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Old 10-06-2014, 05:44 PM   #201
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Would you still recommend +2 for turbo too? It's odd as talking to a few boosted local gurus (drag racing, 5,000+ HP) they keep the exhaust valve small for velocity reason... What are your thoughts on that?
I had a similar conversation with the guy that has been doing my heads over the years. One size certainly does not fit all when it comes to the various forms of forced power adding and N/A.

I have heard that you go smaller on the exhaust port on turbo motors. I can't recall the conversation when it comes to the actual valve though. For some reason I recall the port size and shape was what was more important on a turbo motor.
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Old 10-06-2014, 06:07 PM   #202
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I am already eyeing this for the race car. I did port the head; the amount it was ported I am sure there is some inconsistencies between the ports, and the valves and all that are stock. Originally wasn't planning to go over 7,000 but why not if I can. The cams you guys have are probably not boost-friendly? Would you still recommend +2 for turbo too? It's odd as talking to a few boosted local gurus (drag racing, 5,000+ HP) they keep the exhaust valve small for velocity reason... What are your thoughts on that?
Additionally what sort of a cost increase for ceramic coating? How has been the longevity of the coating? We have had some uber-failures on rotaries with the ceramic coating on the rotors...
1. Take what the V8 drag racers tell you and toss it out when it comes to BP motors. Read our website recommendations again. +2 exhaust specifically recommend for F/I or high output cammed N/A motors (180whp+)

2. We do not offer coating as an option. Done correctly, it's magic and lasts. We could start a new thread about coatings.

3. Cam assumption would be incorrect in this case. The cams were are currently offering are relatively short duration. Long for street but way short for a race engine. Intended to keep torque peak at or near OEM RPM point with STB manifold. Same cams we are currently running in Deviate with a Rotrex (10psi/304whp). To keep a nice idle, we like to stay at 260 seat duration or shorter. Past that street manners begin to depart the scene. If you don't car about idle, are doing forged everything, billet damper, oil pump gears, etc, get custom cams up around 285 seat N/A. Below that F/I.
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Old 10-06-2014, 06:21 PM   #203
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And my builder finds the flow on the exhaust side large enough with stock size valves when using +1mm intake valves. Aiming for reasonable similar duration of the cams.

Attention: This is my head, not the CNC head.
But I have not played around with enough different cams to figure out if it's a limitation, yet, if I ever will know what's perfect.

There are many guidelines and theories, but only the ones testing a lot of combinations build the knowledge to start in a decently happy place.
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Old 10-06-2014, 07:19 PM   #204
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And my builder finds the flow on the exhaust side large enough with stock size valves when using +1mm intake valves. Aiming for reasonable similar duration of the cams.
Every head specialist and engine builder will have their own idea of what "enough" intake vs exhaust flow is.
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Old 10-06-2014, 08:37 PM   #205
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1. Take what the V8 drag racers tell you and toss it out when it comes to BP motors. Read our website recommendations again. +2 exhaust specifically recommend for F/I or high output cammed N/A motors (180whp+)

2. We do not offer coating as an option. Done correctly, it's magic and lasts. We could start a new thread about coatings.

3. Cam assumption would be incorrect in this case. The cams were are currently offering are relatively short duration. Long for street but way short for a race engine. Intended to keep torque peak at or near OEM RPM point with STB manifold. Same cams we are currently running in Deviate with a Rotrex (10psi/304whp). To keep a nice idle, we like to stay at 260 seat duration or shorter. Past that street manners begin to depart the scene. If you don't car about idle, are doing forged everything, billet damper, oil pump gears, etc, get custom cams up around 285 seat N/A. Below that F/I.
1. Fair enough. I wasn't questioning your stuff, just asking opinion. I am aiming for the 575-600hp (we shall see). The engine is built and running with the turbo. The car is still waiting a few things before it gets on the track.

2. That sounds good. How have they held up with you guys' experience though? It would be nice to keep all the heat where it is needed.

3. Alright, so for a race only (talking 4,500-5000rpm and above) would you still recommend those cams?

Thanks again for taking the time to reply!
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Old 10-06-2014, 09:56 PM   #206
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1. Fair enough. I wasn't questioning your stuff, just asking opinion. I am aiming for the 575-600hp (we shall see). The engine is built and running with the turbo. The car is still waiting a few things before it gets on the track.

2. That sounds good. How have they held up with you guys' experience though? It would be nice to keep all the heat where it is needed.

