Hotter cams and stock ECU

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austin86
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Hotter cams and stock ECU

Post by austin86 » Wed Jul 15, 2020 11:20 am

So I thought Id ask this question here, I'm working on a 88 for escort EXP with an HO motor. The HO escort motor uses the same ECU, vam and injector setup as a XR4TI, the on;y difference is that the injectors are lower PSI, the VAM is smaller and the ECU has a milder tune. Other parts like sensors are moistly the same with little different like the contenders and what not. Infact you can drop in the XR4TI ECU, VAM and injectors in a escort with a HO motor without having to doing anything but swap the parts out.
Witch is why I thought Id asked this here. I have a HOT cam for the car, rather hot, .472 deg of lift at the valve, stock ins mid .200 something if I recall. My question is can the stock ECU and fuel system run with a hot cam. Or would I need to get the ECU tuned or something else?

Thanks.
Last edited by austin86 on Sun Jul 19, 2020 8:33 pm, edited 1 time in total.

my8950
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Re: Hotter cams and stock ECU

Post by my8950 » Wed Jul 15, 2020 4:07 pm

What is your source for this information?
I had and 88.5 Escort GT way back in the day, so I don't recall the details of these parts.
But, I also find it hard to believe Ford would use a big injector in the Escort/EXP.
I don't see how they could run the same EEC and calibration when the car's are quite a bit different.

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andyofcolumbusmerkur
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Re: Hotter cams and stock ECU

Post by andyofcolumbusmerkur » Wed Jul 15, 2020 6:01 pm

I was told the xr or svo ecu (sorry ECC-IV module) is 8 bit while the intercooled thunderbird turbocoupe is faster and 16bit. The Stinger performance website says that though the rated horsepower may be lower than the svo it could make more power and be a better choice. I believe it. My car seems to have all kinds of mods done to it by previous owners (Sun Valley Performance) like a cam and ported intake. It will run like a clock all week until I start to get into boost a lot. Then it gets all confused and runs like crap. If I unhook the negative battery terminal after driving it and hook it back up the next day it runs great again. Blowing off metered air also doesn't help I guess. Two of the coolant temp sensors are unhooked, along with the knock sensor. The ecm is not real smart and works fine in stock form. It won't freak out with a few mods, but has it's limits. This is why people mess with megasquirt or pimp or whatever. Will the ford ecm run a different ford motor? Sure. Will the ecm run bigger injectors or bigger air meter? Sure. Can you trick it and have different base timing? Sure. Can you port stuff out or run bigger exhaust? Sure. Can you run a ford performance cam or other mild street strip cam? Sure. Can you run a super wild custom spec cam? Maybe. Driveability will suffer I'm sure. Sounds cool though post up some pics when it's all together. :cheers
"Let me go get the keys to your brand new Hyundai!" Nooooooooooooooooooooooooooo!

austin86
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Re: Hotter cams and stock ECU

Post by austin86 » Sun Jul 19, 2020 7:32 am

my8950 wrote:
Wed Jul 15, 2020 4:07 pm
What is your source for this information?
I had and 88.5 Escort GT way back in the day, so I don't recall the details of these parts.
But, I also find it hard to believe Ford would use a big injector in the Escort/EXP.
I don't see how they could run the same EEC and calibration when the car's are quite a bit different.
Its a very common swap, you can ether just drop in the ECU (early tbird ECUs work too) but if you want to use the bigger injectors from a xr3ti or the vam you have to use both with the ECU.
Over on FEOA it the swap is spoken of quite often.
You can find a lot about it from the link below.
https://www.feoa.net/threads/1st-gen-es ... ance.7162/
andyofcolumbusmerkur wrote:
Wed Jul 15, 2020 6:01 pm
I was told the xr or svo ecu (sorry ECC-IV module) is 8 bit while the intercooled thunderbird turbocoupe is faster and 16bit. The Stinger performance website says that though the rated horsepower may be lower than the svo it could make more power and be a better choice. I believe it. My car seems to have all kinds of mods done to it by previous owners (Sun Valley Performance) like a cam and ported intake. It will run like a clock all week until I start to get into boost a lot. Then it gets all confused and runs like crap. If I unhook the negative battery terminal after driving it and hook it back up the next day it runs great again. Blowing off metered air also doesn't help I guess. Two of the coolant temp sensors are unhooked, along with the knock sensor. The ecm is not real smart and works fine in stock form. It won't freak out with a few mods, but has it's limits. This is why people mess with megasquirt or pimp or whatever. Will the ford ecm run a different ford motor? Sure. Will the ecm run bigger injectors or bigger air meter? Sure. Can you trick it and have different base timing? Sure. Can you port stuff out or run bigger exhaust? Sure. Can you run a ford performance cam or other mild street strip cam? Sure. Can you run a super wild custom spec cam? Maybe. Driveability will suffer I'm sure. Sounds cool though post up some pics when it's all together. :cheers
thanks

After I asked around on other sites I found that a big cam can be tuned in by adjusting the springs in the VAM.

