Experience after race porting heads
07-29-2018, 07:13 PM
#1
Instructor
Thread Starter
Experience after race porting heads
Hey guys
I just want to get your feedback and experience of those that have gotten a raceport job when they redid their heads. I recently had my heads redone from ahp and they did a great job, the heads look awesome. I got the stage 4 package with btr duel springs w titanium retainers pm guides and the race porting with minimum milling. The car is a 09 z06 stock with a bb axle back exhaust.
Im curious how your cars drive. In very low rmps the car feels very lazy, not snappy and quick when you hit the throttle. I have an 07 z06 completely stock and it seems stronger and much snappier with quicker throttle response. I drove them back to back so I could tell the difference and compare.
I am eventually planning on installing a mild/medium duty cam like the ahp 116 or something a little more aggressive. I didn't want to sacrifice all the low end torque to get a little more power up top.
I was planning on driving it a while and then doing the cam and getting a tune.
From your guys experience is this lethargic performance expected and due to the race porting or after a tune will it be more like it was before? By getting the above mentioned cam will I still have the same driving feel with a little more power all around?
Thanks for your thoughts.
I just want to get your feedback and experience of those that have gotten a raceport job when they redid their heads. I recently had my heads redone from ahp and they did a great job, the heads look awesome. I got the stage 4 package with btr duel springs w titanium retainers pm guides and the race porting with minimum milling. The car is a 09 z06 stock with a bb axle back exhaust.
Im curious how your cars drive. In very low rmps the car feels very lazy, not snappy and quick when you hit the throttle. I have an 07 z06 completely stock and it seems stronger and much snappier with quicker throttle response. I drove them back to back so I could tell the difference and compare.
I am eventually planning on installing a mild/medium duty cam like the ahp 116 or something a little more aggressive. I didn't want to sacrifice all the low end torque to get a little more power up top.
I was planning on driving it a while and then doing the cam and getting a tune.
From your guys experience is this lethargic performance expected and due to the race porting or after a tune will it be more like it was before? By getting the above mentioned cam will I still have the same driving feel with a little more power all around?
Thanks for your thoughts.
07-29-2018, 07:30 PM
#2
Racer
Hey guys
I just want to get your feedback and experience of those that have gotten a raceport job when they redid their heads. I recently had my heads redone from ahp and they did a great job, the heads look awesome. I got the stage 4 package with btr duel springs w titanium retainers pm guides and the race porting with minimum milling. The car is a 09 z06 stock with a bb axle back exhaust.
Im curious how your cars drive. In very low rmps the car feels very lazy, not snappy and quick when you hit the throttle. I have an 07 z06 completely stock and it seems stronger and much snappier with quicker throttle response. I drove them back to back so I could tell the difference and compare.
I am eventually planning on installing a mild/medium duty cam like the ahp 116 or something a little more aggressive. I didn't want to sacrifice all the low end torque to get a little more power up top.
I was planning on driving it a while and then doing the cam and getting a tune.
From your guys experience is this lethargic performance expected and due to the race porting or after a tune will it be more like it was before? By getting the above mentioned cam will I still have the same driving feel with a little more power all around?
Thanks for your thoughts.
I just want to get your feedback and experience of those that have gotten a raceport job when they redid their heads. I recently had my heads redone from ahp and they did a great job, the heads look awesome. I got the stage 4 package with btr duel springs w titanium retainers pm guides and the race porting with minimum milling. The car is a 09 z06 stock with a bb axle back exhaust.
Im curious how your cars drive. In very low rmps the car feels very lazy, not snappy and quick when you hit the throttle. I have an 07 z06 completely stock and it seems stronger and much snappier with quicker throttle response. I drove them back to back so I could tell the difference and compare.
I am eventually planning on installing a mild/medium duty cam like the ahp 116 or something a little more aggressive. I didn't want to sacrifice all the low end torque to get a little more power up top.
I was planning on driving it a while and then doing the cam and getting a tune.
From your guys experience is this lethargic performance expected and due to the race porting or after a tune will it be more like it was before? By getting the above mentioned cam will I still have the same driving feel with a little more power all around?
Thanks for your thoughts.
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Millenium Z06 (07-30-2018)
07-29-2018, 07:52 PM
#4
Instructor
Thread Starter
My end goal is around 550-600 whp and reliability is a high priority for me. I did the port work, springs, now so I wouldn't have to take the heads off again when I did the cam. I would also add intake and headers for the whole package.
Should the car really feel less torquey than it was before. Would a tune restore some of that? I know race porting extends the length of the runners to increase flow up top.
Should the car really feel less torquey than it was before. Would a tune restore some of that? I know race porting extends the length of the runners to increase flow up top.
