Porting E6 H.O Heads

[joeythesaint]

A'ight. My engine just blew up and the summer's wasting.

I'm building fast and cheap, here; all I have to work with is about $300 and a VERY clean '86 H.O. New heads are not an option; I'm blowing what disposable cash I've got on a cam, timing set, gaskets, and enough beer and pizza to build this sucker in 2 weekends.

FWIW, I"ll be putting in an e303 cam -- the .498/.498 is as close to the .500 clearance I'll get with the flat-top pistons -- and bolting on my dual-quad tunnel ram rig intake. This winter (which starts in October), I'll be stroking to 331 with KB pistons and an X cam and slapping some new heads on top. For now, there are 6 weeks of summer left in the Northwest (if we're lucky), and I want to spend the last five of them eating Rice.

The E6 heads have fairly beefy intake ports; they almost match the gasket on the sides. The tops and bottoms of each intake port I can shave 3/16", and I can grind out the hump inside each intake port (swirl thingy) and of course the emissions nipples on the exhaust ports, and polish it down. I'm thinking that should help considerably.

(I'll make the joke about polishing a t-rd, just to beat you to it.)

Now, WTF is up with the cast, double-hump piece on the underside (cylinder facing)?

Has anyone ever ported a set of these, and if so, can you grind that piece right down flush? If so, how does it affect compression?

AvdTHANKSance,

- Joey

 

[90mustangGT]

E6's shrowd the valves, not a good head to mess with when E7's you can get so cheap and they clean up better.

 

[joeythesaint]

That's it, the shroud thingy. Does that increase compression? What the hell were they thinking?

As for E7's, I have neither the money nor the time. I'll put monster heads on it this winter when I build the stroker. An "intermediate" head would be a waste of a couple hundred bucks and a few weeks of precious sunshine.

If you lived in Seattle and had a T-top, you'd understand the deadline I'm under. It will start raining in October, with occasional sun breaks in June. Serious.

 

[Michael Yount]

Joey - educate yourself - peak lift has absolutely nothing to do with p to v clearance; the pistons are WAY down the cylinders when the valves are open to peak.

You better mock it up and take some drop valve measurements - the E cam is likely to be real close on clearance with the stock 86 pistons unless you cut valve reliefs in them. Also, I hope you're not serious about a dual-quad tunnel ram intake with those heads. I don't think you're gonna be happy with the results.

By the way - why did the engine blow up? What was the cause of the failure?

Slow down - save some $. There'll be another summer after this one.

 

[MrKwik]

A tunnel ram and a big cam with E6 heads isnt a recipe for "eating rice"...it's a recepie for rice to hand you your ass. Not trying to be negative or anything but those heads will have long since petered out by the time the intake is into its power range. All you will spend the rest of the summer doing is trying to tune the thing to stop fouling plugs and not die at stoplights.

....but thats just me

 

[joeythesaint]

The last engine died because it was old and seriously built and I was hammering the crap out of it; it sucked a valve and what we're thinking now is that one cylinder had cracked.

As for the cam/heads combination, I've double- and triple-checked it -- I've run it by a couple of shops, Ford Racing, and Edelbrock (when I was looking at other cams), and the .498 /.498 should work fine in the '86 H.O. Bigger than .500 /.500" and I'm toast. I'm told that "a miss is as good as a mile" -- as long as the cam lift stays under .500 there shouldn't be any problems.

If P/V clearance isn't a function of cam lift, then why is the .500" mark so critical on the '86 engines? Serious question. What is the issue if it's not p/v clearance?

The tunnel ram ran great on a built '78 302 with 289 heads -- same size valves and smaller ports than the E6's. Hell, it ran better than great with that combo; it was ferocious. The e303 is comparable in size (slightly smaller) than the cam that was in the last build, and the E6 heads will have better flow. Frankly, I was told that the tunnel ram wouldn't work on that engine, either. That I'd spend every weekend tuning it, that it'd die at lights, that it wouldn't ever idle, that it'd have no power until 4000 rpm, that the heads were too small, that the engine was too small, etc. etc. etc.. . . see the 2nd page of my cardomain site for a full list of warnings I received from people who "know about tunnel rams." No offense intended, but I know that the aspiration end of the equation will work because I've already run it on an engine of equivalent displacement and it kicked ass.

(EDIT: Worst case, I'm wrong. It doesn't work. I'll chalk it up to the learning curve. A fresh set of pistons and/or a smaller cam (like the .444"/.444" that's in there, now) and I'm back in the game two weeks later.)

That said, I just want to know what the shroud on the head is for, and what the consequences would be for removing it.

 

[z2o_what]

i just ported a set of e6's and i also enlargened the combustion chambers (die grinder) around the intake valves...

i should have my motor back in the car in a few days...so ill let you know how / if it runs

i also have befor/after pics of my "custom headwork" that i need to get developed

 

[Michael Yount]

I'm told that "a miss is as good as a mile" -- as long as the cam lift stays under .500 there shouldn't be any problems.
If P/V clearance isn't a function of cam lift, then why is the .500" mark so critical on the '86 engines? Serious question. What is the issue if it's not p/v clearance?"

You should get different sources for advice. People that tell you that .500" lift is a critical dimension for the 86 motor simply don't know what they're talking about. I'll try one more time - but you don't seem to be listening -- not sure why you posted.

