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Ooops! did it again.... RIP Coyote....

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Mad Hatter

Gotta go Faster
5,237
4,227
Santiago, Chile
Well parts are arriving soon for build 3.0... Bottom end will be the same K1/Wiseco setup and had the crank magnafluxed it came up fine. For the heads, we are doing a full porting with valve a job with 37.3 and 31.8mm valves. The stock untouched heads are ugly compared to the Boss heads but they seem to working out so far.

The initial gen1 head flow numbers are about 280cfm at 0.500 lift and approx 290 cfm for the boss heads at the same lift. My nutty builder wants to get them to 330 cfm at 0.500 which would be fantastic, So far we have 315 cfm and nice numbers at lower lift as well, getting to 320cfm would be fine by me. Truly amazing what you can do with a good anemometer, a industrial vacuum cleaner and a head bench! Ahh, and of course the secret sauce of someone who loves porting heads and has been doing it for a while. Once we get to the max possible value, he will use templates and testing to get to the same values for all the other ports. Using the dead boss head as the trail horse for the changes, So, at this rate the heads will be ready in a couple of weeks. Which means we can build the bottom end slowly and carefully.

Once the heads are done, they will be topped off with a VMP Dual 67mm TB with Cobra jet manifold and a JLT CAI. The LM intake only cams where saved from the Boss heads. Would really like to get to 470rwhp if possible. And to top it all off an updated AED race tune.

😅
This time around will keep the rpms to 7800rpm max and watch the down shifts.
 
1,289
1,113
Exp. Type
HPDE
Exp. Level
5-10 Years
Philly Metro Area
As a frame of reference, here is Livernois' advertised flow for their heads. Click on the product info tab for flow rates:





 

Mad Hatter

Gotta go Faster
5,237
4,227
Santiago, Chile
Thanks Coz.. with the LM cams we would only get to 0.513 Lift but that would be fine.
 
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Mad Hatter

Gotta go Faster
5,237
4,227
Santiago, Chile
Since my builder/friend has been heaping lots of cruel jokes at me for my lack of understanding of the finer points of porting heads. Have been studying so I can lower my putz factor when I go visit my car in his shop.

At first I kept asking him about how are we going to get more cfm so we can match the advertised cfm figures you can find online. His answer was air velocity first, and cfm comes after. His goal was to increase cfm AND air velocity.... Most of the porting jobs down here are just making the ducts bigger and concentrating on max flow but ending up with a drop in velocity. So far we have a 6% increase in velocity and flow over the Boss head with the ported gen1 stock cast heads.

Found a interesting article.... https://www.enginebuildermag.com/2016/10/flow-bench-testing-is-more-than-cfm-numbers/

The only problem is that it takes for ages (and a day) to hand port a head!!! Almost six weeks so far. With a bit of luck they will be ready on Monday. I have my base AED tune from Shaun ready to go and can't wait to break her in and log the car for the final tune..... and see what all this work does on the dyno!! Hoping for 465rwhp.

First race is on the 27/28th of March. Counting the days!!!
 

Grant 302

basic and well known psychic
At least you’re learning! 👍

If you have any of the ‘dead’ heads around...might be good to let him chop them up. Unless he already has some coyote head cutaways. I always took the opportunity to handle and feel the ports when possible. I still have one of the 2V ‘PI’ head sections from my last porting project almost 20 years ago.

Good luck getting it all back together!
 

Mad Hatter

Gotta go Faster
5,237
4,227
Santiago, Chile
Just talked to the shop and he has managed to get the velocity up by 19% and CFM by 12% over the boss heads, so thats over 330cfm!! . Does this mean I need to upgrade the injectors to a larger size?? Was thinking of going from the stock 34 lbs/hr to 46 lbs/hr. The car will be ready just in time for the end of March race but did not want to have any last minute problems.
 

Mad Hatter

Gotta go Faster
5,237
4,227
Santiago, Chile
Well got the email back from Shaun at AED today.... No need for bigger injectors.. Though he did say that at the flow rates the head is getting, the bottle neck will be the Cobrajet manifold!! Very curious to see the results.....

