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Old 03-31-2008, 08:02 PM   #1
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Default Basic head porting/5 angle valve job. Gains?

So I am thinking of getting my heads worked over. My shortblock will be done soonish, and I want to breath a little better.
I am looking at having a run of the mill port/polish with the flow bench, and a 5 angle valve job.

I would be retaining the OEM cams, springs and valves. I want more power, but I am not looking for sky high RPMs and I am on a definate budget at this point.
Really what I am looking for is more efficiency, more power at lower stress levels on the motor (less boost, nice and safe a/f and no crazy timing)


SO..

What am I looking at in terms of gains? And where would they be?
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Old 03-31-2008, 08:14 PM   #2
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why port the engine heads if your not going to be pushing more air through them? Seriously, you port to create more air and also better air flow, why not turn up the boost? Spend that money on something else like a better tmic/y pipe, a retune, or something.
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Old 03-31-2008, 08:55 PM   #3
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There will be PLENTY of air

This is a built shortblock, GT30R .83, FMIC, blow through maf (tuned on speed density though) TGV deletes, header, meth injection.
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Old 03-31-2008, 09:35 PM   #4
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Powerband will shift to the right and you'll gain ridiculous topend. IF you do manage to push enough air thru them, those stock cams will probably offset any great gains. But if you're going to do cams later, might as well do the port work now.
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Old 03-31-2008, 11:13 PM   #5
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-here's some flowtest data--tested CFM at 25" test pressure.

TEST 1-is stock, used & carboned up a little but fairly clean, used valves & seats.
TEST 2-ported pretty decent but to suit stock valve sizes---no valve job preparation yet.

valve---------------test 1-------------------------test 2--------------
--lift------int-2-exh------int-4-exh---------int-2-exh------int-4-exh
.100----87.2--73.4-----87.5--72.8--------87.4--70.2-----87.7--70.0
.200---164.5-149.2----165.7-142.1-------164.5-154.7---163.7-158.0
.300---219.1-174.8----220.6-161.1-------221.0-202.7---223.8-189.0
.350---228.5-180.8----226.9-165.6-------237.0-221.8---235.7-203.3
.400---234.8-184.5----230.7-167.8-------245.2-233.4---247.4-209.1

-this is a typical comparison of what I see with B25 heads.

-One issue about doing the trick 5 angle valve seats is that requires sinking the valves into the heads which means now you have to deal with the expense of changing cam followers because the valve lash will be too tight.

-The valve job can be worth a little when using stock size valves----but the porting is worth a lot more----especially if you can perk the exhaust up like this ported example.

-Oversize Intake valves can be worth another 20 CFM with a machined 3 angle valve seat----but the exhaust rarely ever exceeds what can be had with stock valve sizes.

-The main reason that oversize exhaust don't respond or seldom ever exceed the flow obtainable with stock size exhaust valves is that you have to open the valve bowls too large and blend from the seat up to the crest of the floors----and when you start thinking you are getting somewhere with the exhaust flow you end up grinding thru into the water jacket---especially on the rear exhaust port of the doglegged pair like Cylinder #4.

-When this happens you need to know some guy who is well experienced at welding up inside that tiny little port where you actually can't even see the hole you are needing to weld up.

-A typical intake valve seat job of a 45/60/75 intake angles with the chamber fluffed and buffed right to the top of 45 and the bowls blended up to nearly the bottom of the 60--basically just leaving the 75 degree demarcation line----and having the 45 and the 60 each about .070" wide works pretty decent---and can be fairly easy to do.

-The exhaust does NOT ever want angles or demarcation lines----just a 45 with a nice perfect hand blended roll into the bowl--and just slightly enlarge the bowls.

-Probably the most important deal with the seats and when using stock valves---is to get the runout out of the seats----and get the seat diameter out to the outer edge of the valve 45 degree faces----with the minimum amount of seat depth loss.

-If the intake seat ends up too wide narrow it up with 60 on the bottom and something like 22 if you have to touch the top.

-when the exhaust needs to be narrowed at the bottom (down in the bowl) I have found it best to always use something like a very light cut with 52 or maybe a 54 degree.
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Old 04-01-2008, 12:25 AM   #6
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I would do mild cams on the stock heads before doing ported heads with stock cams, but that's just me. I just barely fit headwork+cams into my budget and was really happy with the results. I have a feeling most of the benefits were from the cams, but wow, it's like a totally different car. MAF volts just keeps increasing till redline, and at redline the stock motor needed a couple psi more boost to keep up. It was money well spent. I had +0.5mm supertech stainless valves installed w/ti retainers, dual valvesprings, and cosworth 278/274 avcs cams. stock ports with reshaped valve bowls.

