Build My Big Block

[PurpleBeeper]

I'm looking to "somewhat" transform my 1970 Road Runner 4spd car into a long-distance cruiser (on a budget of may $5000 TOTAL & $3500-$4000 preferred) instead of the stoplight street-racer it's always been. I need some advice on how to build the motor & where to spend (& not spend) cash. I do 98% of my own work and have built 8 engines (but I'm no machinist). IF POSSIBLE, I'd like to build a 2nd motor & keep the current one on an engine stand.

Here's how the car sits now: (licensed & running):
440 stock stroke, balanced, big rod with 2618 forged aluminum .030" over TRW pistons
Externally balanced engine
Iron six pack intake w/70 4spd carbs (close to stock settings)
XE274H Comp Camps hydraulic
Isky ductile iron adjustable rockers, Isky pushrods, Mopar dual valve springs
'71 iron stock valve heads (no hardened seats)
NOS Cheater system
Two Holley blue fuel pumps (one supplies nitrous)
1-5/8" headers & stock style mufflers (need to keep it quiet)
MSD-6A w/MSD multi-step retard & MSD Blaster coil
A-833 4spd, NO OVERDRIVE, Centerforce dual-friction clutch, Lakewood, safety loop
SS leaf springs
8-3/4" posi 3.91 gears

What I'm planning as of now:
2.76 gears (I have a 2nd pumpkin + the ring/pinion)
2618 aluminum forged pistons of some type ("occasional" nitrous use 150-200hp max)
Keep the 4spd (need a drilled crankshaft) - No gear vendor or Kessler (too much $$$)
Internally balanced engine
Strongly considering stock-type non-adjustable rocker arms
Run on 91-octane so I can buy gas anywhere (93 or 100 w/nitrous use)
"occasionally" put the 3.91's back in for local driving

My Questions:
Heads? (I'm leaning towards stock iron '74+)
440source/Hughes Stroker? (I'm leaning "no" but can't find 4spd drilled stock crank)
Compression ratio?
Cam shaft?
Rods? (will the small stock-type rods handle the nitrous?)

All of your comments are appreciated. PLEASE REMEMBER my budget of $4000'ish ($5g MAX). Thanks for your help!

 

[69 GTX]

What's your goal?
If it were me I'd put a comp 21-224-4 in it, change the rear to a 3.23 and call it good! 3:23s should put you in the 2600 rpm range at 75 depending on tires. The cam will give you more torque and be happy at your cruising rpm. Why build a second engine?

 

[RT K_line]

I would get an 833 w/overdrive and swap the gears and nothing else. If you had to build another engine the Kieth Black pistons can handle nitrous along with stock forged rods and crank.

 

[dave dodge]

Good advice from 69 GTX!

 

[Bill Monk]

I agree with GTX on the 3.23 gears, I think you will be happier with them. I would simply go back to a stock configuration including the non adjustable rockers. As for a 4 speed (if you need one). Check out Brewers at http://www.brewersperformance.com/

 

[furryfrog]

Is it fuel mileage your trying to improve mostly? Is your comp ratio as is to high to go down a step or two in cam? Thicker head gasket? Different heads like you are already considering.

I dont know how the 6 pack is on fuel but a manifold swap to a single carb?

I agree with the other guys about 3.23 gears.

Seems to me your engine is already a good street engine. Are you itching to build another engine?

 

[lewtot184]

I would get an 833 w/overdrive and swap the gears and nothing else. If you had to build another engine the Kieth Black pistons can handle nitrous along with stock forged rods and crank.

i'd lean toward this.

 

[lewtot184]

about 3yrs ago I built a "spare" 440 just for cruising around in my 65 coronet. the engine had to run on pump gas and work with a stock converter and 3.23 or 2.94 gear. I used a '70 block, hughes stage I big valve '452 heads, kb184 pistons, rebuilt ly rods and steel crank, stock bearings and clearances, milidon road race pan, howards 225/[email protected]" -.490" lift cam. I do have a ch4b with a 750 edelbrock that I thought about using with it, but a ch6b or ch28 would make more power. it's together but still sitting; get to it one of these days,....lol!

 

[65-440]

long haul cruiser ? Magnum cam, 2.94 gears, single carb ... done !

