Hello

I have a 98 Dodge ram SS/T 5.9L 109k miles. With a Kenne Bell supercharger, headers, flowmaster exhaust exits to the passanger door.
Well I bought this truck used and didn't really test it out (kind of like buying a house without looking at it). I thought it had a simple spark plug misfire
and thought it would be a quickfix, I have already spent over $700 in labor for changing plugs mainly because the Kenne Bell supercharger is in the way the cap and rotor. A compression test was done,
cyl.1 150 psi.
cyl. 2 140 psi.
cyl.3 160 psi.
cyl.4 150 psi.
cyl.5 95 psi.
cyl.6 150 psi.
cyl.7 150 psi.
cyl.8 140 psi.
Cyl. 5 is the one that is low, I don’t know what the psi is suppose to be at. The shop said it might be a valve. So I’m tired of spending money on changing plugs, and would like to fix the problem, I’m still making payments on the truck so I can’t go the 408 stroker route( right now). First choice is to by a used engine ($800) out of a junked truck and change out gaskets; I know it will eventually go bad because of the boost. Second choice is pull my engine apart and find out what’s going on. I’m trying to consider cost, which way will be cheaper (I have a buddy mechanic that will be doing the labor, and wont be no where near the cost of pulg changes)? Now what my truck is doing is misfiring, And what I have also noticed is that when driving and the transmission shifts to a higher gear and the rpm drops under 2000 it shakes unless I accelerate to go above 2000 rpm or take of the O/D to shift into lower gear making the rpm go up it stops shaking, (don’t know if that narrows the problem). Also when at a dead stop and I slam on the gas it doesn’t move for about a second them it moves slowly. It almost lags at all speeds and seems like a slug (don’t know if that do to the Kenne Bell not having an intercooler) but the boost is always there, but builds rpm really slow, I can probably count to 100 before the rpm builds from 3000 to 4000 rpm LOL (im just used to my nitrous assisted ls1 T/A). Also if you have any advice in gasket brands in combination with my supercharger please comment because in order to change the head gaskets I have to pull of the supercharger NOT FUN, so I’d like to do it right the first time. I don’t know if it’s the heads pistons or what if you guys or gals have any clues let me know.
Another question, Are 94-97 5.9 the same as 98, I seen that the spark plug heat range is different? The reasin I aske is because I have the kenne Bell computer that recailibrates the pcm so I don't know if that will be a problem?
Sorry for the long story but I wanted to give detail Altough I know Im misssing the important things that I wanted to mention but oh well I guess I'll remeber later.
Thanks In advance for any help

 

ok the compression test does identify which hole is giving you hell. now what really needs to be done is a leak down test or simply pressurize that cylinder. really easy-- use a compression test, but before you install the end into the spark plug hole, removed the shrader valve. installed the compression tester and use a air hose to connect to the end instead of using the gauge. this step will fill the cylinder in question with air, try to get around 125psi or higher of pressure injected into the cylinder.
now once this is done, you will hear air coming from 1 of 3 places. dip stick tube,, throttle body, or tail pipe. if it come out of the dip stick, go get another motor, if it comes out of the throttle body, you need a intake valve. if it comes out of the tail pipe, you need a exhaust valve. those trucks are famous for the heads cracking from one valve seat to the other. if you dontknow what to look for you can easily pass over it.
if i had to guess, your motor is probably fine, you just need to go by a set of reman heads and be done with it.

 

First off, since you own a supercharged car you should probably own a commpesion tester. Also listen to Dodgeboy about the leakdown test. I had a very similar problem and mine turned out to be nothing but a loose rocker arm. Dodgeboy is right about the heads on the 5.9's too, fairly week. The pushrods are also known for popping out of place if driven hard.

You should also get a mechanic that knows supercharged engines b/c most mechanics don't. Whoever did the work on your car probably put in the stock plugs which have protruded tips. You do not want protruded tips on a plug if it is supercharged (or platinums). The plugs could have caused the problem. Did you hear any sort of pinging sound before the problem started?

Also did the other problems start before this one or has all of thie stuff you mentioned started after you realized you had a dead cylinder?

Until you get the misfire resolvd you should not drive the truck again. Once it is fixed you should go and get a dyno test. Not to know what the power is (a nice side result though) but to see what your air/fuel ratio is. Under normal driving conditions you should be around 14.7 but under boost and load it should be around 12. Anything under load above 14 and you will be risking engine damage.

 

Damm I should have done a leak down test.
Well My buddy toredown the engine, and visualy the heads look alright. My buddy pointed out a valve in cylinder #7 looking burnt. And the small valve on cylinder #3 looks worn down. He said to take them to a machine shop to get inspected. I'll try to get some pics so that you guys can give me your opinion's. As for the block it got dark outside so he couldn't really see to well, but I seen the cylinder walls have some x desinged scracht's which he said was normal. But that he would check them tommarow. None of the pistons look cracked. He put cylinder #5 up and noticed that it had slight play. The head gaskets didn't look blown out.
So we went on to the theroy of maybe the block needs a rebuild??? And started talking about how much a rebuild would cost at machine shop. I'm not to sure about this but what do you think about a rebuild???? Can forged pistons be put in without stroking the engine??? Another thing we noticed is that block looks like a used drop-in because it has chalk writing on the intake and block????
I don't know what is going on here, but im hearing about kenne bell superchargers and there computer's not being the best, im starting to think it has something to do with that?[/align]

 

Actually the problem's have been there since the day I bought it. I know not good, but look at it this way, at least im trying to take care of it and not let another dodge down, when I can be out there whopping on my buddies lightning's in my ss/t LOLj/k.