If you "do it right" you will need to upgrade your fuel system
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Old 04-01-2008, 12:36 AM   #7
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Quote:
Originally Posted by fwillyj View Post
-here's some flowtest data--tested CFM at 25" test pressure.

TEST 1-is stock, used & carboned up a little but fairly clean, used valves & seats.
TEST 2-ported pretty decent but to suit stock valve sizes---no valve job preparation yet.

valve---------------test 1-------------------------test 2--------------
--lift------int-2-exh------int-4-exh---------int-2-exh------int-4-exh
.100----87.2--73.4-----87.5--72.8--------87.4--70.2-----87.7--70.0
.200---164.5-149.2----165.7-142.1-------164.5-154.7---163.7-158.0
.300---219.1-174.8----220.6-161.1-------221.0-202.7---223.8-189.0
.350---228.5-180.8----226.9-165.6-------237.0-221.8---235.7-203.3
.400---234.8-184.5----230.7-167.8-------245.2-233.4---247.4-209.1

-this is a typical comparison of what I see with B25 heads.

-One issue about doing the trick 5 angle valve seats is that requires sinking the valves into the heads which means now you have to deal with the expense of changing cam followers because the valve lash will be too tight.

-The valve job can be worth a little when using stock size valves----but the porting is worth a lot more----especially if you can perk the exhaust up like this ported example.

-Oversize Intake valves can be worth another 20 CFM with a machined 3 angle valve seat----but the exhaust rarely ever exceeds what can be had with stock valve sizes.

-The main reason that oversize exhaust don't respond or seldom ever exceed the flow obtainable with stock size exhaust valves is that you have to open the valve bowls too large and blend from the seat up to the crest of the floors----and when you start thinking you are getting somewhere with the exhaust flow you end up grinding thru into the water jacket---especially on the rear exhaust port of the doglegged pair like Cylinder #4.

-When this happens you need to know some guy who is well experienced at welding up inside that tiny little port where you actually can't even see the hole you are needing to weld up.

-A typical intake valve seat job of a 45/60/75 intake angles with the chamber fluffed and buffed right to the top of 45 and the bowls blended up to nearly the bottom of the 60--basically just leaving the 75 degree demarcation line----and having the 45 and the 60 each about .070" wide works pretty decent---and can be fairly easy to do.

-The exhaust does NOT ever want angles or demarcation lines----just a 45 with a nice perfect hand blended roll into the bowl--and just slightly enlarge the bowls.

-Probably the most important deal with the seats and when using stock valves---is to get the runout out of the seats----and get the seat diameter out to the outer edge of the valve 45 degree faces----with the minimum amount of seat depth loss.

-If the intake seat ends up too wide narrow it up with 60 on the bottom and something like 22 if you have to touch the top.

-when the exhaust needs to be narrowed at the bottom (down in the bowl) I have found it best to always use something like a very light cut with 52 or maybe a 54 degree.
This is great info. Thank you,
Charliew
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Old 04-01-2008, 12:42 AM   #8
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I would at least go for the sti cams and the valve seat and port work if you are using a 2.5. If the shop is good enough to do the 5 angle they can probably shorten the stems to use the buckets you have.

Wittmer 25 has the 30r and BC .421 lift cams with stock size valves and mild porting (260 cfm at .450 lift)
and his 100mm bore 2.5 sti pulls real hard on 93 octane. and 25 lbs. boost but it does run out of steam about 7k. His low end did improve after the cams and porting. The car sounds about 30% louder with the same exhaust as before with the new 100mm bore and porting and cams and of course a new tune and upping the boost from 18 to 25lbs.
Now if we could just fix the high rpm scratching in 5th.
Charliew

Last edited by charliew; 04-01-2008 at 02:35 AM.
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Old 04-01-2008, 01:57 AM   #9
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The 07 motor has the same cams as the STI already.
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Old 04-01-2008, 02:40 AM   #10
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Sorry I'm not up on 07 subies. I would rather go with better cams than just a valve job. When you decide to get better cams you'll have to go back an do the clearances over just like from the valve job. You probably won't do the cams unless you do them now. Unless the worst happens.
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Old 04-01-2008, 12:48 PM   #11
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hmm....

