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**GTRacerX** · 07-05-2013, 02:54 PM

I know the stock heads flow pretty well, but are there any good aftermarket heads that flow better or anywhere that can port the stock heads?

re-rx7 · 07-05-2013, 03:03 PM

From what ive read its a tough mision to improve the stock heads.

**46Tbird** · 07-05-2013, 03:53 PM

The stock Coyote head flows more on the intake than Yates Ford Nascar head. Not a fair comparison exactly, since you're comparing two intake ports and valves to one, but it just shows you that they move a lot of air.

No one makes aftermarket heads for these engines yet. A few places will port them but there is a lot more room for making a mistake than there is for improvement. Jeff's heads have a Stage III porting job but I don't know who did them for TSM.

**BLK2012GT** · 07-05-2013, 07:29 PM

Originally Posted by 46Tbird

The stock Coyote head flows more on the intake than Yates Ford Nascar head. Not a fair comparison exactly, since you're comparing two intake ports and valves to one, but it just shows you that they move a lot of air.

No one makes aftermarket heads for these engines yet. A few places will port them but there is a lot more room for making a mistake than there is for improvement. Jeff's heads have a Stage III porting job but I don't know who did them for TSM.

TSM does in house porting now. But I have no clue who they sent my heads to get them done.

**Toby** · 07-05-2013, 07:36 PM

Originally Posted by 46Tbird

The stock Coyote head flows more on the intake than Yates Ford Nascar head.

Crack is a bad thing...

**46Tbird** · 07-05-2013, 10:47 PM

Originally Posted by Toby

Crack is a bad thing...

"The Coyote head at a given lift actually outflows a Yates D3 head." Now that Adam Christian, internal combustion engineering analyst, has your attention, "It's a Four-Valve, right, we're cheating [The radical Yates NASCAR race head is a two-valve.-Ed.], but up to our peak lift, 13mm, we're actually out-flowing the Yates head. And that pretty much means we're outflowing Brand X, Y, and Z."

So you are right, only up to ~.500" lift, but that is still pretty damned respectable.

http://www.mustang50magazine.com/tec...e/viewall.html

**Toby** · 07-05-2013, 11:22 PM

Originally Posted by 46Tbird

"The Coyote head at a given lift actually outflows a Yates D3 head." Now that Adam Christian, internal combustion engineering analyst, has your attention, "It's a Four-Valve, right, we're cheating [The radical Yates NASCAR race head is a two-valve.-Ed.], but up to our peak lift, 13mm, we're actually out-flowing the Yates head. And that pretty much means we're outflowing Brand X, Y, and Z."

So you are right, only up to ~.500" lift, but that is still pretty damned respectable.

http://www.mustang50magazine.com/tec...e/viewall.html

Absolutely, but as you said its not really a fair comparo as both heads are designed in polar opposites in terms of their usage. Also one is a design from the 90's the other is 20 years newer. Take into consideration just a good valve job on a yates head will net 20-30 cfm and it out flows the coyote heads from the word go.

The heads on the new coyote engines are pretty badass out of the box but as with everything, they can be improved. Although not very cost effective when compared to nitrous or boost, when you are dealing with only 302 ci, the power number gain may not be much, but look at it on a % gain. When you can do basic hci on a coyote and make damn near 500 rwhp with a stock bottom end, that computes roughly 1.6 hp/ci thats fucking huge!!! Technology has improved so much in the past few years its crazy! I am in the process of putting together an engine package for a dirt track car. Plans are to run 302 ci old school sbf and get around 400 fwhp using stock bottom end, stock iron heads with 0 port work allowed and only using a 380 cfm carb.... talk about a challenge.. haha

**GTRacerX** · 07-05-2013, 11:23 PM

So basically at this point the cost doesn't outweigh the performance gain?

re-rx7 · 07-05-2013, 03:58 PM

So basically Port the Exhaust side and leave the Intke alone?

**46Tbird** · 07-05-2013, 04:01 PM

No, leave them completely alone and find other ways to build power. Unless you're trying to set n/a Coyote records...

re-rx7 · 07-05-2013, 04:03 PM

Originally Posted by 46Tbird

No, leave them completely alone and find other ways to build power. Unless you're trying to set n/a Coyote records...

What about a valve job? 5 angle?

**Toby** · 07-06-2013, 08:45 AM

You will pick up 20-30 hp with ported heads

**Yagermeister** · 07-24-2013, 01:19 AM

Jeff did you ever get any flow numbers for your heads? I may be interested in sending mine out. Also did you upgrade/change the valves, seals, etc.?

**BLK2012GT** · 07-24-2013, 01:22 AM

Originally Posted by Yagermeister

Jeff did you ever get any flow numbers for your heads? I may be interested in sending mine out. Also did you upgrade/change the valves, seals, etc.?

Ill see if TS got those numbers.

**Yagermeister** · 07-24-2013, 01:23 AM

I wouldn't be doing it until the winter but it would be good to start getting my plan in place. Thanks!