Guess I'm screwed. Too big for me?

cashsaudio · Post by **cashsaudio** » Fri Jun 30, 2006 11:18 am

Alright lets get this started.

Well you guys probably think im all nuts and stuff but I could not find any injectors thats between 110lb/hr to 125lb/hr. I don't even know if they exist. So I had to get the bosch 160lb/hr x 4 injectors for my 2.6L 4 cyl.
The good news that it idles pretty darn good but really rich. I dunno if my WB is working but is there such thing as 7.4:1 a/f ratio? If i rev, it jumps around really funny. I tried hooking up a NB sensor to get it to work but for some reason a used one and a brand new one don't work. I dunno y.

Here this what I'm trying to say. At idle if i mess with the injector char. I can avearge about 1.4-1.6 PWM. I know the car is running really rich and through "okay just tune the VE table down" Wrong it just cut the living crap outta it. I have the VE table looks like its all richened up (higher than the old 75lber's I had before). I took it for a spin and the best i got it was pretty stable that I can give it gas slowly but if i hit it to the floor fast it bogs then it kicks in. But I cant seem to get rid of this. I can give out my settings so far on here just gotta pull it off the labtop quick.

I have a turbocharger pretty big size I perfer not anouncing it but its way bigger than a T70 I can only get the thing boosted at like the max of 10psi. Whats wrong here? Too much fuel or too less?

I found out that when i ran outta gas my exhaust pressure was pretty abit higher than it was last time. Then i put gas in it and now I feel hardly any pressure through the exhaust. Is this a issue.

This what I have

MSII 3.0 firmware 2.35 megatune 2.25 I believe the code version is 4.00.

Please help me here I don't wanna waste another summer have problems like fuelinjectionpro.com been giving me.

Thanks

Jeff

fscott · Post by **fscott** » Fri Jun 30, 2006 4:48 pm

It sounds like your injectors are just way too big. And your turbo too, for that matter. Size ain't everything.

Those idle pulsewidths are getting very small. I'd suggest going to smaller injectors.

Fred

cng1 · Post by **cng1** » Sat Jul 01, 2006 7:33 am

You say the turbo is bigger than a T70, well there aren't many turbos bigger than a T70 and if you don't have any provenance for it then assume that it's a truck turbo, in which case it's designed for high boost, rather high flow and efficiency

cashsaudio · Post by **cashsaudio** » Sat Jul 01, 2006 1:37 pm

Okay I did assume they be too big but do you guys know where i can get about 115lb/hr anywhere? I know the turbo isn't too big and is not design for a diesal truck for my car i've seen bigger on the same exact motor as mine and done way over 800WHP. What I was thinking that either its getting too much fuel that its not spooling up the turbo or timing. My goal is 700WHP on the track and about 600 on the street.

Btw, Do you guys know what msd use for input-ouput. Because I only using msd 6a to trigger MSII so I use the green and violet input from the dist. and the tach output. Thanks

Jeff

jakobsladderz · Post by **jakobsladderz** » Sat Jul 01, 2006 8:20 pm

Staged injection may be the only solution if you are aiming for any sort of economy driving on the street. Even with accurate fuel timing from MSII you'll still have trouble getting accurate part throttle and idle performance with injectors that big. normally for that power output people are using 8 cyl engines on 550CC injectors, a much more idleable proposition. If you use the same number of injectors (i.e

but only use half unless you need them all, you might make life easier..

Just my 2c..
Duncan

cashsaudio · Post by **cashsaudio** » Sat Jul 01, 2006 10:06 pm

jakobsladderz wrote:Staged injection may be the only solution if you are aiming for any sort of economy driving on the street. Even with accurate fuel timing from MSII you'll still have trouble getting accurate part throttle and idle performance with injectors that big. normally for that power output people are using 8 cyl engines on 550CC injectors, a much more idleable proposition. If you use the same number of injectors (i.e but only use half unless you need them all, you might make life easier..

