Yea, that'll definately bleed 'er down. You know you here all the crap about "obsolete" cam profiles, yet here the cam companies are offering just that..................the old "out dated" cam profiles...............that also happen to still work. And sound good. Just me, but if you've got the cash, I'd go roller with a Ford racing B303, a set of 1.7 full roller rockers and a set of Howards linkbar hydro roller lifters in that motor instead of chancing a cam failure with a flat tappet cam. You can pickup a used B cam for $60-$80, the lifters will run you another $340. Plus the pushrods, (whatever those will be ?) You can find used roller rockers for $100-150, I'd have the heads converted to screw in studs and guide plates though, no matter the cam. You'll need good springs too.
Yeah, see there's that snowball effect I'm trying to avoid. I know what I WANT to do but each little thing leads to something else and I have to draw the line somewhere if I'm going to drive it any time soon. I think until I'm ready for the next phase I need to keep it down to stuff that works well with what I've got... Which is Comp 942 springs, (339 lb rate) Comp 1.7 roller-tip rockers, and stock pressed-in studs. Which I am willing to pin if I need to... My other alternative would be D8OE heads with pedestal rockers, but those have big ol' chambers.
Well, in this case here, the D8's big ole chambers aren't going to hurt you. They'll help you achieve your goals. With the early 351W heads, the comp ratio is going to be right around 10.5 to 10.8 to 1. Not good to run with the 268H. With the D8 heads, you're going to have slightly smaller valves, but the bigger chambers are going to lower the ratio to a little over 9.6 to 1. Perfect for the 268H. Now you can go this route and save your money for better heads AND a roller cam in the future. Get full roller rockers too. The roller tipped ones you have really don't do much in the way of reducing friction. The ratio helps some, but that's about all. If you'll watch a stock rocker arm in slow motion on the head, the tips are curved slightly and actually roll across the valve stem in motion. The roller tip does almost nothing when you take this into consideration.
Assuming my D8 heads have stock valves, (I haven't checked yet) they're the same size. As for the rockers, yeah, I know they're nothing special. Main reason I got those is for the ratio. There aren't a lot of self-aligning 1.7 rockers out there to choose from, and I figured the 268H could use some more lift at the time I bought them... That and I'd broken a stock rocker once before on those heads so I felt like it needed the strength of the stamped steel vs. the cast stockers. But now I'm wishing I'd got the 1.6's. All the cams suggested to me by Comp's software for my combo are in the neighborhood of .500-.523 lift, and I imagine 1.7 rockers multiplying the lift as high as .556 will yank my studs out. So I'm back to either using the D8 heads for the pedestal rockers, pinning or machining my smaller heads, or maybe prowling the junkyards for some GT40's. I thought that "Thumpr" cam above might be an option too since the lift is relatively low for what it is. But I wonder if the ramp rates and whatnot might be a bit violent for those studs too?
You can give Jon a call at delta cams, I'm not sure if he has the thumpr profiles yet but I know he had all the Ford alphabet cams last time I talked to him. Quoted me $85 for a flat tapped and $100 for a roller. Phone: (800) 562-5500 sales@deltacam.com http://deltacam.com/
Don't happen to know how far the piston is in the hole or what head gasket you're going to use do you? Depending on these two measurements you should come in right at 10:1 compression.
Gasket set is just standard Felpro stuff. It hasn't arrived yet but when it does I'll see if I can find the compressed thickness on it. And the piston vs. deck height I guess I'll have to determine once I start putting pistons in, but I will make note of that measurement before I button it up. :Handshake
Just go get some GT40 heads. Here I can grab a set for less than $100 in the junkyards. And I can get the intakes for about $65 which has to come off anyways. Take the intake home with you and sell it to some mustang guy for $100 and your heads only cost you $65 in the end.
Be prepared. It takes me about 45 minutes to remove an intake and ive done it a couple times now. First one took and hour with a friends help. then to get the heads off most of the front accessories have to come off. Look to see if any special tools will be needed like a fan clutch wrench or pulley puller for he power steering to make things easier. I havent tore down one that far yet on an explorer, just priced them out for future upgrade. but if its 3 hours of work for a set of Gt40 heads that end up costing 60-70 then its time well spent on heads that would normally sell for 200+.
Yep. So I'm looking for '96-'97 Explorers, right? '96 will almost certainly have them, '97 probably will but might not, and I'm looking for three "bars," not four, or check the plug angle if I can't see the end of the head. Correct?
I found this useful reply "Ok another thing you need to know is that the 96-97.5 explorer has the GT-40 iron heads with the f3ze casting like the 93 cobra and they have the same spark plug angle as the e7s and "should" be a bolt on replacement for the e7. these heads have GT stamped all over them and you can identify them because the of the spark plug angle the gt-40p heads look like they just go straight into the head. The intake on the 96-97.5 has the passage for the egr and the heads also have the passage. These are the things i know i got my heads, intake, and throttle body off of a 96 explorer." Here http://www.allfordmustangs.com/forums/5-0l-tech/76769-explorer-gt40-head-q.html Some good info on the differences in the heads in that thread.
Guy here in Houston has a set for sale with a TFS spring upgrade. They are "P" heads. http://htownracing.com/forums/showthread.php?t=53101
I have a set of gt40p heads for sale they have 2.02I and 1.60E the valves are ferrea valves I also have comp cams retainers and hardened keepers I took the springs off and used them on a different set of heads but u can get these for $400 plus shipping (the valves alone were $300)or trade for some other Mav parts
