Suggestion for cam?

[John D]

I have a 2005 and I am thinking about doing a cam on it. The car currently has Belanger headers, HF cats, and 3" catback, a BBK throttle body, 170 degree thermostat, and a tune from Torrie at Unleashed tuning. Any suggestions on where I can get a cam for it? I think if doing the cam, I'd have to upgrade the valve springs and lifters. Is there anything else that would have to be done? I don't have a specific goal in terms of power but some more power while maintaining drivability on the street as well as for any lapping days I do.

Thanks,

 

[MoparMap]

Depends. Ultimately speaking I think it comes down to what you consider drivability. For the gen 3, you could put something like the comp coupe cam in and maybe not affect things too much. I think Prefix sells them on their website now. Alternatively, there are several shops out there that probably have custom grinds. I put one from Viper Specialty in my car when I rebuilt my engine after the first spun bearing as I found I had a damaged lobe on the stock cam and figured why not upgrade. It's definitely potent as between the cam and the new tune I gained something like 50 hp. However, it did affect how the car drives around town for little stuff like running errands. Below 2000 rpm the car really bucks a lot more than stock.

It's also way louder than I would have expected for just a cam swap. Bought the car originally with just a Borla catback on it and it had a very pleasant sound. Swapped on a set of M&M headers and lost the cats a few years later when I found some for a good deal. That changed the tone more than the volume, though probably made it a touch louder just losing cats. With the cam swap the 2.5" setup sounded like it was struggling, but was also noticeably louder. Thought a 3" setup with cats might be the ticket to quiet it down a tad as the 2.5" was very pulse-y and I was thinking the 3" might smooth it out so you didn't hear every pulse quite so much. Found out the Mopar 3" race kit is way longer than the 2.5", so couldn't put cats on it after all. On the one hand I love the sound, but on the other I feel it might be a little obnoxious.

For the swap I did have to replace the springs and pushrods, but stock lifters are still okay. I put in a new set as one or two of mine looked like they might have some small scratches on them.

However, if your idea of drivability is taking it out on a nice weekend and cruising the backroads, then I don't think you'd notice any real difference if you had my cam, aside from the extra power. I'm the weirdo that drives my Viper everywhere and uses it to run errands and get groceries around town.

 

[John D]

Depends. Ultimately speaking I think it comes down to what you consider drivability. For the gen 3, you could put something like the comp coupe cam in and maybe not affect things too much. I think Prefix sells them on their website now. Alternatively, there are several shops out there that probably have custom grinds. I put one from Viper Specialty in my car when I rebuilt my engine after the first spun bearing as I found I had a damaged lobe on the stock cam and figured why not upgrade. It's definitely potent as between the cam and the new tune I gained something like 50 hp. However, it did affect how the car drives around town for little stuff like running errands. Below 2000 rpm the car really bucks a lot more than stock.

It's also way louder than I would have expected for just a cam swap. Bought the car originally with just a Borla catback on it and it had a very pleasant sound. Swapped on a set of M&M headers and lost the cats a few years later when I found some for a good deal. That changed the tone more than the volume, though probably made it a touch louder just losing cats. With the cam swap the 2.5" setup sounded like it was struggling, but was also noticeably louder. Thought a 3" setup with cats might be the ticket to quiet it down a tad as the 2.5" was very pulse-y and I was thinking the 3" might smooth it out so you didn't hear every pulse quite so much. Found out the Mopar 3" race kit is way longer than the 2.5", so couldn't put cats on it after all. On the one hand I love the sound, but on the other I feel it might be a little obnoxious.

For the swap I did have to replace the springs and pushrods, but stock lifters are still okay. I put in a new set as one or two of mine looked like they might have some small scratches on them.

However, if you're idea of drivability is taking it out on a nice weekend and cruising the backroads, then I don't think you'd notice any real difference if you had my cam, aside from the extra power. I'm the weirdo that drives my Viper everywhere and uses it to run errands and get groceries around town.

Thanks for the feedback. I'm a weirdo like you that drives it everywhere daily. I guess it makes sense that it would buck at low rpms considering everyone comments on the lumpy idle sound of a cammed car. I'll have to give this some thought

 

[MoparMap]

Yeah, I read comments all the time of people saying "it drives just like stock, but with way more power". I don't know how those people drive their cars, but I'd wager it's nowhere near how I drive mine, lol. There's always going to be a tradeoff, especially with a cam. I'm guessing ported heads or something like that is probably almost a universal benefit, but the cam really defines the character of an engine. Maybe if something was just horrendously restrictive from the factory then you could put in a larger one and only see benefits, but the Viper is pretty potent right off the showroom floor, so changing things up is likely going to mean sacrificing something somewhere else.

