TCCoA Forums banner

1 - 12 of 12 Posts

·
Registered
Joined
·
34 Posts
Discussion Starter #1
I am currently debating which cylinder heads to get for my DOHC swap, either the 03/04 cobra heads or the fr500s...
the car is going to be forced induction using the 03/04 cobra intake manifold w/ whipple supercharger and the fr500 camshaft in either case... so the question is which head do i use, the fr500 is a great head outflowing the 03 cobra at the lower end but the cobra is better at higher lifts, according to the SHM flowbench data also both heads will be ported, so which responds better to the port job and forced induction?
 

·
Super Moderator
Joined
·
11,961 Posts
i had posted up a pic i took from 5.0 Mustangs where it shows stock flow, and ported flow, by Houston Performance on pretty much all the 4V heads from Ford.....i cant find the pic, but i do still have the magazine, so i'll just post of those figures:

................FR500..................03/04 C head

Lift.......Intake..Exhaust......Intake....Exhaust
0.100....95..........63................98........68
0.200...175........137.............189........140
0.300...251........181.............266........189
0.400...306........205.............315........214
0.500...330........219.............331........229
0.600...340........226.............342....... 237

these figures are with both heads ported, @ 28" of H20

ported, the 03/04 C head will outflow the FR500 on the intake and exhaust

not surprisingly, 5.0mustang magazine chose those as the overall winner of their "flow war" in terms of time/money invested, not counting 2000 Cobra R/Ford GT Supercar heads.......when properly ported, the 03/04 C heads will outflow all other heads (93-98 Bheads, 99/01 heads, 5.4 Navi heads) on the intake side.....the ported Navi head, although, does blow the ported 03/04 C head outta the water in exhaust flow

so if you can get your hands on a decently priced set of 03/04 heads, it would be cheaper overall if you had them ported, instead of incurring the additional cost of getting new/used FR500 heads, and then having to get those ported and get the same results of more available/inexpensive 03/04 C heads
 

·
Registered
Joined
·
1,601 Posts
Ok,

Thread ressurection here...Is there a specific Mustang/ Ford vehicle that had the 'C' Heads so I know what to look for to find the heads?

Josh
 

·
Registered
Joined
·
7,758 Posts
................FR500..................03/04 C head

Lift.......Intake..Exhaust......Intake....Exhaust
0.100....95..........63................98........68
0.200...175........137.............189........140
0.300...251........181.............266........189
0.400...306........205.............315........214
0.500...330........219.............331........229
0.600...340........226.............342....... 237
Do you have the numbers for a ported "B" head from the same list? I know they aren’t the best, but if someone is going boosted, the "B" heads, with a little more boost, can be comparable to the other heads (but obviously not the best if you’re going for maximum power)(IMHO).

It’s just that the "B" heads are SO much cheaper and easier to find. :thumbsup:
 

·
Super Moderator
Joined
·
11,961 Posts
Ok,

Thread ressurection here...Is there a specific Mustang/ Ford vehicle that had the 'C' Heads so I know what to look for to find the heads?

Josh
99/01 cobras, aviators, and possibly the 99+ continentals had the C head

but.....keep in mind that the newer tumble-port C heads which debuted in 03+ vehicles like the Mach1, Marauder, Cobras are a revised casting that featured better coolant flow to the #7 & #8 cylinders....this alleviated a "ticking" problem on the early C heads that caused damaged to the valves/valve seats
due to too much heat

Do you have the numbers for a ported "B" head from the same list? I know they aren’t the best, but if someone is going boosted, the "B" heads, with a little more boost, can be comparable to the other heads (but obviously not the best if you’re going for maximum power)(IMHO).

It’s just that the "B" heads are SO much cheaper and easier to find. :thumbsup:
yes i do, i'll post the #s up tonight (im at 'work' right now lol)......i do remember that the #s look good, but they are not the result of increased velocity, but rather sheer massive port volume, which like you said is great for forced induction, and not really N/A unless its a 8000+ RPM screamer
 

·
Super Moderator
Joined
·
10,319 Posts
99/01 cobras, aviators, and possibly the 99+ continentals had the C head

but.....keep in mind that the newer tumble-port C heads which debuted in 03+ vehicles like the Mach1, Marauder, Cobras are a revised casting that featured better coolant flow to the #7 & #8 cylinders....this alleviated a "ticking" problem on the early C heads that caused damaged to the valves/valve seats
due to too much heat
Do you know any casting numbers for those heads?

The aviators aren't that hard to find; are the aviators the tumble port design?

Is the coolant flow in those heads better than b heads with the coolant mod?

Inquiring minds want to know... :D
 

·
Super Moderator
Joined
·
11,961 Posts



thats from 5.0 Mustangs & Super Fords Magazine, Dec. '04

i dont know the casting #s for the heads, but im sure a quick google search will yield some results.....the aviators are definitely tumble port, with the 03+ aviators having the best heads

with the coolant mod, i think the B heads would have better cooling of the #7 & #8 cylinders, but then again, with the coolant mod to the 03+ tumble port heads it would be even better :D

i do want to point out though, that there are some discrepancies with cylinder head flow data....this is out of sean hyland's book:




Hylands book has flow data @ 25" H2O, so you would need to add 6% for the 4V head flow data......even with 6% added, the FR500s (stock) dont seem to match the flow indicated in the 5.0 Mustang article

http://www.modularfords.com/forums/showpost.php?p=230252&postcount=48

according to a post by Boss330 (who wrote the article in 5.0 Mustang), stock Cobra R/Ford GT Supercar heads flow 304/255.....so i dont know if stock FR500s are that close to bone stock R heads
 

·
Registered
Joined
·
1,601 Posts
Ok,

pardon a Newbie question on this one.

Since I'm going to use a blower on my 4.6L DOHC project, What is the recommended procedure to do to a set of heads/ intake? Do I port them both, or do I leave them as is to keep the velocity up? Aside from owning a SC, I know precious little about making them scream.

Josh
 

·
Like Titles Matter
Joined
·
2,129 Posts
Ok,

pardon a Newbie question on this one.

Since I'm going to use a blower on my 4.6L DOHC project, What is the recommended procedure to do to a set of heads/ intake? Do I port them both, or do I leave them as is to keep the velocity up? Aside from owning a SC, I know precious little about making them scream.

Josh
These things pick up pretty much nothing from porting if they have a PD blower on them, save your money.
 

·
The Parts Guy
Joined
·
7,269 Posts
These things pick up pretty much nothing from porting if they have a PD blower on them, save your money.
Agreed. What little gain you may see from porting, in a PD blower application, it simply won't be worth the time/money involved.

-Rod
 
1 - 12 of 12 Posts
Top