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renob123

So...Am I the first to have a Frankenmotor in his Brat?

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Fair enough :)

 

I truthfully had never thought of that before, so that's why I mentioned it, when I saw what you wrote. I thought that it was a great idea to be able to use the bigger block for more power, but keep all the simple and reliable stuff. It's the best combo, so thanks for pointing out yet another reason to do this motor :) Even if you don't go all "crazy" with the cams, I still think that this is a good way to go. Best of both worlds.

 

I was kicking this idea around in my head for a while. When my 2.2 started smoking more than I liked, I decided to see if I could do it. I was never really that impressed with the power of the 2.2. It was neat, and Brat suspension/brakes were overwhelmed by the power, but I was still underwhelmed. Now I'm trying to come up with ideas for suspension/brakes/transmission, since all of those things need to be redone now. I actually thought about a sequential-wannabe transmission similar to your 4EAT setup.

 

If you went with a similar motor, I think you'd shoot yourself in the foot by not installing the torque cams too. From what I've read, they're an improvement over stock all the way until the heads can't flow anymore anyway. How much time do you really spend above 5500 RPM or so?

 

Jacob

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I was kicking this idea around in my head for a while. When my 2.2 started smoking more than I liked, I decided to see if I could do it. I was never really that impressed with the power of the 2.2. It was neat, and Brat suspension/brakes were overwhelmed by the power, but I was still underwhelmed. Now I'm trying to come up with ideas for suspension/brakes/transmission, since all of those things need to be redone now. I actually thought about a sequential-wannabe transmission similar to your 4EAT setup.

 

If you went with a similar motor, I think you'd shoot yourself in the foot by not installing the torque cams too. From what I've read, they're an improvement over stock all the way until the heads can't flow anymore anyway. How much time do you really spend above 5500 RPM or so?

 

Jacob

 

That's a good point. I was more speaking hypothetically. If/when I do this to my car I will get the cams, go big or go home, right? :lol:

 

After spending some time working with an actually EJ harness that is going into a swap, I am kinda getting ansi to want to do this to my car. The wiring is more daunting when you don't really understand what's going on, but once you get the jist of it, it's not THAT hard, at least compared to my paddle shifters :lol: But money will keep that from happening any time real soon :-\

 

I am curious what the idle is really like though. Is it really that bad, or just barely noticeable? Can you describe what's it's like? Is it like knocking, and running rough, or just kinda slightly off when it idles?

 

My car is my DD, so as long is it's not totally unbarable I don't see any problem with it, the power benefits will out way the idle issues :grin:

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That's a good point. I was more speaking hypothetically. If/when I do this to my car I will get the cams, go big or go home, right? :lol:

 

After spending some time working with an actually EJ harness that is going into a swap, I am kinda getting ansi to want to do this to my car. The wiring is more daunting when you don't really understand what's going on, but once you get the jist of it, it's not THAT hard, at least compared to my paddle shifters :lol: But money will keep that from happening any time real soon :-\

 

I am curious what the idle is really like though. Is it really that bad, or just barely noticeable? Can you describe what's it's like? Is it like knocking, and running rough, or just kinda slightly off when it idles?

 

My car is my DD, so as long is it's not totally unbarable I don't see any problem with it, the power benefits will out way the idle issues :grin:

 

Hooking up the wires to the engine is pretty easy. I can only imagine how hard it is to pare it down to what you need, though.

 

I'll try to describe the idle, but I'm not sure if anyone would understand. Maybe I'll post a video if I get a chance. Imagine sitting in a parking lot with your car on and in neutral. You keep your foot on the gas with enough pressure to keep it at 1000 RPM. You let off the gas, and the RPMs get to 500 before you put your foot back on with the same amount of pressure. The RPMs go back up to 1000, then you let off again. The whole 1000 RPM-to-500 RPM-to-1000 RPM cycle takes about 1.5 seconds or so, if I had to guess. It's weird, because it acts like a ghost is pushing the gas gently and keeping very good time doing it.

 

I probably spend less than 1% of my time driving in the <1000 RPM range, so I don't see it affecting actual driving. It doesn't feel very rough at all. It's just a ghost that I'd get rid of if I knew how to. Actually, I guess it's technically a poltergeist, since it's interacting with objects...

 

Jacob

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I wonder if a high comp 2.2 would be powerful enough to propel my RX in a way that would win championships.

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That is freaking wierd. Maybe one of the electrical/electronic guru's will have some insight cough GD cough. Might be able to find something out on nasioc though also since technically your brat isn't all that old gen anymore. :rolleyes:

 

Mike

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Which PCM are you using? Are you using 2.2l injectors or 2.5l injectors? That might be part of the idle hunt, idle is usually open loop, and the base maps for idle fueling may be off enought to cause the hunt. Using 2.5 injectors may change that, I think they're a higher flow rate.

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I wonder if a high comp 2.2 would be powerful enough to propel my RX in a way that would win championships.

 

I'd imagine in your sport, it's about 90% driver. I encourage you to think a lot about what benefits that level of work on a 2.2 would give you over a frankenmotor.

