Head Change on new Ford 345HP crate engine

[outlaw66]

Have a question about possibly changing heads on the new Ford crate engine I just purchased. Then heads are the X 303 GT40 heads with 1.94 intake and 1.54 exhaust valves and all I can find other than that is "they flow significantly better than the 5.0 heads". I also have a new set of "Jegs" 58 cc heads with 2.02 intake and 1. 60 ? exhaust valves, 170 cc intake runners. Will these heads be an improvement over the GT 40 heads? The compression on the engine is 9.1 but I have no idea what combusion chamber volume is on the GT 40 heads. The Jegs heads were rated up to .580 lift I believe. The roller cam in the crate engine is adverstised at 224 @ .50 and .480 lift. Can I and should I change the heads and what about an upgrade on the roller cam..more lift / duration? This is in a street car with occasional trips to the track. I do not know if the Hypereutectic pistons in the engine even have valve reliefs, nor the max lift based on piston/valve clearance. I have the same engine in a Cobra kit car and it runs great but I wanted to increase the HP on the engine for use in the Mustang. I'd appreciate some feedback on the head change and possible camshaft upgrade?

Outlaw66

 

[D.Hearne]

The GT40X heads can be either 58 or 64 cc. Look at the part number. X303 is 64 cc, X305 is 58. You've got a B303 cam in there. If the Jegs heads are the Kasse/Jegs ones, you should have no piston to valve clearance issues. Your pistons do have valve reliefs, but with std inline valve heads, they won't be able to clear 2.02 valve heads with some cams. I doubt you'd have trouble with the B cam.

 

[jikelly]

I was thinking maybe you should do a cam swap. A lot of people say the B303 cam is a flop, but there are others who have one and are happy with them.

I would kinda say keep the xheads and swap out the cam for the E303. I actually am swaping out the 5.0 stock cam in my new shortblock for Trick Flows stage 1 cam. I'll add 1.7 rockers later to get a little more lift and faster acceleration of the valves to their fully opened position.

Actually you could send me the heads. I'll cover the shipping cost.

Small Ford: 1985-95 302, 5.0L (with roller tappet cam), 1994-95 351W (with factory roller cam when used with mass air EFI), 282/282 degrees duration, hydraulic roller camshafts


Advertised duration: 282 intake/282 exhaust
Duration at .050 in. cam lift: 220 intake/220 exhaust
Gross valve lift: .498 in. intake/.498 exhaust
Lobe separation: 110 degrees
Peak horsepower rpm: 5,500
Peak torque rpm: 2,500
Good idle

 

[10secgoal]

It'll void your waranty if you care. Ford is real strict with their crate motors. They tell you what intake and gasket to run. The timing, and you have to have proof of tuning. You must have all this, or warranty is void

 

[CochinoFilipino]

GT-40 Y's: Aluminum, 1.94 int./1.54 exh. 160cc intake runners. 53cc exh. runners. 64cc chamber
GT-40 X's: Aluminum, 1.94 int./1.54 exh. 178cc intake runner, 62cc exh. runner. 64 or 58cc chamber.

 

[D.Hearne]

I was thinking maybe you should do a cam swap. A lot of people say the B303 cam is a flop, but there are others who have one and are happy with them.

I would kinda say keep the xheads and swap out the cam for the E303. I actually am swaping out the 5.0 stock cam in my new shortblock for Trick Flows stage 1 cam. I'll add 1.7 rockers later to get a little more lift and faster acceleration of the valves to their fully opened position.

Actually you could send me the heads. I'll cover the shipping cost.

If you're going to swap cams, an E cam isn't what you'd want. Ford rated both at the same output in that engine.

 

[outlaw66]

Thanks guys, the crate has the X heads and the B cam, I was just wondering if replacing the heads would be worth the effort in HP gains and if so would the B cam be the best grind with the Jegs heads. The heads are NOT the Jegs/Kasse heads available now. I got these only about 3 months ago and at that time the Jegs/Kasse heads were not available or at least I didn;t know about it. Just trying to evaluate if the HP gains would be significant or not. I plan on running the Edlebrock 2X4 intake. As mentioned earlier, I have the same engine in a Cobra, just wanted a little more power if changing heads was worth the effort.
With a cam swap, I don;t want any piston/valve problems and do not know what the max lift this engine will support with the Jegs heads and the Hyper pistons.

And Gee thanks KI....thats mighty nice of ya to offer to pay the shipping. Let me think about that a while, after all I don;t have that much time till the asteriod hits in 2036.

Outlaw66

 

[D.Hearne]

Go look these heads up on Jeg's website. They say there, they're OK with up to a .550 lift cam with stock pistons (but actual results can vary, this is my advice) They also recommend a cam for maximum output that's probably not a B303 cam. Total valve lift is only part of the equation in piston to valve interference. The actual timing events also comes into play. Which is why you really should check for interference or clay a piston top before trying to run a close to max head/cam/piston combo.

