Gen III to Gen IV Engine Build
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mxz900
Viper Owner
Re: Gen III to Gen IV Engine Build
Originally Posted by Bobpantax
How does the cost of doing what you are doing compare to the cost of buying a new Gen IV engine and puting it in your car?
CONSIDERABLE difference. Easily an extra 5-8K in parts, not including the computer or wiring. You would either have to go aftermarket at 10K+, or you would have to completely revise the engine wiring harness and controller system, basically building your own, as the Gen-3 and 4 harnesses share almost no similarity. You would have to update the bus system, the pedal system, and integrate the newer Occupant Restraint System to keep the new bus system happy- meaning you have to buy an engine harness, VENOM, Bus modules, ORC, Pedal system, and then integrate them. HUGE mess overall- easier to just sell and buy a G4.
The only time a FULL G4 conversion makes sense, is if you were going TT or extreme track duty, needed an engine anyway, and could easily justify the aftermarket controller cost as you would truly be "using it"- then its a real option to make the changeover. Going aftermarket allows you to keep the JTEC for Bus use, which is a better solution than even Aftermarket + Venom, as it is easier to keep the JTEC quiet than a VENOM.
If you get a gen 4 engine and trans with the computer and wiring harness what else would need to be converted to get the engine to work? I saw a post that a gen 4 hood is required for the larger intake clearance. Will the stock gen 4 headers fit right into the gen 3 exhaust? JTEC? Bus? Controller? Pedal System? What exactly are each of these items?
I am basically sitting with a blown gen 3 motor that needs a crank and internals. Heads are good, but will need to do the oil pan conversion for track duty anyways and cost wise not sure it doesn't make more sense to just throw a used gen 4 and trans in, get a hood and whatever else and be done. Question is what does "whatever else" include?
Originally Posted by Bobpantax
How does the cost of doing what you are doing compare to the cost of buying a new Gen IV engine and puting it in your car?
CONSIDERABLE difference. Easily an extra 5-8K in parts, not including the computer or wiring. You would either have to go aftermarket at 10K+, or you would have to completely revise the engine wiring harness and controller system, basically building your own, as the Gen-3 and 4 harnesses share almost no similarity. You would have to update the bus system, the pedal system, and integrate the newer Occupant Restraint System to keep the new bus system happy- meaning you have to buy an engine harness, VENOM, Bus modules, ORC, Pedal system, and then integrate them. HUGE mess overall- easier to just sell and buy a G4.
The only time a FULL G4 conversion makes sense, is if you were going TT or extreme track duty, needed an engine anyway, and could easily justify the aftermarket controller cost as you would truly be "using it"- then its a real option to make the changeover. Going aftermarket allows you to keep the JTEC for Bus use, which is a better solution than even Aftermarket + Venom, as it is easier to keep the JTEC quiet than a VENOM.
If you get a gen 4 engine and trans with the computer and wiring harness what else would need to be converted to get the engine to work? I saw a post that a gen 4 hood is required for the larger intake clearance. Will the stock gen 4 headers fit right into the gen 3 exhaust? JTEC? Bus? Controller? Pedal System? What exactly are each of these items?
I am basically sitting with a blown gen 3 motor that needs a crank and internals. Heads are good, but will need to do the oil pan conversion for track duty anyways and cost wise not sure it doesn't make more sense to just throw a used gen 4 and trans in, get a hood and whatever else and be done. Question is what does "whatever else" include?
Please don't take this the wrong way, but if you are even entertaining the idea of trying to run a Gen-4 engine in a Gen-3 and are asking questions about bus systems, pedals, and controller... you are in way, way, way over your head on that type of a project. There are too many electrical differences between the two generations to be even remotely close to worthwhile to do a true conversion when talking about using an OEM wiring harness design and controller system- you would be thousands and thousands of dollars into tracking down every conceivable electrical change and compatibility issue in the car. This is NOT plug and play by any ridiculous stretch of the imagination. The only way to circumvent such problems is the even more ungodly costs of going to completely aftermarket Engine Management System, which would still require near complete engine wiring harness design and production.
You are talking OEM level engineering and design problems here, something that even most professional tuners would not touch with a 10-ft pole. The engine in Gen-3's and 4's is not a standalone system, it is integrated with the chassis wiring harness and many other modules over a databus. Gen-3 and Gen-4 cars are fundamentally different in this regard, as the Gen-3 is a PCI based system, where the Gen-4 is a PCI/CAN hybrid arrangement. The problem is that you cannot simply add the hybrid engine system into a Gen-3, you have to replace and re-wire every single other unrelated module that is designed to work with that hybrid system. The aftermarket controllers can get around this as they effectively control the powertrain without needing to communicate with other modules, and in fact the JTEC is a better platform from which to do this than the VENOM as it is less invasive, but it is extremely expensive. You would barely even have your foot in the door on that option at $10K.
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TowDawg
Enthusiast
The build looks great! It's just too bad you're gonna burn up the valves trying to run that Gen III fuel pump!
The build looks great! It's just too bad you're gonna burn up the valves trying to run that Gen III fuel pump!
True Story... the Wideband told me it was safe, but what does it know.
The thing is a liar anyway. I caught it cheating on me with a Spark Plug the other night....
mxz900
Viper Owner
Thanks for the info Final GTS on the gen3 to gen4 swap. That is what I wanted to know. This is definitely not something I am looking at doing myself as I am not a mechanic. Was just curious if it was worth entertaining the idea. If it was roughly close to cost to rebuild my gen 3 motor I would much rather spend a little more to have the gen 4 engine.
Quite like this one... no. There are some other more basic conversions out there however.
That said, a Gen-2 version like this will be coming soon
Guys considering selling this car. Aside from this engine build it has the best of everything. 26,000 miles. New to car and these pics are 18 -19 black HRE setup with new sport cups. Serious inquiries please PM me.
Figured I would revive my thread regarding my NA Build. To this day not a single issue and the car is an animal. Since the build i put sport cups on it. Now power is more useable. Thanks again Dan for something truly unique and a piece of Art.
This car will soon have a few siblings
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Thank you again Tom, it is still one of my favorite builds to date!
This kind of a result is what we go for. It is not just about how much power a build makes or how it looks; it is about the whole package. If it doesn't drive well, have bulletproof reliability, and require virtually no maintenance and upkeep, it is not the kind of package we are looking to create. Our builds go YEARS without any service other than Oil Changes, and have no issues and hassles in between.
This kind of a result is what we go for. It is not just about how much power a build makes or how it looks; it is about the whole package. If it doesn't drive well, have bulletproof reliability, and require virtually no maintenance and upkeep, it is not the kind of package we are looking to create. Our builds go YEARS without any service other than Oil Changes, and have no issues and hassles in between.
