So i posted a topic about comparing two cams but i have been doing a little reading around. I have a 305 that has apparently been bored and i put a stroker crank in it. Dont really remember the stroke of it. On top it has a holley 600cfm with a weiand street warrior intake. Ported and polished 416 castng heads. And behind it has a completely stock 700r4 stock converter with 3.42 gears behind that. What cam would you reccomend for a street car? I'd love off the line and be able to break the tires loose with my brand new posi. It wont do it now. The cam in it doesnt really kick in until 2,000rpm and i really dont care for that. Thanks in advance! Also, i'd love a slightly lumpy idle but it isnt a necessity. I'd rather have a sleeper than a loud obnoxious car that has no power on the track. this is also my daily driver and when summer comes, probably hit the track every other weekend or so. Thanks
cam recommendation
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Regardless of cam I really dont think you are gonna get much torque from a 305. Most 305 builds acknowledge this and they end up higher in the rpms in order to get the power from them. A good running 350 will put you miles ahead of a cam swap, break the tires loose easily, and then you can build from that for even more power. I hate to be that guy to say swap in a 350 but come on man there's no down side to it 
You got a 350 to donate? Lol. Its kinda hard to buy a somewhat good starter for a build being in high school and driving 20 miles everyday for work to buy a new motor. I bought a 600cfm carb and plan to sell my nice holley 3310 for $175 and then buy a cam for it.-83MONTESS- said:Regardless of cam I really dont think you are gonna get much torque from a 305. Most 305 builds acknowledge this and they end up higher in the rpms in order to get the power from them. A good running 350 will put you miles ahead of a cam swap, break the tires loose easily, and then you can build from that for even more power. I hate to be that guy to say swap in a 350 but come on man there's no down side to it
I dont have one but if you save your money instead of trying to polish that turd of a 305 you could get yourself a decent 350 :lol: Hell I was looking for 350s when my 305 blew up and ending up finding a 400, then when looking for another 400 to build in class I found a 454! So just stay patient and keep looking and you will trip over a deal. The only parts I would be buying would be bolt on parts like headers, intake, etc that way it all works on the 350. Good luck in your search!79cutlasssalon442 said:You got a 350 to donate? Lol. Its kinda hard to buy a somewhat good starter for a build being in high school and driving 20 miles everyday for work to buy a new motor. I bought a 600cfm carb and plan to sell my nice holley 3310 for $175 and then buy a cam for it.-83MONTESS- said:Regardless of cam I really dont think you are gonna get much torque from a 305. Most 305 builds acknowledge this and they end up higher in the rpms in order to get the power from them. A good running 350 will put you miles ahead of a cam swap, break the tires loose easily, and then you can build from that for even more power. I hate to be that guy to say swap in a 350 but come on man there's no down side to it
Garbage in garbage out.
The cam is fairly important piece of the puzzle so we need to know some critical info if you want a decent answer. It sounds like youre unsure about what is actually in your engine. The compression ratio, current cam, converter, rear gears, headers, intake and carb are all important factors in choosing a cam. I read your other thread, and it bothers me that you say the engine has "lots of power" up top, but wont even chirp the tires off the line. Something wrong there. Noted that you have a stock converter, and 3.42 gears.
Before you spend a dime, is your engine in sound running condition? No vacuum leaks? Compression tested and all cylinders within 10%? Smooth idle, and carburetor dialed in? Turne-up stuff up to date? etc etc.... What is the timing set at? If your cam is big one, it will want LOTS of initial advance. So if your cam is in the 3000+ to 6500rpm range, and you have less than 20* of timing, then thats your issue.
It sounds like you;re on the right track with the two cams you picked. I try to pick an RPM range, and then choose one with the absolute highest lift possible. But your heads, intake and exhaust need to be up to the task as well.
That being said, dont expect much of a gain simply with a cam swap. It sounds like youre expecting the powerband to be moved down, and thats the right attitude to have in mind.