 

Jacob

Edited by renob123

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I'd imagine in your sport, it's about 90% driver. I encourage you to think a lot about what benefits that level of work on a 2.2 would give you over a frankenmotor.

 

Jacob

 

Autocross is about the driver but often when you reach the "modified" classes you need lots of power to be competitive.

The 2.2 will be reliable and have a little more power/torque than the 1.8 turbo I blew up. my concern is the bottom end on mine has lots and lots of miles on it.

I may just run it till I can afford to build a stronger engine but I was thinking "make the leap now while it's down anyway"

From what I've been reading the Frankinmotor is more like a WRX on power with all the power and torque available all the time.

 

 

I think I should break away from the frankin motor thread at this point and start a new one.

Edited by vagen

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I think I should break away from the frankin motor thread at this point and start a new one.

 

I'll be monitoring your new thread as well to maybe pick up some tips or advice for my build.

 

Which PCM are you using? Are you using 2.2l injectors or 2.5l injectors? That might be part of the idle hunt, idle is usually open loop, and the base maps for idle fueling may be off enought to cause the hunt. Using 2.5 injectors may change that, I think they're a higher flow rate.

 

It's a '92-ish Legacy computer with 2.2 injectors. I'm going to hook up an A/F meter soon to see where I'm sitting. If I'm running lean, I figure I can change injectors or up the fuel pressure. Which 2.5 injectors are you talking about that fit?

 

That is freaking wierd. Maybe one of the electrical/electronic guru's will have some insight cough GD cough. Might be able to find something out on nasioc though also since technically your brat isn't all that old gen anymore. :rolleyes:

 

Mike

 

Ehh, it's not completely old gen anymore, but it's better off with me than rotting in that field I got it from. Plus USMB is for all Subarus. I've been searching on NABISCO a lot, but it's honestly not that big of a problem. I just posted the video for eulogious. If someone happens to know how to fix it, that's cool, but I'm really more interested in deciding on the right transmission. Unless it really is a ghost, in which case I'd like to get rid of it soon:)

 

Jacob

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Here, try this:

 

 

Jacob

 

That's nucking futz man. This is a little off base, but whateva... This totally reminds me of what my parents honda lawn mower did right before we got the carb rebuilt. It would do that exact same thing. When they rebuilt the carb on the mower they said it was plugged up pretty good, but after a good cleaning and tuning it runs great now.

 

But this is very strange to see a car do that. It almost seems like it's starving itself for fuel, so then the computer kicks the idle up to keep it from dying then it's fine, and then it starts starving, the idle drops, and the cycle starts over again.

 

I wonder if swapping in 2.5 injectors as mentioned along with a 2.5 ecu would help? What are the differences in the injectors? It would make sense that they would be a little bigger to help with the increase in power going from 2.2 to 2.5, so then the ecu would also have to have different maps and what not to take advantage of the new injectors and to run properly.

 

But I really don't know what I am talking about :lol: I am just thinking out loud :D

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That's nucking futz man. This is a little off base, but whateva... This totally reminds me of what my parents honda lawn mower did right before we got the carb rebuilt. It would do that exact same thing. When they rebuilt the carb on the mower they said it was plugged up pretty good, but after a good cleaning and tuning it runs great now.

 

But this is very strange to see a car do that. It almost seems like it's starving itself for fuel, so then the computer kicks the idle up to keep it from dying then it's fine, and then it starts starving, the idle drops, and the cycle starts over again.

 

I wonder if swapping in 2.5 injectors as mentioned along with a 2.5 ecu would help? What are the differences in the injectors? It would make sense that they would be a little bigger to help with the increase in power going from 2.2 to 2.5, so then the ecu would also have to have different maps and what not to take advantage of the new injectors and to run properly.

 

But I really don't know what I am talking about :lol: I am just thinking out loud :D

 

Don't you think it's odd that the computer can't figure out how to keep the injectors open a little longer? If it's keeping them open the same length of time until it almost dies then kicks it up, then I wonder if a slight increase in line pressure would trick it.

 

I doubt a 2.5 ECU would plug into '92-ish 2.2 wiring. If it did, though, it would be sweet because I'd get a higher redline, I think.

 

Jacob

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Don't you think it's odd that the computer can't figure out how to keep the injectors open a little longer? If it's keeping them open the same length of time until it almost dies then kicks it up, then I wonder if a slight increase in line pressure would trick it.

 

I doubt a 2.5 ECU would plug into '92-ish 2.2 wiring. If it did, though, it would be sweet because I'd get a higher redline, I think.

 

Jacob

 

I guess that it goes back to the ODBI and ODBII simple/complex thing we were talking about earlier. I was just speculating...

 

You would think that the computer would realize to keep them open longer, but it could literally be limited by the math that the subaru engineers didn't put it :rolleyes: It just might be too much torque/power for the ej 2.2 ecu to handle.

