450 injectors

[steelzeus]

I have an an auto 1st gen and from what I understand it has 390cc injectors if I put the 450s from a manual on it will the pcm adjust to be adjust to use them or will i need something else?

 

[toofast82]

+1 above and you have a 1g so there is endless amounts of changes that can be made

 

[jrohner]

All three 91 turbo cars I've owned had EPROM ECU's, so I'd say you have a high chance of having one already.

 

[toofast82]

yes i had a 90,91,92 and they all had eprom. If you check the code on the computer if it has an "e" than its eprom. I would always recommend taking the cover off to be sure though. 4screws, very simple

 

[Bud92gsx]

yes i had a 90,91,92 and they all had eprom. If you check the code on the computer if it has an "e" than its eprom. I would always recommend taking the cover off to be sure though. 4screws, very simple

4 Screws is right, very easy...
Most of them did have eproms...
My GSX has an eprom..
On my talon it says 91 or 90, but no eprom, it's weird... I have a pic somewhere, but it's probly on my computer and that's down..

 

[steve]

All three 91 turbo cars I've owned had EPROM ECU's, so I'd say you have a high chance of having one already.

yes i had a 90,91,92 and they all had eprom.

Most of them did have eproms...
My GSX has an eprom..
On my talon it says 91 or 90, but no eprom, it's weird.

How many of these cars did you buy new?
I can assure you that most of them did not have EPROM's.

 

[DSM_Nick]

Mine is a early 92 Talon. I still have to check mine, I have no idea if it is an eprom or not. I am hoping on a good chance it is though

 

[Bud92gsx]

Steve would be the one to ask on this one...Yes I saw his post. I thought most of them did come with eprom, but I guess not...

 

[gsx7707]

turn up the boost to compensate

 

[dylnwit]

I'd personally spend my money on a logger first, do some logs so you know where your car is at and then move on from there. If your under 75% injector duty cycle at wot, might as well turn up the boost or strap on a 14b or even a 16g. Just my .02

 

[DSM_Nick]

I'd personally spend my money on a logger first, do some logs so you know where your car is at and then move on from there. If your under 75% injector duty cycle at wot, might as well turn up the boost or strap on a 14b or even a 16g. Just my .02

The fuel management will be the dsm link for me. And no idea on how to get or use a logger. But I already put on a 16g and I can't boost anymore boost. It just won't boost any higher, no matter which turbo I had on. Seems like the engine can't take more than like 9 psi in mine

 

[BulletShiftTSi]

If your car is the one in your avatar (which its supposed to be according to guidelines)
you have a later 1992
aka 1992.5 (april 1992 - 1994)
aka eagle talon 1Gb

If you still have the stock cams injectors fuel pressure regulator pump (no rewire) and no fuel tuning device like SAFC or DSM link then yea its going to be harder to get more boost out of it.

whats done to the car besides the 16g?

P.S. i have a 1992.5 talon with a evoIII 16g 272 cams SAFC-II etc, and here to help!
I'm running 20lbs

 

[DSM1G90]

I want to chime in on this topic a bit with a variation that I came across: When I got my Ply, (5sp manual) it has a JDM GalantRS 4G63T motor in it which came with the 16g and the 510cc (yellowtop) injectors.

When I got this thing, it was running horribly rich - the CAS was cranked all the way open to 'try' to compensate for the rich fuel delivery.

I knew right off that the ECU that was in the car only knows about 450cc (bluetop) setup - why the thing was running so rich. I took out the 510's and shove back in the stock 450's, retimed the vehicle, got my MPG back up and vehicle runs like a dream now - with more power than when I got it.

-DSM

 

[DSM_Nick]

If your car is the one in your avatar (which its supposed to be according to guidelines)
you have a later 1992
aka 1992.5 (april 1992 - 1994)
aka eagle talon 1Gb

If you still have the stock cams injectors fuel pressure regulator pump (no rewire) and no fuel tuning device like SAFC or DSM link then yea its going to be harder to get more boost out of it.

whats done to the car besides the 16g?

