5.0 non H.O. questions on hp gains

[88VicSedan]

Ok well wanted to clearify i know what i need to do the H.O conversion for my '88 Crown Vic, i wanted to ask about the gt40p heads, i know a guy that has a rebuild set thats been milled i think he said .020, with the combo of the H.O components less e7 heads, and less intake manifold since i have upper lower cobra intake, i picked up 70mm throttle body and egr spacer, wanted to check with you guys and see what hp i would get out of the gt40p heads, t/b & cobra intake....i do have shorty header and 2.5" dual exhaust already...are we talking 15-20 hp maybe? Whats you senior guys input. I got all the parts pretty cheap...hp wise what would you guys say i'll get out of it?

[1980c10]

Your already so close why not shove a H.O. cam in there, and a H.O. ecu, with some orange top injectors. Also you could go ahead and do a mass air swap. But like I was saying. Why do all that work just to leave the junk lopo cam, injectors, and ecu in there? Why not just go ahead and finish off the H.O. conversion while you have it apart?

[88VicSedan]

Your already so close why not shove a H.O. cam in there, and a H.O. ecu, with some orange top injectors. Also you could go ahead and do a mass air swap. But like I was saying. Why do all that work just to leave the junk lopo cam, injectors, and ecu in there? Why not just go ahead and finish off the H.O. conversion while you have it apart?

yea that is definately the plan, i know i have to reset the plug wires for H.O. firing order, i just got a H.O. ecu and cam the other day, and already had the 19lb injectors...
i was just wondering with H.O. ecu, cam, injectors w/ cobra intake and gt40p head what my around about hp @ the wheels would be? I do have everything to do H.O. conversion, i should've went more in depth with my question. just wanting to see if anyone had round about idea how much more hp from cobra intake and gt40p heads in the H.O. combo would produce....didn't think about the mass conversion though...thanks

[1980c10]

I would guess if properly tuned you could see between 250-275 rwhp
I bone stock H.O. will usually put down about 190rwhp

[88VicSedan]

I would guess if properly tuned you could see between 250-275 rwhp
I bone stock H.O. will usually put down about 190rwhp

that sounds pretty good to me, theres a company local that specializes in tunes for Mustangs, So it shouldn't be a problem with conversion. thanks for your help

[1990LTD]

what's the mass air conversion that is see folks talk about often? I'm trying to read up more on engine building as well, and why different parts make more power, etc..I understand that bigger injectors = more fuel -> new ECU to control them so it's not just treating them like the stock injectors, and that a better intake (cobra, as mentioned previously), less restrictive heads (e7, gt40) and headers (mustang) make things flow better, and that the bigger injectors and ECU are required, but I am a little vague on the camshaft, and what makes one an improvement over the other, what is a "roller" camshaft, etc

[gadget73]

I'd guess a solid 30 hp over stock HO spec with those heads and intake, maybe a little more. I would suggest doing the clay thing to check your piston to valve clearance with those heads. Probably not a problem, but the stock pistons have no valve reliefs, so you'll want to be very sure its not all going to meet in the middle in an unhappy way.

The mass air thing is just a different means of monitoring air flow into the engine. Stock uses speed density, or what I like to call educated guess method. It monitors engine load by a vacuum (MAP) sensor, throttle position, air temperature, engine speed, and engine coolant temperature and plugs those into charts designed using stock engine airflow parameters to figure out how much air is moving through, then calculates fuel from that. Mass air just directly measures how much air is getting sucked into the intake, and takes that along with rpm, coolant, air, and throttle position to determine fuel. Its a bit more accurate, and it allows you to make changes to the engine, such as different cams, heads, etc and still have it run right. If you increase the airflow on an SD engine with better heads, bigger cam, etc the ECM has no way to know about that, so it just assumes you're running a stock motor and feeds you fuel accordingly.

Roller cam is just a different way of making the lobes. The lifters have wheels on them to ride on the cam. Flat tappet cams have a flat face on the lifter, and the lobe is made differently to deal with that. You can have a much sharper ramp rate (which is how fast it goes from zero lift to max lift) with a roller cam, and there is less friction. Modern oils also don't have certain additives in them, so flat tappet cams are more likely to wear prematurely now.