I remember reading in the turbo kit parts list sticky that an MSD ingnition module is needed for over 6psi. Is this an absolute must? My setup will be limited to 8psi and it will be intercooled. I will also be running between 91 and 93 octane at all times. I've searched through for those running boost on the LN2, and there are those that don't have the MSD module listed in their profiles. So either they're not using it or they just didn't list it.
I don't see why you would NEED it.
I'm sure you could just gap your plugs a little smaller and be fine without it.
Granted, my ln2 knowledge isn't all that extensive....
well i run17psi without one but i kno i NEED one. it starts missing in the higher rpm hig boost levels.
DRIVE HARD OR DONT DRIVE AT ALL!!!
i dont think you need one I ran 15 psi with 94 octane fuel without having any problem on my ecotec engine! if you want to be sure juste use ngk tr7 plugs! it will help! this is what i use!
http://cavalierdomination.monchar.com
The reason, at the time, the MSD was on the list wasn't spark strength, though it helps tremendously... it was because of spark retard. Something 95% of J-body owners forget about.
If you aren't using HPTUNERS, MS or some form of standalone you need to be able to pull timing (hopefully with boost).... the standard MSD-DIS2 will pull timing at a given RPM, the higher end model will do it with boost on its own map sensor.
And yes, this is rather critical.
-Chris-
-Sweetness-
-Turbocharged-
Slowly but surely may some day win this race...
When you start missing, is it like a wall and your rpm just stop?? like if you are burning them through second and it hits 5400 rpm, it just stops right there???
or does that sound like valve float?
HP Tuners | Garrett T3/T04B | 2.5" Charge Pipes | 2.5" Downpipe | 650 Injectors | HO Manifold | Addco front/rear | Motor Mounts | HKS SSQV | Spec stage 3 | AEM UEGO Wideband | Team Green LSD | FMIC | 2.3 cams | 2.3 oil pump swap | 280WHP | Now ECOTECED
I started to pull apart my engine today and I think I found the cause for all the misfiring. When I pulled off the intake it was full of blowby liquid because I forgot to clean the catch can out. It must have been fouling the plugs like crazy. I got my other replacement engine almost ready to put in. I have the new Clevite 77 Rod bearings in and now all I have to do is put in the new oil pump and drop it in the car. I decided to keep it turbocharged and only run about 8psi of boost. Maybe this spring I will put in an MSD DIS-2 to help along with the spark.
Im not 100% sure its missing but its like it starts loosing power. In 1st, and 2nd, its fine but it feels like it starts to loose power in the top of 3rd and the top od 4th. and the sound of the exhaust changes a lil bit in 3rd and 4th. I guess it could also be because i have a small turbo pushing alot of boost. its only a 48exhaust 42compressor turbo. im trying to find a hybrid to upgrade to. but i have to change my tranny first, 2nd gear went out.
DRIVE HARD OR DONT DRIVE AT ALL!!!
oh ok, well with mine I had some obvious misfires, and then I put new plugs in and it improved alot, but didn't get great, so I am thinking some hotter spark will help.
HP Tuners | Garrett T3/T04B | 2.5" Charge Pipes | 2.5" Downpipe | 650 Injectors | HO Manifold | Addco front/rear | Motor Mounts | HKS SSQV | Spec stage 3 | AEM UEGO Wideband | Team Green LSD | FMIC | 2.3 cams | 2.3 oil pump swap | 280WHP | Now ECOTECED
ge_forcez22 wrote:oh ok, well with mine I had some obvious misfires, and then I put new plugs in and it improved alot, but didn't get great, so I am thinking some hotter spark will help.
are you running colder plugs? if so try stock plugs and if it helps out then you know you have spark issues.
_______________________
** Flat Broke Racing Inc.**
I tried tr7 and tr6, no difference there.
HP Tuners | Garrett T3/T04B | 2.5" Charge Pipes | 2.5" Downpipe | 650 Injectors | HO Manifold | Addco front/rear | Motor Mounts | HKS SSQV | Spec stage 3 | AEM UEGO Wideband | Team Green LSD | FMIC | 2.3 cams | 2.3 oil pump swap | 280WHP | Now ECOTECED
This is funny, because me and Sweetness had a very lengthy tuning conversation the other day, and a majority was on spark advance, and then this comes up. Basically, it isnt intelligent to run boost on stock ignition, no matter what, have many many many of us done it before, of course, but it isnt intelligent. Basically, think of it this way. Your compressing the air/fuel mixture obviously, which inturn heats it up. More dense/hotter air when lighted burns much quicker than a N/A air/fuel charge, hense why you want to pull timing with boost. I believe at 6200 rpms, the stock computer has a total of 26 degrees of timing advance. Now, the big catch here is, many of you guys with HPT have pulled away the spark ramp out, which has a total of I think 10 degrees of retard. If you have done this, but keep stock ignition advance, and you take your boosted motor up to 6200 rpms, you WILL detonate, I promise you, because the 10 degrees of retard isnt there anymore to save your a$$. Timing advance with boosted motors is a very large topic, and I am suprised that it is hardly talked about on these boards. As a matter of fact, tuning in general is hardly ever talked about. Thank you Chris for the numbers ^ there, I think those are what we discussed, but cant remember.
