Hi guys, as the subject says I'm planning on building an engine. My car's a 74 challenger, used to be my daily driver, kept it running myself mostly but things got a little tough over here (i live in Dominican Republic, ordering parts got real expensive) so i had to get a modern car.

Now things are looking up, sent the car to get some rust removed, fresh coat of paint and brand new interior and since it's not my everyday car anymore im gonna do an engine swap. Been reading a lot, i know my way around a car but it's my first time building an engine, found a lot of info and i have a pretty good idea of all the upgrades i'll have to make...only thing i dont know is if a gen 2 HEMI will fit.

Any imput would be greatly appreciated, i'll be posting the project in the project section tomorrow with pics.

A Hemi fit in a 70, and 71 E body, so it would fit in a 74

Yup, those early years came with a Hemi. Depends what engine came in that car as to what is needed to swap in a Hemi - big block, small block, or slant six.

Thought so, just making sure before ordering parts. Thanks for your help and i'll kepp you posted.

Do a lot more research before ordering. If your car is a 318, you can't just drop in a 426. You will need to swap the front suspension, k member, transmission, etc. if parts are hard to get for you, then I would stick to the same engine family. If it's a 318, build a 360 stroked to 408. It will be a direct swap. Were there even any big block e-bodies in 74? If yours is a big block, then you have a lot of the parts needed for a hemi but be ready for sticker shock. A 400 can make a really stout stroker too for 1/4 the price

If ordering regular parts gets expensive, you'll fall over when you see hemi prices! Seriously, best of luck, your Hemi Challenger will be awesome!

Some things to consider, if your car is a factory V8 car, you'll probably need the conversion motor mounts from engine-swaps.com if yours is a slant 6 car, I think you need a V8 k-frame to even get started.

Also, if your car is a factory slant 6 or small block car you will need a different transmission and a new rear differential will be on your to-do list as well.

OP's 74 Challenger came with one of two engines. 318 or 360. Slants and big blocks weren't offered.

This is correct.

That's what I thought but couldn't remember for sure.

Building a Hemi can be one of the most frustrating and rewarding tasks you can do in the Mopar world. I've built one. Will never do another. There are many people here on the board that can help. Some hang out over in the race forum more, so post engine questions there.

Some things to consider: Cost. A hemi will be on the upper end of the spectrum. Once the part description has Hemi in it, the costs is 2-3x. You can use original parts, which you will be competing with restoration guys for which drive costs up, or use aftermarket, which don't always fit and may need some attention to work right. So you may get a bit lower cost, but added frustration. In either case, some parts are pretty scarce and will put a substantial dent in your bank account. Second: overall drive train. If your car had an 8 cylinder, there are conversion mounts that allow Hemi to bolt in. TTi headers will clear everything. They cost, but fit. Clutch/trans will be an issue if you are building big power (and why not if you are already building a Hemi). You will need a McLeod street twin and preferably a Hemi 4spd (18 spline). A 23 spline may hold up, they are pretty robust to around 450 to 500 ft-lbf torque from what I have read. Maybe that is optimistic though. Rear end will be an issue too if you don't have at least a decently built 8-3/4. A more stock build Hemi would probably work fine in front of a 23 spline trans and 8-3/4" rear with street tires. The tires will be the "fuse" in the system that will break away first.

If you can handle that, then I say go for it. Otherwise, a decent wedge with a stroker can build almost as much power for less cost. You will still have drive line concerns though, as a decent 440 with a 499 stroker kit and aftermarket heads can get 600 hp. You will still need a v-8 k-frame too.

Good luck.

welcome to the board a gen 2 hemi is pricey like most have said if your dead set on having a hemi may i suggest going gen3 hemi? there is plenty of motors out there and the swap can be done for half of a gen2 the nice thing about the gen 3 is you can daily drive if you wish and not worry about performance vs mpg

As stated above ,Hemi =$$$$$$ lots of them. I'm putting one togeather ,been about 4 years of buying expensive parts. After spending about $10,000 and being nowhere close I thought WHAT THE HELL WAS I THINKING>

I'm building a 426 Street Hemiroid motor for a local customer for his 1970 Challenger, the motor is being built with mostly new parts, new World 4.490 rough bore block, used older KB top fuel 4.500 stroke crank, a set of lightly used Manley steel I beam SS rods, new custom made Diamond pistons, new Stage V heads, used Stage V cast aluminum valve covers that will be polished, all new Stage V rocker gear, new custom made Manton pushrods, new polished 2x4 inline Stage V intake manifold set up for EFI with dual 4150 dry throttle bodies, solid roller cam and lifters, seven quart Milidon road racing oil pan and probably a Milidon external oiling system.
Any hemi motor, Gen 1, Gen 2 or the new Gen 3 will not be cheap or easy to build to get good results, hence my Hemiriod name for them pain in the rear motors
I've been racing and building the Gen 1 Chrysler Firepower Hemi and Gen 2 Mopar 426 street hemi motors for a long time,(started in 1965 on my first 1955 Chrysler 331 motor) no experience yet on the new Gen 3 motors, yet
EDITED : Buying any parts for the 426 hemi will be expensive and their are currently no new cast iron blocks being made so plan on buying a new aluminum block or wait for a new cast iron block to be made or look on the internet trying to buy all the used or new parts needed to build your motor
Hemi motors are impressive and they can be made to make a lot of power, but not cheaply or easily
Think long and hard before choosing, just like marriage
Good luck regardless on what you choose to build

Cab
Let me know when you're ready for the EFI. If you have my book, you saw one of my early dual throttle body EFI 572 HEMIs. Lots of changes since then.

Rich

Rich, I have your book . How can we find out the latest changes in EFI

Yes, consider other engines (highly recommended).

A well thought out 360 or 318 stroker will put the car in the 12's easy and be very streetable. Far less expensive. My Challenger runs stock ported heads, dual plane intake, headers, 224@.050 cam. With a 3.55 gear its been 12.70. Also important it runs on 86 octane.
Doug

I have your book - good stuff!

So, is there an updated or new book in the works?

Maybe a book on some basic/fundamental EFI tuning?

Thanks!

I considered a book on EFI, but I decided that the rapid changes in electronics and software development would mean the book would have a short pertinent life. The basics would hold because the physics of a 4-stroke engine don't change, but a reader would probably want some specifics about products that are currently in the market and how they are different. That could be a series for a magazine.

But I am considering something online that would be available through my web site. There I could cover the EFI basics that are product independent and then let the reader take whatever path he wants depending on the product that's of interest.

Then I could follow up with an online training course for the specific products I support. I would charge a fee for each course. I have written interactive correspondence courses before and they can work very well if the reader can download work books, quizzes and can track their progress.

Or maybe I'll just go fishing!

Ding ding ding I (do) believe we have a winna.