Help me sort my combo

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So its time to freshen my 20 year old build. Specifically I'm looking to improve my cam choice and match the torque converter, which my present combo doesn't. The goal is a zippy street ride that doesn't embarrass me. What I've got

69 dart gt convertible with frame ties and SS springs
3.55 sure grip
727 rebuilt auto with shift kit
2500 boss hog converter

400 from 76 New Yorker rebuilt
polished cast crank reconditioned rods
l2388 F 40 trw pistons yeilding about 10.1:1
Mopar 509 purple shaft cam
Stealth heads gasket matched
Edelbrock rpm performer intake
msd distributer and 6al ignition
Speed demon 750 vacuum secondary
a body big block exhaust manifolds into 2 1/2" dual exhaust with crossover
Be cool rad

Not trying to squeeze the last HP, just reliable and responsive. I'm hoping to hear from similar combo's that work well. Thanks for any and all input!

dart1.jpg
Dart2.jpg
Dart3.jpg
 
Well you got me worrying about my combo now. I didn't think my similar build would embarrass me lol. I had better keep an eye on this thread.
My build sounds very similar although not yet finished if I need to tweak it now the time
400/451
10.5:1
Camshaft not selected going hyd roller
Ported stealth heads and rpm intake ported and matched
Comp magnum roller rockers
Shumacher mounts and tri y headers
Holley Sniper
 
I would recommend a higher end torque converter, Shumacher tri-y's and Rob's cam suggestion.
 
Even with 10:1 that's a LOTTA cam. A LOTTA no cylinder pressure building cam. As for cam I kinda like this one:

RB & B Series Mopar Hydraulic Lifter Camshaft

Honestly though, you need more gear than just a 3.55. I have been trying to figure out for years why that gear is so coveted among the Mopar fold. It's the best of nothing. I would use either a 3.91 or 4.10.
 
Even with 10:1 that's a LOTTA cam. A LOTTA no cylinder pressure building cam. As for cam I kinda like this one:

RB & B Series Mopar Hydraulic Lifter Camshaft

Honestly though, you need more gear than just a 3.55. I have been trying to figure out for years why that gear is so coveted among the Mopar fold. It's the best of nothing. I would use either a 3.91 or 4.10. Now, if you make the gear change, you might look at this cam instead:

RB & B Series Mopar Hydraulic Lifter Camshaft

Even with the smaller cam, I would still recommend the gear change.
 
Garrett Ellison said:
I would recommend a higher end torque converter, Shumacher tri-y's and Rob's cam suggestion.
Click to expand...
Well, I limited my response to the engine but now you mention torque converters, I’d call Lenny at Ultimate. *I Think* he is keeping his exhaust manifolds. Otherwise, the current combo should have had them long ago.
 
When I first put this together in 98 I wanted to put a big block in and keep the power steering and power brakes, just as if it came from the factory like that. There weren't a lot of piston options available back then and I had to butterfly cut the pistons when I added the stealth heads because they changed the geometry just that much. Sure don't mind a new converter, never been a fan of the one in there. Thanks for the replies yall.
 
Boss Hogg converters are cheap for the Chevy guys so they can say they have one. lol If you go that route, I would call a good converter company and get one custom made. Frank Lupo, Dynamic, PTC, Precision of New Hampton just to name a few.

Oh and put headers on the damn thing.
 
Are those original A body big block exhaust manifolds? If so, you might consider selling them for big bucks and buying a set of high quality headers such as the TTI 1 3/4 inch. That should free up some cash and some power at the same time.

If it was my car I'd probably get rid of the 509 cam and switch to something like the Mopar .528 solid or maybe even a touch smaller than the .528 solid. It is easy to over cam an engine and if you aren't super sharp with the carb tune then the car isn't much fun to drive. Another option would be to ditch the carb and to put a Holley Sniper throttle body on there. If you are interested in tuning the Sniper will be a lot of fun. You'll be able to watch how the engine works with the Sniper data logs and you'll be able to tune it with a laptop rather than a screwdriver.

If you insist on keeping the exhaust manifolds then you'll have to change the cam. That cam sucks with cast iron manifolds. If you want the engine to run hard with the manifolds then you'll have to work with a cam guy who knows what to do with manifolds. Porter Racing Heads is the only guy I'd trust if I wanted to pick a cam to work with manifolds.
 
