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Topic: B303 + Speed Density = ?? (Read 4694 times) previous topic - next topic

B303 + Speed Density = ??

Reply #15 –
Per Ford Racing:
 On EFI engines, performance camshafts work only with mass air induction systems.(B303, E303, F303, X303, Z303 cams)
 Speed density system, airflow is "inferred".
 Mass air system, airflow is measured directly. It reacts faster and more accurately to changes in airflow and improves idle quality and overall vehicle perfromance.
[SIGPIC][/SIGPIC]88 t-bird: 5.0ho, gt40y, crane 2031, fms 1.7, paxton@5#, aod wide ratio, tci stall, performer rpm upper, 70mm bbk, pro m 60, 42#s, 3.73 7.5" posi, jba shorties, borla, upr x. 13.4 @ 104mph. cbaza, moates, tuned by decipha

B303 + Speed Density = ??

Reply #16 –
Quote
It reacts faster and more accurately to changes in airflow and improves idle quality and overall vehicle perfromance.


FYI 87-88 5.0 HO' were the fastest in bone stock trim.  If you can tune it properly SD is the way to go.  Problem is that it gets expensive when you start playing with longer duration cams.  Mass Air is much more forgiving in stock trim (OEM-wise) and cheaper.  WIth some skills you can tune it though.  Once you go balls out you'll need an aftermarket ECU anyway so.....
-- 05 Mustang GT-Whipplecharged !!
--87 5.0 Trick Flow Heads & Intake - Custom Cam - Many other goodies...3100Lbs...Low12's!

B303 + Speed Density = ??

Reply #17 –
Good job thunderjet with that speed density setup! Looks like a  quick car.
[SIGPIC][/SIGPIC]88 t-bird: 5.0ho, gt40y, crane 2031, fms 1.7, paxton@5#, aod wide ratio, tci stall, performer rpm upper, 70mm bbk, pro m 60, 42#s, 3.73 7.5" posi, jba shorties, borla, upr x. 13.4 @ 104mph. cbaza, moates, tuned by decipha

B303 + Speed Density = ??

Reply #18 –
Quote from: 1WLD BRD;188748
um, thats why the '87-'88 stangs where faster out of the factory then the '89-'93's?  I had my stock speed density '88 stang running in the 12's @104mph...  Thats not fast?


 Were the specs on the cams the same? Did the small mass air meters have anything to do with the later models lower power? Were the compression specs the same?
[SIGPIC][/SIGPIC]88 t-bird: 5.0ho, gt40y, crane 2031, fms 1.7, paxton@5#, aod wide ratio, tci stall, performer rpm upper, 70mm bbk, pro m 60, 42#s, 3.73 7.5" posi, jba shorties, borla, upr x. 13.4 @ 104mph. cbaza, moates, tuned by decipha
 

B303 + Speed Density = ??

Reply #19 –
Quote
Were the specs on the cams the same?


There was a change in '91.  A slight one, but as far as 87-90 yes they were.

Quote
Did the small mass air meters have anything to do with the later models lower power?


Realisticly? 5hp.  MAX  In stock form anyway.

Quote
Were the compression specs the same?


Yes.  Same heads, block, pistons, rods, crank, and head gaskets.  Piston change in '93 to Hypereutectic as opposed to forged.  Same specs on size, comp. height, valve relief size, etc.....


****** There is hearsay that the '86 and VERY EARLY '87 cam in the HO was an ever so slightly different grind that was a little more aggresive.  I've never heard confirmation or seen any hard facts or evidence to support whether this is in fact true ******EDIT the HO cam had a part # change for the 88 model year....the cam may have snuck in some late 87's.....
-- 05 Mustang GT-Whipplecharged !!
--87 5.0 Trick Flow Heads & Intake - Custom Cam - Many other goodies...3100Lbs...Low12's!

B303 + Speed Density = ??

Reply #20 –
Quote from: t.birdsc;188883
Good job thunderjet with that speed density setup! Looks like a  quick car.


It's a bit quick ;)

Quote from: V8Demon;188886
There was a change in '91.  A slight one, but as far as 87-90 yes they were.



Realisticly? 5hp.  MAX  In stock form anyway.



Yes.  Same heads, block, pistons, rods, crank, and head gaskets.  Piston change in '93 to Hypereutectic as opposed to forged.  Same specs on size, comp. height, valve relief size, etc.....


****** There is hearsay that the '86 and VERY EARLY '87 cam in the HO was an ever so slightly different grind that was a little more aggresive.  I've never heard confirmation or seen any hard facts or evidence to support whether this is in fact true ******


IIRC the engine components (H/C/I) were the same (excpet for the slight chance that the 86-87 cams were a bit better). The major difference was in the computer calibration. Each successive year from 87 on the computers got a little less aggressive programs to help with emissions.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

B303 + Speed Density = ??

Reply #21 –
Quote from: thunderjet302;188942
It's a bit quick ;)



IIRC the engine components (H/C/I) were the same (excpet for the slight chance that the 86-87 cams were a bit better). The major difference was in the computer calibration. Each successive year from 87 on the computers got a little less aggressive programs to help with emissions.


So in essence a 88 would be less agressive then a 87 and 87 less then 86...
Is an 86 HO speed density computer a decent one to run then? I found one local for a decent price.

Also, the 1986 SD HO uses 19 lb injectors right? If so, could I go grab the 19lb injectors from a 93HO (MAF Duh) Cougar I saw in the junkyard and use those without a problem?

B303 + Speed Density = ??

Reply #22 –
Basically any HO computer will operate any orange top 19lb inj...

My 5 speed '86 5.0 stang used to buck like a sum bish unless I ran Amoco premium... Ran good though... Converted it to Mass Air using a '89 A9P auto EEC(was told it was a stick)... Still bucked(& lost .25 sec at the track).. Finally sold it and kept the A9P... Inst that same EEC in my Bird, it bucked... Tried a C3W1(Motorsport EEC), it bucked... Finally a '89 A9L from the flooded stang convert fixed the problem...

Yea more info than you wanted, but gives a idea how different EEC's can react...