3. Alright, so for a race only (talking 4,500-5000rpm and above) would you still recommend those cams?

Thanks again for taking the time to reply!
2. Answered that unambiguously I thought
3. Over stock, absolutely. Over custom-for-your-build cams ground by a specialist who knows boosted BP race engines, no.
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Old 10-06-2014, 10:38 PM   #207
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$5k Ain't bad for this at all. I'd rather have a CNC's cammed head than a turbo...
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Old 10-07-2014, 01:31 AM   #208
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2. Answered that unambiguously I thought
3. Over stock, absolutely. Over custom-for-your-build cams ground by a specialist who knows boosted BP race engines, no.
2. sorry I had seen pictures of one or two head with coating and though you might know how they held up, not that you did it yourself.

Alright. Have to put the money together and then bug you!
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Old 10-07-2014, 01:34 AM   #209
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everyone trying to reinvent the work Emilio has already done. Go ahead, spend a bunch of money trying to do things your own way. It will not be as good, you will sell, and end up spending double the money buying a head from emilio because you didnt do it right the first time.
He hasnt just guessed at this. Its been many years of development in the making. I dont care how experienced or reputable your engine builder is. They dont necessarily know how to optimise different individual head designs without some development and design evolution. They are salesmen with pride and will tell you they can however.
I had a no excuses $5k head built by another very reputable builder for my last bottom end. It made 184whp 136ft/lbs with 300 duration .500' lift cams and TWM ITBS.
Now I have Emilios CNC head with +1 valves, stock cams, stock vics manifold on an identical bottom end and it makes 175whp/ 144tq. and its a super fat powerband
do it once, do it right.
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Old 10-07-2014, 02:23 AM   #210
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2. sorry I had seen pictures of one or two head with coating and though you might know how they held up, not that you did it yourself.

Alright. Have to put the money together and then bug you!
I think I understand your confusion. I answered thus: "Done correctly, it's magic and lasts". I would not state anything like that without DPE (direct personal experience). IOW, that is not conjecture or something I read on the interwebs
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Old 10-07-2014, 02:13 PM   #211
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I think I understand your confusion. I answered thus: "Done correctly, it's magic and lasts". I would not state anything like that without DPE (direct personal experience). IOW, that is not conjecture or something I read on the interwebs
Alright! I am going to rephrase my question : Would you happen to know someone that can do it correctly that you can send the head to once I purchase it? Thanks!
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Old 10-07-2014, 02:42 PM   #212
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Alright! I am going to rephrase my question : Would you happen to know someone that can do it correctly that you can send the head to once I purchase it? Thanks!
That info is proprietary, sorry. We may offer coated chamber/exhaust port/valve heads as an option.
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Old 10-07-2014, 04:50 PM   #213
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Oh my god... seriously! I don't want the person's info, I was asking if I order the head, you can have it coated by your magic super secret person or I will have to chase people down myself. Which sounds like you can.
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Old 10-07-2014, 06:36 PM   #214
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Our CNC head includes a deshrouded chamber. The best flowing BP head I have ever heard of is our +2.
I took that as a given. Just wondering if the walves might be getting so large that extra deschrouding and a camfer on the cylinder wall might give extra HP?
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Old 10-07-2014, 07:02 PM   #215
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I took that as a given. Just wondering if the walves might be getting so large that extra deschrouding and a camfer on the cylinder wall might give extra HP?
"I wonder if you optimized it or just stuck bigger valves in there?"

It is optimized
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Old 10-07-2014, 07:17 PM   #216
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"I wonder if you optimized it or just stuck bigger valves in there?"
Not at all.
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Old 10-07-2014, 09:10 PM   #217
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Not at all.
Just wondering if the walves might be getting so large that extra deschrouding and a camfer on the cylinder wall might give extra HP?
Chamfering the block would be a very large mistake.
The chambers are deshrouded to match the valves.

Your basic question seems to be whether there are additional gains to be found with our head by modifying it after purchase or us redesigning it for the +2 exhaust valves. What I am stating is that we thought of that, and modify the chambers for the +2 valves. They are dialed as well as they will get and are deshrouded out to 85.0mm. 85.5 pistons will have .25mm (.0098") overlap from cut to wall.

The very concise answer to your original version of the question is "No".
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Old 12-23-2014, 09:51 PM   #218
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Default 180whp 152tq N/A

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Old 12-24-2014, 12:38 AM   #219
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I saw that on facebook, god almighty. Glorious build. I love that everything is OTS and within reach of us peasants. I have this image of you walking through the shop going "and that, and that, and that..."
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Old 12-24-2014, 12:39 AM   #220
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Nooooooo! (To deviate not being boosted)

Yesssssss! (To that dyno graph and what you're getting out of a bulletproof N/A motor)

-Ryan
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