My 427 SOHC Build..... Finally the time has come!

[cobracammer]

Got a nice matching PCV and breather set from Jegs last night.  Will be here tomorrow  :0)

[My427stang]

I only run 10.7:1 with a DCR of 8.33 and a tight quench in my Mustang, the truck is 10.0 with a DCR of 8.2 and a bit looser quench.  Neither of them have an issue and every street engine I build gets a PCV.  Granted, I have not had the opportunity to build 12:1 street engines though FWIW less than 1000 miles on the truck engine, but the Mustang has been together, both in carb'd form and EFI since late 2006 and is as clean inside as it every has been.  It's got just a basic set of Mahle moly rings with a low tension oil ring set in it too

Keep in mind, the PCV certainly can pull vapor in, but PCV vacuum is high at light load, and low at high load, and near zero at WOT. So really the most vapor flow would be during the conditions least likely for detonation.

In fact, unless you have a blow-by problem or a lack of baffles, I have not even seen evidence of oil in the intake plenum, now if you have a blow by issue, then that needs to be addressed more than the PCV IMHO. 

Of course, as Jay said, it's cheap and easily undone too, so worst case, take it back off.

[Heo]

One alternativ is the....i think moroso
Vacu-pan the are called. Two valves in
The header collectors with a hose to the
Valve covers
Sorry saw that it wont work with mufflers

[e philpott]

One alternativ is the....i think moroso
Vacu-pan the are called. Two valves in
The header collectors with a hose to the
Valve covers
Sorry saw that it wont work with mufflers

I've run that Moroso set up for 15 years with mufflers no problems and it works , you do have to check the valves on occasion because they can blow/wear out , I've replaced my check valves probably three times over the years ....

[cobracammer]

Maybe depending on your Back pressure with mufflers vs without?

[cobracammer]

Hey Guys.  Had another thought.  If the reason for detonation is that the PCV valve lowers the octane rating on the 93 Octane Premium, I think I have an answer.

Sunoco Gas stations (Some of them) sell Race fuel!  There are 3 near my house that sell a product called "260 GT"  It looks like its 104 Octane.  If I used this (assuming I am correct on the cause of detonation), perhaps the octane rating will still be high enough?

Again this is all theoretical because I haven't even hooked up the PCV valve yet  LOL

Here is a link to the Gas stations info sheet on the 260 GT stuff:

http://www.sunocoracefuels.com/fuel/260-gt-plus






 

[Heo]

One alternativ is the....i think moroso
Vacu-pan the are called. Two valves in
The header collectors with a hose to the
Valve covers
Sorry saw that it wont work with mufflers

I've run that Moroso set up for 15 years with mufflers no problems and it works , you do have to check the valves on occasion because they can blow/wear out , I've replaced my check valves probably three times over the years ....

Volvo used valves like that for AIR in the exhaust
manifold without any smogpump so it Will probably
work even better with headers

[My427stang]

Hey Guys.  Had another thought.  If the reason for detonation is that the PCV valve lowers the octane rating on the 93 Octane Premium, I think I have an answer.

Sunoco Gas stations (Some of them) sell Race fuel!  There are 3 near my house that sell a product called "260 GT"  It looks like its 104 Octane.  If I used this (assuming I am correct on the cause of detonation), perhaps the octane rating will still be high enough?

Again this is all theoretical because I haven't even hooked up the PCV valve yet  LOL

Here is a link to the Gas stations info sheet on the 260 GT stuff:

http://www.sunocoracefuels.com/fuel/260-gt-plus

Running fuel with extra octane is likely good anyway, but I really don't think you will need to worry about it. 

[cobracammer]

Ok guys.  Took all day, but power steering rack is out, power steering cooler, power steering lines, pump and resevoir.... All out.  I made sure not to move the steering wheel once all was detached.  New flaming river manual rack in.  Installed new MOOG tie rod ends ( got it close to the steering wheel being straight when tires are straight).  Installed new breather on passanger side and new PCV cap on drivers side.  Still need to run the vacuum line and just snug up each oil pan bolts.  Almost ready to be let back down on its wheels!

