GReat engine.....maybe?

[Foolish86]

I saw something suggesting a pieced together engine. It said they had a BLack Top 20V on and a 4AGZE crank (steel). But it also said it had the 4AGZe supercharger. ANyhow.....my question is, how would you go about programming an ECU for VVT and a supercharger?

[toyotaspeed90]

lol... that's a BS post.... he would need a custom manifold, as the intake manifolds aren't the same on the smallport or on the bigport as they are on the 20V..... along with the headaches of trying to fit the 5th valve into a gze piston setup......

[Foolish86]

The 4AGZE and the Black Top 4AGE have the same block...both are seven rib, and both have the larger journals than the 87 onward. Only the 4AGZE has a larger clutch and flywheel; but the clutch and flywheel are interchangeable between all 4AGE's. SO....he used the smaller flywheel of a AE86 so that it would fit under a T-50 bellhousing. And he said he just used the crank, block and supercharger of a 4AGZE, and using the Black Top for everything esle. What my question is, Could you get someone to reprogram the ECU for VVT and a supercharer?

[toyotaspeed90]

i don't think you understand...... a 4agze has a special intake manifold made only for the supercharger.... no 20V has the same intake manifold setup as either of the 16V's do (which are the only platforms the supercharger came with)...... hence, a 4agze supercharger and manifold won't bolt up to a 20V head.... and how can he be using a gze shortblock and not be crushing that 5th valve?

[micro214_kp61]

Originally posted by toyotaspeed90
.... and how can he be using a gze shortblock and not be crushing that 5th valve?

i've heard a lot about this subject and still don't know who to believe. some people say "it clears" but a lot of people like you said "it'll hit". can you please explain this further more? thanks!

Foolish86... a friend of mine informed me about a guy he knows that reprogram stock ECU and can make it reprogrammable. i've never met the guy personally but i don't this friend of mine bullshitting me though. if not, i gues there's always the bling-bling aftermarket ECUs, hehehehe!

[Foolish86]

ALL 4AG'S HAVE THE SAME BORE AND STROKE. With that said, the AE111 pistons (Black Top 20V) can put on a 4AGZE crank. They also have idenical blocks. I was metioning using the 4AGZE block and crank because it would be cheeper to buy a entire 4AGZE engine, and use the block, crank and supercharger. Then you would have to buy a BLack Top 20V head, which will bolt on the gze block because.....THEY HAVE THE SAME BLOCK! The 4AGZE crank is steel while the rest i believe are cast iron. Anyhow, it would be like running a Black Top 20V with a supercharger and a steel crank.

Toyotaspeed, i understand what you are telling me....but i think with some custom fab. it would work. I'm not trying to be a smart ass, and just tell you are wrong and i am right. If you don't think it will work please tell me.

So what do you guys think?

The pistons won't hit because they are the OEM pistons for a AE111. Also they won't hit because the gze crank is idenical to the AE111 crank. The two also have the same length rods, only the late model gze has lightened forged rods.

[hachi_slow]

Foolish86: Just curious - how many pounds of boost will you be able to run with that seeing as how the AE111 is designed with an 11:1 compression ratio?

[micro214_kp61]

Originally posted by Foolish86
ALL 4AG'S HAVE THE SAME BORE AND STROKE. With that said, the AE111 pistons (Black Top 20V) can put on a 4AGZE crank. They also have idenical blocks. I was metioning using the 4AGZE block and crank because it would be cheeper to buy a entire 4AGZE engine, and use the block, crank and supercharger. Then you would have to buy a BLack Top 20V head, which will bolt on the gze block because.....THEY HAVE THE SAME BLOCK! The 4AGZE crank is steel while the rest i believe are cast iron. Anyhow, it would be like running a Black Top 20V with a supercharger and a steel crank.

i'm confused! if the ZEs are a lot common, how is it gonna be cheaper to buy just the BT 20V head (isn't it harder to get this than a AFM ZEs)? i've never seen anyone selling just a head. isn't it better to buy a whole BT 20V, install it and then later on boost it. hachi_slow made a good point, and you're worried about the cranshaft but not with the ohter internal parts which are much lighter (meaning not meant for boosting but for high revs) like the pistons. the AE111 pistons are not really meant for boosting. you'd be lucky if that motor last for a month with even a 5psi of boost and driving it hard. i still don't understand why you have to make the BT boosted, it'll be much much cheaper to build-up the 16V ZEs with much better result. but i you have the cash then goodluck!

toyotaspeed90... i'm still curious about the clearnce issue! thanks..

