[mrstu]

Well my white s/c has been slowly losing coolant over the last few months randomly stalling out, with a surging idle, and slightly smoking out the tailpipe. I replaced the radiator with the help of MikeMo (Thanks!) and attempted to bleed the coolant, but still the problems persisted. I was never able to fully bleed the air out of the coolant despite my best attempts.

The car never overheated but I noticed a moaning sound and a loss of power messing around on the highway one day and my temps rose steadily toward hot before I shut the car down and let it cool off. Just driving around town the car was still losing coolant but drove ok, with no noticeable loss of power. I did a compression test and the middle two cylinders were about 25psi off.

About a week ago, we got around to removing the head. I wasnt really sure what to expect, however already I purchased another s/c car just for its longblock, expecting the worst.
The hg indeed took a large dump failing in several locations. There was coolant everywhere inside the motor. But the pistons and cylinder walls were immaculate. No signs of detonation at all

So with this good news Ive decided to take the funds Ive set aside to tear down my motor and rebuild it, and splurge on some projects that Ive been thinking about for some time now. I have no desire to turbocharge the car. I have a gen3 swapped 93T that made 425 hp on ATS's dyno, and I'd like to keep all my turbo aspirations confined to that platform. I absolutely love the supercharger in my mk1. I would never want to lose that aspect of the car. Already I have the NST pulley kit, GB, TRD header, and a fujisubo exhaust. I am going to install the WEB 294 cams (their most mild cam) that I purchased last year. I could have gone more aggressive with my cam choice, however the research Ive done indicated to me that many people select a cam much to large for a supercharged application. Im leaning towards purchasing a TRD headgasket and ARP headstuds will def be installed.

Im open for suggestions with my set up, and well as any advice anyone has for me. Ive seen a lot of people talk about the 7agze/sc14 but few are actually running them. The car should be back together in the next few weeks as Im waiting on parts to arrive. Please lmk what you guys think ....

Heres a pic of the car just for reference
When i first got it...totally stock

 

[mrstu]

This was my favorite pic of the car on the enkei rs-5 rims

And a nice shot of the perfect matching 89 spoiler i found on a car in the junkyard

One of the sc at sping fling a few years back

mods include....
TRD Gymkhana race springs
koni yellows
89 rear strut housings and sway bar
TRD header
Fujitsubo exhaust
grunt box
NST pulley
Web 294 cams
fidanza cam gears
na tb
custom ic and piping

 

[KennyBoBenny]

Looks like a good project. I'd actually be interested in some SC14 brackets for my spare one.

 

[johnnybusa]

what is a sc 14 and where is it from?

 

[2fas2c]

the SC14 is a larger displacement supercharger than the SC12 found in 94-97?? Toyota Previa. It can be adapted to the GZE but requires quite a bit of custom work.

 

[Turbowned]

If you can find a good SC14 for $1-300 I say do it! It's not that much work to adapt it.

 

[mr2_reverend]

the SC14 is a larger displacement supercharger than the SC12 found in 94-97?? Toyota Previa. It can be adapted to the GZE but requires quite a bit of custom work.

This I did not know...

Wasnt the Previa a minivan? What in the world was Toyota doing supercharging a minivan?

 

[yoshimitsuspeed]

This I did not know...

Wasnt the Previa a minivan? What in the world was Toyota doing supercharging a minivan?

AWD and supercharged.
They were planning on being king of minivan class of drifting and rally events.

http://www.youtube.com/watch?v=_meHP_ZrliU

Only messed up part is the SC edition was only available in automatic. How dumb is that?

 

[jkprow]

Only messed up part is the SC edition was only available in automatic. How dumb is that?

It's absolutely criminal.

Some buddies and I were about to give some guy a couple of guitars in trade for a RWD Previa and do the SC swap with the 5-speed. Were gonna cut the roof off, turn up the boost and have a mid-engined SC drift missile van; you know, the American dream. But we're poor college kids and things came up. Someday...

 

[oldeskewltoy]

So with this good news Ive decided to take the funds and splurge on some projects that Ive been thinking about for some time now.

I absolutely love the supercharger in my mk1. I would never want to lose that aspect of the car. Already I have the NST pulley kit, GB, TRD header, and a fujisubo exhaust.

I am going to install the WEB 294 cams (their most mild cam) that I purchased last year. I could have gone more aggressive with my cam choice, however the research Ive done indicated to me that many people select a cam much to large for a supercharged application.

Im leaning towards purchasing a TRD headgasket and ARP headstuds will def be installed.

If I may.......

The 4AGZE was and is fine with stock headbolts, and a stock head gasket - worked great from the factory for YEARS. The ARP headbolts is in no way a minus except in cost, and in need... the TRD gasket requires both the head and block to have perfect mounting surfaces, without perfect surfaces the TRD gasket can leak. The TRD gasket also raises compression by about 4/10 of a point, but if you machine the head and block for it to mount perfectly, the compression is raised even more.

