340runner
Well-Known Member
Would you reconsider the gearing statement on either a 400 block stroked with a 440 crank or a high compression 440, all forged bottom end of course, pushing on either engines around that 500 to 550 hp mark NA, and then with a 100-150 shot? It's basically i can either spend money to regear back to 4.10s, which I have the gears but still need everything else, or would you think 3.55s have enough punch on the bottle?Fill your library before you fill your garage,
words to live by, read get educated on how an engine really works
what it takes to make a chassis work
Mopar Performance has a crapload of books to do all of it
already spelled out for the most part for you, they did it already
you don't need to reinvent the wheel again, they already did it
you're already handicapping yourself by going with a manual trans
I won't even try to talk you out of it, your stuck on it, so deal with it
you'll learn sooner or later after breaking a bunch of stuff
I know it's fun, I've had many fast cars with clutches...
make a plan & stick with it
don't go all over the map & get lost in a number
it will cost you a lot less than experimenting with crappy combos
the experts are out there, a phone call (talk to a pro on each aspect) or website away
I'd stay away from e-mail **** facebook, Instagram
the venders will rarely respond, consistently or repeatedly especially after a sale, for tech
trust me I've been there, done that for 45+ years now
gears, & the 8-3/4" for a manual trans for a street/strip combo car
it's always a compromise, weak, but can be made way better...
I always sided on more gear, a steeper gear, bigger #s, than a 3.55:1
(unless you make a hug HP/TQ #s to pull them higher gears, still a compromise)
3.90:1 min. gear, more so a 4.10:1, or taller tires & 4.30 or 4.56:1
or steeper with bigger/taller tires, IMO win, win it's more rubber to the ground
moves a heavy car way easier, torque multiplications of steeper gears,
& a bigger footprint
IMHFO the 340 is weak link in the (your) equation, no offence
you don't even know what it has in it, you need to know that stuff
everything else is dreaming stuff
I know what it was like to be a teen & want a fast car I always had one
it's expensive & you sacrifice a lot of other stuff to get it
you are handicapped already, small engine (340 in a 3700+# car with 400# of torque),
not much torque, in a big heavy car
again no offence meant, just facts truth realistic stuff
to want to go fast in a heavy 71 B-Body car,
or screw up a #s matching deal
but you can work with it
& if you don't care about not spinning a bunch of RPM, like 3,500 (+) at 55 on the hi-way
get a 4.10:1 rear gear a 28" tall or taller (more roll out, & wider the better)
you sort of want like a 10:1 in your 1st gear ratio for drag racing at a min,
1st gear ratio X the rear gear;
example 1st gear 2.45:1 x rear gear 4.10:1 = 10.05:1
example 2.45:1 x 3.55:1 = 8.69:1 yours not cutting it for a non boosted heavy car
unless it's boosted or N2O a completely different animal than a NA engine
Need stiff sidewall Bias-slick
or same in a Drag Radial, needs to be a stiff sidewall for an manual trans
stiffer sidewalls takes a big shot/hit better
you could get a GearVenders over/underdrive, they ain't cheap either
that's in the dreaming realm probably, but will solve the street strip element
all about power to weight ratios, less weight takes less to move it
some aluminum parts where you have steel, brass or cast iron helps too
or fiberglass bumpers/aluminum bumper brackets
& fiberglass hood, will help some but sacrifice looks, if not done right
not exactly cheap for good fiberglass nowadays either
weight off the front to get weight transfer, your car obviously needs badly
**edited added; forgot to mention it
Free, just a bit of time
disconnect the front sway-bar links at the track too,
zip tie up the bar or take it off save a few #s too, at the track
but it helps on the street for handling
But at the track, without it, will help to lift the front more, weight to transfer to the rear**
maybe a trunk mount battery, I know all the naysayers
downfalls, you will need to have a remote shut off switch, to run at the track
but a great way to get a bunch of weight off the front/nose
& add to the rear (right rear)
double what you took off the front on the rear wheels
do something about traction aid, you'll need it
good adjustable (or dbl adjt.) QA1 or Rancho shocks are relatively "cheap"
in/for what you get
they will help a bunch, especially on a stick car
you will still need stiff sidewall Bias Ply slicks or Drag Radials too
Calvert CalTracs work on leaf spring cars,
easy bolt on stuff & they work, been proven run in S/S or Stock Eliminator
I had one going, street driven a lot drove to the track & cruised a lot too
best of 8.58@156 w/a 1968 383/479cid low-deck w-A727 4,200rpm vert,
in a 68 RR RM23 HT on M/T 315/55/15 Drag Radials, drove all over Sacramento
sold it to a guy still in Sac., be aware of a sliver 68 RR w/black 6bbl lift off hood,
Halibrand kidney slots, a lil' lower than stock, he'll blow your doors off
(383 block, lots of $$$ making it work, I know what it takes, been doing this **** since 1977,
going 8's or faster, since I was 17 & it's not for a novice, I had a lot of great advice, my elders)
A 4 link;
no matter which is a bunch of fab work, any of them requires some welding
& 4 link really isn't for a novice either
some like the QA1 or Ride-Tech stuff, are triangulated 4 link
are a bit easier tuning setting up, still aren't bolt in need welding, a experienced welder
a real 4 link race set up is not for a novice, lots of research needed, planning etc.