The cam is fairly important piece of the puzzle so we need to know some critical info if you want a decent answer. It sounds like youre unsure about what is actually in your engine. The compression ratio, current cam, converter, rear gears, headers, intake and carb are all important factors in choosing a cam. I read your other thread, and it bothers me that you say the engine has "lots of power" up top, but wont even chirp the tires off the line. Something wrong there. Noted that you have a stock converter, and 3.42 gears.
Before you spend a dime, is your engine in sound running condition? No vacuum leaks? Compression tested and all cylinders within 10%? Smooth idle, and carburetor dialed in? Turne-up stuff up to date? etc etc.... What is the timing set at? If your cam is big one, it will want LOTS of initial advance. So if your cam is in the 3000+ to 6500rpm range, and you have less than 20* of timing, then thats your issue.
It sounds like you;re on the right track with the two cams you picked. I try to pick an RPM range, and then choose one with the absolute highest lift possible. But your heads, intake and exhaust need to be up to the task as well.
That being said, dont expect much of a gain simply with a cam swap. It sounds like youre expecting the powerband to be moved down, and thats the right attitude to have in mind.
I know it has 12* of timing at idle but under load it pings like crazy. And i also think the carb is the problem. Its a 750. I think it's too much. I ordered a nice 600 off ebay to try to see if that gets me more throttle response. And yeah, the motor runs good. The guy we bought it from built it like 15 years ago when he was in racing school and then it sat in a storage unit. Im not sure how to keep up the timing but not let it detonate. The Timing has been probably the most pain of this motor. Except for the spun bearing when we bought it. Lolonline170 said:
750 is a bit much but it shouldnt matter. You could tune a 1050 dominator on there too, and it would still work good. The 600 is a good move, but it isnt the problem for the moment. You can figure out your issue with the 750 on there.
Again, "motor runs good" and "built 15 years ago in racing school" doesnt mean jack. Spun a bearing? Without a compression test or anything quantify, it doesnt mean much. If there is a problem, you wont know about it. Throwing parts at it can get expensive if you dont know the problem.
If the cam is as big as you think it is, it will want 20*+ at idle. Do you know what cam is in it now? If it pings up top, disconnect your vacuum advance for starters, and throw some high octane fuel in the tank like 91 or 95 and see how it does.
One sure fire way to eliminate all doubts about the timing, is to lock it out for testing purposes. Disconnect the vacuum advance, find a way to lock out the distributor. Start the car, and set the timing to 32*. Try a couple of WOT runs up to about 5000rpm and see if the tires now chirp off the line. At 32* it should not ping up top at all. It may ping slightly off the line. With the timing locked out at a certain RPM, you KNOW its not moving around, and its a great way to figure out what your car likes.
I did this on my 350 with a comp cams 284-H years ago. I found out it liked to idle at 24*, and it wanted all the timing in by 2800rpm. It loved 36* up to 5200rpm, then it wanted 34* for top end horse power. I locked out the distributor with a piece of a locking latch I found around the house. I ground off the corners,. drilled a couple of holes, and used GOOP adhesive to lock it in place. DO NOT USE ZIPTIES!
Again, "motor runs good" and "built 15 years ago in racing school" doesnt mean jack. Spun a bearing? Without a compression test or anything quantify, it doesnt mean much. If there is a problem, you wont know about it. Throwing parts at it can get expensive if you dont know the problem.
If the cam is as big as you think it is, it will want 20*+ at idle. Do you know what cam is in it now? If it pings up top, disconnect your vacuum advance for starters, and throw some high octane fuel in the tank like 91 or 95 and see how it does.
One sure fire way to eliminate all doubts about the timing, is to lock it out for testing purposes. Disconnect the vacuum advance, find a way to lock out the distributor. Start the car, and set the timing to 32*. Try a couple of WOT runs up to about 5000rpm and see if the tires now chirp off the line. At 32* it should not ping up top at all. It may ping slightly off the line. With the timing locked out at a certain RPM, you KNOW its not moving around, and its a great way to figure out what your car likes.