P.S. i have a 1992.5 talon with a evoIII 16g 272 cams SAFC-II etc, and here to help!
I'm running 20lbs

Ok, thanks. Yeah that is my car, and it might be April of 92. I just thought it was an early 92 even though it doesn't have the pop up headlights.
And yes I have stock everything besides a manual boost controller and an Evo III big 16g in to. Plus I already put in 450cc injectors. But they are not doing anything more than my 350cc injectors cause it is not tuned for it. I am getting dsm link pretty soon to tune everything.

Ok, thanks for the help. So how did you get up to 20 psi?

 

[DSM_Nick]

I want to chime in on this topic a bit with a variation that I came across: When I got my Ply, (5sp manual) it has a JDM GalantRS 4G63T motor in it which came with the 16g and the 510cc (yellowtop) injectors.

When I got this thing, it was running horribly rich - the CAS was cranked all the way open to 'try' to compensate for the rich fuel delivery.

I knew right off that the ECU that was in the car only knows about 450cc (bluetop) setup - why the thing was running so rich. I took out the 510's and shove back in the stock 450's, retimed the vehicle, got my MPG back up and vehicle runs like a dream now - with more power than when I got it.
-DSM

That's pretty cool about the engine in there. Good deal on that. But one correction is that the 510cc injectors shouldn't make it run any richer if the computer thinks it has 450cc's. Because your ECU determines the pulse width for the injector and how much it puts out. Just changing injectors doesn't do anything unless it is tuned

 

[steve]

But one correction is that the 510cc injectors shouldn't make it run any richer if the computer thinks it has 450cc's. Because your ECU determines the pulse width for the injector and how much it puts out. Just changing injectors doesn't do anything unless it is tuned

Your correct that the ECU determines the pulse width for the injector but the rest is incorrect.
The ECU is programmed with the size of the injectors. It gets a measurement of the mass of air each rev and figures out how much fuel is required for a 14.7:1 AFR. It's then looks to see if it needs to modify that AFR because it in open loop and gets the modifer from the fuel maps. Once all the adjustments are made it determines the pulse width for the injector from the size value. If you put different sized injectors in from what the ECU thinks you will get the wrong amount of fuel. So those 510cc injectors will spray more fuel that a set of 450cc injectors would in the same pulse width assuming the deadtime is the same.

Changing injectors requires tuning to get the actual AFR to match the ECU's target value.

 

[DSM1G90]

tuning to get the ECU's target AFR to match the actual.

.. where I was told if I kept the 510's in there, I'd had to go to a engine management source to compensate, and I didn't want to do that.

ALso, I bet that the Ox2 sensor was also having fits with the ECU to try to even get close to a close loop system with it running so rich as it was. Even the plugs before I did the injector swapout were pretty knarly looking from being all sooty looking .. and they were hotter plugs than needed - whoever had this car didn't know what they had under the hood after the JDM swapout.

Thus, I knew that getting things back in what the ECU knows would get system operation definitely in a close loop form.

I don't even use a K&N filter and a cut up, or totally eliminated aircan knowing that the snorkel out front actually cools the air coming in due to the highly increased airspeed going inside the can along blocking under the hood engine heat (and still have my EXH manifold shield on).

Guess one can say, "if it aint broke, don't mess with it." - but it's a "Road Rocket" for sure...

Doing injectors, belts, pulleys, NGK BPR6ES's, MT-90 tranny fluid, et.al. , that day was, in itself, a big one. I brought it home slightly huffing on one cylinder and when I took it out after all this PM stuff, it actually scared me on how much power was produced.

...just have a slight bit of turbo lag...but guess that's expected with an EVO-I, big 16G turbo..

thx-DSM

 

[DSM_Nick]

Oh ok, thanks for that. I did not know that at all. The correction helped me out a lot. So by putting in higher cc injectors they will actually put out more fuel without any tuning? Just wondering cause I have some 550cc evo injectors that I would like to put in. And one more question, what should a good air/fuel ratio be?

 

[toofast82]

in closed loop it should target 14.7:1 and at wot a good target afr will be between 10.5-11:1 on pump for a safe tune. stock is in the 9s so there is improvement to be made there

 

[DSM_Nick]

Ok, thanks. Yeah I was wondering about that. Definitely a good thing to know, I need to get my A/F gauge in so I can see what mine is at. Turned up my boost a little, so maybe it is at 10 or 11 now.