A lot to think about. 16 new buckets wouldnt be so expensive (well, its a big chunk to add on top of an already wallet crushing mod) I would do cams and the porting all at once.

Maybe Ill just do cams instead.

Would I see similar gains from cams only, as I would from porting only?
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Old 04-01-2008, 01:08 PM   #12
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Any decent head shop can grind down the valvestems. I only ended up needing one new bucket, and my shop had a grenaded motor that they were able to snag a bucket from.
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Old 04-01-2008, 02:57 PM   #13
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Ahh I didnt even think of that.
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Old 04-01-2008, 07:45 PM   #14
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I am interested in who you use if you do go the 5 angle in the austin area. I haven't looked hard in waco but my favorite place didn't have the right size cutter for the multiangle I may check into buying the cutters myself and doing my own but I would rather not invest in them if you find a shop where the quality and price is right. I think the cams will show more top end and low end performance than just the porting.

I drove my sons car to the subie dealer in temple from waco today for a all wheel alignment check and when the turbo starts spooling it is crazy. You can feel the tires slip on dry pavement just by gassing it, it seems like as it is coming up I am letting off to keep from hitting the limiter. What I like about it is I don't drive it enough to get used to it so it is really fun each time I take it out.
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Old 04-01-2008, 08:15 PM   #15
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Charliew:

If you are willing to invest a little money in tools, you can easily cut your own seats...
I get many of my Engine tools from Goodson...

Check out there cutters... You can get many more angles than what is listed...

They have 15,30,31,45,46,60, and 70 degree bodies listed....

Neway Seat Cutters

You can also make your own cutter inserts for them to do complex seats in one pass...

If you do a lot of cylinder head work, they will pay for themselves in no time...
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Old 04-01-2008, 10:43 PM   #16
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Quote:
Originally Posted by checque View Post
Powerband will shift to the right and you'll gain ridiculous topend. IF you do manage to push enough air thru them, those stock cams will probably offset any great gains. But if you're going to do cams later, might as well do the port work now.
With the same cams the power band should only move up not to the right or left. I just rebuilt with bigger and better heads, over-sized valves and the same cosworth cams and I gained 50ft-lb and about 40+Hp with no shift left or right. My result aren't typical because the previous heads I had where crap and the new heads allowed my motor to run more boost. IMO it would be a crime to do all that headwork though and not put cams in there. I'd pass on the whole proposition then as I think it would be better and more cost effective to just drop in cams if you're not going to do both.
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Old 04-02-2008, 01:04 PM   #17
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Sounds like the original poster is on a budget so my two cents would be the best bang for the buck with heads is in the VJ (valvejob) and valve work itself. A good 5-angel carbide cut VJ (old grinding stones need not apply) typically can be worth 20-35% of a ported heads flow.... With that said, if you are looking for improved flow, but maybe don't have the $ for portwork, then this is the place to start.

To fwillyJ, you seem to know something about heads and bring up some opinions that I think need clarification.

-I'm wondering why 25" flow numbers are provided when 28" is the industry standard?

-Are you intentionally creating an imbalance of airflow between the intake and exhaust sides? Your improvements show a pickup of ~25% on the exhaust side which is better than a lot of heads, but only 4% on the intake side... typically its good practice to keep airflow of the exhaust ports at ~75-80% of the intake ports. If you are intentionally doing this, why?

-oversized valves are always a good option unless it doesn't fit your application (interference issues). Typically a new tune will be required for a stock motor and valves only (larger than +1mm) if that gives you and indication of how well they flow

-All this talk about valves, cuts, and seats and no mention of valve backcutting? Remember that there are two low-lift instances for every valve event. One on the way open, and again on the way closed. This is why the 5-angel VJ and backcut valves will almost always yield better flow #'s but more importantly better dyno #'s.

-I'm interested to see the tests you have conducted on the exhaust seats and how you've decided that just the 45 cut is the way to go... it kinda goes against the commonly accepted theory that keeping transition angles at or less than 15 degrees (from 60 to 45 for example) to maintain proper airflow without creating turbulance and 'sheering' of the airflow...

-you mention the 75/60/45 cuts on a seat but no mention of the top cuts? (cuts in the combustion chamber above the 45) there is room for improvements in airflow here too if you are just leaving the transition from the 45 to the rest of the combustion chamber.

