Gen 3 Hemi Swap time!!!

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SRT_DSTRHOLC

SRT_DSTRHOLC

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So I need some help from the guys who have done this. I know that things are very different from when the Gen 3 was first introduced. I have people telling that they are using Car and Truck engines. I want to know what experience you guys have. Im looking at a 09 and up 5.7. I see no point in getting any bigger engine with my purpose of going twin turbo or Procharger.

I will also need info from those that have used the new Hemi MegaSquirt plug and play box please!

Also any other little facts help, I am using a aftermarket K frame too and staying with my 904
 
Your main issue with the 09+ engines will be the VVT. I think the aftermarket control systems have gotten better, but it can cause more headaches than it's worth. Really the main difference between the new and old engines is the heads and VVT. You're only talking ~40 hp difference between the two, which is pretty easy to make up with a few upgrade on an older engine, but new ones might be more available in junkyards too.
 
A modern '09 & up Hemi with a 904? Are you going to keep the soft suspension, flexible chassis and 9" drum brakes to match that 904? Forgive for the sarcasm, but why no overdrive?
 
Map63Vette said:
Your main issue with the 09+ engines will be the VVT. I think the aftermarket control systems have gotten better, but it can cause more headaches than it's worth. Really the main difference between the new and old engines is the heads and VVT. You're only talking ~40 hp difference between the two, which is pretty easy to make up with a few upgrade on an older engine, but new ones might be more available in junkyards too.
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Main issue now isn't the VVT. New systems allow you to run it, but this doesn't apply to me because I won't be running it with a twin turbo and aftermarket camshaft. Automatic has MDS, which requires you block the MDS off. I will not be using any of it.
 
jbc426 said:
A modern '09 & up Hemi with a 904? Are you going to keep the soft suspension, flexible chassis and 9" drum brakes to match that 904? Forgive for the sarcasm, but why no overdrive?
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You are more than welcome to cut my floor up and patch it back up if you would like to do the work.


I don't need the extra pain in my life, I main decide to go a different route later, but at the moment I have a 1500 dollar transmission and converter....That I will be using.

Below are my options for Auto:
Automatics:

904 or 727 both can easily built to handle the torque and HP of a Hemi. No modifications to floor pan. Though you do need to shim the trans .060 as the modern Hemi has a different off-set. Bouchillon Performance and many others sell the spacer. Otherwise it is a direct bolt up.

A518 has an overdrive and as others have pointed out requires floor surgery, though not nearly as much as a RFE545. Does NOT require a computer. Can easily be built to handle the torque/HP of a modern Hemi. Like the 727/904 you should shim trans.

RFE 545 Stock Hemi trans. The truck/SUV trans has the speed sensors built into the trans so it is the easiest to retrofit into a muscle car. Hot-Wire can build you a wiring harness to use the truck transmission behind your hemi. Benefits a five speed with two overdrives. Requires SIGNIFICANT tunnel surgery, along with a custom cross member.


The RFE 545 is a weak link and requires a lot of work. I would do the work...but is a weak link for my power. The 518 would be the only other choice from a 904. So if you read the original post, and saw my possible decisions for power making, you would know why I am doing 904.


There is always gear vendors too.
 
Might be getting help from a custom shop in Canada. They are HPI Customs and possibly even American Powertrain. I might be going T-56 Transmission after all for pro-touring needs and overdrive factor.
 
I think you might be better off with the early 5.7's as opposed to the VVT motors. You can throw a set of Eagle or Apache heads on top, and have the ability to choose from a wide variety of cams whereas the VVT motors are fairly limited in cam choice (and extremely spendy). Initial cost of entry for the older 5.7's will be lower as well. If you dont plan on using any of the new tech, why pay for it?

When I got my truck running this spring I was holding out for the EFI Source plug and play for VVT. After months of excuses and failed timelines I finally gave up waiting. I have not seen any new confirmation that they are actually shipping them. I dont know of any other megasquirts that were VVT capable. One more reason to go non VVT.
 
cu440da said:
I think you might be better off with the early 5.7's as opposed to the VVT motors. You can throw a set of Eagle or Apache heads on top, and have the ability to choose from a wide variety of cams whereas the VVT motors are fairly limited in cam choice (and extremely spendy). Initial cost of entry for the older 5.7's will be lower as well. If you dont plan on using any of the new tech, why pay for it?

When I got my truck running this spring I was holding out for the EFI Source plug and play for VVT. After months of excuses and failed timelines I finally gave up waiting. I have not seen any new confirmation that they are actually shipping them. I dont know of any other megasquirts that were VVT capable. One more reason to go non VVT.
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Base engine makes more power. Will be running as is then building side block to swap heads on. I will see what Modern Muscle suggest, if they say do this, than I will do this. But eagle heads sell for around 1200 and I can get an entire 09 and up for 2k
 
If you don't like the idea of a spacer in between the 904 and the motor, ATI makes a flex plate with the .060 offset built in so that your 904 can just bolt up to the motor.
part #915685 I believe.....
 
