Question for guys who actually have the the Roush Kit

Hammerhead13579

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Here are the results of a spicy tune on my Whipple'd car in 100+ degree heat on the stock motor, with several back to back runs. I was at around 750whp. Admittedly, NOT an apple's to apples comparrison, but the Whipple stage 2 intercooler is miles better than the Roush set-up and forced induction from a positive displacement supercharger is going to build heat at the ringland when you are running hard, regardless of which brand it is. Your results may vary, but if he has the funds for an Interchiller, why would someone tell him he doesn't want one? It will go a long way to mitigating his concerns about engine failure. The cats situation is a whole 'nother can of worms.

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Yeahhh.....don't care. Cars blow up all the time for different reasons. Not even the same fuel, same blower, same tune, etc. Clearly, you are biased because you had an unfortunate experience.
My advise to the noob was based on my experience and my knowledge. He immediately jumped to "needing an interchiller" and I merely said he doesn't need one if he isn't racing the car. I literally italicized that in my previous post. I also said he needs to do his own research and that in the end it's his decision...
Also, are people opposed to saving money here? Wouldn't people want to keep $2,000 in their bank accounts?
Is everyone keeping their cars until 100k plus on the odometer?
I sell my cars every 2-4 years so I couldn't care less if the engine doesn't perform optimally when it's on the 4th owner...

Also...he never said he had concerns about engine failure
 

engineermike

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Couple comments on the last page or two of posts.....

- The Roush car that popped a couple of engines was not running a Roush cal or stock cats. Correct me if I'm wrong. I don't know that I've heard of any popped engines on the stock Roush cal and stock cats.
- The boost may have dropped with the headers but that doesn't mean it's ok to put a smaller pulley. The blower is flowing the same air at the same temp, so the cylinder conditions haven't changed appreciably in such a way that would allow more boost.
- Some aftermarket tuners actually lower boost 1-2 pulley sizes if you're on pump gas and claim power gains.
- No way I'd increase boost on the Roush setup on true pump gas. It's already running more boost than Whipple Stage 2.
- On pump gas, the interchiller is probably the best thing you can do for a Roush setup. Rule of thumb is you can add 1 deg of timing for every 10-15 deg colder IAT. So as long as your tune will add timing as IAT drops, you'll gain power even if you're already below the "heat soak" range.
- EGT is a function of IAT and even moreso, timing retard. So when Roush runs a hot IAT, it makes things worse for the cats. Roush pulls timing with IAT, as it should, but this adds even more heat to the cats.
- A tune alone can gain some power, but I trust basically no aftermarket tuners after the garbage I've seen. You can add a decent bit of performance by retarding the intake cam at WOT and increasing shift points and firmness a bit. If an interchiller is added, you can ensure it's adding timing at the colder charge temps. These are pretty easy changes to make and I can guide a self-tuner through it. You can do this stuff yourself for about $250 with PCMTec software.
 

HKusp

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Yeahhh.....don't care. Cars blow up all the time for different reasons. Not even the same fuel, same blower, same tune, etc. Clearly, you are biased because you had an unfortunate experience.
My advise to the noob was based on my experience and my knowledge. He immediately jumped to "needing an interchiller" and I merely said he doesn't need one if he isn't racing the car. I literally italicized that in my previous post. I also said he needs to do his own research and that in the end it's his decision...
Also, are people opposed to saving money here? Wouldn't people want to keep $2,000 in their bank accounts?
Is everyone keeping their cars until 100k plus on the odometer?
I sell my cars every 2-4 years so I couldn't care less if the engine doesn't perform optimally when it's on the 4th owner...

Also...he never said he had concerns about engine failure
Okay. Duly noted. You do you.
 
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Couple comments on the last page or two of posts.....

