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Discussion Starter · #1 ·
Just a bit of brainstorming here...I was wondering what people thought of running a standard 16V large port on Megasquirt with ITBs from say a silvertop 20V?

I don't think I have seen anyone do this. No doubt because it would be cheaper to do a complete swap but let's say you have a newly rebuilt 16V and have the itch to do something different.

What kind of bhp gains would one guess?
 

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I'm thinking response would be the biggest difference. Go for it.
 

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why not? It is just a simple ECU. I am running a TEC3 which is almost the same thing. I have a higher resolution for fuel and timing tables and more input outputs.
There are a bunch using the MS on the 20v. So how much more power on the 16v?
Well you need to consider that the power on the 20v is made from much higher compression and better head design. It is not really the ITBs. As we posted in another thread about roller throttles and single vs multi TBs, it all depends on the RPM that you want to make power at.
ITBs will make the engine respond better at the throttle. Mor power? Probably not until you get way high in the RPM range. Definately better throttle responce because you will have a smaller throttle opening at low throttle angles. This make for better responce. You also will ahve better mixture control using ITBs as the fuel will atomize better thus making more power with the same amount of fuel.
 

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Discussion Starter · #5 ·
The 20V uses a significantly more aggressive cam lift also, no?

More power? Probably not until you get way high in the RPM range.
How high are we talking in the rpm range? Above 4300rpm? Above 6000rpm?

Definately better throttle responce because you will have a smaller throttle opening at low throttle angles. This make for better responce.
I'm all about the response. My lower end was dynamically balanced and uses early internals in a 7 rib block. That with the fidanza flywheel makes it rev well. I enjoy good response more than absolute power.

My thoughts are that the megasquirt will be making the majority of the power. The standard ECU is nearly 20 years old and tuned for 87 octane. Even with some "safe" tuning for 91 octane I'd think the increase in useable power would be 10rwhp throughout the range. Am I wrong?
 

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redvalkyrie said:
My thoughts are that the megasquirt will be making the majority of the power. The standard ECU is nearly 20 years old and tuned for 87 octane. Even with some "safe" tuning for 91 octane I'd think the increase in useable power would be 10rwhp throughout the range. Am I wrong?
No, I think you are right..

When I ran my car NA in between the twinscrew and turbo setups (even with low 9ish:1 c/r)... it pulled way harder than any mr2 NA ive driven.

The motor was controlled by the Hydra Nemesis 2.1 EMS (Full standalone, no AFM). EMS controlled the TVIS, and this was just a street tune.

This was with KK294 cams, TED built stock motor, light headwork, Header, exhaust, intake, 8200 rpm redline.

It pulled great from 5500-8000 rpm... considering it was a relatively low c/r, 1.6L NA.
 

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there is one in vancouver, wa that's being built in an ae86 right now for 16V, itb, and MS. I too will be doing the same. I have the T3 adapter, the ITB's, and the megasquirt. Just need to figure out how edis4 works with MS1 ver3.0 then wire it up.
 

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running a MS2 with the 20v (with ITB still on...unless I win bill's intake mani on ebay :) )

using MAP w/TPS blending and it works fine, though I'm still working on dampning the MAP signal so its a bit more stable. And Bill, it took me like a month of fiddling around to realize that you NEED to do MAP/TPS blending to make the accel enrichments work right, and right after I figure it out you post it in the other thread about where to get exhaust manifolds!!! At least now I know I'm on the right track!

Mike
 

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I just spent like 4 hours trying to figure out what the heck Alpha-N is

Its just speed density or fuel based on Throttle position sensor

Or in other words for a certain position of the throttle plate so much fuel is added

Does that sound right?

The Megasquirt is starting to become a pain in the A$$ and I got 25 years in electronics

It?s not for the faint of heat that?s for sure

Davegt27
 

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mann said:
running a MS2 with the 20v (with ITB still on...unless I win bill's intake mani on ebay :) )

using MAP w/TPS blending and it works fine, though I'm still working on dampning the MAP signal so its a bit more stable. And Bill, it took me like a month of fiddling around to realize that you NEED to do MAP/TPS blending to make the accel enrichments work right, and right after I figure it out you post it in the other thread about where to get exhaust manifolds!!! At least now I know I'm on the right track!

Mike

You wanna share your maps? :)
 

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Me myself would not waste the money on MS
I would go with a MAP setup and send the ECU out to Techno Square to put a new eProm in

Max
 

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megasquirt is EITHER map based or alpha-n based - you choose.

my 4agze seems to run pretty damn good - w/o dyno tuning in my aw11 i've been able to keep up with a turbo mk2 at high speeds (not gonna say how high, but it wasn't the speed limit.....). my setup is simple: ae101 gze, mr2 e51, megasquirt & edis4. The car seems to be a bit faster than another board members 88 celica alltrac as well (stock boost).

for anyone who wants, i have some turbo maps, a 20V map or two, and my modified maps that my gze are running on.... just get ahold of me via email (it may take me a while since my maps are actually on my laptop which is hiding somewhere else in the house)
 

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I'd share my maps but its in too shoddy of a tune for me to share them quite yet (though I'll put them up if people really want them). Its driveable but its nowhere near its potential. My main issue is trying to time this thing, I've heard anywhere from 12 to 30 degrees at full boost...(9psi) I ran it at 25 or so with no noticed ill effects, however out of paranoia I dropped it down to 18 or so, but power has suffered. When I ask people what it should be all I can get is "go to a dyno", well, if there was one close by I would, but I don't trust the car to 50 miles just yet...

As for alpha-n that's computing fueling using coolant temp and rpm I thought, and is there for something stupid like lawnmower engines.

Does anyone actually have a turbo 4age timing map on stock hi comp pistons? (not 4agze or forged...) And AFR map? I know I need ~11.5:1 or so for full boost, but what about low boost...i.e. 3 psi cruising on the highway...timing too, for long duration low boost what timing should it have to avoid meltdown...nobody seems to have that answer either.

Mike
 

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Yeah no one wants to stick there neck out on someone else?s car

That guy Brent probably has had the 4AGTE the longest (on MS) I would ask him

I know hardly anything about boost but on a NA car the more compression you have the less total timing

I know weak answer but boost is like adding Compression so I would not go to crazy with advance

Of course run the best gas you can with some octane booster (because of the story I just herd on the news about gas Companies putting in low octane for mid grade)

At the drag strip I used to do what they call a plug cut
Basically what that is as I go across the finish I don?t let the rpm fall off I cut the ignition off and coast off the track after the turn off I pull onto the grass or what ever and get out and pull the spark plugs and check them

ha ha old school stuff

davegt27
 

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You know guys... you could post all of your mods, then post a copy of your maps. Then the xperts could review them and maybe make some suggestions.
I know sometimes it is embarasing since a lot of us jump into things like this kind of tuning with little or no knowlege of what we are actually doing. But this is the way that you learn. And maybe our members can help at m,aking your car much more enjoyable.
 

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mine runs, but REALLY rich (ie, 15mpg with the s/c on). i'm keeping it this way until i get a wideband o2 to really see what's going on. however, it's been enough to have my mr2 make several 100+ mile trips along with auto-xing
 

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Where'd you post em? We should have a little sticky dealie in the aftermarket ecu forum for maps and maps only.
 
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