-why the .070 valve margin? typically on 4-valve applications that is close to the service limit of the seat... typically a .035-.055 range is what is best especially for a boosted application. Remember, that spring force on a .070 margin will hold LESS boost than a with a .045 margin. Simple physics here. I think that this would be a non-issue if you were using upgraded springs, but I figured I'd bring it up.

I am not trying to be combative, I'm just looking for clarification and some added input from you. I don't sell heads for suby's but I am VERY familiar with how they work and the mystery that is airflow.

Now on with more intellectual debate!

-Bob
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Old 04-02-2008, 05:39 PM   #18
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Everyone knowledgeable that post from their previous experiences is appreciated even if the experiences are from other motors as most improvements will apply.

But, until you port and do some angle grinds on a subie and post the flow numbers I wouldn't question anyones posted flow numbers. Unless you sink the valves there is not much room to have too many angles above the seat.

When you buy aftermarket subie valves they usually already come backcut.

It sounds like you thought he said a .070 margin I think he meant the width of the surfaces of the cuts in the seat. You kinda lost me on the .070 boost statement. I'm guessing you meant .070 edge left on the outside of the valve head past the edge of where the valve head actually seats to keep the edges of the valves thick enough to not burn up.

Without a three angle cut but a really nice blend to the seat stock usdm 04 sti heads intake will flow about 260 cfm at 28 inches with .450 lift with back cut intakes and about 210 exhaust. I think that is the norm.

I find it hard to believe you are going to get another 50 cfm (20/25%) by giving these heads a 5 angle valve job.

I'm not for sure 1mm bigger valves will give that much improvement

I'm not convinced both mods together will give 50 cfm more.

I would love to see 310 to 320 cfm on a subie head that will still make a good performer on the street.

I would love to see me proven wrong.

I don't think the original poster wanted to go full race on his heads but it's always nice to know all the options.

Can you buy these 5 angle cutters already made up for the subie valves?

Charliew

Last edited by charliew; 04-02-2008 at 06:23 PM.
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Old 04-02-2008, 07:06 PM   #19
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-I'm wondering why 25" flow numbers are provided when 28" is the industry standard? when I first started flowtesting in 1980 there was more comparative information at 10" and at 25"---virtually nothing at 28". 28"---My SF300 bench was calibrated to 25"----so that's where I started.
-As my data started adding up I ended up with many pages of hand typed flow numbers so I have been reluctant to change.
-25" to 28" or 28" to 25" is very close to a 6% difference so it's fairly simple to convert either direction.

-Are you intentionally creating an imbalance of airflow between the intake and exhaust sides? NO--I'm looking for what each particular head will give me.

-Your improvements show a pickup of ~25% on the exhaust side which is better than a lot of heads, but only 4% on the intake side... typically its good practice to keep airflow of the exhaust ports at ~75-80% of the intake ports. If you are intentionally doing this, why? I do NOT adhere to the 75-80% deal ---especially when a turbo, blower, nitrous or fuels other than common gasoline is involved.

-All this talk about valves, cuts, and seats and no mention of valve backcutting? Backcutting the valves used to help intake flow mainly below .300" lift but my porting has changed to where I just don't see any magic lately with backcuts and my porting---but I still usually do backcuts on the valves---altho I'd rather waste my time on something more productive.

Remember that there are two low-lift instances for every valve event. One on the way open, and again on the way closed. This is why the 5-angel VJ and backcut valves will almost always yield better flow #'s but more importantly better dyno #'s. I do not have any dyno experience or EFI tuning experience to judge what works.

-I am not really interested in improving low lift flow on the intake at this stage of my porting---I'd much rather be able to get over or very close to or slightly more than 270 at .400" lift--that's sort of what I'm working on.

-I feel that exhaust flow is extremely important from valve opening to when the piston is at BDC of the power stroke----but I feel that increasing low lift exhaust flow also contributes to reversion--so I like to see the big exhaust flow really start to happen at about .250" lift----but I don't flowtest at .250".

-I'm interested to see the tests you have conducted on the exhaust seats and how you've decided that just the 45 cut is the way to go... it kinda goes against the commonly accepted theory that keeping transition angles at or less than 15 degrees (from 60 to 45 for example) to maintain proper airflow without creating turbulance and 'sheering' of the airflow.
-The commonly accepted theory that you mention came from where?----people doing two valve per cylinder heads with wedge combustion chambers and with very low ports---very inefficient high swirling ports of the past.

-Heads today with multi-valves per cylinder and raised ports are much less turbulent---virtually no swirl----but much more prone to tumble.