- The Roush car that popped a couple of engines was not running a Roush cal or stock cats. Correct me if I'm wrong. I don't know that I've heard of any popped engines on the stock Roush cal and stock cats.
- The boost may have dropped with the headers but that doesn't mean it's ok to put a smaller pulley. The blower is flowing the same air at the same temp, so the cylinder conditions haven't changed appreciably in such a way that would allow more boost.
- Some aftermarket tuners actually lower boost 1-2 pulley sizes if you're on pump gas and claim power gains.
- No way I'd increase boost on the Roush setup on true pump gas. It's already running more boost than Whipple Stage 2.
- On pump gas, the interchiller is probably the best thing you can do for a Roush setup. Rule of thumb is you can add 1 deg of timing for every 10-15 deg colder IAT. So as long as your tune will add timing as IAT drops, you'll gain power even if you're already below the "heat soak" range.
- EGT is a function of IAT and even moreso, timing retard. So when Roush runs a hot IAT, it makes things worse for the cats. Roush pulls timing with IAT, as it should, but this adds even more heat to the cats.
- A tune alone can gain some power, but I trust basically no aftermarket tuners after the garbage I've seen. You can add a decent bit of performance by retarding the intake cam at WOT and increasing shift points and firmness a bit. If an interchiller is added, you can ensure it's adding timing at the colder charge temps. These are pretty easy changes to make and I can guide a self-tuner through it. You can do this stuff yourself for about $250 with PCMTec software.
Great info appreciate it thanks ! Ill hold off on the pulley and go with the chiller. Was thinking of going with palm beach dyno for tuning, or just stick with the roush ? maybe there is a different thread for that as well ?
 

Zrussian13

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Couple comments on the last page or two of posts.....

- The Roush car that popped a couple of engines was not running a Roush cal or stock cats. Correct me if I'm wrong. I don't know that I've heard of any popped engines on the stock Roush cal and stock cats.
- The boost may have dropped with the headers but that doesn't mean it's ok to put a smaller pulley. The blower is flowing the same air at the same temp, so the cylinder conditions haven't changed appreciably in such a way that would allow more boost.
- Some aftermarket tuners actually lower boost 1-2 pulley sizes if you're on pump gas and claim power gains.
- No way I'd increase boost on the Roush setup on true pump gas. It's already running more boost than Whipple Stage 2.
- On pump gas, the interchiller is probably the best thing you can do for a Roush setup. Rule of thumb is you can add 1 deg of timing for every 10-15 deg colder IAT. So as long as your tune will add timing as IAT drops, you'll gain power even if you're already below the "heat soak" range.
- EGT is a function of IAT and even moreso, timing retard. So when Roush runs a hot IAT, it makes things worse for the cats. Roush pulls timing with IAT, as it should, but this adds even more heat to the cats.
- A tune alone can gain some power, but I trust basically no aftermarket tuners after the garbage I've seen. You can add a decent bit of performance by retarding the intake cam at WOT and increasing shift points and firmness a bit. If an interchiller is added, you can ensure it's adding timing at the colder charge temps. These are pretty easy changes to make and I can guide a self-tuner through it. You can do this stuff yourself for about $250 with PCMTec software.
I could be wrong too but I'm pretty sure @hlfbkd420 blew the first engine on the stock tune/ cats. I know he had headers when the second one popped.
 

The Watchman

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I drove my whip before and after Interchiller install and it’s like night and day…all for the better.

Interchiller can and will rectify 90% of the problems associated with this Roush kit.

The Hellcats have a very similar system which is built in stock.

I drive the heck out of my car in the hottest temps doing back to back WOT pulls and IAT2 stay in check all the time.

Yes, you can save money and not have an Interchiller installed but we bought these cars to drive them and the FI Interchiller Stage 2 kit gives you both performance and piece of mind
 

The Watchman

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I just wanna say it’s COMPLETELY INSANE to see my boost gauge hitting 12psi over and over again in 90F temps and the car recovers quickly and is ready and begging for more…lol
 
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I drove my whip before and after Interchiller install and it’s like night and day…all for the better.

Interchiller can and will rectify 90% of the problems associated with this Roush kit.

The Hellcats have a very similar system which is built in stock.

I drive the heck out of my car in the hottest temps doing back to back WOT pulls and IAT2 stay in check all the time.