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DPDISXR4Ti
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Re: Hotter cams and stock ECU

Post by DPDISXR4Ti » Sun Jul 19, 2020 2:24 pm

austin86 wrote:
Wed Jul 15, 2020 11:20 am
The HO escort motor uses the same ECU, cam and injector setup as a XR4TI, the on;y difference is that the injectors are lower PSI, the VAM is smaller and the ECU has a milder tune.
Your comment above is easy to misinterpret, so let me try to clarify... The engine in the HO Escort is NOT a Lima 2.3 and the two share nothing in common other than both being 4-cyl Ford engines from roughly the same era. The fuel injectors are different volume outputs. Fuel pressure is mostly irrelevant. Also, I suspect the Escort injectors are high impedance, not low like the 2.3T injectors.

I'll stop there for now. Need to get outside...
Brad

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Re: Hotter cams and stock ECU

Post by my8950 » Sun Jul 19, 2020 3:52 pm

DPDISXR4Ti wrote:
Sun Jul 19, 2020 2:24 pm
austin86 wrote:
Wed Jul 15, 2020 11:20 am
The HO escort motor uses the same ECU, cam and injector setup as a XR4TI, the on;y difference is that the injectors are lower PSI, the VAM is smaller and the ECU has a milder tune.
Your comment above is easy to misinterpret, so let me try to clarify... The engine in the HO Escort is NOT a Lima 2.3 and the two share nothing in common other than both being 4-cyl Ford engines from roughly the same era. The fuel injectors are different volume outputs. Fuel pressure is mostly irrelevant. Also, I suspect the Escort injectors are high impedance, not low like the 2.3T injectors.

I'll stop there for now. Need to get outside...
Beside what I mentioned above, and what is stated here, did you read that site?
Nevermind the info on there is from 2004, to me it sounds like a lot of "you should be able to" or "that should work"....
No real experience, and almost seems like no real knowledge of the car they're talking about.

austin86
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Re: Hotter cams and stock ECU

Post by austin86 » Sun Jul 19, 2020 8:37 pm

Umm its been done by over a dozen user on feoa. If you read past the OP one would see that.
There are also posts from other littered all over the site about the swap. Aside from the VAM, ecu and injectors all other eliteonics parts are the same. Don’t believe me? Just cross reference the PNs on any reputable parts site.

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Re: Hotter cams and stock ECU

Post by MarkM » Sun Jul 19, 2020 10:33 pm

What I'm really reading here is that the EXP with the HO engine uses the same type of engine management system as the 2.3 Turbo (VAM for air intake measurement, fuel injected, EEC-IV ECU) and has a wiring harness that's either plug and play or close enough that a few pin swaps will make it so. Combined with some sensors that are common across both platforms and you can swap the Merkur (or other Ford 2.3 Turbo) ECU, VAM and injectors into the Escort if you want to raise the limits on your air metering and fueling capabilities.

Sounds reasonable to me so far. I don't know that this is true, but it at least sounds plausible. Out of the box, I doubt it will be optimal due to the differences in displacement and fuel/timing maps of naturally aspirated vs. boosted engines. Of course, the EEC-IV ECUs can be tuned, but with the additional time/effort/$$ that involves, you need to look at the other options and see if they make more sense.
Mark

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Re: Hotter cams and stock ECU

Post by DPDISXR4Ti » Mon Jul 20, 2020 9:59 am

MarkM wrote:
Sun Jul 19, 2020 10:33 pm
What I'm really reading here is that the EXP with the HO engine uses the same type of engine management system as the 2.3 Turbo (VAM for air intake measurement, fuel injected, EEC-IV ECU) and has a wiring harness that's either plug and play or close enough that a few pin swaps will make it so. Combined with some sensors that are common across both platforms and you can swap the Merkur (or other Ford 2.3 Turbo) ECU, VAM and injectors into the Escort if you want to raise the limits on your air metering and fueling capabilities.

Sounds reasonable to me so far. I don't know that this is true, but it at least sounds plausible. Out of the box, I doubt it will be optimal due to the differences in displacement and fuel/timing maps of naturally aspirated vs. boosted engines. Of course, the EEC-IV ECUs can be tuned, but with the additional time/effort/$$ that involves, you need to look at the other options and see if they make more sense.
What Mark said. :withstupid

It's not unlike the guy who swapped in a MN-12 T-bird computer, injectors and MAF into a Scorpio (although that made a little more sense since both are N/A). But every engine is going to have different fueling/timing requirements. It might work okay - might even be "better" in some ways - but certainly won't be optimal across the board.
Brad

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