Another thing I always forgot to mention is that when I would rev the engine in park or neutral after reving the rpm would come down real slow. Dont know if that means anything. Maybe the idle control or TPS, not sure???

 

So my buddy pulled out the block.
He took me to a machine shop to get a estimate, the shop owner took my info and asked me if I wanted a cam I thought he meant a new cam, (after we left the shop my buddy told me hea meant a performance cam) and I said yes, he wrote down 1 cam double roller timing chain and some other stuff. It's going to be a longblock rebuild, he's going to call me tommarow to give me a quote. Should I have said no, if a differnet cam is put in won't I need a tune, I have the K/B optimizer which I think won't let me change anything?
Should I have forged piston's put in? Will there be a big price difference in forged pistons vs stock, and what will the performance difference be? Is .30 over what I will need and dished is for boost right??? Is there an advantage in puttingforged piston's.
Is there a mod that can be done to the keg intake manifold for better flow?
What kind of gaskets should I use? I have seen the mopar and fel-pro gasket kit's? Will I need different head gaskets because of the boost? If so what kind should I use?
Are pre98 ram fuel injectors different lbs? The one's that we pulled off the manifold were real hard to pull out? Im not sure if the engine has been swaped and maybe have different lb ratings and causing the kb optimizer to act different?? They have a mopar part #. Just a thought.

A shop that I called said he charges $1300 for a longblock rebuild.
To be honest I don't really want to do a rebuild because I don't see any performance gains from it. But maybe im worng. I guess im kind of scared of doing a rebuild and the problem still not being fixed, Since I thought the problem was going to be visible in the heads, like crack's or broken springs. And mainly because the truck has never ran good form the day I bought it (stupid of me).But some valves look burnt. I think my porblem is that I read to much on these forums LOL.
Im going to load everything in my dads truck tommarow and get a quote at a shop out of town. I was caught off gurad with the machine shop I went to, What should I ask him to do different as far as cam, piston's, and gasket's. Or if I go to a differnet shop what should I tell them I want done to it. And should I metion I am using a little bit of boost.
Oh and as for what I plan on using the truck for since that's important too. I'm going to use this as my street cruiser, I have 98 n20 trans am as my track car, but occasionly I would like to take it down the track. So street/strip car. I do like hitting it on the street and missing with my buddie's lighting's, but I don't expect to be as fast as them untill I get a 408 stroker j/k LOL.

I will try to get pics of everything on here by 11 am tommarow or should I say today.
Sorry about asking one too many question's.
Thanks to everyone for there time and help.

 

As long as it's a mild cam you should be alright. And forged pistons are DEFINATLY a good idea. You will notice someperformance gains, but the major benefit is their ability to discharge heat. The stockers hold heat in and this causes hotter combustion chamber temps which will cause detonation, which can casue some serious damage. The forged will get rid of the heat, allowing you to run more boost. They'll also alow you to advance some timing (if you had a standalone timing calibrator)which would increase HP by quite a bit. The Optimizer is basically junk anyways. It pulls too muchtiming, and adds too much fuel (to be safe) You'd be better off with an aftermarket FMU and timing calibrator or a standalone fuel and timing calibrator like a Megasquirt or Split Second FTC-1. It would gain you quite a bit of power, allow full tunability, and let you take advantage of that new cam.

my .002

 

Here are my new question's to the stock longblock rebuild???

What kind of gasket's should I use with the rebuild? It will be a pain to have to change the head gaskets every couple months.LOL I have the big pulley installed which I think is 6lbs and MIGHT change it to the smaller one which I think is 8lbs.

Im also thinking about doing forged piston's, and I have some question's since im the brightest when it comes down to compression and the more delicate stuff.
Are there any advantages to having it bored .30 over, if so what are they? As for the compression, will it have to be changed? Like have dished piston's insted of flat or something else? I only plan on keeping the boost @ 6lbs maybe changing out the pulley for the 8lbs if possible. I don't know if the 6lbs or maybe 8lbs will get the compression to where it needs to be with dished piston's, and the stock heads? Or if dished is only for bigger power adders? Or will I be okay with the flat's?

I would also like to do a standalone system but it going to cost me an arm.lol

 

 

My standalone cost me about $700. I thought it was extremely well worth it. Being bored .30 will decrease your compression slughtly, which will allow you to run the flat pistons and you shouldnt have any problems.Dished pistons would lower the compression even more, but it may be too low and you will probably lose power. You'll also be able to cram a little more air and fuel in there so you might notice some performance increase with the bore. Gaskets... well I'm not sure, I', still running my stockers. Havn't blown them out yet. I'm running the 8lb pulley, but at the manifold I'm reading 10Lbs with it!