 

Upping the fuel pressure seems like a good idea to me, but I know nothing about fuel systems really, so I am no expert and have no idea what it would effect. But if you start putting just a little bit more fuel to the system a little at a time and see what happens, I can't imagine what you could really destroy, but again, what do I know :lol: But I would give that a try and see what happens. That would be great if that was all it needed! :)

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I guess that it goes back to the ODBI and ODBII simple/complex thing we were talking about earlier. I was just speculating...

 

You would think that the computer would realize to keep them open longer, but it could literally be limited by the math that the subaru engineers didn't put it :rolleyes: It just might be too much torque/power for the ej 2.2 ecu to handle.

 

Upping the fuel pressure seems like a good idea to me, but I know nothing about fuel systems really, so I am no expert and have no idea what it would effect. But if you start putting just a little bit more fuel to the system a little at a time and see what happens, I can't imagine what you could really destroy, but again, what do I know :lol: But I would give that a try and see what happens. That would be great if that was all it needed! :)

 

I'll look into that, but like I said, I want to focus on transmission/brakes/suspension before I worry about what people think of my idle. Unless it's a g-g-g-g-ghost:eek:

 

I hope the video helped give you a good idea of what it is. It doesn't affect daily driving in the least. I've commuted for about 500 miles with it so far with lots of stop-and-go traffic, and it hasn't bothered me at all.

 

Jacob

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Yeah - I think it may have something to do with the 2.2's ECU not being totally able to handle the 2.5's fueling requirements from it's idle maps. That's the current hypothesis.

 

It throws no codes, and the IAC is working. Something about the change made an existing slight stumble at idle (which I had figured was the IAC/old injectors, etc) into a nasty loping idle.... the cams have more overlap and we are asking for more fuel of course..... could be a bunch of things all rolled into it.

 

The fact that the ECU isn't complaining even a little bit about this is frustrating to say the least. The whole point of a self-diagnostic computer is that you don't have to break out the O-Scope every time you need to look at the sensor data. I think it's finally time to build a select monitor adaptor cable and run the OBD-I realtime monitor software on a laptop. Might tell us something.

 

GD

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It's a '92-ish Legacy computer with 2.2 injectors. I'm going to hook up an A/F meter soon to see where I'm sitting. If I'm running lean, I figure I can change injectors or up the fuel pressure. Which 2.5 injectors are you talking about that fit?

 

Jacob

The injectors out of a late 90's DOHC 2.5 should fit right in, you may be able to swap the 2 rails and not have to mess with the injector seals. There may be a difference in the indexing tab on the connector, you just shave the tab off the injector side plug so that the motor harness plug clips down on to them. I could poke around my shed and see what's what.

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One of the things I have found to help get more traction up front is to setup the front end for about 1/8th inch of toe OUT. Furthermore if you can move the struts inward towards the engine bay any amount at all, and re-drill the mounts that seems to help too. A last ditch resort would be to do all of the above and add about an inch thick spacer under the engine crossmember to drop the crossmember help change the camber angles further. You want to try to get the front control arms to be flat when viewed from the front of the car.

I have made some ea 81s that would handle insanely well, considering I lived in a twisty canyon for most of my life ;)

 

 

I definetly need to meetup and check this thing out ! Sounds like my kind of animal. My turbo brat has more than met its match by the sounds of it :lol:

 

Matt in Rainier Or.

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One of the things I have found to help get more traction up front is to setup the front end for about 1/8th inch of toe OUT. Furthermore if you can move the struts inward towards the engine bay any amount at all, and re-drill the mounts that seems to help too. A last ditch resort would be to do all of the above and add about an inch thick spacer under the engine crossmember to drop the crossmember help change the camber angles further. You want to try to get the front control arms to be flat when viewed from the front of the car.

I have made some ea 81s that would handle insanely well, considering I lived in a twisty canyon for most of my life ;)

 

 

I definetly need to meetup and check this thing out ! Sounds like my kind of animal. My turbo brat has more than met its match by the sounds of it :lol:

 

Matt in Rainier Or.

 

I go through Rainier pretty often. I was hoping to take it through there next weekend, but the part of me that thinks things through is telling me to figure out the transmission/brakes/suspension first.

 

Right now I'm toying with the idea of some kind of air shocks for the rear. The RX springs (if that's what they were) I got for the front were pretty disappointing. I've bled the brakes about 20 times on each corner with minimal improvement. I think I'd be happy with the brakes if they worked properly. I have a plan for the transmission, but it'll be a pain.

 

Again, it looks just like any other EJ-swapped Brat until you look very closely.

 

Jacob

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Don't be so sure. When this thing is done, it'll probably redline at 60mph:banana:

 

Jacob

 

That would be a shift every 10 MPH - I don't think your arm and clutch foot can move that fast let alone have the syncro's mesh up :lol:

 

GD

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You need to do an AWD setup in your brat. I've got a phase 1 ej25 sitting at my house waiting for the same setup as yours. I'm going to be putting it in my AWD hatch next summer.

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I am getting tempted every time I see a new post in this thread... it would be so easy just pop an EJ25 block between my Phase 1 heads and voila Frankinmotor.

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