Re: Cam selection; 340 with manifolds
[Re: BSB67]
#2216666
12/18/16 10:58 PM
12/18/16 10:58 PM
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Joined: Jan 2003
Posts: 727 Ottawa, ontario
dd340
OP
super stock
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OP
super stock
Joined: Jan 2003
Posts: 727
Ottawa, ontario
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I have been running a 69 dart 340 for a few years with a racer brown cam 220* .460 lift cam. It works really good but I would like to increase the horsepower. Any recommendations for a small block running stock manifolds? I would consider a solid cam but would prefer hydraulic. I have stock 2.02 valve heads and stock 10.5 compression. My original idea was to put headers on it but TTI's and full exhaust run close to 2k in Canada so I'm hoping for a better option. Opinions? Based on your opening question and some of your responses I think we need to know your budget, and your expectation. Certainly you can put headers on the car for far less than $2000. I also think that that a different cam will put more power in it too. Your car/motor seems to run about right for what it is, and making any one change will not likely yield a huge gain. Are you running your current combo on pump gas? If so, this surprises me. What is you cranking cylinder pressure? If you go to a cam swap, I would go with a small solid Currently yes I only use pump gas but it tends to knock on 91 octane so I pretty much only run it on 94 which I have easy access to. If I go the headers route I will also swap the cam since I think it makes sense to maximize the benefits of it. It's not so much a budget issue as much as cost per benefit, 2k just seems like a lot for an exhaust swap. The exhaust I have now is all original so I kind of like it as is. My hope was to gain 30hp without switching out my current exhaust but that may be unrealistic.
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Re: Cam selection; 340 with manifolds
[Re: dd340]
#2216675
12/18/16 11:06 PM
12/18/16 11:06 PM
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Joined: Jul 2007
Posts: 11,836 Florida
mopar346
Let me tell ya about fat chicks!
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Let me tell ya about fat chicks!
Joined: Jul 2007
Posts: 11,836
Florida
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Put a gear and a sure grip in it and get you some tires and you'll feel like you gained 50 horses.
Careful, your character's showing!
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Re: Cam selection; 340 with manifolds
[Re: dd340]
#2216773
12/19/16 01:48 AM
12/19/16 01:48 AM
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Joined: Jan 2003
Posts: 2,787 541 slobovia
A990
master
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master
Joined: Jan 2003
Posts: 2,787
541 slobovia
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I have been running a 69 dart 340 for a few years with a racer brown cam 220* .460 lift cam. It works really good but I would like to increase the horsepower. Any recommendations for a small block running stock manifolds? I would consider a solid cam but would prefer hydraulic. I have stock 2.02 valve heads and stock 10.5 compression. My original idea was to put headers on it but TTI's and full exhaust run close to 2k in Canada so I'm hoping for a better option. Opinions? Based on your opening question and some of your responses I think we need to know your budget, and your expectation. Certainly you can put headers on the car for far less than $2000. I also think that that a different cam will put more power in it too. Your car/motor seems to run about right for what it is, and making any one change will not likely yield a huge gain. Are you running your current combo on pump gas? If so, this surprises me. What is you cranking cylinder pressure? If you go to a cam swap, I would go with a small solid Currently yes I only use pump gas but it tends to knock on 91 octane so I pretty much only run it on 94 which I have easy access to. If I go the headers route I will also swap the cam since I think it makes sense to maximize the benefits of it. It's not so much a budget issue as much as cost per benefit, 2k just seems like a lot for an exhaust swap. The exhaust I have now is all original so I kind of like it as is. My hope was to gain 30hp without switching out my current exhaust but that may be unrealistic. 102 is a Nice MPH. My opinion? A good set of DA shocks will be a better ROI than the same amount on chasing the HP left on the table.
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Re: Cam selection; 340 with manifolds
[Re: dd340]
#2216947
12/19/16 01:45 PM
12/19/16 01:45 PM
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Joined: Jan 2003
Posts: 14,539 So. Burlington, Vt.
fast68plymouth
I Live Here
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I Live Here
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So. Burlington, Vt.
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IMO, you're not going to find 30hp from a "simple" cam swap. Swap for a streetable roller??? There might be 30hp there.
When the intake and exhaust are both a "cork" limiting airflow through the motor, finding extra power is a challenge. You need to move more air, so you can mix it with more fuel.
If you're really set on retaining the stock appearance, and want a noticable increase in power( and seat of the pants feel), more cubes is your best bet.
When you get tired of that, you can upgrade the intake/exhaust and really bump the power level up.
