Carburetor cfm calculator

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318willrun said:
Page 4 ... you lost me back about 3 stop lights ago, you turned left? Opening post, we were talk'n 360? I read this ^^^ this morning, and we are working with a stock 318 2bbl? Ok, whatever it is that you are trying to do for whatever car, just get an eddy performer intake with a 600 eddy carb and electric choke. That should cover all the basis even if by the time I catch up and were talk'n 383 in a C - body !!! LOL Good luck !
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My bad, I'm looking at 2 different cars, one's a 318 other a 360.
 
RustyRatRod said:
The Performer intake isn't totally worthless. It's a bit better than stock and aluminum, too. I've seen some on 11 second cars. lol For a stock to relatively moderate build, they're a good choice. If I didn't have an intake at all, I'd honestly probably look for something different, but if I had one, I wouldn't go out of my way to replace it.
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Has stock 2 barrel. Would I be better off buying a performer rpm rather than the performer? It's going to be a mild build, cam probably have a duration of 224*max. Is 9.5 enough compression
 
Dan the man said:
Has stock 2 barrel. Would I be better off buying a performer rpm rather than the performer? It's going to be a mild build, cam probably have a duration of 224*max. Is 9.5 enough compression
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Dan, forgive me for not wanting to back read. Is this a 318 or 360?
 
Dan the man said:
I understand, it's the 318.
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Ok, if you stay with the 318 heads...and there's nothing wrong with that, you'll not want anything real crazy, so yeah, I think the Performer should be in the running. Also, the LD4B, which is an older Edelbrock intake. REALLY good performing intake, beats the Performer by a good bit. If you can find one without having to hack off a leg, I would recommend that. Also another good choice, IMO is the Holley Street Dominator. Even though it's a single plane intake and it has bigger ports, it's kinda a special piece in that it loses nothing on the bottom end and pulls like snot in the mid range and on top. I would only use it though, if you go much more than "stockish" if that makes sense.

I looked on ebay and the USED Performers are going for like 250-300 or more. That's dumb **** money for a used intake. Maybe put a want ad in the classified section and see if a member might help you out.
 
Dan the man said:
I'm sure that most on here know what I'm wanting to do with the car I get. From what I've read, if I go from a 2 barrel to a 4 barrel that the edelbrock performer intake wouldn't be worth the effort. Also, the rpm's that my engine would be operating in most of the time wouldn't a 600 cfm be plenty for a 318? Cylinder heads, doesn't the smaller ports make good power in the low to midrange area? Would cylinder heads with 170cc intake runner's be to big for a mild 318 or are they okay? Cam, single or dual pattern grind? I'm wanting good throttle response and acceleration with good torque in the low to midrange. I'm not worried about doing major upgrades later as I'm 62 years old and don't care about racing anymore. I'm wanting a cruiser that's fun to drive and has a little extra zip. When I first said that it's a budget build, I do have amount planned for the car and engine modifications, gears, and a good exhaust system. If the cylinder heads wouldn't be cost effective to get them redone, then what would be a good choice for a set of heads? I figured that I could build a engine whether it's a 318 or a 360 to perform well from off idle to around 5,000 rpm's. I appreciate all the help, advice etc, but I truly don't think that I need tunnel ram or a blower to reach my goal.
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I see you don't care about racing but obviously you want the car to be faster than a stock 318, what power or if you were to take it to the track it E.T. you would like it to do? EG like most modern sedans can do around 15 in the quarter mile so obviously that's what the public want's in there family car. I'm guessing you'd be happy with a low 14 maybe high 13 ? So like 275-325 hp ?

So when picking a head more important than port size is will it reach your hp goals with reasonable cam and cr eg.. stock 318 heads can do about 300 without porting if you went 1.88 360 or port 318 heads you could go smaller cam to reach same aka more streetable or go up in power with same cam., but even before that is where do you want to make power? Sounds like to me idle-5000 rpm so that's 0.9-1 to 1 hp per cid so for a 323 would be 291-323 hp, if your looking for more hp need more displacement or if want power to be made lower rpm.