07-29-2018, 08:02 PM
#5
Hey guys
I just want to get your feedback and experience of those that have gotten a raceport job when they redid their heads. I recently had my heads redone from ahp and they did a great job, the heads look awesome. I got the stage 4 package with btr duel springs w titanium retainers pm guides and the race porting with minimum milling. The car is a 09 z06 stock with a bb axle back exhaust.
Im curious how your cars drive. In very low rmps the car feels very lazy, not snappy and quick when you hit the throttle. I have an 07 z06 completely stock and it seems stronger and much snappier with quicker throttle response. I drove them back to back so I could tell the difference and compare.
I am eventually planning on installing a mild/medium duty cam like the ahp 116 or something a little more aggressive. I didn't want to sacrifice all the low end torque to get a little more power up top.
I was planning on driving it a while and then doing the cam and getting a tune.
From your guys experience is this lethargic performance expected and due to the race porting or after a tune will it be more like it was before? By getting the above mentioned cam will I still have the same driving feel with a little more power all around?
Thanks for your thoughts.
I just want to get your feedback and experience of those that have gotten a raceport job when they redid their heads. I recently had my heads redone from ahp and they did a great job, the heads look awesome. I got the stage 4 package with btr duel springs w titanium retainers pm guides and the race porting with minimum milling. The car is a 09 z06 stock with a bb axle back exhaust.
Im curious how your cars drive. In very low rmps the car feels very lazy, not snappy and quick when you hit the throttle. I have an 07 z06 completely stock and it seems stronger and much snappier with quicker throttle response. I drove them back to back so I could tell the difference and compare.
I am eventually planning on installing a mild/medium duty cam like the ahp 116 or something a little more aggressive. I didn't want to sacrifice all the low end torque to get a little more power up top.
I was planning on driving it a while and then doing the cam and getting a tune.
From your guys experience is this lethargic performance expected and due to the race porting or after a tune will it be more like it was before? By getting the above mentioned cam will I still have the same driving feel with a little more power all around?
Thanks for your thoughts.
07-30-2018, 02:10 AM
#6
Melting Slicks
I would not choose AHP as a vendor with the goals you mentioned. Guides, yes. For horsepower, there are better options, WCCH, AI, LME, BES. My two cents. If you are still in the market for a cam I would definitely advise that you shop around.
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Millenium Z06 (07-30-2018)
07-30-2018, 08:34 AM
#7
Hey guys
I just want to get your feedback and experience of those that have gotten a raceport job when they redid their heads. I recently had my heads redone from ahp and they did a great job, the heads look awesome. I got the stage 4 package with btr duel springs w titanium retainers pm guides and the race porting with minimum milling. The car is a 09 z06 stock with a bb axle back exhaust.
Im curious how your cars drive. In very low rmps the car feels very lazy, not snappy and quick when you hit the throttle. I have an 07 z06 completely stock and it seems stronger and much snappier with quicker throttle response. I drove them back to back so I could tell the difference and compare.
I am eventually planning on installing a mild/medium duty cam like the ahp 116 or something a little more aggressive. I didn't want to sacrifice all the low end torque to get a little more power up top.
I was planning on driving it a while and then doing the cam and getting a tune.
From your guys experience is this lethargic performance expected and due to the race porting or after a tune will it be more like it was before? By getting the above mentioned cam will I still have the same driving feel with a little more power all around?
Thanks for your thoughts.
I just want to get your feedback and experience of those that have gotten a raceport job when they redid their heads. I recently had my heads redone from ahp and they did a great job, the heads look awesome. I got the stage 4 package with btr duel springs w titanium retainers pm guides and the race porting with minimum milling. The car is a 09 z06 stock with a bb axle back exhaust.
Im curious how your cars drive. In very low rmps the car feels very lazy, not snappy and quick when you hit the throttle. I have an 07 z06 completely stock and it seems stronger and much snappier with quicker throttle response. I drove them back to back so I could tell the difference and compare.
I am eventually planning on installing a mild/medium duty cam like the ahp 116 or something a little more aggressive. I didn't want to sacrifice all the low end torque to get a little more power up top.
I was planning on driving it a while and then doing the cam and getting a tune.
From your guys experience is this lethargic performance expected and due to the race porting or after a tune will it be more like it was before? By getting the above mentioned cam will I still have the same driving feel with a little more power all around?
Thanks for your thoughts.
Last edited by 73DBG; 07-30-2018 at 12:15 PM. Reason: Sp
07-30-2018, 08:49 AM
#8
Team Owner
Was the car tuned after? Data logs? Could be pinging from milling and pulling timing. The car should not slow down with heads. All these threads about cars not making good power, and the concept that they just need more and more parts thrown at them is getting ridiculous. A good set of heads should pick up power everywhere, even on a stock car with no other mods.