At peak valve lift, the pistons are way down the cylinder. If you've ever degreed a cam and measured p to v you'd understand. Minimum p to v clearance occurs during overlap - when the piston is passing through tdc at the end of the exhaust stroke and the beginning of the intake stroke. The exhaust valve is just closing and the intake is just opening. ON the E cam at the valve timing recommended on the cam card - at tdc both intake and exhaust are only open .050" X your rocker ratio - around .080" w/1.6; .085" w/1.7's. Somewhere within 5 or 10 degrees before or after that tdc is where minimum clearance will occur. You can see, it doesn't matter what the peak lift is - by the time the valve reaches it, the piston is near the bottom of it's travel and is INCHES away from the valve.

The things that impact p to v include bigger valves, valve size or placement that doesn't match the reliefs, cutting the head/block and earlier opening intake timing or later closing exhaust timing --- in your case with the same heads/pistons - it's the E cam's tighter LSA and increased duration that cause earlier intake opening and later exhaust closing that cause a reduction in clearance.

NO ONE can tell you if you're gonna have enough clearance when you start changing cams/heads --- YOU MUST MEASURE YOUR ENGINE to find out. Even two engines with the same exact parts can have significantly diffferent clearances -- when you start measuring things in hundredths/thousandths of an inch, differences show up.

Lastly, a miss is definitely not as good as a mile. You can have plenty of clearance to crank the motor and even run it relatively hard -- only to find on the first missed shift (and the accompanying over-rev) that the valves float and all 8 exhaust valves hit the pistons. Many people out there have learned that the hard way.

ESPECIALLY with the pistons in the 86 (no reliefs) measure p to v. You should have a minimum of .080" intake; .100" exhaust if you want "a miss to be as good as a mile". Just to be crystal clear - I'm not suggesting you WILL have clearance issues. I'm suggesting that unless you actually measure, your method of knowing whether you have enough clearance or not is simply guessing and hoping. Not a very effective way to build an engine -- often a VERY effective way of having to build another one real soon after this one goes together.

And with the combo you've described, you'd be better off all the way around with a simple single 4 bbl intake and carb - no more than 600-650 cfm.

Good luck with it.

 

[Michael Yount]

A late add -- the issue that most folks are probably referring to regarding .500" lift is to be sure you have the proper springs that will control that lift and not get into bind.

Also - there are quite a few folks out there working 'in the business' that don't understand p to v clearance. Yes - even folks at FRPP and some of those on the tech lines at some of the cam companies and at places like Summit and Jeg's. So just because they're selling the parts doesn't necessarily mean they truly understand all the issues associated with them.

If by "double and triple checked it' you mean you've measured and you've got the minimum clearance, then ignore my post. If by that you mean you've talked to 2 or 3 people and they all say the same thing.....then you still need to measure.

 

[joeythesaint]

Thank you, Michael. I will go over the entire assembly with clay and a dial indicator, turning the engine by hand, once I get the cam, which should be this week. I've measured it already with a dial indicator and it looks like it should work. It's going to be close -- very close -- but with the right springs it should be okay.

>it's the E cam's tighter LSA and increased duration that cause earlier intake opening and later exhaust closing that cause a reduction in clearance.

That wasn't explained to me, before. Thank you. Excellent post.

 

[Michael Yount]

Good luck - let us know how it turns out.

 

[noobstang86]

Im trying to put an 86 h.o. motor together as im posting this, and fyi the stock not even decked e7 heads will NOT clear the flat top pistons even with a stock cam. i have a couple real nice dings in my pistons from testing this theory :-( take this how u want, but didnt work for me... back to the e6 head

 

[noobstang86]

not that i meant to drum up a dead topic but i just though i shoud throw it out there, if anyboy has any advice on what to do with this motor and head issue, i am trying to run my stock flat top 80K motor with some goodies ie... my polished cobra intake, bbk 70mm tb and maybe a little cam. but the problem is the ported e7s i have do not work.
should i just leave the stock cam in, stock e6 heads and then add my bolt ons?
should i see about getting the heads ported a little?
is there an aftermarket head with a tall enough chamber that they wont hit the head?
how much lift can i run with the stock heads block and pistons?
btw this motor is out of an 87 lincoln mark8
thank you anybody for help with this

 

[noobstang86]

...Anybody? Are the Trick Flow TWs the only ones that will work? and yes I have been trying to search for info. Please help...

 

[1987stangman]

not that i meant to drum up a dead topic but i just though i shoud throw it out there, if anyboy has any advice on what to do with this motor and head issue, i am trying to run my stock flat top 80K motor with some goodies ie... my polished cobra intake, bbk 70mm tb and maybe a little cam. but the problem is the ported e7s i have do not work.
should i just leave the stock cam in, stock e6 heads and then add my bolt ons?
should i see about getting the heads ported a little?
is there an aftermarket head with a tall enough chamber that they wont hit the head?
how much lift can i run with the stock heads block and pistons?
btw this motor is out of an 87 lincoln mark8
thank you anybody for help with this

Im confused on WHY the E7's wont work? I had a hodge podge 86 motor from a Crown Vic that I stuck a set of ported E7's and a stock HO cam and it ran fine in a 88 Ranger truck. There has to be some other reason why those heads wont work that I am missing.

 

[Maryland Stang]

Also - there are quite a few folks out there working 'in the business' that don't understand p to v clearance. Yes - even folks at FRPP and some of those on the tech lines at some of the cam companies and at places like Summit and Jeg's. So just because they're selling the parts doesn't necessarily mean they truly understand all the issues associated with them.

If this ain't the truth! Just last week I had a major blowing of smoke up my butt. This rep of a major aftermarket sales company told me a lie that doesn't get any bigger. He told me that his company had taken a certain specification into account for a part that was custom made for me. Now how they managed to do that is beyond me since I never told them what the specification was.