I've been tempted to put a stock cam back in it, but some of it just comes down to getting used to the new setup as well. I used to be able to just let out the clutch and not even touch the throttle and the car would pull away from stoplights and such just fine, but that's certainly not been my experience anymore. It takes a little more finesse and maybe not upshifting to the next gear when cruising around town like I was used to, but it's just something I'll learn to live with. I think the cam itself is a great piece, don't get me wrong. I think I just had expectations that were unrealistic at the time. I basically took a gen 3 engine out of my car and put a gen 4 back in its place with the power I've got now, it's just a little more of a racecar to drive around town than it used to be.

 

[txrunner]

I think the 708 cam (or 708r) is a popular choice for street. Good time to do the heads, pushrods & rockers too if the budget allows. Otherwise a cam is an expensive upgrade for minimal gains & a certain sound alone IMHO

 

[Viper Specialty]

Yeah, I read comments all the time of people saying "it drives just like stock, but with way more power". I don't know how those people drive their cars, but I'd wager it's nowhere near how I drive mine, lol. There's always going to be a tradeoff, especially with a cam. I'm guessing ported heads or something like that is probably almost a universal benefit, but the cam really defines the character of an engine. Maybe if something was just horrendously restrictive from the factory then you could put in a larger one and only see benefits, but the Viper is pretty potent right off the showroom floor, so changing things up is likely going to mean sacrificing something somewhere else.

I've been tempted to put a stock cam back in it, but some of it just comes down to getting used to the new setup as well. I used to be able to just let out the clutch and not even touch the throttle and the car would pull away from stoplights and such just fine, but that's certainly not been my experience anymore. It takes a little more finesse and maybe not upshifting to the next gear when cruising around town like I was used to, but it's just something I'll learn to live with. I think the cam itself is a great piece, don't get me wrong. I think I just had expectations that were unrealistic at the time. I basically took a gen 3 engine out of my car and put a gen 4 back in its place with the power I've got now, it's just a little more of a racecar to drive around town than it used to be.

The particular cam you have is quite mild. You should not be having any bucking issues that would be much different than stock, certainly not enough to consider a swap back. Generally under 2K in low gears should never be a steady-state cruise... you accell, clutch and coast. If you are trying, you might be entering/leaving idle control mode. If thats the case, I can certainly pull some timing in that area if you can log the approximate vacuum the buck is occuring in. This would not affect anything that was done on the dyno, just this single issue. Its worth a shot... without actually driving the car I cannot tell what your expectations are versus the reality of how its acting... but I generally dont tolerate less than stock-like drivability, and that cam certainly can attain it.

 

[MoparMap]

The particular cam you have is quite mild. You should not be having any bucking issues that would be much different than stock, certainly not enough to consider a swap back. Generally under 2K in low gears should never be a steady-state cruise... you accell, clutch and coast. If you are trying, you might be entering/leaving idle control mode. If thats the case, I can certainly pull some timing in that area if you can log the approximate vacuum the buck is occuring in. This would not affect anything that was done on the dyno, just this single issue. Its worth a shot... without actually driving the car I cannot tell what your expectations are versus the reality of how its acting... but I generally dont tolerate less than stock-like drivability, and that cam certainly can attain it.

Okay, I'll have to think about that one. I suppose it's entirely possible I just didn't get the cam timed right as well, but I know I checked it several times and am fairly sure I got it as close as I could with the offset keys at my disposal. I know a real adjustable timing gear is the better way to go, but no one had any available when I first swapped the cam.

As for cruising rpm, 30-40 mph around town for me is steady-state cruise right at or under 2k rpm. There are long enough stretches of road around here where I will be just barely on the throttle and I can just start to feel it sort of surge on me. I actually had it do it to me in 5th gear on the highway the other day randomly, which it's never done before, but also hasn't really done since. It should have started with a fresh adaptive table after the rebuild as the battery was unplugged for several months during my rebuild, so that maybe had something to do with it as well. Strangely enough, I pulled the battery again the other day because I think it's got a weak cell and could be the reason for my starting problems I see from time to time and after putting it back in the car seems to drive smoother than before, so wondering if I just got some weird adaptives in there on the first drives. I'll have to see about doing some logging though. Wouldn't mind it being a hair more reserved around town. I also realize it's certainly difficult to explain feeling and stuff over emails and even the phone, it's something I agree you just have to experience in person. Maybe I can catch it in a datalog though.