Gen III Hemi swap help.

[darten1972]

Hi all. My 72 Swinger currently has a 318 with 1.88 360 heads, purple shaft 340 cam, Dougs Long Tube Headers and a Air Gap intake. Motor works great but I'm looking for more power. I love the idea of a 408 stroker but they appear to be very costly. I can get my hands on a Low Mile 2006 Gen3 5.7 Hemi for a very reasonable price and considered doing something with it but I'm just not sure. I'm looking for approx a 400hp motor. Ideas? Thoughts. What do you guys think? Thanks for your input.

 

[Johnny Mac]

Hemi's are awesome, but if you've found that 408's are "too costly" then a newer hemi is not your answer my friend.

You'll have far more $ in the electronics and other accomodations on a Gen III than you will in a 400 HP SB complete long block. This hemi would need to be free to even be on the same table as just swapping in a reasonable 408. I have done both, sell both, and I'd check out the 408 below. These dyno right under 400HP, and your WP, Distributor, and carb will transfer right over.

BPC4082CT - Blueprint Chrysler 408 Base Engine • Iron Heads • Flat Tappet Cam • Base • 375 / 460 FT LBS

If you have to have a 3g hemi, again you're looking at some big unforeseen dollars in exhaust, electronics, engine mounts, flexplate, making you kickdown work ETC. We can have that conversation also...just trying to help you watch your dollars right off the rip. all this 408 is missing is an intake manifold, if using all your 318 changeover parts.

 

[rod7515]

I did some checking 2 weeks ago because I was thinking about doing a modern hemi swap on a car but found that the electronics, trans fitment would cost way more then i ever expected. Do a google search on hemi swap and you will find lots of info and pricing for different options. Best of luck
Rod

 

[Map63Vette]

It's tricky. 400 hp out of a modern Hemi is basically a camshaft away, maybe some headers as well. However, as others have stated, putting the engine in the car is where the costs will get you in that case. It's not terrible and can be done reasonably cheap depending on what you are willing to put up with. I had mine running in my car, engine included for right around $5000. What you have to start with can make a big difference too though. I got another K member, swapped to manual steering, and bought headers. Also started with a carb, but if you're handy you can use the factory injection and cut up a harness. I didn't get one with my engine, so I had to go a different route.

 

[kb67mopar]

I priced out getting to right around 450 hp. a 5.7 in running condition ranges from 800 to 2000 bucks depending on source and miles. the cam swap will run you around 800-1000 depending on parts sourcing and that is for cam, lifters, springs, retainers and push rods.

Engine installation costs to the car depends a lot on you and your wishes/skills. Motor mounts are around $200 total if you use conversion mounts from TTI and replace the isolators with new. Exhaust you can fabricate pretty cheap on your own or pay TTI a lot of money. Headers...TTI is about it for a conversion swap or again, build your own. Oil pan is $375 ish between pickup tube and pan. Then plan on the electronics to make it run...$1200 for hotwire auto or $1400 for megasquirt or other combos out there. IF you want to run CARB then you spend $4-800 on an intake and $800 for a MSD ignition control box. If running fuel injection you need to supply a fuel pump too, and the best method is putting in an in-tank pump. I'd retrofit this myself and save some cash but you can pay for kits too.

add it all up and you can probably stroke your small block to get the same power output...but personally I love fuel injection and the reliability that brings.