Hope they offer something for those who allready have HEADS ie. intake package ?
Gen-4 intakes are not compatible with previous generation heads.
800HP V10 crate engine, 650HP bolt-on kit for Gen III's, announced today
- Thread starter srt4evah
- Start date
Gen-4 intakes are not compatible with previous generation heads.
JAY
Enthusiast
Gen 4 Heads obviousely . Intake package would be niiiice !
That part of the equation itself is easy...?
Just don't forget those heads wont bolt right on
FastMatt
Enthusiast
I'm still kind of lost as to how this set-up is going to make MORE hp then a stock gen 4????
Simple... they are selling a package with numbers based on modifications it doesn't include. LOL
But seriously, it could make those numbers if built correctly. IMHO however, they shouldn't be marketing it like they are. They are marketing it on price point rather than honesty. If ANY tuner did the same thing without a full and obvious disclosure, they would get REAMED. Mopar always seems to squeak by such criticism unfairly... but as many people know, I don't exactly cut anyone slack on those things, especially Mopar- they have the least excuses of anyone with their R&D budgets, inside info, and ease of implementing solutions.
Is it still a good price? YES. But they should not be marketing it like they are. Now we all have to fight the "stigma" this package is going to produce; "Well, Mopar can do it for less money! Its from Mopar so it should be complete!" WRONG. WRONG. WRONG. The only thing this is going to cause is Tuners sweeping up Mopar's mess on this one... and uneducated installers are going to get CRUCIFIED.
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FastMatt
Enthusiast
What will be very interesting will be how much power will it make with a big cam and headers (maby even porting the heads). Then we will know how much power a Gen 4 would make IF anybody ever cracks the ECU.
Has already been done in different forms:
-Gen-4 engines without Head Work work can make 740 Crank [Manifold Port/Headers/Exhaust/ACRX Computer/Minor Accessories]
-Gen-4 engines with Head Work can make 765 Crank [Mild Head Porting/Manifold Port/Headers/Exhaust/ACRX Computer/Minor Accessories]
-Gen-4 engines Without Head Work w/Big "Solid" Cam can make 800 Crank [Headers/Exhaust/JTEC Computer/"Solid" Camshaft/Accessory Delete]
The Gen-4 cam is a moderately aggressive camshaft, so the same numbers could be expected from a properly build Gen-3/Gen-4 package, if not better. Just from the standpoint of actual tunability on the JTEC controlled cars it should not be a hassle to beat those numbers, but you could also run a larger cam if you wanted and surely beat them. That is not to say that the Gen-4 is not still a superior platform overall when it is actually under your control, but a Gen-3 based conversion could certainly put out peak power numbers that would be higher, more easily than a true Gen-4 with its Venom Controller "Handicap".
-Pectel ECU's can control G4, so if someone really wanted the control, it IS available, but its not a cheap or easy task.
Now... what I personally want to see, is who is going to be the first person who steps up and has a Pectel installed in a Gen-3 with a G4 conversion, and has the car converted over to Electronic Throttle, adding in some of those extra... tidbits
As much as some people hate on ETC/DBW, it is better. Period. If you have a controller that offers it, you would be crazy not to use it. Don't hate the technology because Dodge botched the programming in the name of "smoothing it out"
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As Nader pointed out above, yes, the Mopar kit will fit under a G3 hood. The true G4 manifold is supposedly higher down the center. The intake manifold supplied in the Mopar kit is basically half G3, half G4. Which is why IMHO, it looks so goofy.
That being said, personally I am curious if a G4 manifold will actually fit under a G3 hood. I do not know anyone who has actually tried it, but I sure cannot see enough of a height difference between that Mopar manifold top and a true G4 top to make a difference. The airbox arrangement is certainly different, but I just don't see, from a simple perception standpoint, that the G4 manifold is nearly high enough to cause a problem here.
However, until I prove the "it wont fit" statement false, I will err on the side of caution and say you cannot fit the true G4 manifold under a G3 hood.
Regardless of the reasoning however, it is still true that the G4 hood and airbox system is an improvement over the G3 design, in any case.
mnc2886
Enthusiast
These horsepower estimates are a bit high. I may be wrong, but the highest rwhp SAE I saw on a gen IV was 630. That was with ported heads, intake, exhaust, bolts on, and mopar ecu. This may start some flame comments, but I am not a believer in the "% horsepower loss." Jut because you add more horsepower, doesn't mean the horsepower loss increases. If the drivetrain stays the same, so should the horsepower loss. For example, the stock gen IV viper dynos at 535-545 which suggests about a 60 hp drive train loss. That would mean probably a 690-700 HP at the crank is the best we have seen on a gen IV.
