

A 4A swap (or boring out the 3A to 4A specs and using 4A pistons) would give a lot of benefit with no compromises or issues.

-Weber 32/36 - Big improvement over the stock bottleneck carb
-Throttle body injection with megasquirt - Eh, not usually worth it
-More aggressive cam (source for the cam?) - sure, a regrind or performance cam for the 4A is your best bet
-headwork (is there a bottleneck somewhere) -port and polish should be all you need, cleaning up the intake as well, maybe a 3-angle valve job.
-Is there anything else worth looking at? -exhaust. Either throw on a 2" in/out performance muffler, or remove the muffler altogether for track use. This makes it a dog to drive around town at low RPM, but with enough air and fuel flow, it packs a better wallop at 3000-5000 RPM where the big torque and HP is. You might even go so far as to have a mandrel-bent exhaust put in.

As for headers, have to go custom. The pacesetter header that was available is absolute crap. Pay no attention to the idiot that keeps putting it on ebay and various sites for hundreds of dollars. Even back when it was ~$250 retail it was a horrible product. The factory exhaust manifold is actually a pretty ok 4-into-1 design for mid to high RPM power, even though a 4-2-1 header would do better for midrange RPM use.

You can just grab a bunch of aftermarket replacement head parts (valves, springs, etc.) off RockAuto on clearance to get better high RPM performance.


My suggestion would be to have fun with it and keep it reasonable for what it is. Motorsports and racing in general loses a lot of the fun when it turns into the money wars and you're dumping dough into a money pit just to try and keep up with more modern vehicles that are already ahead of you just by their newer technology and design. Sure, a hi-po Tercel wagon is cool and different, but you can get an AWD Celica or Eagle Talon/Mitsubishi Eclipse for less than it would probably cost to make the wagon truly ultra-competitive. If you have access to an auto shop and a bunch of donor vehicles for parts, thats different, but still a lot of time and work.

[Petros]

Do not attempt to over bore a 3a engine block to 4a spec, there was a service bulletin to check for water jacket break out when overboring the 3a block only .040", and if you did the fix was to sleeve the engine. It is doubtful you can take it all the way to the 4a bore dia., better off starting with a 4ac engine, they are cheap and plentiful, and I think they have a larger carb too.

[animeracing]

Depends on the engine. Some 3A's and even 4A's had thinner walls or something, but then again if you have one of those you're better off finding out when boring it out . Not that I disagree, swapping over to a factory-bored 4A would definitely be preferable or even using it as the basis for a build rather than the 3A.

The only difference between the 3A and 4A (other than the cosmetic/functional block revision) was the bore size. Even the heads were the same. The too-small Aisan carb was the exact same as the 3A, too. If the 4A carb was larger, we'd all have been throwing them on the 3A for the past decades.

[Petros]

The 4a and 3a carb are not the same (even if they are the same size). I had a chance to take a close look at a 4ac carb in the local yard last Friday. The connections are all different, they have vac ports in different locations. Not that you could not make it work, but I decided there was too much difference between them to make it worth the effort. There are even differences in the 3a carb from year to year, but not that much.

List member Tercel4wdrules has the idea to fit a 20R truck carb to the 3ac. They are similar in design but the 20R carb is larger, and it would be cheap (about $15 from my local Pull-A-Part). Has anyone tried that carb swap yet? They have all the right connections so you can make it appear smog compliant, and likley you could pass both visual and exhaust inspection for areas that require testing to register your car.

[shanehutton]

The car already has a straight pipe going from the manifold and dumping out just ahead of the rear wheels.

I "think" I have decided not to do the 16V swap as I just got my hands on an E30 BMW track car for the summer

I am still keeping my eyes peeled for a 4Ac long-block though. The only real question now is to megasquirt or get a webber. I think that will just come down to how cheap I can get a Webber for. I'll keep my eyes peeled and if I can't find a used one then I think I would rather spend the $300 on fuel injection than a carb.

Can I use ANY Webber 32/36? There seem to be a lot of different versions and ebay lists them with many different car makes and models. Are they all the same? Is it just different ways of operating the choke?