Yes, you can save money and not have an Interchiller installed but we bought these cars to drive them and the FI Interchiller Stage 2 kit gives you both performance and piece of mind
exactly my point man, my car has 8000 kms on it. Got a deal i couldnt pass up thats why I didnt mind getting the roush and dont mind spending a little bit of money out of it to get some better performance. YEs i would have loved to get to 700 rear wheel but also dont want to blow up a new car.
 

The Watchman

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exactly my point man, my car has 8000 kms on it. Got a deal i couldnt pass up thats why I didnt mind getting the roush and dont mind spending a little bit of money out of it to get some better performance. YEs i would have loved to get to 700 rear wheel but also dont want to blow up a new car.
I know my opinion in this vein is probably not popular...but, if you do the math as follows:

Roush kit-$8k
FI Interchiller Stage 2-$2500
Install-$2k

Now, you can find these parts sometimes deeply discounted, the P2 Roush kit especially.

You are basically similarly priced as the Whipple Stage 2 kit with install now. But, the Roush + Interchiller actually performs BETTER because of the cooling features.

The only downside is the Roush P2 kit for Gen 3 Coyote tops out around 12-13 psi or about 700-800whp depending on fuel.

Most of us here would not recommend anything over 12-15psi on a stock motor anyway...

Do you guys see my point here?
 

engineermike

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Great info appreciate it thanks ! Ill hold off on the pulley and go with the chiller. Was thinking of going with palm beach dyno for tuning, or just stick with the roush ? maybe there is a different thread for that as well ?
I’ve looked at dozens, maybe hundreds of aftermarket tunes. I’m partial to the Whipple supercharger (I have one of each) but nothing out there comes even close to the stock Roush calibration in terms of oem levels of control and protection. At this point I would never use an aftermarket tune outside of Roush.

As I said earlier, if you want a few hp from a tune, I’d recommend getting something like Pcmtec and making a few tweaks to it, keeping as much of the stock Roush tune as possible.
 
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yeah the OEM and drivability of the car im impressed with, if the cooling will help on pulls a bit and maybe a few other things I can tweak along the way maybe I'll be happy with it until I get something else. I'll have a look into the PCMTEC. Will also do some more tuner research. Will look long and hard before I ever pull the trigger though. Figured there would be a Roush thread for tuning but I'm guessing there not many.
 

hlfbkd420

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I could be wrong too but I'm pretty sure @hlfbkd420 blew the first engine on the stock tune/ cats. I know he had headers when the second one popped.
I ran headers starting at 2,000 miles. no tune. Tuned after two years and 12,000 miles by Wengerd. Drove car 8,000 miles in 2 months on vacation and popped cylinder 6 shortly after that...

New engine wasn't blown up by me but was a constant shit show. Pretty sure the engine from Ford had VCT issues but no one would come near it. Ford refreshed the Roush tune multiple times but I didn't know it was locked by Wengerd so they had to go all the way back to the original Ford tune first.. He was useless as well. Wanted nothing to do with it.
 

Zrussian13

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I ran headers starting at 2,000 miles. no tune. Tuned after two years and 12,000 miles by Wengerd. Drove car 8,000 miles in 2 months on vacation and popped cylinder 6 shortly after that...

New engine wasn't blown up by me but was a constant shit show. Pretty sure the engine from Ford had VCT issues but no one would come near it. Ford refreshed the Roush tune multiple times but I didn't know it was locked by Wengerd so they had to go all the way back to the original Ford tune first.. He was useless as well. Wanted nothing to do with it.
Thanks for clarifying! Be careful what you say about certain people/ tuners though. You'll have fan boys getting offended and talking more shit than when your GR smokes a 5.0....🤣🤣🤣
 

hlfbkd420

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Thanks for clarifying! Be careful what you say about certain people/ tuners though. You'll have fan boys getting offended and talking more shit than when your GR smokes a 5.0....🤣🤣🤣
I take full blame for the abuse I put that car through. I don't think it was the tune that did it anyway. You have to pay to play and I liked playing more than paying. I don't blame Wengerd for wanting nothing to do with it afterwards either.
 
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Not hearing good things about the tuned roush 😢 has anyone had a good experience with a stage 2 roush tuned on pump gas I wonder ?! 😂
 
 
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