cam selection
5th Gear Member
Joined: Apr 2007
Posts: 2,100
From: Texas Hill Country
RE: cam selection
I have AFR 205s on my 383 and LOVE them. I know some people have complained about the quality, but mine are machined very nicely. Stock 351W heads are not going to flow well when compared to most any aftermarket head. Keep in mind that it is not all about flow but rather velocity and flow. If you get too large a ports, your velocity is going to bottom out and you will not get in any air. This is a popular link for checking out head flows.
http://users.erols.com/srweiss/tablehdc.htm#Ford
Grey, if 400hp is your goal, you need to tell us at what rpm you want to do this. 400Hp at 7000 is going to be easier than 400hp at 500. It is much easier to make horsepower at high rpms than at low rpms. It take displacment, compresion,and a lot of air tomake low end horsepower. So now we need to know how stout a bottom end and bolts you need to survive the rpms you are going to spin in order to achieve 400hp.
I know this is kinda confusing so fire back question on what you do not understand.
http://users.erols.com/srweiss/tablehdc.htm#Ford
Grey, if 400hp is your goal, you need to tell us at what rpm you want to do this. 400Hp at 7000 is going to be easier than 400hp at 500. It is much easier to make horsepower at high rpms than at low rpms. It take displacment, compresion,and a lot of air tomake low end horsepower. So now we need to know how stout a bottom end and bolts you need to survive the rpms you are going to spin in order to achieve 400hp.
I know this is kinda confusing so fire back question on what you do not understand.
Thread Starter
2nd Gear Member
Joined: Sep 2006
Posts: 197
From: California
RE: cam selection
I would like to make 400 hp around 6000 rpm. I was thinking about running 10:1 compression. Even though I am running a 289 and (possibly run stock 351 W heads, worked over) they wouldnt flow similar to aftermarket 289 heads? How much revs can a stock crankshaft take? I would def replace the rods/pistons/ etc.....
3rd Gear Member
Joined: Mar 2006
Posts: 971
From: Apison, TN
RE: cam selection
Stock crank can turn 5500 safely. 6000 is ok, but I wouldn't want it to stay there long. I guarantee you can not make 400 HP at 6000 RPMs on 351W heads and 10.0:1 compression. Sorry, not going to happen. I would say 400 HP at 7000 RPM would be a lot easier, but you are going to need a balanced bottom end with forged rods and 3/8 bolts. A forged crank would be a plus, but I don't think it is 100% necessary as long as its balanced. Also you will need at least hyperutectic pistons, but there again, forged ones wouldn't hurt. Heads/cam/intake/carb will all be critical decisions because these parts are the ones that will actually make your power. One more thing... have you considered stroking the engine? It would be a lot easier to reach your goal if you had more cubic inches.
Thread Starter
2nd Gear Member
Joined: Sep 2006
Posts: 197
From: California
RE: cam selection
Yea I was looking into the 331 stroker kit. I just figured that paying the machine shop to stroke my block would be an arm and a leg. And being in college I don't have a lot of money right now. Thats why I figured on just simple bolt ons. Anyone know how much a machine shop charges to stroke an engine (ballpark?)
3rd Gear Member
Joined: Mar 2006
Posts: 971
From: Apison, TN
RE: cam selection
Actually, stroking to a 331 requires no more work than building a 289 since you don't have to clearance the block for a 331. So, if you are going to buy a crank, rods, and pistons anyway, why not just go ahead and build the 331. It would cost about the same if not less for the parts, and the labor will be the same.
If you decide to go with a 331, just buy a kit from summit or jegs. You can get them for les than $1000, which is a smoking deal. DO NOT try to piece together a kit, you will end up spending a lot more money in the long run. As far as the labor, it varies from region to region. I would just call around and get estimates to build a "289." Tell them you will be supplying all new parts for the bottom end. In all reality, you could more than likely assemble the engine yourself. It really isn't hard if you have the correct tools. If not, paying them to do it shouldn't cost too much. The money will be more for the machine work they may(will) have to do.