A thought... deck the block(cut the top of the block) 4/10 of a mm, and use a stock head gasket. This gives you the perfect sealing of a stock gasket, AND you get the compression bump.

The Web 294 is a PERFECT S/C cam, it has steep ramp rates, so although the overall duration is only 6 degrees more than stock cams(246 vs 240*), the duration @ .050" is MORE then all of the other 256 type cams(220 vs 218). They also have more lift then all the other 256 type cams - 8.18mm

* - stock (pre 1988) cams 240 total - 204 @ .040"
.....stock (post 1988) cams 232 total - 198 @ .040"

Quick note on valve springs... the Webcams were specifically designed so that their lift + clearence = max a stock 4AG spring can accept before coil bind. I've personally built a 4AGE with those cams, and stock springs. The engine is nearing 80k miles on it :smile: With that said... the Toda springs are less costly, but do add some more tension to the valve train.




Not sure of what your budget is... but I would recommend some head work. Intake side needs very little, bowl and seat work mostly. The exhaust side could use some porting, but the real key for power for you should be inside the chambers... deshrouding the chambers will allow you to run more compression, or ignition timing without worrying about ping/pre-ignition.

A perfect chamber + boost = wonderful thing :thumbup

 

[mrstu]

thanks for the advice ost. I appreciate hearing from others with more knowledge/experience than I have... thats exactly what I was looking to hear in regards to my cam choice. :thumbup
As far as the motor build, everything was going along smoothly, just got my e-bay core in, and waiting for the rest of my piping to be fabricated until today when I rolled up to the garage and saw a corolla on a trailer. The owner is a friend, and he was looking to sell the car. The shell was immaculate with many nice aftermarket parts, but I was really interested in what was under the hood. The owner was not very familiar with 4a's, but he began listing the specs of the motor off to me and really got my attention. Its got a 7a block, sc pistons and a silver top head, with a ported t25 turbo. The owner believes it will be good or around 300hp
But as Ive mentioned in the past, I really dont want to run a turbo in my mk1. at all. like zero desire. So I guess my question would be, since I believe I would not be able to run the 256 cams in the silvertop....what the difference in the setups would be if I ditched the turbo in the corolla for my sc12/14 and threw that motor in my car vs my current plans. Id love to hear some opinons.

 

[mrstu]

No one? Its decision time and im still indecisive

 

[fastrax203]

Assuming you're buying this Corolla, your options are (?):

A - Remove the engine in the corolla, remove the turbo setup, install SC14, install motor in MR2.

or

B - Proceed with your current plans

I'd go with B. At least you know you'll have a fresh engine.

 

[mrstu]

The corolla options would basically include buying just the motor and using the 7a lower end with sc pistions already installed and running my sc head with the web cams (or just running as is with the st head) but removing the turbo kit in favor of the sc. Im not sure how much of a difference the added displacement would make in a supercharged application, if it would be worth the added effort. Or even which head to choose at this point. The stock st head or my sc head with the web cams. Like i said Im very indecisive atm
Or just continue as planned....

 

[oldeskewltoy]

I'm sorry I didn't respond earlier... I've been working a clients head.

before you run down someone elses rat hole.......

How much is this other engine going to cost? Has it run yet? Who rebuilt it? What parts were chosen/used in the rebuild?

A properly built 7AGZE will make mind blowing torque... at very low rpm. Keep the Web cam, if the compression and squish are correct, I see torque #s exceeding 175 @ about 1800-2000 rpm, and @ max boost torque should exceed 220#/ft. (would require a properly built 16V head with O/S valves)

To put that in perspective.... a stock 4AGE plants about 90-100#/ft maximum

 

[mrstu]

The 7A/st motor supposedly was put together by a master toyota tech but has never run. There are no cheap parts on the corolla if that is any indication of anything. Everything is pretty much top of the line on the car. He is selling bc he ran out of money to finish the car. Im looking at an added $500 or so to go with the 7A bottom end.

 

[Turbowned]

Well, without receipts or a build sheet that motor is kind of a crap shoot, but it sounds pretty nice in theory. Tough call. It happens to be similar to the engine I want to build, except I'll be running a blacktop head.

 

[mrstu]

the only good thing in regards to a major engine failure is that I still do have a spare gze block just in case

 

[mrstu]

Few updates to report. I ended up trading for the 7a Block. Im going to run the sc12/gze for now tho. I plan on getting the set up dyno'd and enjoy it. Then in a year or so go ahead and upgrade to the 7a block and have the set up dyno'd. Then install the sc14 and have it dyno'd once again. In the meantime, this is what Im working with

 

[Turbowned]

Looks good to me! Nice I/C plumbing, that should free up some power. The SC12 looks haggard on the outside, but it's what's on the inside that counts.