That's what I assumed, but hey, if you're exhaust is loud enough it'll cover up the blower whine anyway!
Cream-puff goes Pop
- Thread starter steelskeet
- Start date
That's what I assumed, but hey, if you're exhaust is loud enough it'll cover up the blower whine anyway!
KNG SNKE
Enthusiast
Correct, you can only hear the whine at cruising speeds with the windows up. BUT, when you stomp the gas whoever is in front of you hears the jet before the rumble, makes for good videos too.
rw99
Enthusiast
Houston, you have a problem.
KNG SNKE
Enthusiast
What problem would that be? Works just fine.
rw99
Enthusiast
My experience is SBC-oriented, so please forgive me if I'm drawing unfair comparisons. But it seems unreasonable to expect longevity and performance from an FI application that has no intercooler/aftercooler. Especially without a fully forged motor. But I don't know the Roe kit or its record among you guys, and I'll be the first to say "if it works, it works".
As mentioned above, I think we're on the same page regarding the reliability of spraying MeOH.
Certainly the proposed use of the car makes a big difference, and I think we'll agree that it's always dependent on the tune.
EllowViper
Enthusiast
Its not like the ROEs are pumping 20-30 PSI of boost where outlet temps are really excessive. Even at the 13 PSI I'm pumping out (upper limit of the system), that equates to an additional 130 degrees of IAT above normal intake temps...so say in the range of 200-300 degrees respectively. I have no idea what the actual IAT is after my big shot of W/M...would be good to have that instrumented by someone just to have that knowledge. Even still, it will never be below 130 degrees due to the fact that the W/M is injected prior to the blower. I know some that spray after their turbos or centrifical blowers are getting at or below ambient IAT...which is simply outstanding!
steelskeet
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The title is misleading.It's not the cream-puff going "pop" - it's your "pushing the limits" that went down the gutter.
The Viper engines are terrible reliable - under normal operation - plenty of +100.000 miles cars out there
I think your reply is unintelligent and you are mistaken. The set-up I had has worked for countless viper owners for years. Mine worked fantastic for 2 years and was never pushing any limits. My W/M injection happened to fail resulting in detonation. I believe the same would happen if an intercooler failed. It seems that it is a weak link and that's why I am here figuring out what others have done.
You can keep your terribly reliable 100k mile viper and you can drive it "under normal operation" all you want... I want mine boosted and I will learn how to make it reliable
ViperGTS
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Have fun rebuilding your b(.)(.)sted cream-puff - I will in the meantime
in the meantime Mr Hemi Head
Enthusiast
The early Roe SC/5lb pulley combination resulted in a safe 100-110hp increase, using the cards supplied. Roe intoduced the w/m kit about 2 years later with the claim that a 6 lb pulley will work with creampuff motors. With the added boost, a bump in timing and w/m another 20-30hp could be expected but Roe did not claim any hp increase using this setup.
The early Roe S/C and a first production run w/m kit are on my car and both have always worked as advertised.
Your tuner knows his stuff but he has no control over fuel octane and w/m mix. The VEC does not have knock sensors and a car with a modified exhaust is too loud to detect detonation from the drivers seat.
With a 6lb pulley a safe w/m tune is in the 550hp range. More is pushing the limits and requires that the air temp, fuel octane and w/m mix is same as the day the car was tuned.
The early Roe S/C and a first production run w/m kit are on my car and both have always worked as advertised.
Your tuner knows his stuff but he has no control over fuel octane and w/m mix. The VEC does not have knock sensors and a car with a modified exhaust is too loud to detect detonation from the drivers seat.
With a 6lb pulley a safe w/m tune is in the 550hp range. More is pushing the limits and requires that the air temp, fuel octane and w/m mix is same as the day the car was tuned.
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Not necessarily true. You can definitely hear detonation, if you are paying attention.