Look around on ebay for some good used aluminum heads because even with a 331, 400 HP will be hard to reach with those heads. The fact is that they just don't flow all that much better than 289 heads. And most of them have large combustion chambers that will reduce your compression and hurt your power. Try to aim for at least 10:1 compression, but I like something around 10.5:1. After you get some good heads, call comp and get them to reccomend a cam for you. Just be sure you know the ins and outs of your car well because they are going to ask you a lot of questions. I would recommend a Performer RPM Air Gap intake from Edelbrock (or professional products makes one jsut like it for les money). These intakes whave a broad spectrum on what kind of engine they are suitable for (basically, it will work on a stock engine without hurting power, but will work on engines as big as a 347 and still flow well enough).I beleive you said you have a C4 auto transmission? If so you also may need to have it built to hold that power, and you will more than likely need a higher stall converter to work with the cam you will need to make your 400 mark. We see this stuff all the time... people think they can just throw in a cam and some different style heads and then haul a$$, but it just doesn't work that way unfortunately. You have to build the car to make that power. This includes engine, transmission, rearend (if your car was a V8 original then the current one can get you by for some time) and often times the brakes will need to be converted to disc so that you can stop (assuming this hasn't already be done). I am in college too, so I know how money is. But then again, I do ALL of my own work, so that saves a lot of labor money. Take your time, and shop around. Look for good deals. You can do this if its what you want, but be patient with it and the end result will be worth it.
If you decide to go with a 331, just buy a kit from summit or jegs. You can get them for les than $1000, which is a smoking deal. DO NOT try to piece together a kit, you will end up spending a lot more money in the long run. As far as the labor, it varies from region to region. I would just call around and get estimates to build a "289." Tell them you will be supplying all new parts for the bottom end. In all reality, you could more than likely assemble the engine yourself. It really isn't hard if you have the correct tools. If not, paying them to do it shouldn't cost too much. The money will be more for the machine work they may(will) have to do.
Look around on ebay for some good used aluminum heads because even with a 331, 400 HP will be hard to reach with those heads. The fact is that they just don't flow all that much better than 289 heads. And most of them have large combustion chambers that will reduce your compression and hurt your power. Try to aim for at least 10:1 compression, but I like something around 10.5:1. After you get some good heads, call comp and get them to reccomend a cam for you. Just be sure you know the ins and outs of your car well because they are going to ask you a lot of questions. I would recommend a Performer RPM Air Gap intake from Edelbrock (or professional products makes one jsut like it for les money). These intakes whave a broad spectrum on what kind of engine they are suitable for (basically, it will work on a stock engine without hurting power, but will work on engines as big as a 347 and still flow well enough).I beleive you said you have a C4 auto transmission? If so you also may need to have it built to hold that power, and you will more than likely need a higher stall converter to work with the cam you will need to make your 400 mark. We see this stuff all the time... people think they can just throw in a cam and some different style heads and then haul a$$, but it just doesn't work that way unfortunately. You have to build the car to make that power. This includes engine, transmission, rearend (if your car was a V8 original then the current one can get you by for some time) and often times the brakes will need to be converted to disc so that you can stop (assuming this hasn't already be done). I am in college too, so I know how money is. But then again, I do ALL of my own work, so that saves a lot of labor money. Take your time, and shop around. Look for good deals. You can do this if its what you want, but be patient with it and the end result will be worth it.
Thread Starter
2nd Gear Member
Joined: Sep 2006
Posts: 197
From: California
RE: cam selection
Thanks tyler72. I am glad to hear that no clearancing needs to be done to install the 331 stroker kit. Makes me feel a lot better about things. And with the way things have been going and my williness to work on projects that I have never done before, I should be able to save some money. Side note. My mustang is originally a v8 and came with the c4. I am thinking about swaping in the aod or a t5 so I can run better gears. Thanks for the advice.
6th Gear Member
Joined: Aug 2007
Posts: 5,896
From: Elk Grove, CA
RE: cam selection
Whoa whoa whoa...clearancing will depend on the stroker kit you decide to use. I did have to have my block clearanced for my 331 kit, because I'm using Scat forged rods which use cap screw rod bolts. Without clearancing, they would interfere with the cylinder skirts.
Not a big deal to get the block clearanced, though. Just tell the machine shop to do it while they have the block (you'll have to give them therotating assembly), that way it gets cleaned afterwards as well.
Not a big deal to get the block clearanced, though. Just tell the machine shop to do it while they have the block (you'll have to give them therotating assembly), that way it gets cleaned afterwards as well.