& right shocks are critical, in either equations
A 383 block albeit you can find them cheap, there's lots of used up junk out there
they made millions
BUT it is the weakest of the Big Blocks,
a 400 low deck block is way better (even better than a 440 block),
have a bigger bore too, more cubic inches, in the same real-estate/engine space
They have thicker webbing on the mains,
if you want 700hp, the webbing in a 383 block, won't last long before it cracks
or you get main-cap walk, even with a girdle & studs (I know)
But; a cavate
you can very easily get 500+hp out of a good combo'd 383 'easily'
you still will need the same deal
*a good set of heads flowing 300cfm at a min. at 0.600 gross valve lift
*a good matched cam, springs, retainers & valves, adjt. rockers etc.
(not stock ****/stamped steel)
*a good compression ratio, forged piston, at or near zero deck, w/good quench
piston at the top of the deck, with proper valve relieve to have good valve to piston clearance
for your specific camshaft, IMO a min. 0.540" gross valve-lift,
you can get there with an adjustable 1.6:1 rocker (rollers) if needed
*a good induction/intake & carb (I prefer Holley style carbs over any Carter or Edelbrock)
street/strip, street driven a lot a Edelbrock Performer RPM is a great manifold, dual plane
with a 1" spacer/tapered 4 port or open
a single plane can work too, a 1" 4 port tapered spacer will help drivability/street manners
*a good ignition, to burn the excess fuel you will need to make HP
*the right gears for the camshaft & complete engine trans combo
*headers (long tube, you said you have) but an 1-7/8" min. if the room is there 2"
'or' at least at the size or bigger of the exhaust valve diameter
you can get that more easily with a 440, it's 4.320" bore x 3.75" stroke
more cubes/more torque
but not the best block IMHFO
**or in a 400 low-deck (smog era) block will live longer,
unless you have an expensive aftermarket RB block
because of the webbing strength or thickness in the 400 blocks,
is considerably stronger & thicker
common put a 440 crank with smaller mains diam. of a low-deck 383/400 block
a lil' bigger bore to start with too
400 is 4.340" bore stock x 3.375" stroke, stroke same as the 383
& 0.030"/4.370 over & a 3.75" (440 stroke) crank is like 449cid
or (most I'd dare go bore wise) 0.060" over 4.400" x 3.75" stroke is like 456cid
(buy one made for it, the radius of the counterweights have to be turned down to 7.125" too
expensive to do all the necessary machine work, member @PROSTOCKTOM
sells/has some great priced & good parts/stroker kits)
there's a lot more to a combo, than just a manual trans & an engine combo
you can make a crapload of power & never get a good time
if the whole combo isn't set up correctly, the car too
you're young, "I assume" study &/or read about it
lots of great books, you can use & look at repeatedly for reference sake
MoPar Performance is just one good source for chassis or suspension or engines/combos
OK I'm done for now, lecture perf. 101 is over
a lot of good advice from a lot of respected members here
listen & you will learn from most of them
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If you haven't been able to tell from my recent posts, I find nitrous as a alright cost effective way to have power when you need it, and not when you really don't
I'm finding good deals on used slicks, but everything is 28x10.5 so I'll be undergeared
I do have friend where his father has quite a bit of experience regearing, so I should be able to pull it off
Another option are the 4.30 to 4.89 gears floating around marketplace for my axle spline for around 800$, but they're on spools, which should work at the strip but id like something that I can also run stoplights with
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