I did this on my 350 with a comp cams 284-H years ago. I found out it liked to idle at 24*, and it wanted all the timing in by 2800rpm. It loved 36* up to 5200rpm, then it wanted 34* for top end horse power. I locked out the distributor with a piece of a locking latch I found around the house. I ground off the corners,. drilled a couple of holes, and used GOOP adhesive to lock it in place. DO NOT USE ZIPTIES!
I really hate to sound stupid. But 1.) What do you mean "lock out" the distributor? How do i do that? And how do you measure timing up that high? My tab goes to 12*online170 said:
No not stupid at all. By the way, my suggestions seem harsh, but they are all FREE. So try them. Back in high school, spending $$$ on a cam was a big deal. So if you can fix you prob for free, then that would be awesome.
Im trying to find you a pic of how i did mine.
So you have a couple of advance mechanisms inside the distributor.
1) Vaccum advance. You can disable it by disconnecting the vacum line. You can lock out by getting a small plastic piece made by mr gasket I think. Ill post a link in a bit. Disabling this one works fine.
2) Mechanical advance. This is the two counter weights, the center linkage and springs under the rotor. You want to take note of how they are installed. Remove them. You will notice the rotor now moves freely. SO you want to lock this in one position so the timing doesnt float. Hope that makes sense. Let me find you a pic so you see what i mean. The easiest way is to have a small metal plate witha slot or 4 holes drilled in it. Line up the 4 "posts" that the springs clip onto, and slide the plate over top so they dont move.; This is fully advanced position. Thats how i did mine.
Measuring timing, there are a couple of ways. Best is to use a dial back timing light. This allows you to set the timing on the light. So you keep dialing back the number until you indicator lines up, and thats your timing.
Taken from another forum;
The poor man's method. Use some tape on the balancer and mark it according to the text below.
How do you find 36deg on your harmonic balancer?
36degress is 1/10th around the diameter of the balancer. Wrap a piece of masking tape around the balancer marking it where it meets the TDC mark.
remove the tape and measure the length between the two marks you made.
that length divided by 10 is the length from TDC to 36deg BTDC on the balancer. Mark the tape at the 1/10th length along the tape and reinstall it on the balancer aligning your tdc marks as before. mark the balancer for 36deg BTDC. Now you can set your timing at 36deg BTDC.
Im trying to find you a pic of how i did mine.
So you have a couple of advance mechanisms inside the distributor.
1) Vaccum advance. You can disable it by disconnecting the vacum line. You can lock out by getting a small plastic piece made by mr gasket I think. Ill post a link in a bit. Disabling this one works fine.
2) Mechanical advance. This is the two counter weights, the center linkage and springs under the rotor. You want to take note of how they are installed. Remove them. You will notice the rotor now moves freely. SO you want to lock this in one position so the timing doesnt float. Hope that makes sense. Let me find you a pic so you see what i mean. The easiest way is to have a small metal plate witha slot or 4 holes drilled in it. Line up the 4 "posts" that the springs clip onto, and slide the plate over top so they dont move.; This is fully advanced position. Thats how i did mine.
Measuring timing, there are a couple of ways. Best is to use a dial back timing light. This allows you to set the timing on the light. So you keep dialing back the number until you indicator lines up, and thats your timing.
Taken from another forum;
The poor man's method. Use some tape on the balancer and mark it according to the text below.
How do you find 36deg on your harmonic balancer?
36degress is 1/10th around the diameter of the balancer. Wrap a piece of masking tape around the balancer marking it where it meets the TDC mark.
remove the tape and measure the length between the two marks you made.
that length divided by 10 is the length from TDC to 36deg BTDC on the balancer. Mark the tape at the 1/10th length along the tape and reinstall it on the balancer aligning your tdc marks as before. mark the balancer for 36deg BTDC. Now you can set your timing at 36deg BTDC.
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