[Foolish86]

SUPPOSEDLY, the gze has alot of lowend torque, while the BT has hardly any....so put the two together, and i would have torque all the way through all the gears.

And cash isn't the problem, my dad is helping me pay for it. He is helping me because he bought my bro's car for like $5000 and he bought mine for $300...so he is giving me like $2000 to to do it...on top of the $2300 i already have.

OH yeah...and i wouldn't be running stoke AE111 pistons, i would run OEM ones. not sure on the brand yet.

[Kwanza]

I guess I'll be the one to back up toyotaspeed90 as I've done so in the past (on other webboards)...

The S12 supercharger will not bolt up to the 20V blacktop head without some sort of adaptor plate. The intake ports are different. Difficult to do, not to mention ditching the ITB's isn't the best idea...

As for the crank swap... no reason for it. The crank has little to do with boost-ability and/or clearance issues... and the 20V crank is also forged steel... as are all 4AG cranks. The major differences between the 20V block and the 4AGZ block is the rods and pistons with only minor differences in the crank. I'm not sure from your description exactly what you're doing... but just mention it... the only major differences between the 4AG cranks is the larger journals in the 7rib blocks... aside from that, all of the cranks are nearly identical...

For clearence issues... there are 5 valves in per chamber in the 20V head and only 4 flycuts on the 4AGZ pistons (if those are used). The 20V head might not clear the 16V pistons because of the lack of proper flycuts in the piston head for the 5 valve design. I don't see the 20V pistons being used in a forced induction application either, because of the high compression, which will cause all sorts of major fueling, pinging, and computer problems.

For the original question... VVT will probably be eliminated unless there is an aftermarket system that can be tuned to controll VVT actuation. An aftermarket programmable ECU is MANDATORY for a 20V supercharged set-up. As of current, the parts you listed will not work without some serious modifications, custom fabrication, and some very serious tuning. I'm not saying it's not possible, but i'm gonna say not very practical. Why not simply do a 4AGZE swap? Anyway... if you have further questions... go ahead and shoot them out.

[4Aaron GE]

One thing though: The GZE has a lot of low end torque, because it's got the SC12 on it. The 20Vs have a lot of high end torque because they've got the 5th valve and high compression. Just like Honda's B16s do. So by using the GZE shortblock, you've just removed the high compression part. Making it very difficult for the cam timing to do its job. This in essence should probably kill your top end.

Then we come to the problem with using the SC12. Even on a stock GZE, you will notice that the engine pretty much runs out of steam at high revs. This is because the roots design of the SC12 causes it to become very inefficient at about 4-5k rpm. Now, having boost might allevieate the problems of low compression killing your top end power, but the intake charge at that point is VERY hot, even after the I/C. This may cause pinging, or other problems with your engine.

Now for the physical problems with doing it. What Toyotaspeed90 means when he says the intake manifold won't fit, is exactly that. It phsyically won't mate up with the intake ports on the head. You won't be able to use the 20v intake manifold with the ITBs either, because the GZE setup goes TB -> SC -> IM. It makes it next to impossible to use that setup on the GZE, since part of the SC12's mounting bracket is part of the intake manifold. Now, I know that for engines where the TB is attatched directly to the IM, you can get or make IMs for relatively cheap. However, since the IM for the SC12 feeds downwards from the I/C, and has brackets for the S/C, and possibly also the pipe for the TB (I'm not going outside to check, it's 3:30am), that's going to be one damn expensive manifold.

And is there even an affordable aftermarket system that will handle VVT-i?


edit: so okay, it was several things.

[toyotaspeed90]

ok..... i have heard the 5th valve will clear a stock 16V piston.... however, there is also a lot of talk that the 5th valve actually does the engine no good, and that the 16V head was designed well enough that the 5th valve is unnecessary.

the supercharger setup is pretty much exactly as 4aaron ge stated...... it's complicated to say the least, and trying to make that work with a 20V head would be ridiculous. If you do a 4agze swap and feel you need top end power, then you should decide on one of 2 things:

1) twincharge it
2) find an n/a intake manifold, sell the s/c, and turbo it.

both are feasible (believe it or not) options which have been done (moreso for the latter).

in any case

[micro214_kp61]

Kwanza/toyotaspeed90... thanks!

[Foolish86]

thanks guys....since there the top end torque will be eliminated anyhow...there is no reason for me to use a 20V head.

Sorry if you guys thought i sounded like a smart ass....i really am. You guys know WAY more than i do.

Anyhow....no more plans for a BT 20v gze!

[Alpha]

Wow, this is a good thread, I learned alot from it. I think this should be stickied