68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123 Dealer for Comp Cams/Indy Heads
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Re: Cam selection; 340 with manifolds
[Re: RTSrunner]
#2217598
12/20/16 10:08 AM
12/20/16 10:08 AM
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Joined: Jan 2003
Posts: 727 Ottawa, ontario
dd340
OP
super stock
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OP
super stock
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Posts: 727
Ottawa, ontario
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While a TTI header setup would be nice,there are plenty of good A-body header choices with a lesser price point. Especially for a street based engine.I think a t102 mph you should be in the high 12 second range.Chassis as mentioned or gearing change??What transmission do you have? I have a 727 trans, the converter is really tight, it only flashes to around 1800 rpm. I have been looking at Doug's headers. They are quite a bit cheaper than TTI especially since there is a discount at autozone right now. Are there any other headers that fit and won't drag on the ground?
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Re: Cam selection; 340 with manifolds
[Re: ScottSmith_Harms]
#2219417
12/23/16 01:49 AM
12/23/16 01:49 AM
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Joined: May 2005
Posts: 2,628 Middle TN
da50r
master
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master
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Middle TN
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You don't need headers to make power. Will you (usually) make more power with headers and exhaust? Yes. Do you need the difference? In street driving, usually not. I have one of each, both are stroker 340's, 422 and 426 cubes respectively. Both are built very similarly, similar cams ported iron heads that flow at around 280, both in 71 A-body cars with manual transmissions and 3,91 gears. Both have both been dyno'd so I have real data on them. The 426 cam specs are attached, the 422 was a very similar grind. The 426 made 450hp and 500tq. These numbers were made with exhaust manifolds, stock iron intake, stock Thermoquad carb, and everything else externally stock down to the belts and hoses. Now, the 422. It has TTI headers, mandrel bent 3" exhaust, a single plane intake, a Holly 950HP carb, 7AL ignition, and all the other 10 cent tricks. It made 530hp and 520tq on the dyno.
So, bottom line, A LOT of $ and optional equipment (as a package that works well together) resulted in roughly 75hp and 20lbs of tq most things being equal if not at least similar.
On the street you simply don't need the extra hp. the 450 engine will blaze the tires at any speed and torque is so close it feels the same.
.02 I am building a mild 360 now for a daily Duster.. well nice days but to drive it a lot. 4 speed. 3.55 gears. I am really really wanting to use manifolds. I hate headers for street cars. Care to shine some light on which manifolds? With a mild cam, rpm performer intake, and smog 360 heads, think 325 hp is possible on pump gas?
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Re: Cam selection; 340 with manifolds
[Re: da50r]
#2219471
12/23/16 09:32 AM
12/23/16 09:32 AM
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Joined: Jan 2003
Posts: 727 Ottawa, ontario
dd340
OP
super stock
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OP
super stock
Joined: Jan 2003
Posts: 727
Ottawa, ontario
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You don't need headers to make power. Will you (usually) make more power with headers and exhaust? Yes. Do you need the difference? In street driving, usually not. I have one of each, both are stroker 340's, 422 and 426 cubes respectively. Both are built very similarly, similar cams ported iron heads that flow at around 280, both in 71 A-body cars with manual transmissions and 3,91 gears. Both have both been dyno'd so I have real data on them. The 426 cam specs are attached, the 422 was a very similar grind. The 426 made 450hp and 500tq. These numbers were made with exhaust manifolds, stock iron intake, stock Thermoquad carb, and everything else externally stock down to the belts and hoses. Now, the 422. It has TTI headers, mandrel bent 3" exhaust, a single plane intake, a Holly 950HP carb, 7AL ignition, and all the other 10 cent tricks. It made 530hp and 520tq on the dyno.
So, bottom line, A LOT of $ and optional equipment (as a package that works well together) resulted in roughly 75hp and 20lbs of tq most things being equal if not at least similar.
On the street you simply don't need the extra hp. the 450 engine will blaze the tires at any speed and torque is so close it feels the same.
.02 I am building a mild 360 now for a daily Duster.. well nice days but to drive it a lot. 4 speed. 3.55 gears. I am really really wanting to use manifolds. I hate headers for street cars. Care to shine some light on which manifolds? With a mild cam, rpm performer intake, and smog 360 heads, think 325 hp is possible on pump gas? Pretty much any manifolds will work up to 325hp. My set up uses the 68-70 340 manifolds but you could use pretty much any 340-360 manifolds. My set up is good for about 325hp and is very mild Around 10.0 compression Edelbrock dual plane intake, go with an air gap if you can find one Stock 2.02 valve heads 600 cfm edelbrock carb or even a carter avs should work 220 @.050 duration .460 lift cam from racer brown That is all it should take for a 360 to put out an easy 325 hp and still be really mild and get decent gas mileage too. I have gotten around 18 mpg on a highway drive with 3.23 gears I also balanced my rotating assembly and made sure the block was machined properly. Good ring seal is important.
