20v questions

Strictly 20valve engine related topics.

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slo rolla
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20v questions

Post by slo rolla »

Just curious I don't kno a whole lot about corollas yet but I'm wanting to do a 20v swap! From yalls experience which is a better setup the blacktop or silver top and what's all needed for the swap? Your help would b greatly appreciated!

dr.occa
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Re: 20v questions

Post by dr.occa »

the silvertop will have sturdier bottom end parts but you're dealing with MAF/AFM so no ITB coolness unless you run the blacktop ecu. the blacktop uses MAP so that's one less headache to deal with in getting it up and running. the bottom end components are smaller by comparison to the hi-comps and silvertops but it's balanced to spin easily to 8300 (later model blacktops that is i.e. 95-97???).

the blacktop for high revving NA love.

slo rolla
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Re: 20v questions

Post by slo rolla »

dr.occa wrote:the silvertop will have sturdier bottom end parts but you're dealing with MAF/AFM so no ITB coolness unless you run the blacktop ecu. the blacktop uses MAP so that's one less headache to deal with in getting it up and running. the bottom end components are smaller by comparison to the hi-comps and silvertops but it's balanced to spin easily to 8300 (later model blacktops that is i.e. 95-97???).

the blacktop for high revving NA love.

So would you suggest the 16v with itbs instead of the 20v?

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Re: 20v questions

Post by dr.occa »

it really depends on how soon you want to be up and running.

the 16v w/ ITBs is better for low mid range response and still good for top end revving. in my opinion it'll have better trq response where a lot of drivers that i'm acquainted with like it. it's just you'll need to run fuel management. noone has cracked the oem 16v ecu for ITB management without getting it chipped and reflashed. you'll need to run some sort of management even for a factory head and bottom end due to the change and increase the ITBs introduce.

with the 20v BT you'll be up and running with ITBs as soon as it's all properly installed (so long as the motor is in good health of course ;) ). if you're not happy with where the trq response is later you can introduce a change of cams or just alter the ex. cam since it'll accommodate many aftermarket 16v ex. cams.

recap:
stock 16v w/ ITBs = a little longer time and more money before you'll be up and running
stock 20v blacktop w/ ITBs = up and running almost immediately w/ factory ecu

hope that helps you come closer to deciding.

slo rolla
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Re: 20v questions

Post by slo rolla »

dr.occa wrote:it really depends on how soon you want to be up and running.

the 16v w/ ITBs is better for low mid range response and still good for top end revving. in my opinion it'll have better trq response where a lot of drivers that i'm acquainted with like it. it's just you'll need to run fuel management. noone has cracked the oem 16v ecu for ITB management without getting it chipped and reflashed. you'll need to run some sort of management even for a factory head and bottom end due to the change and increase the ITBs introduce.

with the 20v BT you'll be up and running with ITBs as soon as it's all properly installed (so long as the motor is in good health of course ;) ). if you're not happy with where the trq response is later you can introduce a change of cams or just alter the ex. cam since it'll accommodate many aftermarket 16v ex. cams.

recap:
stock 16v w/ ITBs = a little longer time and more money before you'll be up and running
stock 20v blacktop w/ ITBs = up and running almost immediately w/ factory ecu

hope that helps you come closer to deciding.

Yeah that really helps a lot, I think I'm gonna go with the blacktop, but is there anything special I'll need for the swap, mounts, what transmission and stuff bc I have an SR5?

dr.occa
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Re: 20v questions

Post by dr.occa »

slo rolla wrote:...I think I'm gonna go with the blacktop, but is there anything special I'll need for the swap, mounts, what transmission and stuff bc I have an SR5?
you can try and stick with your sr5 tranny (so long as it's 5 speed) and just be sure to make a heatshield to protect the soft line for your clutch slave cylinder from the header collector(s) or else you'll melt it and catch things on fire.

wiring will be a bit different and somewhat tricky from a GTS. w/ the GTS a lot of the wiring is there for the ecu batt and B+ connections. the COR (Circuit Open Relay) is not difficult to connect to neither will wiring in an electric fuel pump. i'm not sure how much larger the GTS fuel feed line is than the SR5 but the return lines are comparable between the 2. if anything, i'd say go with a braided line from the pump to the filter and then go from there.

get the FSM wiring manual because that'll greatly help you.

it sounds daunting but in light of going aftermarket for ITBs on a 16v, it's the less painful route in my opinion. because when it's all wired up using pre-existing wiring, harness and ecu; you know it'll fire up and run right away. no trip to the dyno or use of fuel/ignition maps from other cars possibly using different sensors and who knows what other variables.

any automotive wiring seems insurmountable. but again, working with pre-existing wiring then you're already half way up the mountain.

bt20v
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Re: 20v questions

Post by bt20v »

hey slo im in the same process...I have a runing and driving sr5 and working on getting my parts for the BT20v swap. All I can say is read read read and read some more. As far as I know the sr5 and gts 5 speeds are the same its the bellhousing and flywheel that are different as the bt20v is an 8 bolt flywheel (like GTS). and the belhousing has the clutch slave on the opposite side. Are you in DFW hit me up if ya got questions.
Being a toyotaphile is hard work

1987 GTS Coupe
1985 Toyota 4 Runner Locked and Lifted
1995 4 Runner(sold)
1991 Hilux(never should have sold)
1985 Hilux(wrecked)
1985 GTS Hatch(sold)
1985 SR5 Coupe(sold)
1985 SR5 Coupe(sold)

nomuken
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Re: 20v questions

Post by nomuken »

Just posted this to guy on another forum a few days ago, so I thought I would contribute:

There are a few different ways to solve the problems when trying to fit the 20V in the hachi.

