Dynoed Today

Jason

IMHO the air that your combo is moving at this time is not GREATLY hindered by the stock inj's, tb, or maf.

The lean ratio is showing that there could be a mechanical prob with one of those stock parts for sure but I don't think it is due to them not being able to support your motors airflow.

You say the tech tried 60lbs of f p and the ratio did not come down. That says there is a major hose up some where.

You said that 19's are good to 300 hp. First of all, most of those inj sizing programs are giving values that are crank hp so rwhp would be about 255 in this case.

I can say for sure that with stock inj's, tb, maf, and t4m0 pcm a cai will cause the af ratio to go lean by a good bit on a 94-95 t4m0 car. Raising the fp should drive it down and that is why I think you've got something like a weak inj, clogged fuel filter, or the like.

You're non still running the stock fuel pump .... are you???

After you find what is causing the lean prob I would not want to go for much more power without some larger inj's or at least be able to gain a better ratio by doing the afpr thing.

Later
Grady

you can ohm out injectors...it should be in your haynes or whatever...have done that test, same as a noid test....it proves they work but a clogged one is tough..you gotta pull the rail and watch the pattern...done that before...real voodoo with fuel spraying...DOH...
a bad injector will usually make em run like a mutt from my expierence..likes it running minus a cylinder...real rough....

i would check the codes than...maybe theres something there???

Fuel pump??? is it was that bad, or starving for fuel wouldn't it be falling on its face??? that doesn't appear to be happening???

I dont know if i agree with the 24s...the whole reason i didn't swap to 24s was to dyno and see if the 19s were maxxing out....no way...my graph proves they were in the sweet spot all the way...i was told the AFR would dictate if the 19s were being taxxed....i did it just to prove that point...I didnt see it...
you have Orange ones??

i only mention it as i been there with all the stock ECC stuff and it works....were in the same ballpark mods wise...only I have LTs???I had 4 different CAIs and have never seen MAF issues??? Densecharger, straights, 90 and 45 turns...So I dont know there???

Grady may have something on the FPR??? somethings wack there maybe...you should have seen a change with adjusting it....Shoulda bought a Kirban...
Just busting your stones there

mytight95 said:

Grady, i agree with you a lot....the pump is not stock unsure of the size, it was changed before i bought the car....But i will be changing injectors etc....the o2 sensors, are fairly new.....is there any way to test them, as i not getting any codes.....You think the CAI is making the car go lean.......? please explain... It has a nwe fuel filter along with a lot of other new stuff......Could be a clogged injector i guess........that wont make the whole a/f ratio go lean though would it....

:dunno: this one has me baffled..

jason

Click to expand...

Jason

I have no experience with the afpr's but I've seen it over and over many times from reading various dyno results threads. The afpr's can drive the af ratio down on the next pull after the afpr adjustment or while at the dyno. That is a given fact that, IMHO, we can't loose sight of.

Tom talked about the pcm's adaptive strategy hosing around with your af ratio. I've been doing a lot of work in that area lately and have learned a thing or two but without going into a bunch of stuff, even if you were to the full adjustment range of the pcm's adaptive strategy, the afpr adjustment should have made things fatter on the next pull.

In the past I've seen stuff about testing fuel pumps and inj's by seeing how much fuel the device can pump for 60 seconds and doing the math for lbs per hour. An old racers trick is to test a bunch of inj's using that method and then they pick out eight of them that flow the same amount of fuel for a balanced set on inj's.

As for the cai causing lean conditions I had a home made cai cause idle and part throttle probs when I was using stock tb, maf, and pcm. I can't say for certain that a cai would cause you grief at wot cause of this. When you go wot you go into a different mode of pcm operation and I never tested the cai for those conditions but let me think out loud for a second which might help to explain.

The t4m0 pcm is pretty bad about having too much spark and not enough fuel as they come from Ford. Ever wonder why so many peeps complain about the ping thing. Having said that, a cai can not help that prob at all under wot or dyno pulls. I've got dataloggs to prove that a cai will increase total airflow at max rpm. In your case, a weak supply of fuel would make for a more lean ratio.

Again, turn up the pressure and things should be good to go .... at least a while. There are just too many peeps that have proven that fact. You on the other hand did not benefit from that little trick.

I think you got a weak inj or fuel pump. Something is preventing you from getting a normal supply of fuel.

If I were you, I would find the prob before trying to squeeze out more power from your combo. That is too lean for max power and its not good for your motor.

As for inj size, IMHO, is is better to be safe than sorry and that is one of those things only you can deterine for yourself. I run 30's and I guess that speaks for that statement. However, just so I don't mislead anyone, I don't think I would tell others to run 30's on a MILD combo like mine if they did not have a tuner of chip to adjust for them.

btw .... the prob would not be 02's cause they don't work during that wot method of pcm operation we talked about.

Just had a thought. Wonder if your return line could clogged or the feed line also for that matter?

Your just gonna have to get in there and find out why your flow is no go

Later
Grady

mytight95 said:

Well RC, i meant to say lower it was late and i hadn't been home from my 2 hour drive very long.........i believe that you knew what i meant......
.

Click to expand...

You busted me!!!

However, I have seen a few people on some boards that still confuse the lean/rich thing, so I just phrased the question that way to make sure, even though I pretty sure you knew.

GL with the tuning!
RC

Running a EEC cylinder balance test may help find an injector issue.

The EEC can run a test on itself to see what cyclinders might not be working correctly. I have the procedure at home, but I'm at work. Maybe someone can link us up to the procedure.

Here you go...You can buy a code reader for 15.00 and it has this feature..I think this is the manual method...

http://www.mustangworks.com/articles/electronics/eec-iv_codes.html

Jason, I would check the MAF element first, same thing happened to me on the dynoonce and we cleaned it and it straightened out to a 13.5:1 ratio with the FP set at 38psi(vac off) and the 19# injectors. On the stock heads ported, typhoon intake, stock maf, 75mm tb, fcam, no chip I made 260rwhp and 292 rwtq.

I think either the MAF is acting up or you may be sucking unmetered air somewhere.