What this also leads me to believe is that ZR1 owners have been lied to. That car dynos at about 530 to the wheels. Every other corvette (z06) shows about a 55-60 horsepower drive train loss as well. We all have seen on some tv shows that a gen IV viper has pulled a little on a ZR1. I firmly believe that the ZR1 has 600 HP at the most, not the promised 638. I know the corvette comments are off topic, but I had to say it.
Check my profile... this is what I do
-Believe me, 630 to the wheels has been done without head work. 631 to be exact, and not on my dyno, in 80+ degree ambient. I built the engine. It is in Kevin Ferguson's ACRX, and took first place in USGT this year.
-655ish was just recently done by RSI, on a Gen-4 Street Car, with mild headwork and most of the same bells and whistles that are on Kevin's car.
-The 800 horsepower engine is THIS THREADS subject.
Using 15% standard drivetrain loss, the above numbers are dead on. And yes, horsepower loss is absolutely a percentage, not a set number. The faster you try and accelerate something, the more it will have intertial resistance of an increasing degree, and the more losses with regard to fluid viscosity will have an impact. Using a typical Gen-4 as an example, 535 RWHP, and figuring an average of 610 actual crank HP, you get a 13% drivetrain loss, right in the ballpark of the assumed numbers.
With regard to the ZO6, you are comparing an N/A engine to a Supercharged one. Somewhat different ballgame when factoring in ambient temps, fuels, and heat soak to name a few items, and as a result you will see results all over the map. It could also be that GM is not being conservative, while Dodge is. These 535-545 Vipers may actually be closer to 625 crank, not 600, while the Vette is dead nuts at 638 on a good day. The "big round number" of 600 should be an indicator... while GM was surely scratching for every horsepower that they could claim at the oddball 638.
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Greg Good Cylinder Heads
Enthusiast
Check my profile... this is what I do
-655ish was just recently done by RSI, on a Gen-4 Street Car, with mild headwork and most of the same bells and whistles that are on Kevin's car.
-/QUOTE]
It wasn't "mild", was my all out port job.
Check my profile... this is what I do
-655ish was just recently done by RSI, on a Gen-4 Street Car, with mild headwork and most of the same bells and whistles that are on Kevin's car.
It wasn't "mild", was my all out port job.
Got ya. Either way, they are impressive numbers coming out of these engines.
I will be checking this the first chance I get. I have a G3 hood laying around, and the hood is off my G4 based car currently... so I will give this a try and see what the real deal is. I really don't think fitment will be a problem with true G4 manifolds the closer I look at this. If it is, it is going to be some oddball location where something intersects unexpectedly.
Greg Good Cylinder Heads
Enthusiast
Yeah....the Gen 4's are real heads. Better exhaust port and better wet flow due to improved intake valve location. The Gen 3's aren't bad all-out ported either. My best N/A power is still a Gen 3 at 650 rw, but the 4 will eventually beat it.
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Now that I know that was more of an advanced job and what I would assume is a ported manifold as well, my personal feeling is that the G4 in question above [that you did the heads on] would probably benefit from additional manifold volume and throttle body size, and especially ECU control. Twin 85's on a manifold with 25% more volume, with those heads, a ported manifold, and a Pectel revving to 7000-7500 should SCREAM. The same would go for a G3/G4 conversion with the right cam and its equivalent parts.
Which raises the question... on a G3/G4 conversion, which will probably take the record due to Venom Controller "handicaps" on true G4, and the fact that larger T-bodies will be available for some G3/G4 conversions *wink* Twin Mechanical 76.5's *wink*, which column does that win go to? G3 or G4? haha.
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Greg Good Cylinder Heads
Enthusiast
I don't think the RSI Gen4 had a ported intake. I'll find out. There is a little more power there.
Gen 3 with Gen 4 heads have the most potential for now. But the Gen 3 still has more in it. I think one will hit 700 rw by spring. *wink*
Gen 3 with Gen 4 heads have the most potential for now. But the Gen 3 still has more in it. I think one will hit 700 rw by spring. *wink*
JAY
Enthusiast
This is a great post , with even greater knowledgable info ! Thanx for sharing and helping those like myself make a good decision !
mnc2886
Enthusiast
Check my profile... this is what I do
-Believe me, 630 to the wheels has been done without head work. 631 to be exact, and not on my dyno, in 80+ degree ambient. I built the engine. It is in Kevin Ferguson's ACRX, and took first place in USGT this year.
-655ish was just recently done by RSI, on a Gen-4 Street Car, with mild headwork and most of the same bells and whistles that are on Kevin's car.