-I am 100% against sinking the seats and creating problems with valve lash----so I have never intentionally sunk the valves to get a top angle----could be giving up some flow there----but I sort of feel like if someone gets my heads and doesn't like what I did, that I haven't totally ruined the head---so that they can go in there and work their magic.

-you mention the 75/60/45 cuts on a seat but no mention of the top cuts? (cuts in the combustion chamber above the 45) there is room for improvements in airflow here too if you are just leaving the transition from the 45 to the rest of the combustion chamber.

-why the .070 valve margin? typically on 4-valve applications that is close to the service limit of the seat... typically a .035-.055 range is what is best especially for a boosted application. I have never yet been able to make a narrow seat width work---either to increase airflow or to be able to last and still perform well over a long engine life-----quite possibly is a combination of my porting and my valve seat preparation methods.

-On stock size valves I use the old Sioux stone system because I am wanting to remove the least amount of seat depth----all I really want to do there is to get the valve seat runout and diameter respectable.

-For oversize valves I machine the seats with Goodsen/Newen style ball head drivers on a milling machine----main thing I look for here is to get the valve seat depths to less than .002" total variation from the stock height--and maintain respectable seat runout at the same time.

-It's somewhat of a challenge when using a milling machine.

Remember, that spring force on a .070 margin will hold LESS boost than a with a .045 margin. If you are meaning seat contact width of .070" vs .045" I prefer the wider number as there is a ton of heat to be dissipated off the valve into the seat ring---especially when running about 2.5 atmospheres is now so common.

-If you do the math of the actual contact patch at the valve to seat interface I feel you need to nearly 2.5 times as much heat transfer surface to keep a hot hi-powered turbo'd engine happy.

Simple physics here. I think that this would be a non-issue if you were using upgraded springs, but I figured I'd bring it up. I can't remember of any head that I've worked on for 40 years that didn't have upgraded springs.


Last edited by fwillyj; 04-03-2008 at 12:48 AM.
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Old 04-02-2008, 07:33 PM   #20
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Thank you guys,
fwillyj I am considering doing my own subie heads. I have a mill. Do you cut the other angles with the carbide cutters after you establish where the seats will end up? I guess I will check prices on Goodson/Neway stuff tomorrow.
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Old 04-02-2008, 07:46 PM   #21
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Quote:
Originally Posted by charliew View Post
Everyone knowledgeable that post from their previous experiences is appreciated even if the experiences are from other motors as most improvements will apply.

But, until you port and do some angle grinds on a subie and post the flow numbers I wouldn't question anyones posted flow numbers. Unless you sink the valves there is not much room to have too many angles above the seat.

When you buy aftermarket subie valves they usually already come backcut.

It sounds like you thought he said a .070 margin I think he meant the width of the surfaces of the cuts in the seat. You kinda lost me on the .070 boost statement. I'm guessing you meant .070 edge left on the outside of the valve head past the edge of where the valve head actually seats to keep the edges of the valves thick enough to not burn up.

Without a three angle cut but a really nice blend to the seat stock usdm 04 sti heads intake will flow about 260 cfm at 28 inches with .450 lift with back cut intakes and about 210 exhaust. I think that is the norm.

I find it hard to believe you are going to get another 50 cfm (20/25%) by giving these heads a 5 angle valve job.

I'm not for sure 1mm bigger valves will give that much improvement

I'm not convinced both mods together will give 50 cfm more.

I would love to see 310 to 320 cfm on a subie head that will still make a good performer on the street.

I would love to see me proven wrong.

I don't think the original poster wanted to go full race on his heads but it's always nice to know all the options.

Can you buy these 5 angle cutters already made up for the subie valves?

Charliew
Charlie, I appreciate the input.

For reference, a 'margin' (when talking about valves or seats) is the width of a given cut. Yes, he was referring to a .070: cut on the 45degree and I stated that something smaller would suffice without sacrificing longevity or wear.

And I was not implying that you will pickup an additional 50cfm from just the performance valvejob. If that was what you got from my long (sorry!) post, then perhaps I should revise it. All I am stating is that if he is on a budget, he can go with just the performance valvejob instead of that plus porting and in most cases pickup ~30% of the overall gains in flow from a ported and valve job'ed head. make sense? So if one were to get +25% flow from portwork and a VJ, then just the VJ should be 1/3 of that.