[My427stang]

Ok guys.  Took all day, but power steering rack is out, power steering cooler, power steering lines, pump and resevoir.... All out.  I made sure not to move the steering wheel once all was detached.  New flaming river manual rack in.  Installed new MOOG tie rod ends ( got it close to the steering wheel being straight when tires are straight).  Installed new breather on passanger side and new PCV cap on drivers side.  Still need to run the vacuum line and just snug up each oil pan bolts.  Almost ready to be let back down on its wheels!

Looking forward to the results!

[cobracammer]

Small update.

OK, I did a rough alignment and the wheels are (to the naked eye) pretty straight in the front.  Of course its going to need a professional alignment.

I managed to get the PCV cap into the breather tube, and the matching breather cap into the passenger tube (which needed to be shortened a little more to make room for this new cap.  A length of 3/8" vacuum hose is run from the barb on the PCV cap to the larger port on the back of the throttle body (this was the original port I had connected to the vacuum assist brakes before I connected it to a barb on the back of the intake manifold).

I have been going under the car with a light each night to check for possible places the oil leaks have come from.  After wiping down the whole underside a few weeks ago, the only place I saw a shimmer of oil was where the oil pan butts up against the backing plate of the bell housing.  I was able to see that there was also a "line" of oil that came down the back of the scatter shield and was dripping off of the bottom of the bell housing.  I gave that all a wipe down and made a mental note (and a post on here earlier) about it.  Then last night I crawled back under the car to take another look (and wasn't expecting much as the car had not run since the wipe down).  I saw another drop of oil on the bottom of the bell housing ready to drip onto a tiny spot on the floor where it looks like 2 or 3 other drops fell.  The back of the backing plate is still clean and dry as is the other areas I wiped down.  I am guessing that the weak point that oil was pushing through because of pressure was the rear main seal?  This would explain why the oil is still coning out between the bell housing and the backing plate.  The most I can do is again make sure I snug up the oil pan bolts (if they need snugging) and hope the PCV valve and new breather lessens the crankcase pressure so the rear seal wont drip.  :0)

[jayb]

It could be the rear main or the side seals for the rear main bearing cap.  I didn't see any leaks on the dyno there, but you never know.  Also it is worth mentioning that any leak at the back of the engine (intake manifold to block, valve covers, etc.) can drip down the back and make it looks like a rear seal leak.  I know you've checked there, but since you've wiped everything down and new oil has shown up, likely you had some residual oil trapped between the block and backing plate or backing plate and bellhousing, and it just took a while to drain down to the bottom.

By the way, you're not using synthetic oil, are you?

[sixty9cobra]

If your thinking about using high octane fuel just make sure it is unleaded, lead will kill your O2 sensor in no time.

[cobracammer]

Hey Jay.  Thanks.  The more I think about it, the more I think its prob the main seal ( rear or possibly sides)  It probably happened when I downshifted  on my first or second run as the dripping does not occur when its at idle.  You start to notice the dripping after a drive.  It hopefully will be fixed now with better breather and PCV valve. 

Also, no on the oil.  I remember you said conventional was better forring seal, so i put 9 quarts of 10W 30 conventional oil 

[cobracammer]

Just as a side conversation, I have been thinking about my new found ability to alter fuel ratios before the computer goes into learning mode (reaches operating temperature).  I read online that engines with larger valve overlaps do better on a leaner air/fuel ratio.  Fortunately, with the new handheld, I have the ability to alter cold start fuel + or -.  I think I accurately calculated the valve overlap of these comp cams (63 degrees of overlap).  I have been trying to find some sort of "rough" calculation (more of a starting point actually) for Air fuel ratios on an engine with this amount of overlap for a cold start.  Again, once the car reaches operating temps and the Adaptive learning kicks in, the computer adjusts everything and the car runs beautifully.

I think idle Air/Fuel on this car is 13.5:1 (would have to double check), but since it seems to stumble and stall out at a cold start and not get to 1000 rpm. I wanted to start thinking about adjusting the ratio to get at least a clean idle before my roadtrip to allow the computer to learn.  :0)  (Hopefully this weekend)