07-30-2018, 09:29 AM
#9
When someone says "race port", that to me is all in. Intake swirl damn completely removed, runners enlarged, throats opened up, bowl shaping and blending...... When all that is done, airspeed is reduced at lower rpm, and idle/off idle characteristics suffer from it. Emissions are also a concern and it's unlikely to pass a sniff test with even the stock camshaft. And contrary to general belief, flow bench numbers will not look all that fantastic either. A porting job like this will not be for a street car. Total valve lift will be a minimum of 0.700".
So when you say "race port", what does that really mean?
Regardless of all that, you need to have the air models recalibrated after you change anything in the engine that will affect air flow. The speed density model is especially important, as it's predictive. SD is also what helps make throttle response more snappy.
So when you say "race port", what does that really mean?
Regardless of all that, you need to have the air models recalibrated after you change anything in the engine that will affect air flow. The speed density model is especially important, as it's predictive. SD is also what helps make throttle response more snappy.
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07-30-2018, 11:36 AM
#10
Racer
I'm not sure you can really pounce the vendor just yet with only minimal details on the build, tune, and data for that particular car. There could be a LOT of things going on.
07-30-2018, 11:43 AM
#11
Team Owner
Your comment suggests that power is more important than reliability. Anyone can make huge power if they disregard concern for reliability. Great advice!
I'm not sure you can really pounce the vendor just yet with only minimal details on the build, tune, and data for that particular car. There could be a LOT of things going on.
I'm not sure you can really pounce the vendor just yet with only minimal details on the build, tune, and data for that particular car. There could be a LOT of things going on.
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jayyyw (07-30-2018)
07-30-2018, 02:01 PM
#13
Melting Slicks
Your comment suggests that power is more important than reliability. Anyone can make huge power if they disregard concern for reliability. Great advice!
I'm not sure you can really pounce the vendor just yet with only minimal details on the build, tune, and data for that particular car. There could be a LOT of things going on.
I'm not sure you can really pounce the vendor just yet with only minimal details on the build, tune, and data for that particular car. There could be a LOT of things going on.
07-30-2018, 04:39 PM
#14
Supporting Vendor
Member Since: Sep 2013
Location: Harbor City California
Posts: 2,817
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When someone says "race port", that to me is all in. Intake swirl damn completely removed, runners enlarged, throats opened up, bowl shaping and blending...... When all that is done, airspeed is reduced at lower rpm, and idle/off idle characteristics suffer from it. Emissions are also a concern and it's unlikely to pass a sniff test with even the stock camshaft. And contrary to general belief, flow bench numbers will not look all that fantastic either. A porting job like this will not be for a street car. Total valve lift will be a minimum of 0.700".
So when you say "race port", what does that really mean?
Regardless of all that, you need to have the air models recalibrated after you change anything in the engine that will affect air flow. The speed density model is especially important, as it's predictive. SD is also what helps make throttle response more snappy.
So when you say "race port", what does that really mean?
Regardless of all that, you need to have the air models recalibrated after you change anything in the engine that will affect air flow. The speed density model is especially important, as it's predictive. SD is also what helps make throttle response more snappy.
Race ported heads have much larger runners than our street ported heads thus the intake air charge on the race ported heads has a much lower velocity. This translates to slowet or slugish feeling down low.
Race pirted heads are designed for the rpm range a race car spends most its time (4500,5k rpms on up).
Our street ported heads are desiged for street/strip/light track use with stock to mild cam and rpms where most street cars spend their life (1500-6500 rpms).
If anyone has any questions or needs any further details on any of yhe above feel free to give us a call 310-326-2399 or shoot us an email hp@americanheritageperformance.com
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rpmextra (07-30-2018)
07-30-2018, 05:07 PM
#15
Hey guys
I just want to get your feedback and experience of those that have gotten a raceport job when they redid their heads. I recently had my heads redone from ahp and they did a great job, the heads look awesome. I got the stage 4 package with btr duel springs w titanium retainers pm guides and the race porting with minimum milling. The car is a 09 z06 stock with a bb axle back exhaust.
Im curious how your cars drive. In very low rmps the car feels very lazy, not snappy and quick when you hit the throttle. I have an 07 z06 completely stock and it seems stronger and much snappier with quicker throttle response. I drove them back to back so I could tell the difference and compare.
I am eventually planning on installing a mild/medium duty cam like the ahp 116 or something a little more aggressive. I didn't want to sacrifice all the low end torque to get a little more power up top.
I was planning on driving it a while and then doing the cam and getting a tune.
From your guys experience is this lethargic performance expected and due to the race porting or after a tune will it be more like it was before? By getting the above mentioned cam will I still have the same driving feel with a little more power all around?
Thanks for your thoughts.
I just want to get your feedback and experience of those that have gotten a raceport job when they redid their heads. I recently had my heads redone from ahp and they did a great job, the heads look awesome. I got the stage 4 package with btr duel springs w titanium retainers pm guides and the race porting with minimum milling. The car is a 09 z06 stock with a bb axle back exhaust.