My 383 is. 030 over, xe268h cam, source stealth heads, 9.44:1 comp, 3.23 gear ... I cruise Hwy all the time, but a diff gear might be nice for the really long drives !

 

[727]

294 gears.

Brewers sells a needle bearing that presses into the large diameter bore in the back of the crank. If the original bushing bore is too small for the input shaft, you could use a hand drill if needed to bore out where the bushing would go to keep from cutting your input shaft shorter.

 

[BBishere2]

What about leaving everything as is and install a Gear Vendors overdrive unit?

Should come in under budget and give you the ability to cruise when you want and play when you want.

 

[wagonman]

I think you are going to be close or over 5K with a stroker kit, new heads, cam and block work. Like said what are your plans for the change? The 323s are a good allaround gear but I have also been thinking of some taller cogs, 276s would make the long haul interesting @ 90 plus.

 

[PurpleBeeper]

Thanks guys for all the responses, but here a few other factors of why I think I need another engine + my goals.

1. My goal is to be able to take 500-1000 mile trips with my family in the car, have it be dependable & run on 91 octane gas. I also want to be able to carry one spare tire that is the same diameter as both front/back. This limits how tall a tire I can put on (I think I can go 27" diameter max. up front, so it's 27" diameter max. in back too). Right now I have 26-1/2" rear tires & I'm running 4000+ rpm on the highway (with 3.91's). I previously ran 3.55's for many years and ran about 3500 rpm on the highway. I know that 3.23's came "stock", but even with those gears (& my tire limitations), I'm still looking at 3200-3300 rpm sustained cruising rpm and this just "seems" too high to me to ensure I don't break down on the highway 4 states from home. My Mustang w/overdrive runs about 2300 rpm on the highway.

2. Just adding a Gear Vendor or Passon overdrive setup makes sense EXCEPT I think I need a new motor. (see below)

3. I built this engine in the mid 1980's. I know it has one piston that's "not just right". I don't think it was properly balanced at the time because I get an odd engine vibration on the highway (have changed driveshafts, still there). It's a big-rod motor that's EXTERNALLY balanced, so the clutch changes I've made over the years may have thrown off the engine balance further. I just don't trust the shop that balanced it (out of business now). The flywheel has been resurfaced twice and still has some heat check marks in it. Also, it DOES NOT have the hardened valve seats ('71 heads) and when the heads were done, the guides were knurled instead of being replaced. Lastly, both the block deck + the heads were milled (two different shops) and I'm not sure how much on either. I've always had a hard time getting intake manifolds to seal.

It is a 4spd car and I'd like to keep it manual. In the mid 80's when I first installed this motor (or actually when I tried to bolt up the transmission) is when I found out about the "pilot hole thing" since this 440 has an automatic (non-drilled) crank. At that time, I took the new motor apart & had a machine shop drill the crank, BUT the hole STILL wasn't deep enough, so I've already cut 1" off the nose of the transmission. I do now run one of those needle bearings in the back of the crank flange (hadn't been invented in 1985), but past experience tells me I NEED a drilled crankshaft and I have never been able to find one. That's what has had me looking at the aftermarket kits (crank, rods, pistons) and also made me "think" about strokers.

So back to my questions:
My Questions:
Heads? (I'm leaning towards stock iron '74+)
440source/Hughes Stroker? ANYBODY GOT A STOCK STEEL CRANK DRILLED FOR A 4SPD?
Compression ratio? With iron heads - piston recommendations in 2618 forged aluminum?
Cam shaft? Is my current XE274H too big?
Rods? (will the small stock-type rods handle the nitrous?) Does everyone agree that LY rods are fine for 150-200 shot of nitrous?

 

[PurpleBeeper]

about 3yrs ago I built a "spare" 440 just for cruising around in my 65 coronet. the engine had to run on pump gas and work with a stock converter and 3.23 or 2.94 gear. I used a '70 block, hughes stage I big valve '452 heads, kb184 pistons, rebuilt ly rods and steel crank, stock bearings and clearances, milidon road race pan, howards 225/[email protected]" -.490" lift cam. I do have a ch4b with a 750 edelbrock that I thought about using with it, but a ch6b or ch28 would make more power. it's together but still sitting; get to it one of these days,....lol!