Here a stock long block low cr 318 making 282 hp with cam 4bbl and headers

318 Long Block Bolt Ons - Tech Articles - Mopar Muscle Magazine

bump up cr you got 300 hp, port or 360 heads your hitting 1:1 hp:cid better heads you could still make 323 hp but with smaller cam etc..
 
RustyRatRod said:
Ok, if you stay with the 318 heads...and there's nothing wrong with that, you'll not want anything real crazy, so yeah, I think the Performer should be in the running. Also, the LD4B, which is an older Edelbrock intake. REALLY good performing intake, beats the Performer by a good bit. If you can find one without having to hack off a leg, I would recommend that. Also another good choice, IMO is the Holley Street Dominator. Even though it's a single plane intake and it has bigger ports, it's kinda a special piece in that it loses nothing on the bottom end and pulls like snot in the mid range and on top. I would only use it though, if you go much more than "stockish" if that makes sense.

I looked on ebay and the USED Performers are going for like 250-300 or more. That's dumb **** money for a used intake. Maybe put a want ad in the classified section and see if a member might help you out.
Click to expand...
What cam would you recommend?
 
Dan the man said:
I'm sure that most on here know what I'm wanting to do with the car I get. From what I've read, if I go from a 2 barrel to a 4 barrel that the edelbrock performer intake wouldn't be worth the effort. Also, the rpm's that my engine would be operating in most of the time wouldn't a 600 cfm be plenty for a 318? Cylinder heads, doesn't the smaller ports make good power in the low to midrange area? Would cylinder heads with 170cc intake runner's be to big for a mild 318 or are they okay? Cam, single or dual pattern grind? I'm wanting good throttle response and acceleration with good torque in the low to midrange. I'm not worried about doing major upgrades later as I'm 62 years old and don't care about racing anymore. I'm wanting a cruiser that's fun to drive and has a little extra zip. When I first said that it's a budget build, I do have amount planned for the car and engine modifications, gears, and a good exhaust system. If the cylinder heads wouldn't be cost effective to get them redone, then what would be a good choice for a set of heads? I figured that I could build a engine whether it's a 318 or a 360 to perform well from off idle to around 5,000 rpm's. I appreciate all the help, advice etc, but I truly don't think that I need tunnel ram or a blower to reach my goal.
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Also it's hard to improve idle - 2500 rpm a bump in cr will but for the most part makes what it gonna make there Cubic inch is the only real way to improve the power in that range, other than that best you can to is pick part that don't overly effect it there will give you more power in the 2500- 5000 rpm.
 
Dan the man said:
Has stock 2 barrel. Would I be better off buying a performer rpm rather than the performer? It's going to be a mild build, cam probably have a duration of 224*max. Is 9.5 enough compression
Click to expand...
Is get a Performer, 600 AFB.
Is 9.5-1 enough, in general terms, probably so, but in actual…. It depends on the cams timing events.
What’s the gear ratio & are you willing to change it out? Are you willing to change the torque converter out?
 
rumblefish360 said:
Is get a Performer, 600 AFB.
Is 9.5-1 enough, in general terms, probably so, but in actual…. It depends on the cams timing events.
What’s the gear ratio & are you willing to change it out? Are you willing to change the torque converter out?
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Gear ratio, I think is 2.73's and I'm willing to change out both the gears and torque converter
 
Dan the man said:
Gear ratio, I think is 2.73's and I'm willing to change out both the gears and torque converter
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What are you willing to change them out to ? and what tire size makes a big difference to final ratio.
If you don't overly care what performance just do a 9:1 cr 600 cfm on a performer intake with say comp xe250h or similar cam decent headers with mild stall and 3.23-3.55 gears and call it a day.
 