 

[outlaw66]

Thanks D....But is the head swap a performance enhancement? I thought that with the heads and another camshaft with a little more lift/duration I should be able to bump the HP up another 25-30. Since I already have the heads and the engine is not installed, changing heads and checking piston/valve clearance is relatively easy. And I also realize that there is more involved than lift alone and would ensure the lift was not extreme. And you're right, the heads advertise .580 max which is considerable compared to the B cam's .480. I'll have to go back and check the specifics on the cam recommendation provided by Jegs.
Thanks again for your insight.

Outlaw

 

[D.Hearne]

You'd could very well realize a 25-30 hp improvement with just a cam swap with the X heads. The B cam is a really small cam to start with. I've used one but added 1.7 rockers to give it a bump in lift. If swapping cams, I'd go with the maximum cam the heads and springs allowed. That's basically what I did with my 331. Went with a Z303 on it, it was the best bang for the buck, bought it NIB second hand for $115 here on the SN classifieds. I figured it to be a wild cam going by Ford's description, but it's actually quite streetable in the 331 with the dual plane 3x2 setup feeding it. Idles at 6-700 rpms and power comes on at 1500.

 

[outlaw66]

so whats your opinion about swapping the heads? I agree on the B cam, and sure would like to move up on duration/lift. Is there a good source to find out some limitations on this engine with respect to lift? I have all the Ford advertised stuff but of course they don't provide any info regarding upgrades. I plan on running all the stock lifters and pushrods. I do have a set of Comp roller 1.6 rockers but its for 7/16 studs and I don;t remember what the stud size is on the crate motor. As always thanks for the knowledge and time.

Outlaw

 

[spade33]

i got it ....ill take one of the pair of heads off ur hands and u can choose the left over pair! haha

 

[outlaw66]

so which pair do I get?

outlaw

 

[67Dylan]

IMO, keep the heads, upgrade the springs (EdC ramp rates are pretty aggressive) and order a custom cam. The alphabet soup cams are OK, but very antiquated IMO; not saying they won't work, just that there are better cams on the market. Order one from Buddy Rawls or Ed Curtis and you'll be happy. I'm not a fan of those heads, but they will work for your application.

BTW, what size motor? I didn't see it anywhere.

 

[302 coupe]

A lot of people say the B303 cam is a flop...swap out the cam for the E303. I actually am swaping out the 5.0 stock cam in my new shortblock for Trick Flows stage 1 cam.

every cam you just mentioned is a flop. Anyone who says any letter cam, or any trick flow cam is even decent, has no business giving cam advice. I would use the stock cam long before an "upgrade" to any of those cams.

 

[jikelly]

every cam you just mentioned is a flop. Anyone who says any letter cam, or any trick flow cam is even decent, has no business giving cam advice. I would use the stock cam long before an "upgrade" to any of those cams.

Oh I guess you assumed I knew what I was talking about.

I fully admit my knowledge if roller cams is limited, but based on the information given by Stangnet members in the following thread http://forums.stangnet.com/showthread.php?t=684966 I chose the trick flow cam. It's the one I'm going to use. Sure I'd of liked to've gotten the comp cam, but it was way more than the TFS1 cam I got for 100 bucks new off ebay.

 

[302 coupe]

So long as you're satisfied with it, I guess thats all that matters. Personally, it would bug me to know I was leaving considerable power on the table.

PS. Sorry if my prior post was harsh, I'm posting from work, so I may/may not be in a good mood, lol.

 

[bnickel]

persona;;y, i'd start with just a cam swap and leave the heads alone. the X heads are a decent head and have a pretty efficient chamber. are they the best heads out there? probably not, but i'd bet they are pretty equal to the Jegs head or at least not far behind them. if you decide against the X heads i'd be interested in buying them if you want to get rid of them, i'd like to have them for my next engine build on a mild 351w.

 

[C0V3R]

Whats wrong with the TFS cam?

 

[D.Hearne]

every cam you just mentioned is a flop. Anyone who says any letter cam, or any trick flow cam is even decent, has no business giving cam advice. I would use the stock cam long before an "upgrade" to any of those cams.

Have you ACTUALLY run one, then swapped just the cam out for an expensive custom grind? And after the swap, did the power you were "missing" register on the seat of the pants meter? I've run both the B & Z and both can't be beat for the price. Second hand B cams can be had for $75, I bought the Z cam new for $115. Both work great. Even the F4TE truck cam works great with 1.7 rockers. In fact, it's the best cam I've ever run with a carb, even though it was never intended as a carb cam.