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Re: Cam selection; 340 with manifolds
[Re: da50r]
#2219472
12/23/16 09:38 AM
12/23/16 09:38 AM
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Joined: Feb 2005
Posts: 4,333 Prospect, PA
BSB67
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master
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Posts: 4,333
Prospect, PA
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With a mild cam, rpm performer intake, and smog 360 heads, think 325 hp is possible on pump gas?
.9 to 1.0 hp/cuin is pretty easy. You don't need anything exotic, but good parts and an eye to the details matter.
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Re: Cam selection; 340 with manifolds
[Re: dd340]
#2219560
12/23/16 01:20 PM
12/23/16 01:20 PM
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Joined: Jan 2003
Posts: 10,090 Frostbitefalls MN (Rocky&Bullw...
gregsdart
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Research how well your current mufflers flow, to see if they match the pipe dimensions. The book How to Build Horsepower, second edition, has a ton of info on exhaust systems and getting the most out of them. If your current mufflers are restrictive, you can figure out roughly what a change is worth based on how good the rest of your system is, and how much the mufflers are choking the system. To get the flow increase you want you might need to use reducers to go bigger on the entry/exit of the muffler you want to go to to get extra flow. My next move would be a GOOD converter, after that, posi, plus suspension tricks to get some weight transfer. since you want a decent lockup at cruise based on your comments. I am not sure how much can be done to get the manners you want plus a good stall increase, but a conversation with a couple of top converter builders ought to give you something to go on. A good converter is worth more ET than a gear change, and a stroker would really pick up the 60 ft with just a better converter and posi plus good tires, if you really want to turn up the wick.
Last edited by gregsdart; 12/23/16 01:24 PM.
8.582, 160.18 mph best, 2905 lbs 549, indy 572-13, alky
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Re: Cam selection; 340 with manifolds
[Re: dd340]
#2219738
12/23/16 05:56 PM
12/23/16 05:56 PM
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Joined: Jan 2003
Posts: 14,539 So. Burlington, Vt.
fast68plymouth
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I Live Here
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So. Burlington, Vt.
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10:1 .030 over 340, 587 heads with 2.02 valves and minor bowl blend, Performer manifold, Holley 650dp, Comp 268h cam, Mancini 1.5 roller rockers, 1 5/8" x 3" headers.
68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123 Dealer for Comp Cams/Indy Heads
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Re: Cam selection; 340 with manifolds
[Re: ScottSmith_Harms]
#2220922
12/26/16 12:38 AM
12/26/16 12:38 AM
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Joined: Jan 2003
Posts: 727 Ottawa, ontario
dd340
OP
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OP
super stock
Joined: Jan 2003
Posts: 727
Ottawa, ontario
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Yea, my point about pushing a stroker is two fold, nothing beats torque around town no matter how much peak HP your engine makes, and I've yet to hear anyone say: "I sure wish I would have just built a stock stroke engine" after driving a stroker I hear you on that. I have a stroker 416 in my 87 ram and with 4:10 gears it is literally impossible to get to full throttle in first or 2nd gear without putting it sideways. Although admittedly the tires are pretty useless and I should have drag radials on it.
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Re: Cam selection; 340 with manifolds
[Re: cdp]
#2221588
12/27/16 01:41 PM
12/27/16 01:41 PM
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Joined: Jan 2003
Posts: 14,539 So. Burlington, Vt.
fast68plymouth
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I Live Here
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So. Burlington, Vt.
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I'd think a well tuned, nearly stock 340 would be around 350 ponies. In 2001 Dulcich dynoed a stock 340 at Westech. With an Edelbrock 800 carb it made around 315hp. With headers it made like 330hp. Shortly after the 2003 Engine Masters competition it was discovered why the results from the Westech dyno always seemed so "good". The barometer was way off which caused the computer to spit out corrected numbers that were 5% high(if you do a search you can find info about this). So, take 5% off the 315hp exhaust manifold test and you're at 299hp, 5% off the 330hp header test and you're at 313hp. And those are with the 800cfm carb, so you'd be down even farther with a correct 340AVS on the motor. I seriously doubt there is going to be 50+hp found by "tuning".
68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123 Dealer for Comp Cams/Indy Heads
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