I'm wondering how many of you that run a predator leave your truck tuned during the very cold months of winter? As posted by many people before I start to really notice the engine noise as temperatures increase and my truck is tuned w/ Predator. There is a definite difference between the noise level stock vs. predator (85hp tune).

So, is this extra noise while my truck is warming up harming my engine? By that I mean harming anymore than when the weather is 65 degrees outside.

Last winter I ran the edge module because I felt the predator made my truck too loud. I don't have the edge this year and don't feel like running stock.

Thanks in advance!

Chris

Nothing is for free, certainly not improved performance

I cant stand that rattle either. You're not the only one. Today I tuned it back to stock for a trip to the dealer and I could believe how quiet it was.

Hypertech never made it louder.

the predator advances the fuel timing, it's not nearly as bad on 40 as it is on 80.

too much timing is bad, but i don't think it's really doing any harm with just one 80hp tune
.

this is the very reason why I am sceptical about tuners that claim improved performance on all fronts. There is simply a compromise with any enhancement. I like companies who offer improved performance with little compromise in driveability and employing safety measures such as defueling to make the tune work well without further modification. Most importantly I like a tuner that is accurate about their product offering and not leaving the customer having to analyze what the company is doing with the tune. After all, I am not paying big bucks to have to do their work for them.

I understand the comprimise, but my question is why there is a such a bigger difference in noise when the weather is so much colder out.

I also know that by tuning the truck with an 85hp tune that I'm shortening the lifespan. I'm OK with that, just wondering if it's worse when the weather is cold?

thanks,
-Chris

Proper timing accounts for several things, among them, charge air temp. In cold weather, the advance causes a saturated fuel mixture that doesn't combust until further into the compression due to reduced compression temperature. The result is more of a bang than a slow burn.

This is fixable, but the box tuner companies just don't care enough. And yes, the harder hitting sound is more stress but not to be concerned.

My truck doesn't sound any different between the two.........I had mine back to stock last week !!

But our temps are pretty mild.........think the coldest it's been lately has been in the 30's !! And I only run the 65 and 40 tunes !!

People looked at me when I was crazy when I told them that the predator made my truck sound like sh!t compared to stock. Finally people are agreeing. I really hated the predator, shifted like junk, and made my truck loud. I definately think there are better alternatives to the predator.

Are you guys that are unhappy......... running the 2.0 or 2.02 ??

I recently bought a used V2.0 just to try it out, then sell, and see if I agreed with what I've heard about it...I must admit, the 85HP tune has some really good power and shifts a lot better than I thought it would...Smoke output was minimal, EGTs were ok...The 100 or 120HP tune, not sure what it is, runs very well, smokes quite a bit more than the 85HP tune, EGTs were up, and it still shifts well...Both tunes rattled a little on cold startup, mid 50s, but not that annoying for me...I guess it's just a trade-off to have the throttle response and power that it offers from the added injection timing...

Don't get me wrong, I love the predator. The power is great, I think my truck shifts good and my egts are low. I run 2.0 w/ a boost stick and almost always have the 85 tune unless I'm towing.

I was just concerned about the noise, there is a definite notice when it gets below 30. I always warm the truck up for a few minutes in that weather though. Sounds like it's not much to worry about. I'll run it through the winter... power is too much fun.

-Chris

I didnt say that I was "unhappy" the programmer because I'm not, I just dont like the rattle.

The reason the Predator tuner rattles when the ECT is low is for some reason Diablo decided to push the Main Pulse timing farther from the Pilot Pulse when the ECT is below 155 F. In some cases as much as 6 degrees more than stock (85 and 100 hp tunes), rendering the Pilot nearly useless to control the rattle. The 40 and 65 tunes only push it back 4 degrees from stock, that's why the rattle is less pronounced. Above ECT 155 F, everything goes back to stock as far as the crank angle degrees between Pilot and Main Pulse.

On a side note, I really like the Predator and I still carry it in my console even though I have EFI Live. Other than the racket from what I described above, I think this is a geat tuner and very underrated in HP.

The reason the Predator tuner rattles when the ECT is low is for some reason Diablo decided to push the Main Pulse timing farther from the Pilot Pulse when the ECT is below 155 F. In some cases as much as 6 degrees more than stock (85 and 100 hp tunes), rendering the Pilot nearly useless to control the rattle. The 40 and 65 tunes only push it back 4 degrees from stock, that's why the rattle is less pronounced. Above ECT 155 F, everything goes back to stock as far as the crank angle degrees between Pilot and Main Pulse.

