Need some advice on choosing an engine

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Garry in AZ

Garry in AZ

Building a 9 second Valiant
Joined
Jul 13, 2017
Messages
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Location
Mesa, AZ
Okay, I am just in the planning stages of this build, so nothing is etched in stone. Here's what I think I'm going to do, and I'm looking for opinions, suggestions and instruction from those who have already been to the movie. Might as well learn from the experts, right?

This will be my first MOPAR build in over 20 years. The car is a 1967 Valiant 100 two-door post. It's an Arizona car, fairly straight and rust free. Currently has a slant six and somebody's four speed. (Was a column shift car) I want to build a fun street/strip car that has a lot of torque, and will run in the 10's. The car won't see more than 1000 miles a year, but could be taken to the dragstrip and bracket raced fairly regularly. Consistent performance is important. No plans to drive the car anywhere other than the track and local car shows.

My initial plans are:
Completely strip the chassis of all the OEM running gear and suspension.
Install new AlterKtion front end, with coil-overs, rack and pinion box, Wilwood brakes, eliminate the torsion bars.
The rear suspension will be a Reilly Motorsports four-link coil-over setup with a narrowed Dana 60 or 9" and disc brakes.
Weld in frame connectors and torque boxes.
Mini tubs.
29.5x15 rear tire
4:10 gear
Automatic trans with transbrake. (suggestions welcome. 904, 727, or ??)
Line Loc.
Now here is the part I can't decide on... what motor?
Budget for the motor and trans is around 15 grand. Would love a 6-71 sticking out of the hood, but not sure I can afford it. So....
440?
Stroked 360 (408) ?
Gen 3 Hemi?
Max Wedge?
Looking for 500+ ft.lbs torque and lots of low RPM grunt so not too keen on a small block, but willing to listen to the experts.

Whaddya think?

Garry
 
I did a lot of work on Tim's red Valiant which was a similar project. We went with a 427 inch SB engine which worked out pretty well. That engine made the same torque and hp as an early Viper engine so it was basically like having a lightweight Viper. That car would go 160+ mph on the road course at Portland International. But after we were all done we both agreed it would've been easier and cheaper to have used a Gen 3 Hemi. I wouldn't even bother considering a big block for a project like that. Gen 3 or LS (if you're brave).

Oh and you might not need the AlterK. The stock type suspension works just fine for road racing or drag racing. Not even sure you need the multi link in the rear although there might be some merit to it. You should spend some time looking at the Green Brick and Tim's Red Valiant. Those two cars kick some serious *** and they both have stock type suspension setups and SB engines. I think Eberg is converting to a Gen 3 but I haven't seen an update in a while.
 
You should first figure out what you want for a power plant and then build from there.

904 for the small block
727 is the only auto choice for a big block.
 
Thank you both for the replies. I will take your suggestions into serious consideration. I will also try to find out more about the two cars mentioned.
I may be doing it "bass ackwards" but I always build the chassis first (based on my hp and tq goals, and what I'm going to do with the car) and then make final decisions on the engine. The reason I'm probably going to go with a new front suspension is because getting rid of the OEM steering box and the torsion bars makes the installation of any engine and headers much simpler. It also saves weight and allows me to run real brakes more readily.

Thanks again! Much appreciated.

Garry
 
Here are some pics of Tim's Red Valiant. It had "real" brakes on it whatever that means.

427.jpg


baer.jpg


Bilstein.jpg


cornering.jpg
 
Hey Gary, at the risk of sounding like a party pooper, sorry if I did earlier. I myself love a small block and would say to use one BUT a lot depends on the owner of the car.

It is hard to beat cubic inches. AKA big block.
On the flip side, you could save a few pounds with a small blocknthat can be stroked to more than a simple 4.00 arm provides.
There are 4.125, 4.15 & 4.25 stroke cranks for small blocks out there now.

Couple that with the bore size and you can get a decent amount of cubes quick.
Add Victor heads and 1-7/8 headers with a reasonable roller cam and I think it is very doable.
 
Torque is easy to figure out most general (non pro) built engines is gonna fall around 1.15-1.25 lbs-ft per cid which for 500 lbs-ft would be 434-400 cid.
 
Since your starting from scratch I'd go big block. Mainly cause of head choice, hard to pass up on the trick flow heads.

Either 383 or 400 for 434 to 480 cid or 440 for 480-512 cid.
 
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Lee (LilCuda) put Viper calipers on his old (and my old) '66 Barracuda before he sold it to buy the Tim W. Valiant (which he has sold and has been sold again). There is zero NEED for aftermarket suspension. If you want it, fine, but you don't need it to build a serious road course car.
 
