Hey everybody!

I need some help. I'm looking for aftermarket potential on the 20v silvertop. Something other than "Blitz turbo" and "why not blacktop." Because I cant afford the Blitz turbo and the blacktop is weak IMO after doing research. I need something like internals, manifolds, etc. Any help is appriciated.

-Ti

There's a huge aftermarket for all 4A-GE motors, but most stuff made specifically for the 20V ones can't be found cheaply in the US(Well, not cheap at all, but even more expensive in the US.) >>

For pistons, you can use 4A-GZE pistons, but unless you have them cut for the indent for the extra valve, it turns the motor into an interference motor, where if the timing belt breaks your pistons will hit your valves and do severe damage.

The silvertop's block, crank, and rods are equivalent in strength to the AE101 4A-GZE's block, crank, and rods. Some people say that the rods are exactly the same, but everyone always argues that they're not the same, but very close and equal in strength.

For exhaust manifolds, anything that fits a 16v 4A-GE will fit a 20v with modification so that the outer bolt holes match up. Nik is working on fitting a Honda B-series turbo manifold to a 16v 4A-GE flange...that might be a good option for a turbo setup. You will most likely have to go custom on the exhaust manifold.

The motor is really good for boost...the stock head gasket and such is fine for mild boost. In stock form at 5-6 PSI with exhaust, I've seen numbers from 185 whp to 215 whp. The key is tuning. It's very important with any turbo setup, but more so with a motor running 10.5:1 compression.

For more boost and more reliability, 4A-GZE pistons are a good upgrade. They bolt in and lower compression to 8.0:1 or 8.9:1, depending on which pistons you get.

Also, when running more than a few pounds of boost, a new intake manifold plenum is required, as the stock unit will leak or be destroyed by lots of boost.

You'll most likely want to go with a standalone EMS if you're going turbo. Many people go with Megasquirt(and a Ford EDIS-4 ignition setup) for a low-cost solution. The AFM sucks for boost, and you need to be able to precision tune everything(and you'll want to get the car dyno-tuned professionally) if you want a reliable setup.

But yeah, the silvertop is a great motor and is excellent for boost. I considered boosting mine, but I've decided to invest in a new camera and stuff instead.

If you've got more specific questions, post 'em up if they haven't been answered through searching.

By the way, if you do put in the 4A-GZE pistons, you might as well upgrade to a metal headgasket while you're at it.

And here are some turbo manifolds built for various 4A-GE engines...it'll give you some ideas as to what your options are.

Were you looking to go NA?

If so, find a nice header, have the head worked, find some blacktop ITB's (they are slightly larger) and run them open with a megasquirt.

If it's not for a daily driver, raising the compression to 11:1 wouldn't hurt. >> I also wouldn't be surprised if the black top had more agressive cams. >>

-FallenHero+Apr 25, 2005 - 5:56 PM

Cams are the same between the two from what I've read. The internal differences lie in the lighter internals, and there are also different shaped intake ports on the head that flow better.

Thanks for all the help guys. I'd like to run about 180-200whp. If I can do that N/A I will. This is a project of mine, and I dont have thousands to spend on an engine. It's more or less also going to be a city daily driver. Not actually driven daily, but its not just going to see the tracks. Also, do you (fallenhero) really think its okay to run the ITB's open without filter? And onto that subject (chris), where would I find a new intake plenum if wanted? I really dont want to go custom tooooo much. Any more ideas are much welcome!

-Ti

-turboinduction+Apr 25, 2005 - 7:29 PM


well, to me, open is a relative term. >>

By "Open" I would build some type of filtration system that had zero restriction.

And coom's right, I had forgotten about the minor head differences (silver to black) Also, if I'm not mistaken, the blacktop has a more domed head design. But hey, if you are thinking about milling the silvertop head for compression,,, how much of a dome can you have?

I myself am in the process of locating a 20v head. I have all but decided to use one of them on the 7ag (which has been in the planning stage for more than a year now)

I think I have pistons and rods, but I cannot get confirmation if they will fit.

Oh, and I am not going purely NA. I plan to run 10:1 - 9.5:1 compression. That will give streetable performance while allowing me turbocharged possibilities.

You can't easily get 180-200 whp N/A out of a 4A-GE without spending thousands. With your budget, you're better off boosting, but I suggest you swap the motor into the car and then decide if you want more. The motor is pretty quick in my car, and in a lighter RWD platform, it'd be even faster.

-Coomer+Apr 25, 2005 - 11:15 PM

yes chris, first things first - lol

I'll keep you posted

-Ti

Youre working on a AW11? I yern for such a project. >> Best of luck to you.

