valve spring questions?

[muzzy25]

hi got some edelbrock rpm heads 60225
I was going to use 1.7 roller tip rockers stock cam should be about 480 lift .but rockers are rated at 350 psi
head springs rated 150psi closed open 420 psi
do i need to change springs or get full roller rockers?
is there any difference in performance between 1.6 vs 1.7 with these heads
running an explour manifold
have you had any trouble with prw pro series roller rockers ?
hard to find answers over here ?

 

[Wmac]

If you have the 5845 dual springs, then you are good to go with almost any camshaft.

1.7 rockers add about 030 lift, so as long as ptv clearance is not an issue, why not.

Is prw not a highly respected Australian company?

 

[muzzy25]

got 5845 springs in it
looking for stainless steel 1.7 that will fit under my 3inc alloy rocker covers 3/8 stud
any suggestions ?
thanks for your help

 

[muzzy25]

after more research these have ed 5767 springs 110psi closed open about 290 psi ed60229 heads build in 07 still wrapped in plastic have you"s had any issues with trick flow or scorpion 1.72?

 

[Wmac]

What are the specs on your engine? What camshaft?

These are older heads that you bought used?

 

[muzzy25]

hi these are new heads my mate brought in from the usa 12 yrs ago and didn"t use them engine has stock cam explorer manifold going to port lower stock 19 injectors stock throttle body and mass air cold air intake
aode been rebuilt 4.6 high stall converter fitted and adapted bauutamer shift kit up rated transmission
there is no tuning shops here unless you do it your self or remote tune?
do you know part nm for 19 lb explorer ? as the explorer engine came out in the austrailian falcons with edis ignition p heads some had yella terra rr
might go to xe 264 ? trying to stick to limitations of stock ecu?
any help would be great

 

[Wmac]

The following is my opinion only:

If you are not going to change the camshaft, don't worry about the single 5767 springs. For any cc grind, change to their recommended springs.

For piece of mind, I would pull 1 spring and check for either spring cups or spring shims. You will need to know this before any upgrade. If you can get the explorer style injectors (4 hole) for cheap, grab them.
Are the yella terra rockers pedestal or stud?

If you want drivability, avoid a camshaft and throttle body upgrade.

Trans sounds like a very good build, what rear gear?

What's your objective? Strip, track or weekend cruiser.

 

[muzzy25]

hi i"m going to stick to stock cam yella terra rr are pedastal mount you can by them new stud mount about $1000 nz
i was looking at a pair off gt 40p head that was off a ts50 falcon witch was fitted with 1.94 inlet 1.5 ex factory heads motor was 347 wan"t $1500 and had 1.72 for it extra
paid $1000 for edelbrocks at shops sell for$2300+tax for e streets afr $3500 up
instructions for head fitting said 5767 springs which is a single spring ?
these looks like a damper spring inside may be 5825 i my have to take one out or messure retainer
diff ratio 2.73 daily driver
my work mate is going to be drag racing this y bloke so i may have a go

 

[Wmac]

2.73 gears won't take advantage of your trans or engine upgrades. Just my opinion. What ecm do you have?
5767 and 5825 are single springs with damper. 5845 is a dual coil.

Sounds like you got a great deal on the heads, if you have no intension of a camshaft upgrade, why not just run them as is. Rockers of your choice. Maybe the comp cams stamped steel w/roller tip? They are economical. Valve cover clearance may become an issue with any rocker.

If you have not installed them yet, I would pull at least 1 exhaust valve, Remove the spring and note and/or measure what is under them.

I run an old used pair of 6037 heads. I rebuilt them with original parts. (5767 springs, 9724 retainers, 9611 locks and 9725 seals) 2 or 3 years ago. I lapped the valves, smoothed and polished the ports. They had been milled 030 before I got them. I shimmed each spring (used hardened shims) as close as possible to 1.800 height. With stock cam and 1.7 cobra pedestal rockers, it pulls strong to 5400/5500. Have stock cobra upper, self ported explorer lower, 65 mm ford racing t/b, 19# explorer injectors, canned tune to raise the limiter and change fan turn-on. With 4.10 gears and drag radials, its a hoot to drive.

The above works well for me and is just my opinion.

Good luck with your build.

 

[muzzy25]

hi thanks for your help
i,m going to use 1.7 comp roller tip with push rod kit summit
diff nugget from explorer 3.55 heap at wreckers?
pull all springs and check guides and sets? find some injectors ?

 

[Wmac]

Just so we know, you do have a 94 or 95 Mustang?

Explorers have a 31 spline diff, mustangs are 28 spline. But the ring and pinions are the same. You would also need a gear change kit, its about 100 usd.
If your aode has a 4r70w gear set, 3.55 are a good all round gear. No more than 3.73 for strip or everyday use. I think you will need a tune for the change in trans gear set and to change the fuel limiter.

If the heads are new and never been used, no need to pull all the springs or even check guides. But 1 exhaust and maybe 1 intake valve should be pulled to see if there is spring cups or shims. If the springs are shimmed, note the thickness and colour of the shims. Take a photo as it will be important to know.

You should be just fine with the stock 19# injectors, I suggested the explorer 19#ers if they can be bought cheap.

This is all just my opinion, maybe someone else can offer suggestions.

 

[muzzy25]

hi yes it is a 1995 mustang came out off japan left hand drive brought it 2005 has all lights for nz . at that time had to change to right hand drive .got a conversion kit out of a
australia $10 grand paid $9.5 for car. conversion place won"t $18 grand + tax to convert.
is a aode at time off rebuild asked about 4r70w gear.set i would have to up date ecu software . so i raised stall instead.ecu is a fclo witch is about w4ho shift setting different and extra set off sencers behind cats .since no pollulition controls cats smog pump gone