RockinRobin said:
If you don't like the idea of a spacer in between the 904 and the motor, ATI makes a flex plate with the .060 offset built in so that your 904 can just bolt up to the motor.
part #915685 I believe.....
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Thank You, that helps greatly. That plan is to use the 904, but I may have something in the works to go T-56 6 speed.
 
unlike a lot of people on here who are giving advice,(some good. some not)
i have a finished and running turbo g3 in my 68 barracuda using the megasquirt. after reading some of your replies, it sounds to me like you have it all figured out. these guys are taking their time to try to help you out,and all you are doing for the most part is trying to prove you know more than them....if you know what you are doing, dont ask advice on what you should do!!!!
 
mcat said:
unlike a lot of people on here who are giving advice,(some good. some not)
i have a finished and running turbo g3 in my 68 barracuda using the megasquirt. after reading some of your replies, it sounds to me like you have it all figured out. these guys are taking their time to try to help you out,and all you are doing for the most part is trying to prove you know more than them....if you know what you are doing, dont ask advice on what you should do!!!!
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Well I believe you're right on the part that I know what I am doing, but I should have clarified more on the type of help I wanted. I'm looking for the type of help, when needed, that helps me when I have issues or better ways of doing something. Like now I'm thinking about an earlier 5.7 and just building that because with aftermarket cams, the vvti gets shut off anyways. I don't mean to sound condacending, I just want advice thrown in when needed. If I already have plans, give me advice for the plans I have. I wanted the 09 engine because it already comes with the heads I want and makes more base power for a engine to start with. That way when I have something to drive while I save for the turbos.

Also the questions I asked were about car or truck engine, found out I can use either. Next question is for those that have the megasquirt gold box, I want to know info like where I can find tuning info etc
 
here it what i know to be facts.. from experience.
unless you have a chassis car or your car weighs 4500lbs+ a properly tunes completely stock 5.7 will generate more power than will be used with around 12lbs of boost. so without a full cage and cert. you dont need big cubes and high boost numbers.
boost is boost regardless how you get it , single or twin...10psi is 10psi.
the flow difference of early and eagle heads mean nothing under boost. so, if you are just chasing dyno numbers, that doesnt matter either because no one will believe you either way..(fact)at the weight im at and the power i put on a dyno, there is no reason very low 10 sec passes cant be reached. but i have a street car with no cage, so i have to slow my car way down.. i have a completely stock 06-5.7 shortbock with stock 6.1 heads and 6.1 cam and intake.
 
You've overlooked a well built 200R4. Holds over 1000hp, requires only the notching of the torsion crossmember and bolts right up to the new Hemi's. It's also available with a lock-up converter that is controlled with one 12v wire. It also is much more efficient of a design than the Mopar overdrives, and takes less power to spin.

Either way you go, it sounds like it will be a fun car.
 
mcat said:
here it what i know to be facts.. from experience.
unless you have a chassis car or your car weighs 4500lbs+ a properly tunes completely stock 5.7 will generate more power than will be used with around 12lbs of boost. so without a full cage and cert. you dont need big cubes and high boost numbers.
boost is boost regardless how you get it , single or twin...10psi is 10psi.
the flow difference of early and eagle heads mean nothing under boost. so, if you are just chasing dyno numbers, that doesnt matter either because no one will believe you either way..(fact)at the weight im at and the power i put on a dyno, there is no reason very low 10 sec passes cant be reached. but i have a street car with no cage, so i have to slow my car way down.. i have a completely stock 06-5.7 shortbock with stock 6.1 heads and 6.1 cam and intake.
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Car is getting 10 point cage and certified. I don't plan on running high boost either, twins is for the ability to make more power when wanted. I understand that boost will make any engine more powerful, so I appreciate the info. And especially Giving me an insight to your build. I'm going to message you to find out more about it too!
 
Engine choice is on hold. Those that have posted about getting an earlier NON MDS or VVT year engine are being listened to. I am considering all years of semis now. But, I may be starting with a 6.4 now. An aftermarket stroker kit for a 5.7 is around 1900, so that plus a core engine for around 1000 puts me at 3000. I have been seeing 6.4s go for around 4k-5k. They do have MDS, but it can be locked out if needed. However, the 6.4s come with the best flowing head from factory, known as the Apache head. This is the closest engine besides the eagle 5.7 to an LS engine. This head flows in the mid 300s from factory. The engine also like the 6.1 comes factory with a forged crank good enough for any power you want and it helps because there is a company that sells matching factory weight forged pistons and rods that drop in with no balance needed to fortify the bottom end for boost.


But, in the end I am willing to look at any engine for the right price. Complete engine or block only
 
as to core motors i buy the early 5.7s for around 250-300 and thats fairly complete intake to oil pan and front cover.
 
wish i still did. had 4 last summer sold 2 and the 2 i still have i plan on building for my own cars. i watch craigs list everyday for them to show up. but i also keep an eye on the whole state and Portland since i'm only 2 hours from it. most guys ask around 400-500 but they don't sell very fast and after a couple weeks they become willing to go down in price. the first one i bought i did pay 800 for but it was complete out of a 2004 dodge ram. suppose to have ran but the truck got totaled. came with all front drive pieces, the computer, intake, and exhaust.
 
RockinRobin said:
If you don't like the idea of a spacer in between the 904 and the motor, ATI makes a flex plate with the .060 offset built in so that your 904 can just bolt up to the motor.
part #915685 I believe.....
Click to expand...

The shim is not a 'must' - plenty dont run it or need it.
 
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