-The 800 horsepower engine is THIS THREADS subject.
Using 15% standard drivetrain loss, the above numbers are dead on. And yes, horsepower loss is absolutely a percentage, not a set number. The faster you try and accelerate something, the more it will have intertial resistance of an increasing degree, and the more losses with regard to fluid viscosity will have an impact. Using a typical Gen-4 as an example, 535 RWHP, and figuring an average of 610 actual crank HP, you get a 13% drivetrain loss, right in the ballpark of the assumed numbers.
With regard to the ZO6, you are comparing an N/A engine to a Supercharged one. Somewhat different ballgame when factoring in ambient temps, fuels, and heat soak to name a few items, and as a result you will see results all over the map. It could also be that GM is not being conservative, while Dodge is. These 535-545 Vipers may actually be closer to 625 crank, not 600, while the Vette is dead nuts at 638 on a good day. The "big round number" of 600 should be an indicator... while GM was surely scratching for every horsepower that they could claim at the oddball 638.
You make some good points and I appreciate the discussion. I didn't know we had gen IVs dyno that high. As far as frictional losses, (again, I may be wrong) it seems an increase in torque would result in less horsepower loss because you have more initial force against friction. I also understand the environmental effects on a supercharged engine, but I still don't think a ZR1 makes the horsepower it claims.
ROCKET62
Has Left the Room!
Interesting point - should driveline loss be measured as a percentage - or is the driveline loss constant for a given setup? Does driveline loss really increase as HP/TRQ increase?
JAY
Enthusiast
When talking to one of the main SRT engineers , they mentioned losses to be 12% to 13 % , for drive line losses . Hope this helps 
mnc2886
Enthusiast
When talking to one of the main SRT engineers , they mentioned losses to be 12% to 13 % , for drive line losses . Hope this helps
All that is though is a calculation. What I believe is that horsepower losses shouldn't increase as horsepower increases.
On Gen 4 engines we see 605-610rwhp with ported heads, ported manifold, headers, Mopar controller and modified air inlet (we have done 15 cars). On our Gen 4 track cars with forged pistons and a differing intake centerline, 630rwp has been seen. We use a Dynojet for our power numbers, we also have a Dynapack Dyno as well, that reads about 10% higher. Keeping the VVT and changing to a standalone EMS (there are currently 4 available that can control DBW) more power could be seen.
We have tested and Modified ZR1 Corvettes and found that they baseline about 530rwhp on our Dynojet. Our modified ZR1's make the same power as our modified Gen 4's (non-supercharged).
Hope this information adds some info to what has been relayed.
We have tested and Modified ZR1 Corvettes and found that they baseline about 530rwhp on our Dynojet. Our modified ZR1's make the same power as our modified Gen 4's (non-supercharged).
Hope this information adds some info to what has been relayed.
I am sorry, but this is just not a correct thought process. While I can understand how you are coming to the conclusion, and it makes sense on the surface, you aren't taking into account that as torque output increases, so does frictional forces between gear teeth, bearings and races, losses due to deflection of components, higher horsepower often occurs at increased RPM/relative fluid viscosity, etc. While we all like to think of "horsepower" as a simple function of Torque x RPM, the truth is that inertial forces have a great deal of influence on how it is measured and calculated, and the same goes for the polar moment of the components in the drivetrain itself.
Our standard method of calculating horsepower is by spinning up a drum, calculating the time and rate of increase, and mathematically working backwards. The problem is, this method relies on rate of change, and is not a direct instantaneous type of measurement. This is one of the reasons that different calculation methods have different outputs. One of the more direct versions, such as a strain gauge on a critical drivetrain component that can directly measure applied torque, would give a better instantaneous torque and horsepower measurement, and would not be as greatly affected by these things. However, when standard measurement systems apply, a percentage is the correct general method, as the "error" will increase as the horsepower increases, and there is no way around that. So far as ACTUAL losses, yes, they will STILL increase as horsepower increases, however not at a linear rate.
No matter what, a percentage is the standard method, and EVERY system will differ, with each slightly different variation of each system being a whole other ball game. Chassis/engine calculations are nowhere near an exact science, but in general we all assume that Viper's are similar enough to utilize these comparisons efficiently.
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351carlo
Enthusiast
Fantastic reply. Spot on accurate and very informative for those who were unaware.
KenH
Enthusiast
I was told that during the VCA presidents meeting when they toured the as-of-then then unreleased Gen IV engine dyno area, the engine they were dyno'ing at the time was putting down 624hp which would jive with Dan's numbers above.
mnc2886
Enthusiast
Very well put. I am absolutely following now.
