Engine swappers: I need engine advice for a '41 Plymouth road racer (Page 1 of 3)

I'd go the LT1 route with the t56.  The mag 5.9 and the nv3500 are good parts, but they are truck parts and perform accordingly.  IIRC the ratios on the nv3500 are a little wider, and probably not as conducive to road racing as the t56.  Not to mention that the LT1 gets you 275 to 300hp right out of hte box and the 5.9 magnum gets you 245hp at best.  Most likely you'd be looking at a 5.2 with 225-230hp

It comes down to this:  Are you building it to be driven more like a dodge dakota pickup or a camaro?

In other words, do I plan to haul barrels of red phosphorus to my meth lab or run over pedestrians while doing Jack Daniels-enhanced donuts in the Circle K parking lot? Tough call!

You're in Colorado, STi swap. They do make rwd kits.

Another good option in the SBC family would be a 6 liter LQ4 or LQ9 out of the early 2000's GM 2500 trucks.  They were available from the general with manual gearboxes, but those may be tough to find.  The LQ motors themselves are becoming relatively cheap these days whereas the LS engine series is still commanding a premium because of the lightweight aluminum block.  Going this route would give you all the benefits of an LS motor (minus the weight...the LQ motors have iron blocks), but at a fraction of the price.  Third gen small block chevy motors are very swap friendly, and have an ECU that's got a lot of aftermarket tuning options.

Hell, the garden variety 5.3L GM truck motor is good for 300-ish HP, although I don't know what options there are for manual trans.

According to the interwebs, GM put both the NV 4500 5-speed and the ZF S6-650 six-speed in trucks with LQ motors.  The NV 4500 is probably the better choice for this application.  Both trannies have the same final gear ratio, but the six speed option has a crawler gear.

I did some quick reading and it looks like you can get the ECM flashed to ignore the auto tranny stuff on the Vortec ECMs.

This site indicates they can do it:
http://www.pcmperformance.com/programming.html

As the owner of a Dakota 5.9 R/T, the answer is "YES" .

Loads of fun in the twisties, gobs of  torque and power in all the right places. A few simple mods away from being a real monster right out of the box. Plus the indestructibility of a @#$% cockroach. Not to mention dirt cheap (i.e. overlooked in junkyards).

You can get a lot more than 245 out of them with some simple home-brewed mad-scientist ingenuity. A LOT more.

Drive it like a Dakota, definitely.

One of these will drop right in:

and it meets all of your requirements except #4.   In compensation, however, it would be a thing of great beauty.

It's hard to find a 360 with the 5speed, but there's a decent # of 318's and 5speed combo's out there.  Throw a new cam and a set of slightly shined up EQ heads on there and you've got 300 hp.  If the budget allows, you could throw a 4inch stroker crank in there and now you've got 390 cubes but that would probably(almost certainly) exceed the capacity of the factory EFI system.  S/F.....Ken M

a manual trans is easy to do behind any LS engine- you can get a T56 out of a 98-02 F body, 04-06 GTO, or Pontiac G8 and it all bolts right up like it was meant to be there- flywheel and everything.

it's also stupid easy to bolt up any trans that is meant for an old school small block with a certain flywheel (i think 99-01 6.0 truck) and throwout bearing (i think the one from a 98-02 F body with an LS1..) and a bellhousing that will clear the 14" flywheel.
so you could run anything from a 3 speed Saginaw with the shifter on the column (3 on the tree- whee!!) to a Saginaw 4 seed, Muncie M20, M21, M22, or Super T10.. or if you like overdrive and don't mind changing transmissions every once in a while a T5 out of an 80's F body.. Ford toploaders are also an option with a special pilot busing and clutch disc, or you could keep it in the Mopar family and put an A833 overdrive in it..

the computer is almost as easy to deal with- just get LS1Edit and a laptop and remove the auto trans parameters from it..

The cummins is sexy in it's frame distorting mass & power sort of way.
But the Atlas inline 6 from a trailblazer.bravada/9-7x is the way to go.  It's physicaly a little large to fit in most cars, but will fit in this hood just fine.
All aluminum, 300HP stock.  More power with a chip.  Much mores with a turbo.

Though the 6 was not available w/ a manual, the manual trans (NV3500) from the modular 5 & 4cyl atlas engines will bolt up.

GM EFI architecture is easily reflashed to ignore the loss of auto trans, catalysts, rear O2 sensors, VSS, etc.