Just my 2c..
Duncan

You know that what I was planning on but on the other hand I didn't feel modding up my nice intake so 160 what my idea. I did read up about how injectors could be a problem idling. Well I had to try it out. So guess what my car idles really good after it warms up. I was out for a lil tonite and talked to another guy and i drove by him yesterday and asked him if my car was smoking at all when i was going underload. He said that he didn't see anything. What if I turn the fuel pressure reg. down about 1 bar will it help better? maybe drop the injectors to 135-140lb/hr? I have it set to 3 bar. I'm going to be messing with it more tomorrow.

This what my car does so far. If i lightly give gas and push down slow it may buck once but if I try to go faster to the floor and bucks quite a few time until i kick the boost in then its fine. Heres another thing that when I punch it to the floor, it cuts out for about one full second then kicks in. I see when i rev the car up with the laptop hooked up i see my PW jumps about 1.7 to 5 then back to about 2 or abit lower. Btw, I get no back fire at all which is a good thing lol.

My req fuel is 2.6-2.8. Okay one more question about this. When doing the ve table in tuning, does this mean that i have to have the graph really low or mid? Because when i used to have 75lb the graph looked more into the middle. I hope i explain this better. Because when i try to tune the graph lower it would kill the car but if i idle the car then rev, it cuts out and back fires, etc. I just want to be sure then i know I probably have to increase fuel.

Jeff

chicksdigwagons · Post by **chicksdigwagons** » Sat Jul 01, 2006 10:43 pm

I admire your persistance, and I do know what its like to end up with parts that just aren't going to work for your application. I think you've found those parts and you need to suck it up. 2.6 for a required fuel is very small and will definately cause idle problems and in general problems accurately metering fuel. You might have a little luck dropping the pressure, but 1bar is way too low to get any atomization from the fuel. You would be better off with perhaps some 90-100lb/hr injectors and bumping the pressure up. But in either case you better have a substantial fuel system to feed it.

My vote is for an 8 injector setup. I think you'd find much much better driveability since you seem to want to drive this creation on the street. For an all out drag car you might be able to make your 160lb injectors work fine, but for street driving you're asking too much IMO.

Good luck!

Uncle Bob · Post by **Uncle Bob** » Sun Jul 02, 2006 11:10 am

or, to keep it discrete looking, put a couple of the 160's near the throttle body.

Don't have to have 2 injectors per cylinder. The secondaries aren't as crucial in their placement, as long as they have equal feed to all the cylinders.

I know its *possible*....some of the guys on the turbo mustang forum are running 160's and have no issues other than a rich idle, but they still idle well. But they are running different engine management systems.

1fastredsc · Post by **1fastredsc** » Mon Jul 03, 2006 8:44 am

160lb/hr injectors are for like 1000rwhp. I've ran 83lb/hr injectors on a 2.7, which is enough flow for about 500-600 hp and at idle it still ran like 11 to 1 rich. Sounds like you should either not boost so much, or start staging your injectors.

jakobsladderz · Post by **jakobsladderz** » Mon Jul 03, 2006 4:13 pm

Just run pure ethanol. With the increased fuel requirements due to the lower stoichiometric air-fuel ratio (9:1 vs 14.7:1) you'll have less problems...

Another leftfield solution..

cashsaudio · Post by **cashsaudio** » Mon Jul 03, 2006 10:29 pm

Well tonite i put a cam in a 294 and now idles kinda rough but I have notice quite a change in exhaust pressure its alot more higher. So which meaning that turbo should be spooling quicker (i think). It doesn't even run all that rich either. All i did was change the cam and did all of this. I just have to advance my cam just a couple more degrees before i take it out on the road. Someone on another forum told me to try retard the timing alot more underboost. could this be ture? I thought I would need to advance timing. Let me know thanks

Jeff

Uncle Bob · Post by **Uncle Bob** » Mon Jul 03, 2006 10:34 pm

there is a lot of complexity to optimum ignition timing....let alone cam timing. The simple way to approach this is ignore the preconceived common belief that "more is better". Try different ranges, some engine configurations don't like a lot of timing.

294 is an awful lot of duration for a turbo engine. what was the old cam?