I have a 400 sbc that has the following mods and I would like opinions on the horsepower / torque ratings and at rpms if possible. Any information is much appreciated.

The 400 has been bored 0.040"
5.56 rods
991 heads, pocket ported, and valves are 2.02 / 1.60 (74.5 to 75 cc??)
XE262 cam with 114 lsa - 218 / 224 @0.05 and lift is .464/.470 (38 deg overlap)
pistons are (-12.5cc)
compression supposedly 9.1 to 1
hooker 2055's with single 3" exhaust
using computer controlled q-jet with DR (or CE) secondary rods
Hypertech thermomaster chip
Car has cat converter (3" high flow) and is emissions legal with air

 

That cam is really small for big cubic inches. If you want a guess, I'd say around 300 hp but that may be high.

If you want to know HP and torque at all rpm ranges, put the engine on a dyno.

 

Horrible heads, too.

I assume you need to keep it down to a Performer EGR intake, so you'll need to keep the cam from being too big; but you should be able to handle an XE268 with a 400.

Rethink the cam & heads.

 

The engine will pull at least 400 lbs of torque on low end. I doubt it would rev past 5,000 and still have power. with some good heads it would be a great stump puller or daily driver.... good vacuum and mileage. I would leave that cam in. It will have a hard takeoff, but not a high enough power band for drag racing. Great for sitting next to a mustang at a stoplight though....

 

i am a freak for porting and polishing but with 75cc?? heads your not going to see the performance you really want i learned this the hard way with my heads on my camaro. its not a great cam but anything better than stock so what can i say. if u ever wanna change for some real power try comps 268h to up your band and also be able to keep stock valve assembly if not crane's z-cam (the 1500-6000 rpm i forget the grind lift ect.) is a mean streetable cam but i wouldnt keep stock rockers springs or lifters with that... as it is the engine it self might be around 360horse? and round 400lbs.. but at the wheels depending on your gears i doubt you will see more than 300 especialy if your on stock v8 gears