how to make a 5.9 slower

[GLHSHELBY]

how to make a 5.9 slower???
1st run in 2004 9.35@ 70 stock
K&n fipk 2004 9.25@70
fipk,mp computer 2004 9.45 @70

from 2005-2009 it ran continuous 9.45`s @ 70

tonight after installing msaine trans,headers,3`` mandrel exhaust,M1,BBK tb,msd ignition I run a 10.14@68 three times in a row .

I`ve never seen such a thing run slower with mods.I was hoping for 8`s and I get 10`s. I seriously done with throwing money into this for it to run slower however I`d like to find the reasoning for the power loss.

Check engine light is on because of no cat but that`s the only reason.I haven`t messed with timing . Any help will be much appreciated.It has also lost maybe 15-20 lbs by switching intakes,headers,and stuff.

[bakes]

You need to put a wide band in and see what happened to your AFR. Im betting you leaning it out now with all the mods as you increase the air flow.

[shayne]

i would bet on the intake playing a big part in lost low end torque slowing you down. m1 intakes i have seen for the magnums are single plane, they have never been the best for low end torque on any motor, and with a truck you need the torque like what you get from a good dual plane intake manifold to get you moving. also dont overlook drivetrain wear on the driveshafts, i see you must mean your awd gc.

[shadow88]

How were the air and track conditions on each track visit? Something as simple as lower barometric pressure can easily explain the higher times and slower traps.

[Vigo]

The intake could be a big part of it. I wouldnt dare try switching to an m1 unless i was revving to 6+ and had at LEAST a cam. Otherwise it doesnt really suit the powerband.

Dont get me wrong, the stock intake is a POS, but unless you've got a looser converter, cam, headers, 6k+ rev limiter and maybe even a little head porting i wouldnt bother with the m1. Just my .02.

[GLHSHELBY]

The intake could be a big part of it. I wouldnt dare try switching to an m1 unless i was revving to 6+ and had at LEAST a cam. Otherwise it doesnt really suit the powerband.

Dont get me wrong, the stock intake is a POS, but unless you've got a looser converter, cam, headers, 6k+ rev limiter and maybe even a little head porting i wouldnt bother with the m1. Just my .02.
yea I know the M1 really didn`t help but my jeep had the common 318/360 plenum leak,been that way for at least 6 years and I`ve had the M1 for over 7 years. Figured I`d just fix the leak by putting it on. I know I need a cam and stuff to get the power from it. I launched with OD off and not changing gears because I can`t change them yet. The cable isn`t aligning right and needs replacing. However with this in gear IMO I don`t think it should be affecting my times.
The trans does have a 2800 stall now,and headers.
I really didn`t expect it to be a lot faster ,just a little.However I definitely didn`t expect it to be a 1/2 second slower.
People on the jeep list say all I need is a tune and that it`s just past the performance level of the mp computer in it now. It was very humid tonight and my cousins said their trucks ran a good bit slower than usual also.

---------- Post added at 01:44 AM ---------- Previous post was at 01:40 AM ----------


i would bet on the intake playing a big part in lost low end torque slowing you down. m1 intakes i have seen for the magnums are single plane, they have never been the best for low end torque on any motor, and with a truck you need the torque like what you get from a good dual plane intake manifold to get you moving. also dont overlook drivetrain wear on the driveshafts, i see you must mean your awd gc.
I knew it was a trade-off putting the m1 on but I figured my trans,headers,bbk TB, would take up the slack.

[GLHSHELBY]

The intake could be a big part of it. I wouldnt dare try switching to an m1 unless i was revving to 6+ and had at LEAST a cam. Otherwise it doesnt really suit the powerband.

Dont get me wrong, the stock intake is a POS, but unless you've got a looser converter, cam, headers, 6k+ rev limiter and maybe even a little head porting i wouldnt bother with the m1. Just my .02.
I still don`t think it would have lost that much power though. My TV cable was missing a spring also. The socalled `mechanic` that hooked everything up screwed up things IMO. I`m no mechanic either but I`m trying to fix what I know is wrong. I wish I knew a local mechanic to use though as I`m sure they could spot something right away.

