Cylinder head swap

Gunmetal5oh · Dec 20, 2011

Swapping heads on my 89.
I have two choices for cylinder heads that I already OWN.

A fully reconditioned set of E7TE heads I put together with heavy duty valve springs.
A used set of ported/polished 1969? 58cc heads with heavy duty valve springs.
Which would you choose?? (I cannot afford to have the E7's ported!!)

I was going to use the E7TE's and just use the stock rockers.
What will I need to do if I decide to use the 69 heads?
They should be 58cc which will give a slight compression bump. (stock E7TE is 62cc??)

I have some leftover CompCams Magnum roller rockers and studs.
Any way to use stock rockers on the 69 head?
DO I NEED ADJUSTABLE ROCKERS WITH A THE .540" LIFT CAM?

Car has stock bottom end.
Upgrades include:
Performer RPM EFI intake
FORD RACING X303 Cam
24lb injectors
70mm BBK throttle body
73mm C&L w/blue tube (on the way)
BBK cold air intake
EGR delete
shorty headers
flowmaster 40's

Gunmetal5oh · Dec 21, 2011

1969 302 heads C9OE "C90E"
58cc chamber

Do I go with these heads OR a stock E7TE?
'69 heads should bump my compression ratio to 9.5:1

Jason 302 · Dec 21, 2011

I was able to go high 12's with my self ported E7's, they're not that bad of a head with a little DIY port work.

http://www.diyporting.com/E7OV.html
http://www.diyporting.com/E7p2.html

Gunmetal5oh · Dec 22, 2011

I've decided to run the stock E7TE heads.
Only change is I will be using the Comp Cams Magnum roller rockers from the '69 heads, part # 1431-16
That way if I sell the car in a year or two I will still have the 69 heads and can have them ported in the future.

need4spd90 · Dec 23, 2011

those are 3/8" stud mount rockers, E7's use 5/16" pedestal mount rockers..you're going to have to take the heads to a machine shop to have the 3/8" studs installed..it'll be cheaper just to buy a new set of 5/16" pedestal rockers

what are the specs or part # on the valve springs you plan on using with that cam?

Gunmetal5oh · Dec 23, 2011

You're right. I thought I could use them but turns out it was a different part #
I'll go ahead and use the '69 heads so I can use the roller rockers, and because it looks like the 69 heads have been ported a little bit.
Check it out... how much increase in flow do you think that will yield?

need4spd90 · Dec 23, 2011

tough to say...
what springs are on those heads?

valve springs are always overlooked, and they're probably more important than the cam itself..if the springs cant properly control the valves, the cam isnt going to do anything but float the valves and/or cause the springs to coil bind...and if you break a spring and drop a valve..lookout...

also, those C90E heads originally came on a 351w i believe, so you'll have to get 1/2" to 7/16" stepped heabolts, or at least some bushings to take up the space in the bolt holes..351 blocks use 1/2" headbolts, 302's use 7/16"

Gunmetal5oh · Dec 23, 2011

They are C9OE 302 heads.
Casting number says 302, the first pic I posted shows the casting mark.
Tom Monroes book "How to build a small block Ford" incorrectly states these heads as being from a 351.
The 302 version is more rare, as far as I know.

They are 69, 302, 58cc heads, 1.78 intake/1.45 exhaust valve sizes.
Should yield a 10.5:1 compression ratio with stock pistons.
The porting job on them is not the smoothest I've seen, but the exhaust side has been opened up considerably.
Going to use these ones!

These heads were rebuilt a long time ago, but haven't been run much at all.
Along with the Magnum roller rockers, they have high tension dual valve springs installed.
Not sure what springs exactly, but I believe they were rated for around 5.50" or 6.00"

need4spd90 · Dec 23, 2011

sounds like you'd be better off with the C90 heads than the E7's...even though the spring specs are unknown, at the very least they're a dual spring...

how are you going to get 10.5:1 with stock fox pistons and a 58cc head? you'll be lucky to hit 10:1

Gunmetal5oh · Dec 23, 2011

Whoops, should hit 9.5:1
I don't know why I was thinking it was 10.1 already. It should be bumped half a point.
Springs aren't exactly unknown, I just can't remember an exact number. I know they support more than the last cam they were run with, which was a .520

need4spd90 · Dec 23, 2011

"lift capability" isnt all there is to valve springs..just cuz a spring will "handle X amount of lift" doesnt necessarily mean its matched to the cam...ideally, the peak lift should be .060"-.080" from coil bind,possibly even .100" for higher rpm setups, and valve closed and open pressures need to be correct for the type of cam you're running..most aftermarket hydraulic rollers should be somewhere in the 120-140lb on the seat area, and see at least 350lbs with the valve fully open(400+ for higher rpm setups), while a solid roller will need alot more seat pressure, and a flat tappet cam will need alot less,...so, for example, if those springs were designed with pressures to control a flat tappet cam and you're trying to run a hydraulic roller with them, you'll probably still experience valve float,especially at higher rpms, since there wont be enuff spring pressure to properly control the valve while the valve is open..

was the last cam a hydraulic roller?

Gunmetal5oh · Dec 24, 2011

Makes sense. The last cam was a flat tappet Performer RPM which had max lift of .520, however the springs still supported more cam.
New cam is .542, a difference of 22 thousandths, I believe it is pretty darn close.
The main springs look identical to the springs I installed on the reconditioned E7TE heads.
I could always swap the new springs from the E7TE heads onto the old heads, which is what I will probably do!