I vote for a 392 G3.

Awesome engine in stock form and can be a beast with some work.

Will likely be going that route once I get tired of my 408 (which I also love).
 
Wow, this is a great forum! Thanks to everyone who replied, I am definitely listening to all the advice and information.
To clarify things a bit, the car will never see a road course or autocross. It might not even get sway bars. It will spend most of it's time at a 1/4 mile dragstrip, and it will see street duty driving to and from local weekend car shows etc. It will never see a trip of more than 100 miles or so. No AC, no heater, no sound deadening, mostly aluminum interior, full roll cage.
Cornering isn't a big concern, I have another car I built for that stuff that I take to Bondurant a few times a year. The Valiant will be a straight line, fun burnouts, wheelie pulling (?) adrenaline rush.
I realize that a straight line car certainly does not need the aftermarket suspension I have planned. But for the 6-7 grand it costs, I will have a lot of adjustability, a ton more room in the engine compartment, and the adjustability of the four link will help me in terms of getting the car to launch straight and transfer weight better. For me, the cost is worth it.

And I also fully understand that when I'm done, I'll have $50K+ in a car that I might be able to sell for half that. But the fun of building it and racing it is worth the difference to me.

Thanks again for all the input, keep it coming!!

Garry

P.S. Andy, I ordered your book. Thanks!
 
On behalf of the crew here, your welcome. LOL!
273 said:
Since your starting from scratch I'd go big block. Mainly cause of head choice, hard to pass up on the trick flow heads.

Either 383 or 400 for 434 to 480 cid or 440 for 480-512 cid.
Click to expand...
I actually, really like this thought process. Even if you just grabbed a 383 and used a RB crank, that would be 426 cubes? (Correction sought) Or a stock 400 or with a RB crank for 451 cubes.

The only drawbacks to the big block are washed away by the pros over the cons.
The big block is heavier and uses the heavier 727 which requires more power to operate.
The engine itself is heavier. By a fare bit. They can be lightened up to a small blocks weight.

However, even at an equal cube face off of a stroke small block, AKA, 408 vs a .030 overbored 400, the available heads with larger valve sizes is a great plus, (Edelbrock head vs Edelbrock head for an example) , header tubes start larger. This all will create more power over the small block.

I don't know what you'll end up doing but have fun at it and post it up!
 
I don't know why the 383/3.75 ain't a more popular package. When done you got a slightly smaller bore and cid than a 440 but it's smaller dimension and lighter internally and externally with parts nobody wants.

If you think of a 383 in small block terms. Like is someone made a heavy duty 225 lbs 4.250" bore, deep skirt block that could high hp loads, and tall deck so it could be stroked to 500 cid people would be tripping over themselves to buy one for thousands of $$$$. But call it a 383 big block nobody wants one lol.
 
I had the following build many moons ago. It ran 10.70's in good air at 3400 pounds. I weigh over 300 as driver.

30 over 340 block(360 will work fine as well)
4 inch steel crank
Eagle H beam rods or similar
Zero deck flattop pistons
Ported eddie heads( Modern cylinder head has an excellent cnc program, that will make plenty of power) in fact having them do it would make more power than my stage 2 Hensley racing eddies did
727 or 904( i ran 727)
Typical 28 inch dot slick( hoosier Qtp's in my case)
8 inch convertor suited to combo
4.10 gear will work( had 4.30's at times as well)
Good hp carb, likely a 950( i ran a 1025 4150 race demon)
260/266 comp flat tappet with 1.6 crane rockers. Ended up 598/623 lift
Weiand excellerator intake
On several occasions i drove the above combo 70 miles round trip and layed down 10.70's and Eighty's consistently.
Was about 11.7 compression, mixed in some 110 with pump premium

I like the idea of a small block in an A body. Lighter, WAY easier to work on. Gets ultra tight with header fitment with a big block. Just no room, you will get tired quickly of fighting everything
With the 4 inch crank these days, makes it a no brainer
Btw, i just ran the TTI step headers on that motor( 1 5/8 to 1 3/4) i am sure a 1 7/8 tube would have made more power
 
273 said:
I don't know why the 383/3.75 ain't a more popular package. When done you got a slightly smaller bore and cid than a 440 but it's smaller dimension and lighter internally and externally with parts nobody wants.

If you think of a 383 in small block terms. Like is someone made a heavy duty 225 lbs 4.250" bore, deep skirt block that could high hp loads, and tall deck so it could be stroked to 500 cid people would be tripping over themselves to buy one for thousands of $$$$. But call it a 383 big block nobody wants one lol.
Click to expand...