Im curious how your cars drive. In very low rmps the car feels very lazy, not snappy and quick when you hit the throttle. I have an 07 z06 completely stock and it seems stronger and much snappier with quicker throttle response. I drove them back to back so I could tell the difference and compare.
I am eventually planning on installing a mild/medium duty cam like the ahp 116 or something a little more aggressive. I didn't want to sacrifice all the low end torque to get a little more power up top.
I was planning on driving it a while and then doing the cam and getting a tune.
From your guys experience is this lethargic performance expected and due to the race porting or after a tune will it be more like it was before? By getting the above mentioned cam will I still have the same driving feel with a little more power all around?
Thanks for your thoughts.
Without a cam, intake possibly more cubes and gears, race porting makes the ports larger which slows the port speed which kills torque
07-30-2018, 05:11 PM
#16
My end goal is around 550-600 whp and reliability is a high priority for me. I did the port work, springs, now so I wouldn't have to take the heads off again when I did the cam. I would also add intake and headers for the whole package.
Should the car really feel less torquey than it was before. Would a tune restore some of that? I know race porting extends the length of the runners to increase flow up top.
Should the car really feel less torquey than it was before. Would a tune restore some of that? I know race porting extends the length of the runners to increase flow up top.
Race porting enlarges the runners, not lengthen them, a true race port would be a high rpm benefit but a low rpm detriment. Port velocity = torque/power. Unnecessarily larger ports create a lazy head and slow port velocity which hurts torque and creates the condition you now have.
07-30-2018, 05:16 PM
#17
I'm not sure you can really pounce the vendor just yet with only minimal details on the build, tune, and data for that particular car. There could be a LOT of things going on.
I'm not sure you can really pounce the vendor just yet with only minimal details on the build, tune, and data for that particular car. There could be a LOT of things going on.
07-30-2018, 05:39 PM
#18
I’m a bit confused on why you chose a race port OP? Did you call or email with anyone at AHP? If so did you discuss current and future modifications and plans for the cars intended use? If “yes” is the answer for any of those questions above, and someone from AHP advised you to go with “race porting” on a daily driver or weekend toy with just the most basic of bolt ons and zero intention of doing the modifications race ported heads would benefit from, as well as zero intentions of tracking the car in the near future.....I think most would agree you should be a little upset about that for sure.
Now if the anwser to the few questions above is “no” than there’s really nothing anyone could have done about that, builders and tuners can only advise with the information provided by the customer, I’ve ran into the fact that my lack of knowledge or ability to articulate what specifically I’m wanting lead to my expectations being different from what I assumed was going to happen or be done. Specifics matter in these situations...... if you just bring a bunch of part to a shop and say “install this stuff for me” or just start “adding to cart” and clicking options without fully understanding what all that will do and how it will effect your desired outcome ***** not gonna turn out well.
Now if the anwser to the few questions above is “no” than there’s really nothing anyone could have done about that, builders and tuners can only advise with the information provided by the customer, I’ve ran into the fact that my lack of knowledge or ability to articulate what specifically I’m wanting lead to my expectations being different from what I assumed was going to happen or be done. Specifics matter in these situations...... if you just bring a bunch of part to a shop and say “install this stuff for me” or just start “adding to cart” and clicking options without fully understanding what all that will do and how it will effect your desired outcome ***** not gonna turn out well.
07-30-2018, 05:50 PM
#19
Gonna take a lot of cam to make those race ports work and if that wasn't your goal, you'll probably be looking for a new set of heads
07-30-2018, 08:58 PM
#20
Le Mans Master
Hit the nail on the head.
Race ported heads have much larger runners than our street ported heads thus the intake air charge on the race ported heads has a much lower velocity. This translates to slowet or slugish feeling down low.
Race pirted heads are designed for the rpm range a race car spends most its time (4500,5k rpms on up).
Our street ported heads are desiged for street/strip/light track use with stock to mild cam and rpms where most street cars spend their life (1500-6500 rpms).
If anyone has any questions or needs any further details on any of yhe above feel free to give us a call 310-326-2399 or shoot us an email hp@americanheritageperformance.com
Race ported heads have much larger runners than our street ported heads thus the intake air charge on the race ported heads has a much lower velocity. This translates to slowet or slugish feeling down low.
Race pirted heads are designed for the rpm range a race car spends most its time (4500,5k rpms on up).
Our street ported heads are desiged for street/strip/light track use with stock to mild cam and rpms where most street cars spend their life (1500-6500 rpms).
If anyone has any questions or needs any further details on any of yhe above feel free to give us a call 310-326-2399 or shoot us an email hp@americanheritageperformance.com
Before you modify, please understand your goals and mod to those goals. ALL mods require some compromise!
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Z.06 (07-30-2018)