Distributor: The AE111 dizzy won't clear your firewall. 3 solutions: a) you hit your firewall with a big hammer or cut it untill it fits. b) you buy a distributor relocation Kit. Mine was from SPTec. c) you will go wasted spark like the 4AGZE engine. When choosing a) you have to pay attention that you don't destroy your heater on the other side of the firewall

Waterlines+Pump: AE111 is a FWD engine, so you'll have to modify the waterlines and combine the back half of a 20V waterpump with the front half of a 16V waterpump. Waterline Kits can be got from T3, RS Chita,... mine was from SSWorks

Electronics: I had a blacktop ECU for my blacktop engine. worked just fine. Got a complete wiring loom from Dr Tweak (aka Phoenix tuning) it really was plug and play for my car

Ignition: Your coil and ignitor from the 16V won't work, so you'll need a 20V coil and ignitor.

Airbox: if you are good at welding you can modify the blacktop box. But it's really big. So you can run open trumpets with cone filter or a big pipercross open filter or a pipercross/TWM/... Airbox

Header: The two outer mounting holes of the 16V header need to be modified for the 20V block

Hmm, I think that's all I can think of for now. My Blacktop had (with everything OEM) 152 hp on the dyno and revved up to 8300rpm with the OEM automatic ECU. It's a cool engine, but it's not cheap to make it fit properly fit in an AE86. If you can mount most of it yourself you'll roughly have:
Distributor Kit 500
Waterline Kit 600
Wiring Loom 500
Engine+Ecu 1300
Ignition coil 100
and some other things
You won't make it < 3000 (mine was about 4500) and for that money you can buy lots of nice parts for a 16V. Don't get me wrong, ITB's are great, high revving blacktops are great,... but not cheap.

I broke 2 BT's in about 2000km, always had rod bearing failure wich also damaged the crank, so I chose to go back to 16V

Enough text for today, if you have other questions, feel free to ask

Munki
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Re: 20v questions

Post by Munki »

this is how much i paid for mine \/

motor set - 1200
waterline kit - 400
oil, gear oil, coolant - 50
had to buy lots of bolts from dealer - 60

total = $1710

If you just buy a complete motor swap you'll get the wiring, coil, igniter and everything else you need. Im also using my stock distributor setup. Wiring wasnt hard either... very simple if you know how to read wiring diagrams.

To the OP,
Bring your car to my shop with a complete blacktop swap and waterline kit and ill put it in for you for about 500. So, for about 2200 you can have a BT ae86. lol

bt20v
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Re: 20v questions

Post by bt20v »

u all are gonna hate me i got an sr5 running and driving.....for 1500 it came with a blacktop harness computer coil everything....just look around deals are out there...
Being a toyotaphile is hard work

1987 GTS Coupe
1985 Toyota 4 Runner Locked and Lifted
1995 4 Runner(sold)
1991 Hilux(never should have sold)
1985 Hilux(wrecked)
1985 GTS Hatch(sold)
1985 SR5 Coupe(sold)
1985 SR5 Coupe(sold)

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Sam-Q
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Re: 20v questions

Post by Sam-Q »

The only way the blacktops are weaker is thinner rods, which will not fail with the factory rev limit. This is easily fixed with some aftermarket rods which is pretty cheap these days. My next engine in the build will have a 9200rpm rev limit.

I personally suggest an aftermarket ecu and twin/quad coils. You see the standard ecu for a 20v is highly restrictive with very lazy ignition timing. Expect an increase in power everywhere with a good tune and a very significant increase in the mid range. So I think it's a total waste of money buying a dizzy relocation kit. I wrote a bit about it here: http://s-86.com/s-ecu.html . Also if you add up the price of the stock ecu + loom + dizzy kit + loom mods your probably not far from what it would cost to get something proper.

I also think external water lines and particularly any firewall mods is not acceptable, but that's just my personal opinion. If you want more info on the swap I have two artciles that should interest you:

http://s-86.com/s-20vrwd.html

http://s-86.com/s-newcoolingguide.html


disclaimer: I sell cooling parts but that's not why I am posting here or trying to get revenue or why I have the opinions that I do.
-- My website --

http://s-86.com
Articles, Parts for sale, services, projects, pics...

dr.occa
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Re: 20v questions

Post by dr.occa »

no worries no worries. besides, your coolant products are splendid Sam.

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Sam-Q
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Re: 20v questions

Post by Sam-Q »

yes thanks, I just posted my disclaimer because I want people to know I am not here for free advertising.
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http://s-86.com
Articles, Parts for sale, services, projects, pics...

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