That's what we are doing with a 383. 4.25 x 3.375 to 4.28 x 3.75. 431CI result

Builder thought he had 440 but it was 383. Great shape. So I said heck, let's see what we can do. Should spin up to 7k+ like SB but with decent low end torque.

Ross pistons.
H beam connecting rods.
Scat 4340 crank
Harland rocker arms shaft set - Harland Sharp S70015KS HD
Pushrods - Smith
Morell lifters solid roller lifters
Milodon 21185 - Milodon Chrysler Dual Line External Oil System.
Milodon pan - 31161 pan
Intake - Edelbrock Victor Intake Manifolds 2886
Coil set - MSD Blaster Coil 82658
FAST Throttle Body 307603
65 lb injectors
Run by Fuel Tech FT500 with
Magnafuel EFI fuel system. MP-4815 kit

Howard cam - 721883-08. DURATION: 263/269 (in/ex) at 050,LIFT .675/.650, LSA 108 degrees

Trick Flow® PowerPort® 240 Cylinder Heads for Big Block Mopar TFS-6161T784-C00. 78 combustion/240-74 in-out, 2.19/1.76 in/out valve, .700 max lift

Meziere remote water pump

Magnumforce front end kit. So gone with torsion bars. Customer headers (No choice like B3 says. Tight!) should be built this upcoming week.

Not cheap. But not crazy either. Built/designed for strip but to also survive Drag Week.

We should see in couple weeks what the dyno says.
 
@273 Yea man, Chrysler made MILLIONS of 383's. While not exactly huge in cubes for a big block, stroking one produces a favorable amount of cubes. Even in its stock form, it has a advantages like I stated up top.

Still ( @B2422w5 ) has a really good combo in a weight savings advantage that will indeed give a many of engines a good run for there money. As well as the weight savings, other advantages over the big block would be more room, easier to work on, (904) less of a power robbing trans. There are some really good go fast parts for the small block.

Looking forward to that @Deucemopar
Sounds like a fun build.
 
For a street/strip toy I'd do a low deck stroker(470-500"). With the RMS sub frame and some aluminum engine pieces(heads,intake,wp housing,etc)the weight difference is a non-topic. You won't need to have huge squeeze and big cam or spin it hard to make your goal which will improve streetablility. 10.5:1 and a good solid roller with a decent head and converter and it'll be a handful of fun! Sounds like a great build...keep us posted!!
 
Few people do the stroked 383 block because the 400 has the largest bore of any Chrysler big block and takes all the same parts (except pistons). We sold all of my son's 383 parts after I picked a 400 block for him. Some day he may get the car back together, or not...
 
rumblefish360 said:
Looking forward to that @Deucemopar
Sounds like a fun build.
Click to expand...

Thanks. Will be interesting. Lol

@Jim Lusk you're right. 400 is optimal for sure. If we need any more from the 383 ... a 100-shot can always do it. Lol

My buddy has stroked 400 and not a really radical cam. Good heads. It's in an e-body and he walks a buddy of his who dropped a 426 hemi in his e-body.
 
When building a fun street engine the difference between starting from a 383 or 400 is minimal. Yes 400 bore is bigger and always gonna be worth 20 cid if both built with same stroke. But 383 bore is far from small and really what's gonna change in a under 600 hp engine. Hp will be practically the same and about 20-30 lbs-ft more for the 400 which is about the same as adding 0.15:1 more rear gear. Same argument could be used for 340 over 360 even thought gains would be slightly less but 360 is the main stroked sbm because it's more available and cheaper even though it gives up a few lbs-ft and cfm of breathing room.
 
Talk about great feedback... Thanks to everyone!
I definitely have some decisions to make. One thing I have decided, is I will most likely be buying a crate motor instead of building it myself, primarily because of cost and my lack of experience with building MOPAR engines. If it was a SBC or LS, I'd likely build it myself, but not if I go the stroked 400 or similar route. I'd like to end up with somewhere between 600 and 700 horsepower at the rear wheels. Assuming I can keep the cars weight under 3000 lbs, that should get me well into the 10's which is fast enough for me. I have heard about the intense care and feeding a 9 second street car requires, and I'm not ready for that.

Thanks again to everyone for the great advice and sharing your wisdom with a guy just getting back into MOPARs.

Garry
 
@273 How does the 360 give up cfm in breathing room?
By what is the bassis for the 360 giving up a few foot pounds of torque? In what form vs. what other block?
 
Gary, you won't need that much power. But hey! Why not!
 
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