I don't know anything about bigblocks; but I like me a 230 cam allrightee. Nice pick Rumble. After you get that in there with headers, you'll wonder what the heck you were thinking when you installed the 509. At least I did, in my lil 367,lol. I gained so much zippy it was frightening!
I now run 3.55s, but I have a stick, no TC for me. And first gear is just used to get to second lol, where all the action is. The nice thing about 3.55s in my combo is I hit 5100@60 at the top of second, just under peak power. For you, 3.55s suck cuz at 60 your engine will barely hit 4000.
But for you, 35mph will be at or near peak torque in first gear, so when you hit it, and it kicks down; hang the heck on!
IDK,I had a bad experience with a 440 in hi-school.
My Swinger went 98 in the quarter on those factory E70-14s. Another kid in grade 11, said his Daddys 68 NewYorker could take me. I said com'on it's a family car get outta here. Some weeks later I got tired of him bugging me and said OK, We'll go to a hundred, on my speed-O. Of course the lil Swinger jumped ahead and by the top of second that boat was a distant memory. Then a funny thing happened. About 85mph this boat is getting bigger and bigger in my rear view mirror, and we got 15 more to go!
Well ya know 3.55s are a lousy gear to hit a hundred with using a Mopar 4 speed; it's too high for third and too low for fourth. So if I shift, I'm thinking I might be done for. But my 340 starts floating the valves about 5600 and I'm still done for. What to do what to do. Well ya know I gotta shift right? and so about 90mph, Bam I smoked that stick into 4th, the Rs dropped into basement and just like that,that ugly brown tub is on my back bumper, and inching alongside. I don't know how that lil 340 held him off, but I did reach 100first. (He mighta had to shift too,with his touring gears,lol.)
I never raced to 100 again with 3.55s... I went straight away,and got me some 4.10s. With a trac-loc. Which I still have to this day. $65 I paid for the whole 2881489 shebang.
I gained a lotta respect for 440s that day.
True story from 1971, going on 48 years ago. Criminy I'm getting old.
 
I'd do 3 things to that combo

1. Gear vendors Overdrive
2. New cam
3. 4.10 gears

That TC will work, You ideally need a higher stall but it will work, especially with a better cam.
 
In my original 400 I used a Crane 683801. It was a great street cam ground on 114 lobe centers which made it idle very well and it had lots of low end torque. The Summit 6401 is basically the same cam at half the price.
 
qkcuda said:
In my original 400 I used a Crane 683801. It was a great street cam ground on 114 lobe centers which made it idle very well and it had lots of low end torque. The Summit 6401 is basically the same cam at half the price.
Click to expand...

huge fan of bigger LSA's as well
 
First question...... which 509 cam?
There are two...... 108lsa or 114lsa.

The 114 would be “better” than the 108 for ex manifolds, but neither are really a good choice for that combo imo.

If what you’re really after is “more power”, put headers on it.

If you want more power and still have really nice street manners, put headers on it and a solid flat tappet cam.

If you’d be happy with better response and low end grunt....... put headers on it and a smaller cam.

If you really want to keep the ex manifolds, I’d put a smaller cam in it...... which would offer better response and drivability...... but would do little to actually increase the amount of HP.
 
I bought the Crane cam because I was originally planning on running exhaust manifolds, and it was a split duration 222/234. I thought the extra exhaust duration would help. Is that theory correct? Never got to test it out, because of the cost of big block A body manifolds, I ended up running headers.
 
Yes that’s correct. Larry Shepard suggeg tbe split to be 8* - 10* longer for the exhaust.
 
I'd bet my left nut he's got the .509 cam with the 108 LSA. Gawd I hated that cam when I ran it.
 
roccodart440 said:
I'd bet my left nut he's got the .509 cam with the 108 LSA. Gawd I hated that cam when I ran it.
Click to expand...
I`d consider what Andy said , put headers on it, no factory big block exhaust manifolds are wortha ---- !
The 426 hemi manofolds and the max wedge manifolds are amoung the best, and they ain`t ---- compared to real headers !
Boss hog , chevy stuff like RRR said.
 
I actually think the 509/108 cam is a great hot street/strip and bracket race cam........when used with the appropriate supporting parts, in the right application.
It wouldn’t be my choice for a 3.38 stroke build 95% of the time(and never for anything with the current pricing. I can’t imagine anyone forking over $475+ for that cam & lifter kit).

I think it would be “fine”-ish(although probably not optimum) in the OP’s motor....... if used with headers, 4.10’s, and a decent 9.5” or 10” converter.

Something along the lines of the 528 cam certainly offers similar power along with better/improved drivability.
 
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PRH said:
Something along the lines of the 528 cam certainly offers similar power along with better/improved drivability.
Click to expand...

This is Exactly what I switched to in mine and was so much happier. No albeit I made some other changes over time it liked as well.
 
Thanks for all the knowledgeable input guys. Every bit is helping me to focus more on what I really want. Some like blonds, some like brunettes, some like 1/2 ton pickups! Hoping to not have to cut the pistons more, so it looks like .509 is about the maximum lift unless there are some trick ramps. I'm probably looking for a lower rpm power band so the ex manifolds don't choke it off to much. And I expect a different modern converter will do much better things for transferring power under less than full throttle applications as well as flashing when the cam wants it to. I really appreciate the contact information on good techs in the cam and converter fields. When this is completed I'm gonna have it dyno tuned to see what actual improvements I've realized. I'm so glad to hear from people who can make a small wheel well Dart bite, who can develope power with low rpm limitations and real world experience in similar combo's. The worlds best are right here.
 
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Looks like your plan is a step (or 2 ) above everything I have planned. Bet you kick azz!

Hallzy said:
Well you got me worrying about my combo now. I didn't think my similar build would embarrass me lol. I had better keep an eye on this thread.
My build sounds very similar although not yet finished if I need to tweak it now the time
400/451
10.5:1
Camshaft not selected going hyd roller
Ported stealth heads and rpm intake ported and matched
Comp magnum roller rockers
Shumacher mounts and tri y headers
Holley Sniper
Click to expand...
 
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