Who to have Port Your head???
#111
Who to have Port Your head???
I would agree that Drag racers are a different breed, and that they are looking for the last pony possible. I would however disagree with the thought that some how porting could lead to less reliability. I ABSOLUTELY think that you can do more harm than good if you don't know what you are doing, but a good porting job should not effect reliability in the least. Just my opinion of course, but unless the port job is so radical that you are blurring the lines of structural integrity, I don't see where you will have a problem. that is of course if you know what you are doing.
A particular motor will only produce power efficiently if it's heads design is efficient and effective. The motor is only as good as it's ability to push/pull air through it.
Don't get me wrong Yjacket, I fully understand and appreciate your post. Just have a different idea on reliability.
Most reliability issues that I've had (actually ever had) in racing had nothing to do with the head. We've broke cams, cranks, rods, pistons etc. etc. I've never broke a head. Correction, We've cracked heads and ripped rocker perches out, but that had nothing to do with porting. Had more to do with the 1471 sittin' on top of the motor.
A particular motor will only produce power efficiently if it's heads design is efficient and effective. The motor is only as good as it's ability to push/pull air through it.
Don't get me wrong Yjacket, I fully understand and appreciate your post. Just have a different idea on reliability.
Most reliability issues that I've had (actually ever had) in racing had nothing to do with the head. We've broke cams, cranks, rods, pistons etc. etc. I've never broke a head. Correction, We've cracked heads and ripped rocker perches out, but that had nothing to do with porting. Had more to do with the 1471 sittin' on top of the motor.
#114
#115
Who to have Port Your head???
Originally posted by: thebigshow
222, i do have a question. is it possible to re-port? i know if its to small u can go bigger, but is there a way to patch up and re-port? i knew some of the drag-bike builders in the IHRA did this for test purposes, but i didnt know if it could be done for a person who had it ported two years ago and with the new R&D would like to upgrade?[img]i/expressions/face-icon-small-wink.gif[/img]
222, i do have a question. is it possible to re-port? i know if its to small u can go bigger, but is there a way to patch up and re-port? i knew some of the drag-bike builders in the IHRA did this for test purposes, but i didnt know if it could be done for a person who had it ported two years ago and with the new R&D would like to upgrade?[img]i/expressions/face-icon-small-wink.gif[/img]
No problem- on the best CNC digitized porting, the ports are partially filled in before going to the CNC and then reconfigured.
222
#118
Who to have Port Your head???
Questions (not for you Allred!!):
1. why would some porters see no difference between 1mm oversize valves and the biggest valve you can stuff in the head, while others see massive gains??
2. Is there any danger installing 1 size over valves on the stock seats?
3. why would we put the same size valves in a big bore head as a stock bore head?
222
1. why would some porters see no difference between 1mm oversize valves and the biggest valve you can stuff in the head, while others see massive gains??
2. Is there any danger installing 1 size over valves on the stock seats?
3. why would we put the same size valves in a big bore head as a stock bore head?
222
#119
Who to have Port Your head???
Originally posted by: DSNUT
I have been thinking about this a bit but haven't had time to research it so, like Ben362, I reserve the right to change my mind.[img]i/expressions/face-icon-small-wink.gif[/img]
If you upgrade your valves to 40/34 valves but don't increasethe lift or duration of your stock cams, you could probably have gained as much valve flow capacity by leaving stock valves and going nuts with lift and duration. Ron
I have been thinking about this a bit but haven't had time to research it so, like Ben362, I reserve the right to change my mind.[img]i/expressions/face-icon-small-wink.gif[/img]
If you upgrade your valves to 40/34 valves but don't increasethe lift or duration of your stock cams, you could probably have gained as much valve flow capacity by leaving stock valves and going nuts with lift and duration. Ron
I believe the second half of the above statement depends on that.....
222