-FallenHero+Apr 26, 2005 - 9:39 AM

ah, yes I am. You guys know me. I couldn't stay away from Toyota THAT long. Hell, its been almost 2 weeks without my T in the driveway. Sheesh.

Just bought 2 1987 mr2's. One auto (roommate bought it) and other manual. But the rods and heads are shot in the manual. So, its time for something new via the 20v silvertop. Now heres the kicker. We got both cars for .... 613 dollars!!! Weee. I love ebay.

And for any AW11 16v/20v people... I found a guy who makes VERY VERY nice turbo manifolds for our upsidedown platform, along with downpipes and heat shields.

Check out his website

-Ti

This post has been edited by turboinduction: Apr 26, 2005 - 8:24 PM

nice. >>

Build yourself a smallport 16valve and boost it. It will save you headaches... and will be much easier to work with.

-FallenHero+Apr 26, 2005 - 9:25 PM

it would cost me the same to buy pistons and rods (if i can find them) as it would just to purchase a 20v. And right off the bat i've got a 50hp increase, plus uniqueness as I've never done a swap. Something to learn.

-Ti

what would you do for intake on a 20v boosted?

-Ti

-turboinduction+Apr 28, 2005 - 12:04 PM
You need to build a custom intake plenum... basically a little box to cover the throttle bodies. The stock one is pretty flimsy. The intake plenum is the box that covers the throttles and has "4 throttle" written on it... just in case you're not sure... ;]

IMO, the 20V is a better boost engine because everything about the head design is geared towards induction. With 3 intake valves, it has more overall valve surface than a 16V and it has ITBs... the ultimate in EFI intake systems.

http://www.todaracing.com.au/toda_home.html they have almost everything for the 20v engines!!!! go for n/a!

-Kwanza26+Apr 28, 2005 - 9:26 AM

Intake plenum? ITB's? 4 throttle? What ever do you mean?

>>

I figured I'd go custom, but I was hoping for the "oh ti, geez... heres a link to buy a new stronger one for 20 bucks!" Gotta try. Also, with your 4AGE knowledge... what do you think max boost on stock internals. I'd figure on a silvertop, I'd be safe at 6/7. But I'm curious if 8-10 has worked for people. Any input is much appriciated. >>

-Ti

-maikl+Apr 28, 2005 - 9:48 AM

todaracing.com (usa site) has nothing for 20v that I can see. todaracing.com.au doesnt seem to have a Toyota section up yet? Any help?

-Ti

-turboinduction+Apr 28, 2005 - 3:59 PM
=P

Silvertop has nearly identical bottom-end parts to the 4AGZE. The rods are slightly reworked and lightened on the silvertop, and it has 20V pistons... but most all else is the same. With 4AGZ pistons, I can see safe boosting at around 12-15 psi. With stock 20V pistons, I wouldn't try more than 8...

Also... Todaracing.com does list 20V stuff. I think they call it AE101/111 5 valve or something like. They have pistons, cams, cam gears, etc.

-Kwanza26+Apr 28, 2005 - 10:13 AM

Oh boy I'm blind. I have to scroll! WHAT. I found the 20v stuff on toda.

Now more questions!
With the swap of the GZE pistons into the 20v, what do I do about the 5 valve head on 4 valve pistons? I'm curious on whether toda will custom make lower compression pistons for the 20v. They obviously boosted the AE101 upto 11.8, so I think they should go down too. I WOULD LOVE 15 PSI ON A 20V. That last statement even deserved the Natalie caps lock tradition.

-Ti

This post has been edited by turboinduction: Apr 28, 2005 - 3:48 PM

Like I said earlier, the pistons work, they just turn the motor into an interference motor. You have to have them machined if you want them to not hit the valves if a timing belt breaks.

-Coomer+Apr 28, 2005 - 1:30 PM

sorry Chris, I reread what I wrote. I wasn't asking a question, I was moreorless pondering my possibilites. Like "new pistons or cut pistons?.. what to do what to do... even though I did ask a direct question - I knew the answer I was just thinking outloud >>

Do you know if Toda will make custom pistons? Because they already have an AE101 kit available, just at a high compression.

Also I understand what your talking about with the belt and the pistons hitting the valves... but I've never heard the term interference motor until your first post. What exactly is that? More forward... do people run engines like this?

EDIT: I went ahead and did some research. Apparently, many companies make motors like this to cut emissions and quiet down the engine. This way the engine can be smaller, more effective, and quieter. However, with every advantage, there is a disadvantage. The timing belt doesn't even have to break, but slip causing the timing to be off just a bit. And whammo. Luck of the draw I guess.