Don't have a valve spring pressure tester.

PS. It looks like the springs on the E7TE heads have 3 springs, the ones on the 69 have 2.
There is a fat outer spring, then a thin wide spiral spring, and a third lightweight spring on the inside. I'm guessing the 3 spring design is for roller cams of higher lift?

need4spd90 · Dec 24, 2011

first off, stop getting hung up on lift...springs for a .550 lift flat tappet cam will still not have enuff pressure for a .550 lift hydraulic roller, even though the coil bind clearance for both cams might be fine..lift is not "more cam"..its "more lift"..thats all...and when it comes to valvetrain stuff, .022" is alot

your X cam and my B cam are perfect examples. the X cam is a B cam with more lift..they have the exact same valve events, same duration @ .050" lift, same Lobe Separation Angle..the intake and exhaust valves open and close at the exact same degree of crankshaft rotation on both cams..the X cam has taller lobes, which = more lift..i run my B cam with 1.72 rockers..this brings peak valve lift to up from .480 with 1.6 rockers to .516..there's still a .026" difference in lift..so since they have the same exact valve timing events, does that make the x cam "more cam"?..dont think so..just means it has more lift..spring pressures needed are the same, coil bind clearance will be different, in this case...

without the proper spring pressure, you will have valve float, plain and simple

the "wide spiral thing" is a damper, not an actual spring..so it sounds like the E7 springs are actually a dual spring with a damper

you dont have ANY idea what springs you installed on the E7's??

Gunmetal5oh · Dec 24, 2011

OK. Found out the springs are Howards Cams 98432
http://www.summitracing.com/parts/HRS-98432
Max lift of .625"

Delivers increased valve train stability and performance over OEM springs. Made from premium chrome silicone, coiled and heat-treated in the finest facilities available. Designed for most performance hydraulic and mild mechanical flat tappet applications.
STOCK DIAMETER PERFORMANCE VALVE SPRINGS

Here are the valve spring specs:
Open Pressure: 285#@1.25
Seat Pressure: 135#@1.750
Rate: 300
Coil Bind: 1.062
Max lift of .625"

need4spd90 · Dec 24, 2011

ok so lets do some math...
installed height 1.75- 1.062 coli bind = .688" lift to coil bind.
.688"-.542"= .146" coil bind distance..not exactly in the ideal .060-.080" range now is it?

now for the pressures
135lbs on the seat isnt bad..BUT...with a rate of only 300lbs/in

300x .542"= 162.6 lbs
162.6 + 135(seat pressure)= 297.6 lbs with the valve fully open..not exactly ideal for a hydraulic roller cam, now is it? especially considering the item description specifically states they're for flat tappet cams...better than stock, i guess, but not by much...

those springs dont match the cam...i can recommend a better set..they cost about $160, no machine work necessary, but you'll need to check installed height and possibly shim for coil bind distance..Crane #44308-1..i run these on my car..they work excellent

for your setup, i'd install them at 1.930"

they have a 457lb/in rate
@ 1.930" they'd install at 127 on the seat and give you 374lbs with the valve open and be .068" from coil bind..that will surely handle the X cam, and you should easily be able to spin that to 6k + with no worries of floating the valves

just my $.02

Gunmetal5oh · Dec 25, 2011

I'm not too knowledgeable about spring calculations, but they are new springs that came with the E7's.
I was told they would work because the X cam has a mild ramp rate and it only needs 110-115 pounds on the seat, where other cams need 130 or so. Though it does provide 135.
These 98432 Howards Cams springs are stock diameter and will work with hydraulic roller or flat tappet.

What I don't understand is why they are rated to .625" lift but won't work with my app.
X303 cam and I want to run it out to 6500RPM (Rev limited) with a Performer RPM EFI intake.

These aren't ideal because of the 300 spring rate??

need4spd90 · Dec 25, 2011

Designed for most performance hydraulic and mild mechanical flat tappet applications.

hydraulic flat tappet isnt hydraulic roller

you can actually be too far from coil bind, as well as too close, and have it start floating the valves..the ideal distance is to be within .060-.080" from coil bind, maybe even .100"

the spring rate doesnt give it enuff pressure when the valve is open...297 with the valve open is really borderline..i highly doubt you'll see 6500rpms(also since the stock computer rev limiter is 6250 lol)...you can probably get away with these, since like you said its a kinda mild cam, but personally i wouldnt do it..i'd run those Crane Beehives i linked to..just saying be aware, theres horsepower hidden in the valvetrain that you're not going to be taking advantage of

Gunmetal5oh · Dec 25, 2011

I have a 6AL box and read it would bypass it, looks like that is not so! Rev limiter must be in the ECM. Thanks for clarifying.

Gunmetal5oh · Dec 25, 2011

Can you recommend an more inexpensive valvespring that will work?
I've already got retainers and locks.

need4spd90 · Dec 26, 2011

thats about the cheapest it gets...locks and retainers arent universal, so you cant just pick a random spring and expect random retainers and locks to fit, ya know

the 6al rev limiter will not "override" the computer, but the 6al will still work before the 6250 factory limiter kicks in..so if you put a 6200 pill in the 6al for example, you'll hit the 6200 limit on the msd box first

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