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Computer questions

A buddy of mine has built himself up a 5.0 for his 88 bird and has a few questions about the combo and computer requirements. He has a stock 89 mustang block and internals and he added/re-used the following goodies...
1) Cobra upper and lower
2) 65mm throttle body and EGR
3) 19 lb injectors
4) A set of 1970 351 heads that have been ported and gasket matched as well as 1.90 intake and 1.60 exhaust valves have been installed,roller rockers as well.
5) set of ford racing pullies.
6) stock 89 cam
7) air and smog delete.
8) Mac unequal length headers and custom dual exhaust.

the question is as such...he has an 88 SD mustang computer that he wants to use for now, is that going to work out for him or will there be computer issues because of the heads and intake etc and because it is not converted to mass air? He will be getting a mass air computer and sensor in the future but will probably be quite some time before he gets it. Is he going to be alright?

What kind of power do you guys think he would make over the stock 225hp mustang 5.0 power, I guessed about 40 to 50 hp gain but what do I know? Any insight from you guys?

Thanks in advance.

Computer questions

Reply #1 –
The real stifler, so to speak, of SD is the port velocity. Things that change this too drasticly will have poor performance results. For instance a cam with too much duration ( I know I know... how much is TOO much?, right?) Dunno, but I do know that in keeping speed density you can forgo a different grind and still gain pretty substaintial power via rocker arm ratio- ie step up to 1.72: 1 ( if you have the HO pistons with the reliefs) Also, too free of flowing heads will drop the velocity below what an SD computer will take. Dropping the compression ratio also kills the SD's functionality. Basicly, if it's dropping the vaccuum, it's treading on bad ground. BUT on the bright side, you can usually pick up a mass air conversion from a stock 89 or newer mustang for around $300 on EBAY or a swap meet.PS when selecting a cam for SD keep the duration as close to stock as you can, but increase lift.

Computer questions

Reply #2 –
I think he'll be fine because of the stock cam...

Shameless plug...

But, if he does want to convert to MAF, I just happen to have a complete conversion that I'll let go for $275 shipped. Follow the link below for pics:

http://www.foxtbirdcougarforums.com/showthread.php?t=9094&highlight=complete+MAF+conversion
[SIGPIC][/SIGPIC]
86 5.0 Turbocoupe (Katrina), 87 5.0 Sport (Rita)

Computer questions

Reply #3 –
The heads came off a 351 so just check the chamber size if it’s to big meaning set for a 351 you cam have a loss off compression.

Computer questions

Reply #4 –
Speed density will be fine.
It's Gumby's fault.