RustyRatRod said:
Ok, if you stay with the 318 heads...and there's nothing wrong with that, you'll not want anything real crazy, so yeah, I think the Performer should be in the running. Also, the LD4B, which is an older Edelbrock intake. REALLY good performing intake, beats the Performer by a good bit. If you can find one without having to hack off a leg, I would recommend that. Also another good choice, IMO is the Holley Street Dominator. Even though it's a single plane intake and it has bigger ports, it's kinda a special piece in that it loses nothing on the bottom end and pulls like snot in the mid range and on top. I would only use it though, if you go much more than "stockish" if that makes sense.

I looked on ebay and the USED Performers are going for like 250-300 or more. That's dumb **** money for a used intake. Maybe put a want ad in the classified section and see if a member might help you out.
Click to expand...
273 said:
What are you willing to change them out to ? and what tire size makes a big difference to final ratio.
If you don't overly care what performance just do a 9:1 cr 600 cfm on a performer intake with say comp xe250h or similar cam decent headers with mild stall and 3.23-3.55 gears and call it a day.
Click to expand...
That's kinda what I'm looking at doing. Would the 3.55's give the best bang for the buck and what would be the correct tire size for the 3.55 gear ratio?
 
273 said:
What are you willing to change them out to ? and what tire size makes a big difference to final ratio.
If you don't overly care what performance just do a 9:1 cr 600 cfm on a performer intake with say comp xe250h or similar cam decent headers with mild stall and 3.23-3.55 gears and call it a day.
Click to expand...
If I was able to get a set of 302 heads, would it be worth my while in getting them and go with 1.88 intake and 1.600 exhaust valve's along with the other modifications you mentioned or just stay with the stock heads
 
Dan the man said:
That's kinda what I'm looking at doing. Would the 3.55's give the best bang for the buck and what would be the correct tire size for the 3.55 gear ratio?
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There's no correct tire size 26 in tires (245r 60 15) with 3.55 would be the same over all ratio as 28 in tires (275r 60 15) with 3.73.
 
Dan the man said:
If I was able to get a set of 302 heads, would it be worth my while in getting them and go with 1.88 intake and 1.600 exhaust valve's along with the other modifications you mentioned or just stay with the stock heads
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I'm guessing your not porting say the basic build 9:1 cr xe250h cam 600 cfm performer intake and headers, the heads you pick will effect your final hp output. so any 273/318 stock heads makes 250 hp, 1.88 360 heads might get you 280 hp, magnums heads 300 hp, speedmaster or eddy heads 325+ hp etc... those obviously guesstimation. I'd go with speed master if you have the money, best dollar to performance ratio and it's hard to justify putting money into stock heads.
 
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Don't discount the holley spread bore DP. I came upon one for $20. Bolted it up to my 340 with a Strip Dominator intake and it blew away my Edel 750. Ended up giving that edel to my friend. Tiny primaries, huge secondaries ala TQ but with full secondary control at the pedal, no air doors. Idled like an easy chair too. Cant remember what I did with that jem, I think I sold it to finance my dual 390's then onto a 650 Demon (mistake!). EFI from then on
 
273 said:
What are you willing to change them out to ? and what tire size makes a big difference to final ratio.
If you don't overly care what performance just do a 9:1 cr 600 cfm on a performer intake with say comp xe250h or similar cam decent headers with mild stall and 3.23-3.55 gears and call it a day.
Click to expand...
No converter change needed with that broom stick!
 
I started checking into the cost of doing this build, a new performer intake for the sbm's is $363. I'm not paying almost $400 for a intake manifold, not going to happen. I'll wait till spring when swap meets open up.
 
Dan the man said:
I started checking into the cost of doing this build, a new performer intake for the sbm's is $363. I'm not paying almost $400 for a intake manifold, not going to happen. I'll wait till spring when swap meets open up.
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I got your back on that one! Especially for the Performer? It's a decent intake but puhhlleezzzz. No way. You can find something reasonable if you hold out.
 
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