I guess we need to port that as well!!
 
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9
2
Exp. Type
Autocross
Exp. Level
10-20 Years
Detroit and dallas
I don't know how heavy they are but the Gen2 does rev higher than the Gen1 and closer to the Boss.

This is a good reference regarding the differences across the generations of the Coyote.

https://performanceparts.ford.com/download/pdfs/Gen_2_Coyote_Technical_Reference_2-16.pdf

Unfortunately, while it refers to improvements to the Gen2 that were inspired by the Boss, it doesn't have a separate column for it.

I believe among the differences is that the Boss head was a slightly different alloy with more copper for heat dissipation. Also, the comparison column states that the Gen1 intake valves are hollow and exhaust valves are sodium filled. I thought they were solid and only the Boss had the hollow/sodium valves.
I think it's cool that people are finally talking about this and noticing this I mean every time I hear somebody say oh the Gen 2 heads are basically boss heads no they're not they're a different metallurgy they're lighter Valve they have sodium filled exhaust valves which makes them heavier the boss was built specifically to run and rev like crazy (I own one) and they have different valve springs and you know the boss springs they're only good to 8000 RPM,and they never intended to revving to 8,000 when you get to 8,000 you're flattening them out possible coil bind, everybody says look the coyote rev so high and it's a tough engine and it'll put up with it for a long time but the boss to go from 7,000 or 6,800 RPM to 7400, took some doing they eliminated the oil squirters so they had to have forged pistons, at a certain point you begin to double and triple the stresses on crankshafts rods etc I don't know what that is on the coyote but I do know this is true the boss was specifically made to rev to 7400 it wasn't just oh raise the rev limiter it's cool. You're right it's lighter Valve drain it's a different balance on the on the internals of the engine it has different bearings in the crankshaft they call them race spec bearings they're not aluminum they're probably some sort of try metal or lead and the 5w50 oil that's a direct response to 7400 RPM there's a really great article I've got that was the engineering article about 7 months after the development of the coyote they were asked to build a hypo version which became the boss and I've got the engineers documents and what they had to do it's quite extensive everybody that just wants to take a GT and just let's just turn off the rev limiter and see how far it'll go it'll put up with it but there's a lot of tuners that tune engines and they say when people begin to do that within the year especially if they're tracking the car and revving it like that the GT engine will not last they usually smoke in an engine within that season. Run it out was designed I say.
 
6,363
8,190
I think it's cool that people are finally talking about this and noticing this I mean every time I hear somebody say oh the Gen 2 heads are basically boss heads no they're not they're a different metallurgy they're lighter Valve they have sodium filled exhaust valves which makes them heavier the boss was built specifically to run and rev like crazy (I own one) and they have different valve springs and you know the boss springs they're only good to 8000 RPM,and they never intended to revving to 8,000 when you get to 8,000 you're flattening them out possible coil bind, everybody says look the coyote rev so high and it's a tough engine and it'll put up with it for a long time but the boss to go from 7,000 or 6,800 RPM to 7400, took some doing they eliminated the oil squirters so they had to have forged pistons, at a certain point you begin to double and triple the stresses on crankshafts rods etc I don't know what that is on the coyote but I do know this is true the boss was specifically made to rev to 7400 it wasn't just oh raise the rev limiter it's cool. You're right it's lighter Valve drain it's a different balance on the on the internals of the engine it has different bearings in the crankshaft they call them race spec bearings they're not aluminum they're probably some sort of try metal or lead and the 5w50 oil that's a direct response to 7400 RPM there's a really great article I've got that was the engineering article about 7 months after the development of the coyote they were asked to build a hypo version which became the boss and I've got the engineers documents and what they had to do it's quite extensive everybody that just wants to take a GT and just let's just turn off the rev limiter and see how far it'll go it'll put up with it but there's a lot of tuners that tune engines and they say when people begin to do that within the year especially if they're tracking the car and revving it like that the GT engine will not last they usually smoke in an engine within that season. Run it out was designed I say.
The rev limiter is your friend. So is an Accusump.
 

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