Hey Kiddies, I'm new here and have a question.First the setup. I have a 1989 lx 5.0.. Last year I had an engine rebuild. I had a kb 2.2 on my basically stock motor with 9 lb pulley and it worked pretty well. the changes- I had trickflow 170 heads installed, 90 mm lightning maf,anderson power pipe, .accufab 75 mm tb, fast 42lb, injectors,aeromotive 1000 fuel pump,MSD digi box,Powermaster 140 amp alt. had the kb rebuilt by Jon Bond Perf, with 13lb boost capacitywith bypass. compcams 284HR cam, compcam gold roller rockers,aluminum rad,blackmagic fan,high cap water pump. UPR K-member coil overs.3550 tremec tranny. I had the car on the road for about 200 miles and was getting it ready for the predetor dyno tune when my tuner, not my builder heard a noise from my motor(now after my rebuild my oil pump failed,this motor had about 50 miles on it). The guy who built it pulled the motor and had block checked ,crank turned, and I paid additional $1100.00. My new melling oil pump was free. $25.00. Wowee!. So back to getting motor dynoed. He heard a motor noise. Won't dyno it until cause is found. Got back to my builder, "No waurnty on performance engines"... So my dyno guy did a compression leakdown test on it. All cylinders were around 150 ish except for one which showed 110. On leakdown you could hear air escaping through the crankcase. So he says.. take the sc off of it and put some 21 lb injectors on it that he gave me( had chucked my 19s when the build was done). Leave sc cam 90mm maf, power pipe, tb..etc and run the crap out of it and see if the problem is just a ring that did not seat. Drive it for the summer and in sept, we will put in a 2003 4.6 turbo cobra motor he will sell me and install for $6500.00.. However, I have had trouble with the stock upper and lower intake mating, bolt problems etc, so the other day I ordered a trickflow track heat setup.. So should have it this coming Tues Wed... Long storie. My question is, does any one here think instead of using the 21 lb injectors, could I use my fast 42 lb injectors. This will be with ..again.. (90mm lightning maf..andersonpower pipe..75 mm accufabTB.. trickflow trackheat upper/lower intake..trickflow 170 heads..aeromotive 1000 fuelpump,bbk shory equal lenth header, bassani catbacks.
Newby/story/question.
- Thread starter littleboyblue
- Start date
-
Sponsors (?)
As long as the MA is "tuned" for 42 pound injectors, you'll be fine. You may have some idle issues, and may end up with a slightly fast idle, but otherwise it will be fine. Between your builder, tuner, and whoever else is touching the car, somebody is not doing something correctly. Leakdown through the crankcase sounds like a crack somewhere.
Yes... You need 42# injectors and a tune.
Running an FMU is bandaid and often asks for trouble (fuel pressure in excess of 70 psi etc).
On a side note... You should find a new engine builder.
Running an FMU is bandaid and often asks for trouble (fuel pressure in excess of 70 psi etc).
On a side note... You should find a new engine builder.
This is doubtful. Without a tune, the combination will run like crap at part power with 42s, regardless of what MAF is installed.
I bought a "bore probe and did my best to see through the sparkplug hole what the piston looked like but from what I could see, there was no issue, new, maybe inadequate tool, but I couldn't see a hole in the piston. Oh! and by the way, clean oil, sent my oil away for lab testing, and there was excess fuel in the oil, but that was about all. Thanks for the input.. Getting mixed messages on the advisability of injector size. The reason I am asking is that I have spent a LOT of money on this, and every mech I talk to tells me something different.. Mostly it was negative KB stuff, but I have read a lot of positive KB stuff. All the techs I have dealt with have wanted me to chuck the KB, which is where I am now, back to Nat fuel injection. But gotta tell you I loved that KB, before the engine rebuild. Best bolt on fun I have had.
Tune will be done of course. The dyno guy tunes race cars for the west coast road race curcuit, but his forte is newer cars, so not quite sure about his dedication to something as "old school" as my fox. Also, my son thinks I should run the 21 lb. injectors because he says the 42s were only there for the KB, as it was running lean on the dyno a few years back. But the "choke point" has always been the stock lower intake. With the trick flow heads and not installed but on it's way trickflow track heat intake this thing should flow pretty good.. So i"m thinking, with the hi-flow fuel pump(aeromotive 1000), hi-airflow 90mm maf, 75mm accufab tb, I don't want this to run lean again.also the cam is a compcam 284HR which is a supercharger cam. I am trying to be compatable with that, I really dont want to pull the motor again.
Last edited:
Well you should know and be able to put his feet to the fire right away if there are drivability issues.
Just ensure that when you get to the dyno that you do some part power runs and adjustments and not just wide open throttle.
Engine is getting track heat settup on today. KB psi was 13.. I have 21,39, 42 lb injectors.. I'm not sure what to run behind the 90mm lightning maf,anderson power pipe, 75mm accufab tb.. 21s are going on today.
You need the 42# injectors with no Fuel Management Unit (FMU) and it needs to be correctly tuned.
I would imagine that you're running the 21# with an FMU? Is this the 2.1L kit with the external by-pass or the the Flowzilla kit with the internal by-pass?
I hope it's the latter and if so, you might consider getting a larger throttle body.
I would imagine that you're running the 21# with an FMU? Is this the 2.1L kit with the external by-pass or the the Flowzilla kit with the internal by-pass?
I hope it's the latter and if so, you might consider getting a larger throttle body.
Sorry Bud.. I have a 2.2 with an external bypass. I took the sc off. The top end is going to be a Trick Flow Track heat setup.. We are putting 21s on tomorrow. Didn't get done today, awaiting gaskets.. Intake front section is a Lightning 90mm mass air, Anderson power pipe 75mm accufab. aeromotive 1000 fuel pump, trickflow 170 heads, the cam is a comp cam 284 hr. I don,t know how thats going to work as it is a super charger cam . All these parts have less than 200 miles on them.
Bringing it back some what to stock because he noticed a noise when it was getting it prepped for a final dyno. Compression was down to 110 in back drivers side cylinder. 8?.. Anyhow.. off comes the KB2.2, and on goes new trickflow track heat. The stock lower was a chokepoint and someone screwed up the bolt holes, so new intake. I had spent so much on this settup, I was hoping to keep the maf, anderson,accufab,plus cam because I didnt want to pull the engine again.. Drive pee out of it hoping to seat the ring if that was the prob., then in the fall(right around corner). Was to put 2003 cobra 4.6 turboed in, however now looks like it will be coyote 5.0... Hoping someone here would know if this combo will work.
hey guys ..one more thing... Does anyone have a picture of the hose routing of the original 1989 5.0 intake vacuum lines... Or even better, a vacuum routing pic of the track heat setup? I had the super charger on so long I cant rember the routing of the lines.
Similar threads