Hey Lewtot, your inbox is full. If you don't think you'll use that spare 440 anytime soon and it's drilled for a 4spd, we should talk. Send me a pm when you get a chance please.

 

[lewtot184]

I think the inbox is cleared, but knowing me that may be a crap shoot. anyhow, open chamber iron heads need a quench dome piston or try to get the compression ratio down to 9:1 or a little less. there aren't any shelf quench dome forged pistons but Arias used to make a 10.5:1 for a 440 and should be able to do a 9:1 or so but it'd be pricey. proper cam selection will be a must with a tall gear. Brewer's was making 3.09 first gear tranny's that might work good with something like a 2.94 or 2.76 gear.

pretty sure the crank in the spare is drilled but don't know if it's "finished" drilled or not and don't have a pilot bushing to measure with. not 100% sure I want to get rid of it but i'll think on it. I had some big plans and changes in mind for my 65 coronet but like most people spending the money and big ideas sometimes conflict.

 

[PurpleBeeper]

I think the inbox is cleared, but knowing me that may be a crap shoot. anyhow, open chamber iron heads need a quench dome piston or try to get the compression ratio down to 9:1 or a little less. there aren't any shelf quench dome forged pistons but Arias used to make a 10.5:1 for a 440 and should be able to do a 9:1 or so but it'd be pricey. proper cam selection will be a must with a tall gear. Brewer's was making 3.09 first gear tranny's that might work good with something like a 2.94 or 2.76 gear.

pretty sure the crank in the spare is drilled but don't know if it's "finished" drilled or not and don't have a pilot bushing to measure with. not 100% sure I want to get rid of it but i'll think on it. I had some big plans and changes in mind for my 65 coronet but like most people spending the money and big ideas sometimes conflict.

Well lewtot, those custom Arias pistons are out of the question I'm sure with the off-the-shelf 440 slugs running about $60 each. I will try to keep the compression down to 9:1 (vs. 10.0-10.5:1) since I guess I'm staying with iron heads and want to be able to run 91-octane.

I did consider I might get "clutch chatter" with 2.76 gears, but I went ahead and bought some. I think I'm just more afraid of overheating/trashing the motor after 6 hrs. non-stop 3500rpm cruising than frying a clutch disc (maybe I'm wrong). The 3.09 1st gear make a lot of sense, but if I rebuild a transmission, I'd be putting in one of those $1100 Passon 18-spline O/D kits (want to do this in the future - probably my best overall solution for the car).

Please tell me what I should be looking for in a cam with 2.76's.

Also, what are your thoughts on heads for this type of motor? Do I just need some 74+ heads? Am I OK with non-hardened seats? Should I look for cheap aftermarket heads?

Lastly, if you do consider parting with the extra engine, it sounds mild enough for my use and I could drive out to Indy to pick it up (& buy you a beer somewhere in the Broad Ripple area!) Since my transmission is already cut, I could deal with an in-finished hole I believe. The 73 big rod motor I've got now started off with just a "dimple" of a crank hole.

 

[69 GTX]

From what you've described I don't think you can get it done for 5K properly.

Tires & wheels 1-2K
heads at least 500
cam lifters and rockers 3-500
pistons 500
core crank & block 500
intake & carb 500
timing set 150
gasket set 150
plus machine shop labor

 

[1967coronet440]

It’ll be tough to build a new motor with your max of $5000, might be best off refreshing the motor you have, swap the cam and heads... when I built mine starting with a bare 75 440 block I think I had $1600 in machine work? But the first block I had I didn’t use because it needed a few sleeves, picked up a standard bore 440 for $450..

 

[Mike67]

Do a modern Hemi upgrade, complete drivetrain... dependable, peppy, off the shelf parts and get 20+ mpg... of course it will require some structural mods but it sounds like it might suit your wants/needs cheaper than a new motor,gears... just a thought

 

[1967coronet440]

Do a modern Hemi upgrade, complete drivetrain... dependable, peppy, off the shelf parts and get 20+ mpg... of course it will require some structural mods but it sounds like it might suit your wants/needs cheaper than a new motor,gears... just a thought

I don’t think that will fit the budget of 5k