ge_forcez22 wrote:When you start missing, is it like a wall and your rpm just stop?? like if you are burning them through second and it hits 5400 rpm, it just stops right there???
or does that sound like valve float?
have you ever thought it might also being fuel related as well? or a combination of both ignition and fuel related nasty bugs?
-Trailblazer SS - not so custom 6.0L - custom intake - custom tune
- (1) 2.4L on an engine stand (1) blown trans (2) good quad trans (1) eco trans = party
I have tried changing to regular fuel.. that didn't make the issue any worse.. I have also tried 93 plus a booster... around 95-96 and the problem was exactly the same.. so over a 7 point spread it was the same... I did buy a compression tester, and will check when I get home to ensure my compression isn't too high.
HP Tuners | Garrett T3/T04B | 2.5" Charge Pipes | 2.5" Downpipe | 650 Injectors | HO Manifold | Addco front/rear | Motor Mounts | HKS SSQV | Spec stage 3 | AEM UEGO Wideband | Team Green LSD | FMIC | 2.3 cams | 2.3 oil pump swap | 280WHP | Now ECOTECED
what's the update you fix this?
try using a different fuel pressure regulator?
checked the plugs again? tested to see if each one is firing? same w/ the injectors?
-Trailblazer SS - not so custom 6.0L - custom intake - custom tune
- (1) 2.4L on an engine stand (1) blown trans (2) good quad trans (1) eco trans = party
I have checked the fuel pressure, it is consistant with what I need, the timing is gm s/c timing with sometiming removed.. I have run this car turbocharged a few years back wth gm s/c flash, injectors an map and it worked fine.
plugs are all firing and the msd is installed.. but nothing seems to be helping. the msd did make the car start better and much smoother from 1000-3000 rpm, but it still completely falls off at 5400 rpm... I think maybe the PCM is the next step... I can't think of anything else
we have changed, exhaust, crank sensor, cam sensor, injectors, ICM, coils, wires, plugs, lifters, programming... so we are thinking my computer is fubared.... I did a NO boost run (open intercooler) and it ran perfectly smooth to 6600rpm... in 2nd, 3rd, and 4th... we are thinking it is a calcualtional error when th map sees boost... but this is just a guess... I understand some of these ideas might seem dumb.. but if anyone wants to flame them.. come up with a better solution and I WILL try it.
HP Tuners | Garrett T3/T04B | 2.5" Charge Pipes | 2.5" Downpipe | 650 Injectors | HO Manifold | Addco front/rear | Motor Mounts | HKS SSQV | Spec stage 3 | AEM UEGO Wideband | Team Green LSD | FMIC | 2.3 cams | 2.3 oil pump swap | 280WHP | Now ECOTECED
what rpm are you hitting full boost? In DSM's we used to always get this issue around 5400 rpms because we weren't supplying enough fuel
full boost around 3200-3500, and fuel pressure stays at 70psi... walboro 255lph and rc 650cc
HP Tuners | Garrett T3/T04B | 2.5" Charge Pipes | 2.5" Downpipe | 650 Injectors | HO Manifold | Addco front/rear | Motor Mounts | HKS SSQV | Spec stage 3 | AEM UEGO Wideband | Team Green LSD | FMIC | 2.3 cams | 2.3 oil pump swap | 280WHP | Now ECOTECED
What have you got for checking knock retard?
With every degree of knock retard, you're losing about 5-7hp and when you get to about 7 degrees of knock retard under high boost, you're going to kill your engine with detonation?
Are any of you checking knock?
This is one of the most basic things to check when programming your fuel maps, the knock sensor and how much timing it's pulling.
Also, if you don't have an FMC with autotune, you could destroy your engine with major detonation.
The autotune function allows more fuel to be added and timing to be reduced according to your preset fuel maps.
Once you start playing with the fuel maps where your knock is most prominant, and get the autotune function to a 0 state, you're pretty much tuned and can run the boost you want without knock.
If anything, cut back on boost until you know exactly what your knock retard is doing.
Just a suggestion from someone that knows nothing about turbo's.
Misnblu
Misnblu.com
Newbie member since 1999
Thank you Dave and JBO! 