-Ti

This post has been edited by turboinduction: Apr 28, 2005 - 3:56 PM

Hmm, you have a ton of researching to do before you begin a project like this.

An interference motor is one where it's possible for the pistons to hit the valves if a timing belt breaks. Off the top of my head, I think that some Honda motors are...I know that the B20A in the third gen. Prelude is, as my friend just had her timing belt break, so I did some research into whether it was non-interference or not.

If Toda doesn't list low compression pistons for the AE101 4A-GE, then they probably don't make them, and I doubt they would custom make you a single set...they might, but it'd cost a ton of money probably. Why don't you just get 4A-GZE pistons and have them machined?

here 20 VALVE FORGED TURBO PISTONS 8.5:1 @ http://www.toysport.com/webpages/WebUpdate...MARCH202002.htm
maybe contact
http://www.fensport.co.uk/fensportcars.htm

i saw a site some where that had 5 valve low comp pistons
but you always can buy 4agze ones and have them machines to match the valves but it probably wont be cheap

http://forums.club4ag.com/topic.asp?TOPIC_ID=94447

Slow'n'rusty in 4agclub know a lot about turbo 20valves

Good luck !!!

Claude

Toda doesn't make low-comp anything because they only do n/a race builds... ;]

Contact Drag86 from club4ag if you're serious. He can get some made for you... pretty good prices too.

http://forums.club4ag.com/topic.asp?TOPIC_ID=99156

-Coomer+Apr 28, 2005 - 2:57 PM

I do research >> I'm intellegent, but I am (was) limited to my knowledge. I really only know outside the block. I understand compression, know what cranks and rings are, etc etc. However, I really just take the motor for what it is. I couldn't put one together if I tried. I know suspensions like the back of my hand, and I know parts outside the block fairly well. I'm an electronic guru with 13 years working on computers. Now its time to further more my knowledge. Its time to learn how the internals work. Thus this project. I wont learn until I do it. And I believe that this will be a good lesson for me. It accomplishes two things. One - swaping a motor. And Two - turboing a N/A car. I came out of the DSM line before my toyota and nissan. So I understand turbos, but only since it was pre-built on the 4G block. I will do the research to complete the goals and I have another car to drive (sentra spec-v). So yes, I may sound like a 16 year old newbie wanting to swap a 3S into a 94 ST, but I am more knowledgable than that. I really appriciate the help everyone has given me. When I started this thread I had only known that a 20v existed because of Kwanza and Coomer, besides that I hadn't a clue. Business in the auto industry has been slow, so for the past week I've spent 4+ hours a day reading mr2oc.com posts, googleing to find complete 20v swap how-tos, finding aftermarket parts, and finally researching how the damn engine is put together to begin with. Back on topic, my little knowledge on engines doesn't allow for pricing. Thus my confusion with machining the GZE pistons or buying new ones. I dont have clue how hard it is for a shop to machine new heads on the pistons. Or what the cost. Or where to go, if there is any place in Central Wisconsin for me to go. So, I figure I can install pistons once in hand, so if I can just find them already made - even if more expensive, its better for me. Thats why I'm posting here. Maybe new 800 dollar pistons aren't worth it when Kwanza might know someone that can make them cheaper. Maybe Coomer knows that all it takes is 100 dollar GZE pistons machined to do the job for little money. I'm still much into my knowledge gathering stage and again, appriciate the help you guys give me. Sorry for the long post.

EDIT: Off topic question. Cams. I know what they are, but...
AFtermarket side of them. What does a longer duration and lift do for me. Obviously allows for more air to breathe in to exit. But why wouldn't you want the longest possible time then? How would I know what duration and lift I would need for a project? I really couldn't find much about them on the net other than "I put these cams in to get this effect" but no explaining on how to pick cams at all. I.E. ToySport Cams - half way down

-Ti

This post has been edited by turboinduction: Apr 28, 2005 - 9:05 PM

anyone know?

As I understand it, a higher lift pushes the valve down more, allowing more air to enter because the opening is bigger. While a longer duration keeps the valve down longer, allowing more air to enter over a certain amount of time.

I think with a big change in cam lift over stock, you need to upgrade your valve springs to handle the extra movement.

-Coomer+Apr 29, 2005 - 1:51 PM

If thats the case, why wouldn't you want to opt for the highest lift and longest duration? What your saying makes perfect sense to me, but I dont understand why there are options

-Ti