On a side note, I really like the Predator and I still carry it in my console even though I have EFI Live. Other than the racket from what I described above, I think this is a geat tuner and very underrated in HP.

A little "spy" work with EFI Live....... hmmm..... ):h

Cant you just take that tune and "tweak" it to get rid of the rattle when the coolant temp is below 155?

Thanks for the info. guys........I really enjoy learning more about these trucks and tuners !! Sounds like most are running the 2.0 which may be no different than the 2.02 as far as this noise (??)!!

I haven't noticed any noise at all but I have the 2.02 , run the lower tunes,it doesn't get real cold here very often, and I always crank my truck up on cold days and let it warm up(usually my coolant temp is right above 160 when I head to work !! So that would probably explain it !!

Cant you just take that tune and "tweak" it to get rid of the rattle when the coolant temp is below 155?

Hmmm...I think so...;)

There a timing table in the ECM that is based on ECT and a modifier that is added when the ECT is below 133F. The main timing is increased ( by programmer) and then this modifier is added in cooler themps. This adds about 4 to 6 degrees and more as the themps get cooler to the total timing and you here the added knock until the ECT is above 133F, then the table is back to normal. Using EFI live can help adjust and reduce this knock in the cold or cooler weather. That added knock is not good for the engine.:badidea:
Custom tuning is the only way to go:ro)

that rattling that you hear is just the cappuccino machine that GM hid under the hood. it was an option on most late model trucks.

that rattling that you hear is just the cappuccino machine that GM hid under the hood. it was an option on most late model trucks.

I think that was only on the Escalade...

I think that was only on the Escalade...

LMAO!):h

I noticed this also. I just put the predator tune on my truck (v2.02 85hp) and the knock when the motor is cold is really bad and when it is warmed up it still has quite a bit when you first get into the throttle. I think I will run the 40 or 65 tune through the winter anyways. I have yet to try the 120hp tune:eek: My clutch hardly handles the 65hp tune as it is. I cant think that Diablo would market a product to so many truck owners that would severly harm the motor due to cold weather running???? I agree that custom tuning would be the way to go but most of us dont have the money, time, or knoledge to develop a safe, relaible custom tune.

I am running the Predator 65hp tune, and have noticed a bit more rattle on cold weather starts (and it gets cold here), but after the engine is warm, everything is normal. I always let my truck warm up for an extended period prior to driving it, and then take it easy until the engine is up to normal temps. I am not worried about the rattle, but it is quite pronounced if you drive away with a cold engine. It is still way quieter than my neighbour's Dodge :)

I noticed this also. I just put the predator tune on my truck (v2.02 85hp) and the knock when the motor is cold is really bad and when it is warmed up it still has quite a bit when you first get into the throttle. I think I will run the 40 or 65 tune through the winter anyways. I have yet to try the 120hp tune:eek: My clutch hardly handles the 65hp tune as it is. I cant think that Diablo would market a product to so many truck owners that would severly harm the motor due to cold weather running???? I agree that custom tuning would be the way to go but most of us dont have the money, time, or knoledge to develop a safe, relaible custom tune.

So why not buy an EFILive based tune from one of the many tuners around here???

I am running the Predator 65hp tune, and have noticed a bit more rattle on cold weather starts (and it gets cold here), but after the engine is warm, everything is normal. I always let my truck warm up for an extended period prior to driving it, and then take it easy until the engine is up to normal temps. I am not worried about the rattle, but it is quite pronounced if you drive away with a cold engine. It is still way quieter than my neighbour's Dodge :)

the trick is to let the truck either sit and warm up, or drive it very easy until it does hit operating temp. i'm sure the rattle is predetonation due to overfueling a cold engine.

Well, I am not sure what the Predator does with the injection timing, especially when the engine is cold. It might be interesting to take a look at the program with EFI Live. I am sure that the timing could be optimised a bit better for the cold to eliminate some of the rattle. Mind you, if you have EFI to look at the program, you probably don't need the programmer anymore :)

:iamwithst ):h I know a guy.....;)

Predator increases the main timing (for power and economy). That's ok.

There's a table in the tune that advances timing when the engine is cold. Predator did not change that table. So the tune advances timing too much when it's cold. That causes the rattle and costs power.

I guess it would have been too much work to modify the cold ECT table in the predator tune...so it runs ok in the cold.

EFILive can fix it.