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We just completed flow testing comparing the stock head to the Ford Racing head.

Stock head at .380 lift 186 IN 144 EX

FR head at .380 lift 217 IN 190 Ex

We confirmed our numbers with another shop. This should help answer some question about this head. We will be dyno testing this head soon in stock configuration and modified. We will be testing Ford Racing parts over the next few months.
 

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You should do a flow chart that plots data all along the lift range. Dollars to pesos says that is where the oversize valves will show their worth.
 

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WIth those huge exhaust flow numbers were gunna have to step down to a smaller exhaust cam
Those ports flow with 20 cfm. 15 % increase on intake and 25% increase on exhaust.... Guess that means were gunna have to run huge power making intake cams to compensate
Stage 4 crowers on intake and stage 3 exhaust or mayby even stage 3 intake on exhaust with stage 4 intake on intake
 

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I am guessing that the high exhaust flow numbers are an attempt to compensate for the flow restriction of the close couple cat.
 

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Most 4 valve heads i have done and flowed tend to flow with less split wetween the intake and exhaust as the 2 valve heads do,meaning the exh, flows with a higher number closer to what the intake number flows (very good for boosted cars)

I dont sell these heads or carry them to sell to me this is the best deal on the market for a ported head for 95% of the guys that are going to do a head swap,,I do feel that the head needs to be surfaced to rais the compression some this will only add to the heads ability to make very good power 795.00 for head and 40 to 50.00 to surface it 840.00

stock head core 100.00
larger valves 225.00
stock valve job 200.00
new seals 25.00
surface head 45.00
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585.00
-840.00 for Ford head surfaced
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thats 265.00 for a full port job and the work needed to install the larger valves

And it leaves you with a head to sell to get about 100.00+ of your money back

These numbers are not set in stone and im sure there are differant prices for differant areas but this gives you an idea why i like it so much looking at the total picture

tom
 

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So how much can you take off the head and have it still be a 100% non-interference design? I would hate to throw down on a head and have a timing belt snap. Those oversize valves are expensive and 16 bent ones would ruin my day.

I know cam selection will make it harder to answer, but any info you feel like sharing...
 

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Well i can tell you at stock non-milled hieght the stage 3 3/4 race cams are definatly interference on exhaust. thats .413 lift.. only .05 hundreths of an inch more then stock hieght. So it would seem like the engine was interference before... if the valve only had to go .05 hundreths farther to hit a piston at tdc. I havent taken it apart but im not so sure if this engine is truly non interfearence. My suggestion would be to make sure your timing belt is showing lots of love when you spin it to 7000
Their is only one type of engine explosion worse then having something move somewhere when its not supposed to... Thats having something not move... like a valve with a cam lob behind it while the piston is moving up the bore faster then bullet. Causes a nasty chain of effects. Get piston all over the place in such sitautions... not to mention what that timing belt would do to your accessories when it came apart at 3500 rpms... All in all change your timing belt when your supposed to and save yourself the trouble
 

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I have Crower stage 1's and they are 100% zero interference as I had the car at TDC and spun both cams, then, put the number 1 intake and exhaust cams at max lift and spun the crank. No problems.

Changing the timing belt is always the right thing to do, but what happens when the belt won't do the right thing for you? I had a 60,000 mile belt go at 25,000 miles. On a BMW. With $33 a piece sodium filled exhaust vavles. Once bitten, twice shy!

I guess I'll have to do some measurements and then have the pistons flycut. You do that, Tom?
 

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Yes we flycut,,but i have never broke a belt and bent all 16 valve the pistons keep moving when the belt brakes but the cams dont ,but yes its still a pain in the butt

Any thing at any time can go bad even a new part

When you are doing performance parst it all part of it

tom
 

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I think it's great for Tom to be praising this head, even though he doesn't sell it. Keep the numbers coming Yel900rr!!!
 

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So basically, it looks as if the right way to do the higher compression thing is to get pistons designed around this head and make sure that they come with big enough pockets to accomodate the valve a max lift. What a PITA. Pistons, rods, head... too much cash.

