The dark side

[jondee86]

totta Crolla Wrote:...but will it be possiblefor me to modify my loom to suit the 20v engine ?

It would be possible (anything is possible), but may not be the neatest
way of wiring the engine. You most likely will want to run sequential
injection and wasted spark, which means adding extra wires. And every
plug will be different, so make sure you get the clips for the injectors and
sensors with your new engine. You will need to change to TPS wiring and
add the extra wires for the ISCV and oil solenoid.

You may find it easier to locate some AE86 ECU plugs, and make up a
new loom with new wires. When you remove the AE86 engine loom, you
only need to extract (or duplicate) the reverse switch and wiper/washer
wires. Modifying the AE86 engine loom would mean completely opening
it up, identifying every wire, and changing/lengthening/shortening each
wire, plus adding some new.

Best to make yourself a diagram before you cut anything

Cheers... jondee86

[totta Crolla]

A mammoth task and that is without all the standard 20v install
issues.

I don't want to start a 16v vs 20v v turbo vs supercharger argument but
has anyone got any hard evidence (video) that the 20v swap actually makes the '86 faster by any measurable amount ?

Is it worth it ?
A question I might have asked before, tbh I can't remember !

This video of Zdoman suggests the swap is not worth the effort:

http://www.youtube.com/watch?v=hKaQSK0MLSE

Even taking into account the taller first gear of the 20v

[Ivan141]

Compared to stock 4age I'd say it is definitively an improvement. Not much point to a swap if you already have a decently tuned 16v though..

[Bean]

This is the reason why I built up my 16V instead of going 20V, after I didn't manage to get a Beams.

As jondee said it's possible but a considerable task. Good preparation will take you more than half the way. The 20V swap should be pretty straight forward from what I've seen (just two issues to solve, water and ignition - the later is not necessarily one considering your situation)

[totta Crolla]

What a great read that ^ was

It has completely changed my view and is convincing enough for me.
The cams he used were similar to blacktop ones and produced similar
power, that suggests that the smallport head flows enough air to support
160 hp and the head is not a limiting factor at these outputs.
Please correct me if I'm wrong.

[Project D]

the smallport head flow enough tu support almost 260hp on a strocked 4AG, so 160hp is not a problem

[Bean]

Project D Wrote:the smallport head flow enough tu support almost 260hp on a strocked 4AG, so 160hp is not a problem

260 only on very ported head. General rule of thumb is that un- or only slightly ported heads the smallport is better up to about 200@fly, above that you're better off with the bigport.

[Project D]

Ported head yes, but still way smaller intake than an big port head !
So it's not about flow (rule of thumb: bigger is the pipe, bigger is the quantity of air that can go through, aka flow)
but more about velocity and filling

When I see the amount of work on the old Tec Arts 4AG (bigport) and their new 7AG (smallport), there is far LESS work on the 7AG for the intake !!!
More volume (1.8L VS 1.6L) smaller port, same power (230hp)


PS: just in case, a 20v intake port is smaller than the 16v smallport.

[[Walaki]D`Lair]

totta Crolla Wrote:A mammoth task and that is without all the standard 20v install
issues.

I don't want to start a 16v vs 20v v turbo vs supercharger argument but
has anyone got any hard evidence (video) that the 20v swap actually makes the '86 faster by any measurable amount ?

Is it worth it ?
A question I might have asked before, tbh I can't remember !

This video of Zdoman suggests the swap is not worth the effort:

http://www.youtube.com/watch?v=hKaQSK0MLSE

Even taking into account the taller first gear of the 20v

In this video there was a bone stock silvertop in a HEAVY rallycar, with long 1st gear, vs. a lightly ported smallport in a stripped out rusted car...so its not really a fair compare

I run a blacktop in my AE86 and if you want to have ALMOST the same power as a mildly tuned 16V, with bottom end power and small consumption, its a no-brainer. But the silvertop is a pile of crap