Building a 408 stroker
75dart said
I wasnt sure how big I should go with the cam because i want it streetable but still be able to take it to the strip.
IMO, What I would use with your combo would be the Comp Cams XE274H. This cam should provided monster torque and decent hi RPM power. Within the cams (& heads) limits. You should be able to drive anywhere at anytime with great low speed torque and enuff power on tap to really get you going well.
More bable;
Heres the thing on the converter. If you had a 2000 stall, the cams would be in a bracket size of , lets just say for/in example; 210 - 220 degress of duration @ .050. Putting in a bigger cam, lets just say the extreme other end, 260-270 degress @ .050 would not work great because the converter would not have enuff stall to allow the engine to reach where the cam starts to make power and it would make the car a slug down low. Tire size has an effect to a small degree unless the combo is really out of wack.
That takes care of duration. Now how much lift can the heads support? Also how well the ports are balanced. Thats also key in getting a cam zeroed in. As well as how much clearance you have in the piston. But since you don't have heads, the sky is still open. What I'll do is recomend a few Crane & Comp Cams that will work well in the basic combo info provided. More lift is possible with some of these cams or you can order a custom ground cam for basicly the same price, a few pennys more. These are just examples of what could be used.
An example of cam(s) that you could use would be;
Not great to good balance in the heads,
Low rpm side, XE 274 H
HIgher rpm XE 284 H or Lunati's 304A3LUN 231-239 @ .050 .514 .536 lift.
If you know that the heads flow well with higher lifts;
low, XE 275 HL
Higher, XE 285 HL
A better balanced head can also use a singal pattern cam, though most prefur dual no matter what. An example wold be a Comp Magnum cam like there 292H (high side) or the 280H (low side) or a Crane 232 @.050 with .504 lift. Luntia has a 235 @ .050 with .507 lift (PN 07402)
All would work well with the 3.91 you wanted to use. Notice how there all aroundthe same area of duration.
Also, being the engine is stroked larger, a larger engine tends to swallow up a large cam. The cam seems smaller due to engine size.
I like the XE 274H for stock ported heads that do not have a ton of work in them. If I had heads that had a lot of work, extensive porting and high flow numbers, the XE275HL I'd go after.
My 360 4spd car has 4.10's and a 27 inch tire. I like a heavier cam in a 4spd. (Personal taste) and would go with the XE285HL with my ported heads.
Sorry for the run on babble.