While working on my sons car I have also been slowly building the engine for my car. I have been building a 427 stroker with a Price Dual four barrel set up with 600CFM carbs. The question I have has to do with the heads. Currently this is the short block that is built. 351W stroked to a 427 with a 4.17 Stroke Hawk Nodular Cast Iron Crank, 6.125 4340 I beam rods, Keith Black Pistons at 10.1 with stock heads, Solid Lift Mechanical Cam 294-302, 564-588, 230 duration at .050 and a bottom end crank stud girdle. The heads I currently have I bought used and are World Products Windsor SR heads with 52.5 cc Chambers, 2.05 Instake Valves, 1.65 Exhaust Valves and have been angled milled 5 degrees and offset .050. This was supposably done to unshroud the intake valves some to allow it to breath better. These will require me to mill the intake to match which I am not sure I really want to do that to the intake. I also know that these heads will drive my compression up quite a bit. I am also thinking I would have to severly retard the timing to get it to run properly on pump gas. My questions are, will this set up be street friendly? Would I be better off just getting a good set of aluminum heads instead, if so which ones would be best. How would you guys finish off the top end of the motor. An last what kind of horse power do you think this assembly will make? Any kind of input, good or bad would be greatly appreciated. Any ideas/suggestions would be greatly appreciated. I am sort of stuck on which way I should go at this point. I plan to back this unit with a TKO 600 5 speed manaul trans and 9" posi unit with 4:10 gears. The car will be mostly street driven with a little track action fo fun only. nothing seroius. Thanks for your input in advance. Allen Small
If its a street car, then build it for pump gas. Probably want to keep the compression ratio at 11.0 or under. sounds like those heads will be too high. When you say the Keith black pistons are 10:1 with stock heads, which stock heads are you referring too? chamber size? Also I dont like the idea of milling the intake, just incase you want or need to swap it out later then you have to mill another one.
Not knowing what fuels are avalible. Maybe e-85 might be a option What kinda lobe seperation is the cam on?
Ryan, The stock heads would be a 70 model 351W heads. I forget what the chamber size of them are. Your comment about milling the intake is the thought I had also. I am not set on using the World Products heads. I am just not sure what would be a good head to use with this set up to get the most out of it and it still be streetable and pump gas friendly. It would not bother me to have to run octane booster with the fuel if I decided to take it to the track. I am looking for suggestions as to what aluminum head set up would be the best (chamber cc?, intake valve size, exhaust valve size?) and what rocker arms (1.6 or 1.7) to use with them. The World Product heads also require a custom push rod length, which I have the set up for put and I would perfer to use a stock push rod set up if possible. I think this would just make things easier if I needed to replace any parts later. Thanks for your input! Allen Small
Russ, I am not sure what the lobe separtion is on the cam. I would have to check with the guy who built the short block for me then let you know. I have the box the cam came in I will also check that to see if it has any more info. Thanks Allen Small
Hi Allen, I would recommend these: http://www.airflowresearch.com/index.php?cPath=21_105 or these: http://www.airflowresearch.com/index.php?cPath=21_104
I will say this if the cam has a lobe seperation of 108-110*with it being a solid cam id guess it is in this range. Your cam will bleed off alot of low end cylinder pressure and that helps octane tolerance. I would probly try it out as is on 93 i ran my near 12.1 306 on 93 with iron heads and 30* of total timing again cam comes into play detonation isn't just a effect of compression but of the whole package and tuning.
detonation And it will occure without your're hearing it, doing damage all the way. Hot starts in July, etc would be a consideration. I believe you'd be happier with a combo thats designed to perform on 92 octane instead of over building and retarding the timing to compensate. jmo
After reading everyone comments and the issue with having to mill the intake 5 degrees to match the heads. I have decided not to use them on this motor. I will either sell them off or just set on them for another motor build for another car. I will start looking into a good set of off the shelf aluminum heads for this motor. I want to keep the compresion at 10:1 as it is set up for which would run fine on 93 octane fuel. Thanks for everyones input. Now just to figure out which heads would be best. bmcdaniel (Barry) suggested a set that I might look into, the AFR #220 58CC chamber heads. Let me know your thoughts on those. The larger chambers should keep my compresion where I want it and the valves are not that much different than what I have currently. It also indicates that these heads were designed for use on a 427 stroker. With these heads and the short block assembly above. What would you guys guess the horse power range might be for this set up. Again thanks for all of your input. Allen Small
How set are you on using your current cam? Normally you choose heads and intake first and spec the cam to get the the heads, intake, and short block to work together. Maybe what you have will be ok, maybe it'll leave something on the table.
Barry, I am not dead set on the cam . It is the cam that came with the motor. I bought the short block from a guy who was building it then abonded the build because the class he was racing in banned these type motors. I got the whole assembly with no heads, just the short block assembled for $1,400.00 which I thought was a good deal. The heads I have, I bought of another person and at the time thought they would work for what I have which they will but just will not be very streetable due to gas octane levels that are available around here. But I am really having second thoughts now about the 5 degree milling of the intake required. I really do not think I want to do that to the dual four barrel intake. If I ever decided to change I would have a hard time selling the intake set up because of that and if I but another intake on I would have to have it milled also. Seems now to be just to much trouble for what I would get out of these heads. I could actually put these heads on the short block assembly I bought from you a few years ago and possibly have a good combo now that I think about it. Allen Small