EllowViper
Enthusiast
The audible detonation is pretty easy to hear even with loud motors and ambient noise. But from what I gather the inaudible detonation (on-set of detonation) can be destructive enough on the creampuffs to bust the ring lands well before you physically hear it. When I busted my creampuff, I was (knowingly) walking on eggshells tuning to the edge of audible detonation. Obviously (duh...) not the preferred way to do it and it bit me on a cooler than usual morning. With the forged, you can tune to the edge a bit easier and then pull the timing back as needed. When I was tuning for W/M, I'd tune just to the edge of audible detonation on low boost (~2 PSI) and then let the W/M hit. It is remarkable how the W/M quenches any indications of detonation immediately. Right now at ~13 PSI with W/M, I'm only pulling about 9 degrees of timing from stock.
speedracervr4
Enthusiast
Mr. Hemi Head, you've had some pretty nice cars in your past!!
EllowViper, have you dynoed your car with the 2.8 on it? You feel it's worth switching my 2.4 to a 2.8? Sorry for the thread hijack.
EllowViper, have you dynoed your car with the 2.8 on it? You feel it's worth switching my 2.4 to a 2.8? Sorry for the thread hijack.
EllowViper
Enthusiast
I would only switch to the bigger blower if you are desiring to get into the 10+ PSI range. And in all honesty, the 2.8 is still too small for the 488 motor since to get 13~PSI, I'm running the smallest pulley available (2.5 in) and spinning it to its max RPM. Belt wear is noticibly more due to the stretch and forces involved in spinning the 2.8 that fast. Haven't popped a belt yet, but I'm watching it like a hawk. As far as the dyno thing...not yet. Once more thing, installing the hotter cam made a HUGE difference. Slow speed drivability suffers, but WOT is just amazing.
speedracervr4
Enthusiast
Thanks for the info. I'm gonna be installing my Greg Good heads/cam soon and was woundering if the 2.8 was worth it. I think I'm going to stick with the 2.4 and my 10lb pulley.
EllowViper
Enthusiast
Definately send the $$ on the heads/cam and not the 2.8 upgrade. Love the 2.8, but you will realize more gains from the heads/cam.
Do you mind letting me konw how much the GG heads/cam set you back? I might be in the market.
Ellow: I noticed you said the low speed drivability suffered with your cam. I thought blower cams had more lobe separation (less overlap) than lopey N/A cams and many times the blower cams were smooth. Not the case with you?
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costanZo
Enthusiast
I would also like to know this for future reference.. As I am keeping my car N/A and doing pretty much just about every other mod I can do performance wise this summer... besides new heads/cam.
So pricing on the GG heads/cam or any aggressive heads/cam setup would be very appreciated.. thanks!
EllowViper
Enthusiast
Well, I went with with what GG recommended for the most part given the limitations with the stock valves (can't get more than .600 total lift on stock valves)...114 LSA with moderate lift on the intake (.575), more lift on the exhaust (.598), and longer duration. I think my biggest issue is with the solid roller set-up. It does not allow as much dwell between open/closing since there is less "slack" to take up in the valve train. When it warms-up, I'm running about .014 lash. Cold its .002 so you can see how the cam dynamics change with hot vs. cold operations. Now I have to say the engine really rev's a lot free-er and faster but there is a trade-off in some drivability. The aluminum flywheel might also impact the bucking and surging as well. I never had any with the stock cam/hydralic lifters. And finally, throw the issue of not having the right tune into the equation and you can see how I might have some low speed drivability issue. A good SCT tune would probably eliminate a lot of my closed-loop drivability issues.
The lower vacuum and the pcm forcing the idle to stay at the oem rpm would kill the idle transition. By merely raising the idle rpm with the SCT would help by itself.
EllowViper
Enthusiast
Absolutely Jack. I know during cold start, the stock PCM tune transitions from start enrichment into closed loop way to fast forcing my idle to drop before the "cam" is warmed-up. What I need is about 1500 RPM until engine temp is 140+ and then drop idle to around 850. I can pull about 15 inches of vacuum at 1500 and when warm at idle, I'm right at 10. COld start idle is terrible and the ROE bypass is fluttering on/off since vacuum is under 5 inches.
I am in process of putting in a cam with a very similar LSA, accept it has a .600 lift and is a bit asymmetrical.