[Juggy]

id ditch the MP computer and get something different

did u get the comp new or used?? have you ever heard about the "death flash" ??? altho i wouldnt think the MP computer would suffer from that

have you tried putting the stock comp back in and see how fast you go?

[GLHS592]

I'm reminded of the Dogkota article Hot Rod ran a few years ago. They threw every mod you can think of at a Dakota R/T and it didn't pick up much power. You need an SCT tune or something similar to make Magnum powered trucks/Jeeps run with just about any mod.

[glhs0426]

Whatever you do don't "adjust the timing". The distributor in the magnum engine sets the injector sync and only directs the spark to the correct plug. Moving the distributor out of the correct range only puts the rotor out of phase with the spark plug tower.

Most stock cammed magnum engines perform best between -4* to -6* sync, but every combination is different. My 10.3:1 5.9L liked -4* with a modified stock intake/shorty headers, and 0* with the 4bbl M1/full length headers.

There is an easy procedure to set sync with the scan tool, but there is also a do it yourself procedure that can be done with a multimeter and setting the crankshaft a the V8 mark just past TDC.

You have all the makings of an awesome truck minus a good camshaft and tune. The intake, headers, exhaust, and converter are begging for them.

[GLHSHELBY]

id ditch the MP computer and get something different

did u get the comp new or used?? have you ever heard about the "death flash" ??? altho i wouldnt think the MP computer would suffer from that
have you tried putting the stock comp back in and see how fast you go?
I definitely will be getting the SCT as soon as funds allow me to. Looks like 20 people have responded with maybe 17 saying SCT,and 3 saying something is wrong.I believe they are all right. I had to compare my black 5.9(the one I`m working on) to my silver 5.9 and my old 97 5.2 and noticed he installed quite a few things upside down or different.Been working all day to fix this stuff. My 4wd levers were upside down,no spring on the TV cable,the starter shield was hitting the flywheel.
I haven`t tried putting the stock computer back in,yea I`ve heard of the death flash and neither of mine have it.

[GLHSHELBY]

You have all the makings of an awesome truck minus a good camshaft and tune. The intake, headers, exhaust, and converter are begging for them.
Thanks.I also put some E-code glass lights and piaa micro ff fogs on it. The lighting is soo much better now. It really needs a cam,possibly roller rockers,and a good set of heads. That`s gonna have to wait til I get a job though. That will be my next steps after the SCT.

[Juggy]

Ill have to ask my sisters ex fiancee what programmer he had used. it might have been the SCT.


but his truck got the death flash (drops timing 4 degrees from stock) and when he put the computer programmer in the truck picked up some NOTICEABLE POWER. meaning that the truck could barely spin the tires with the stock comp, and could now light them up with ease!!

alls i know was it had 3 different tunes and it basically exchanged the stock bin into the programmer and threw the hi po bin on. which is one thing to look out for because people will actually SELL them after they take the perf cal and dump the stocker back on....and you end up getting screwed.

[440dart]

GET a REAL 5.9 you know the one without sparkplugs lol probley double the milage and power just sayin lol

[PunKid]

I'm reminded of the Dogkota article Hot Rod ran a few years ago. They threw every mod you can think of at a Dakota R/T and it didn't pick up much power. You need an SCT tune or something similar to make Magnum powered trucks/Jeeps run with just about any mod.

I have seen a similar situation. I worked at a speed shop with a Dyno, and we were running a modified Dakota R/T (basic bolt ons, exhuast, intake, computer) and he had some very low numbers (can remember specifics). Long and short of it, my boss owned a bone stock Dakota R/T so we ran that just to see the differences, and the stock R/T had both better HP and Torque.

[Force Fed Mopar]

Definitely you need a tune. And you need a wideband to tune it properly. Wish you were closer to me so I could help more. You need to bring it up to Greer one night so I can look it over and maybe we can fiddle around w/ it some. Dunno what the trans is shifting at now but I bet it needs to shift a lot higher to keep it in the power band better.

[Vigo]

All stock, i think they upshift at 4800.