While I haven't ported a subie head yet, I will say that the design is more free flowing in stock form than a few other heads Ive worked on (4g63, 420A, and A855 for examples). But also know that it should not be just good flow #'s that you rely on. A good dyno should back up the flow sheet. Afterall I can get tons of flow with a crappy, hogged out port so it will flow more cfm, but it will be an absolute dog on the streets. It's all about correcting flow characteristics and improving arflow QUALITY that will make a good head.

Almost all the upgraded valves I get from Si, REV, or Ferrea are never backcut and ultimately should be done by the head shop to dial in the last thou for the best performance.

Now for whether or not you can 'fit' a 5-angle VJ on a subie seat. Yes you can. I happen to have a friend's junk head in the shop now (he's getting it cut for cross sections) for some R&D. I took a min to actually perform a 5-angle carbide cut vj on one exhaust seat. Valve margin for the 45degree is at ~.054 which is less than .070, but will have no issues of longevity or sealing. All five are the go ahead and count em'

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-Bob
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Old 04-02-2008, 08:04 PM   #22
shvrdavid
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I experimented with different angles on one of the subie heads I have and found that a double radius flows better than the multi angle...
The double radius also improved flow onset...

Doing either style valve seat will improve performance by "adding to the curve"

Dont think about cfm just at certain lift points... It is a curve that directly follows the cam profile...
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Old 04-02-2008, 08:20 PM   #23
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fwillyj I can see that you are an accomplished head porter and have done quite a few subie heads. I will say to anyone reading, that there is no replacement for the experience with any given head. My questions or thoughts are what work for me on my projects and are again not meant to discredit anyone out there.

My comment about staying to 15 degrees or less is airflow theory and may not be taught in schools like mondello's, but are still very applicable when trying to determine a good port design or valve setup. If you are not familiar with this side of things, I suggest at least a preview of airflow characteristics, thermal dynamics, and sonics.

Quote:
-The commonly accepted theory that you mention came from where?----people doing two valve per cylinder heads with wedge combustion chambers and with very low ports---very inefficient high swirling ports of the past.

-Heads today with multi-valves per cylinder and raised ports are much less turbulent---virtually no swirl----but much more prone to tumble.
I agree that swirl is bad and tumble is as well, but my point is that your exhaust profile at the seat is similar to the design of the wedge style you dislike... I would think that if you are against multi angle vj's because the seat margins end up too narrow for your liking, but realize that the multi angles provide benifits, I would recommend taking out the existing seats and upgrading. More work I know, but you would eliminate the worry of premature seat wear, but still get the benifits of the multi angle vj. Upgraded valves will last longer than stock valve just by the upgrade in materials, but if that is still a concern get them ceramic coated for added protection. something like this:


A few things to note would be to not rely 100% on flow #'s. There have been times that I have corrected port shapes and changed the margins on some of my cuts and LOST flow #'s but picked up HP. I would also backcut all valves for the reason I mentioned before. even if you don't pickup much or any cfm, it will show up on the dyno. Flow #'s are great guides, just dont get tunnel vision with the flow #'s alone.

For your reversion issues, have you ever thought to weld in or sleeve the exhaust ports so they are smaller and leave a larger lip at the header flange? That way you would have your anti reversion built in and would most likely not sacrifice much flow.... just a thought.
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Old 04-02-2008, 08:23 PM   #24
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Quote:
Originally Posted by shvrdavid View Post
I experimented with different angles on one of the subie heads I have and found that a double radius flows better than the multi angle...
The double radius also improved flow onset...

Doing either style valve seat will improve performance by "adding to the curve"

Dont think about cfm just at certain lift points... It is a curve that directly follows the cam profile...
It seems like every one you talk to has some experience with both versions and usually prefers one. The funny thing is that I know a bunch of shops that seem to get more flow from radius cuts, but the companies that I have talked to (neway for example) have actually stated they have never had an instance where they were able to gain flow over a 5 or 7 angel vj. Maybe just their way to get you to buy 5 more cutters
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Old 04-02-2008, 10:23 PM   #25
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Quote:
Originally Posted by charliew View Post
Thank you guys,
fwillyj I am considering doing my own subie heads. I have a mill. Do you cut the other angles with the carbide cutters after you establish where the seats will end up? I guess I will check prices on Goodson/Neway stuff tomorrow.
Charliew
Charliew

Check out this link... It has basic instructions, and lists some of what they offer...

Neway Seat Cutters, how to and partial parts list
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