BTW, my situation is not typical insofar as I thrash the hell out of my car to the tune of 375 miles in just two days while over 5 hours drive from home. At this point, a broken belt and I can still go to work on Monday after a quick swap.
 

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Would this head package work well for a turbo car, as is?

I really like the stainless steel valves, but I wonder about them being 3 angle ground.

Am I right in thinking that they are 3 angle cut?

If so, Tom, isn't this not good for turbo cars? I had heard that since the EGT's are high on turbo cars, that you don't want 3 angle cut valves. Supposedly that reduces the actual contact area on the valve seat, and thus less area to transfer heat out of the valves? Thus, you can actually burn a valve easier?

Does that make any sense?
 

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What about nitrous setups? I have heard raising compression on those setups is not good. Also wondering about cams for nitrous is there special ones or can you use the standard stage II's? Thanks.
 

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P-51 doing a 3 ang. valve job does not change the seat area the other ang. are from the stock seat twords the stem

doing a 3 ang. valve job rounds off the transition area before the seat helping low lift flow mostly

i think these heads will be great for N/A and F/I as well as Nitrous

N/A to me will need to be surfaced to rais compression a little and help boost the power allready in these heads

F/I and Nitrous both like well flowing exhaust and these heads do that

Im not saying these heads are for everyone for a car like mine and a few others some hand work will still be needed but for 95%of the people doing head swaps this to me is the deal

tom
 

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I done the calculations last night with flow numbers on the head (very crude the real calculation of deg*circumfrance area is way too long to not get paid
) an excellent test of this new head would be to try a custom ground 252 dur @.050 cam with a 228 @ .050 crower. That combination is just about right.. Dial in cams at a special travis only known place gotta keep some secrets
and shave .070 off the head. This compression ratio should put your dynamic a little below stock dynamic so you wouldnt have any detonation problems. and idle vacuum should still be around stock levels with that bumped static way up there. Also the cams will be able to be set much more in advance bolstering low end the exhaust cam spread more then advertised that will bolster high end with a sacrifice of mid range... all in all you come off with this head having better lowend then the stage 3 setup on a stock head with stage 3 and a dramatically meaner top end and catch the stock torque curve by 3250 and from there up it would be one hell of a ride. incidentally... larger and larger exhuast cams trade low end for high end beyond this point... midrange remains identicle from this point larger... This head with its massive exhuast flow could really help. Massive gains everywhere however you MUST play with diffrent cam combinations in order to fully realize the overall power with these heads.. Dont slap standard set of cams in this car with those huge exhaust cams youll only sacrifice massive low end torque for a perportionally very small amount of high end power. I do my calculations all on perportions so these are the general trends of these heads. I cant qoute numbers or otherwise however. I can say that a 50 % increase from 4500 rpms to 7750 rpms is realizable with even more at the more extreme high edge.. mayby 75%. With approxiamate 1 % decrese below 3250 to a 15 % decrease over stock engine at 1000 rpms... All in all this head looks absolultly incredible. Larger intake flow then this would be nominal (less then 3% as i figure it) as larger flow then this you would run into other issues. if the port flowed better with more velocity you would be able to run a smaller intake cam with the same top end power but have a larger low rpm torque curve. I cannot Re emphasize the importance of doing lots of homework on cams though.. Camming this head with what aftermarket companies have provided will lead to a less then satisfying ride. Also dont be afraid of those huge static compression ratio`s with these big cams. It all works out you will still be running 87 octane just fine. I think anything higher in compression then this would lead to problems.. 13 :1 or 13:5 to one would put you on 93 high octane however... the gains are small and the chance for things hitting each other is a bit high for my blood. Also cam timing is EXTREMELY important because if you dont get these cams set right your dynamic compression ratio will be incredibly high and cause those evil little elves to be going to work on the top of your pistons. Plug gap and heat should be set at stock as well because of the dynamic remaining pretty much constant.. Well im done preaching for today.
 

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Yea most of my post are gibberish... you gotta read through the bull**** to find teh real info... sorry for the inconvience
Its good info if you can just figure out what the hell im talking about...
 
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