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Fartpipe Performance Update :)
Burning Brakes
Joined: Feb 2004
Posts: 1,069
Likes: 8
From: Sanford NC
Just take your time with it bro. Mine only made 540/495rw the first time out. But I had 500+ miles on it. After I changed the oil to synthetic and changed to Pat G's cam at the prescribed time I made 555/505rw with about 1,500 on it I think. Then I worked on the tune the clutch finally came around and a more stingy dyno it made 573/530rw. It would have been 585/540+ on the dyno I used for the previous dyno's.
My point is to just give it some time and it will impress you. If you look at my dyno graph I am done at 6,000 as well but the car pulls like a raped ape till 7,000 and that is how I got my best results at the track. 6,800-7,000 shifts. The car still ran consistant 10.4's@134 shifting at 6,400 though in just about any weather. I still had the 3.42's to boot. 4.11's are going to rip to 7,000. I have full faith in Pat G's cams. The surging is hard to get rid of. I have the COS3 tune in my car with alot of work and the car still doesn't like to run below 2,000 in the first three gears. It will take alot of seat time with the lap top and experimentation to get rid of that. Get the thing to the track and see what is really up before the weather gets too warm. Good luck. If you need any thing from me just let me know.
My point is to just give it some time and it will impress you. If you look at my dyno graph I am done at 6,000 as well but the car pulls like a raped ape till 7,000 and that is how I got my best results at the track. 6,800-7,000 shifts. The car still ran consistant 10.4's@134 shifting at 6,400 though in just about any weather. I still had the 3.42's to boot. 4.11's are going to rip to 7,000. I have full faith in Pat G's cams. The surging is hard to get rid of. I have the COS3 tune in my car with alot of work and the car still doesn't like to run below 2,000 in the first three gears. It will take alot of seat time with the lap top and experimentation to get rid of that. Get the thing to the track and see what is really up before the weather gets too warm. Good luck. If you need any thing from me just let me know.
Instructor
Joined: Jul 2006
Posts: 129
Likes: 0
From: Spingfield MO
The dip.. Have your tuner add timing where the dip is and see if that helps. If not tell him to take some out there. The A/F looks a tad lean to me at the dip. It can be tuned out for the most part. The popping on decel is tune related and has nothing to do with the cam. The surging is a harder to fix than the other too because of the size of cam but with some tune time most of it can be gotten out. I have ran a cam that size in a 347 and not had surging problems.
Last edited by greatwhitess; Apr 16, 2009 at 08:20 AM.
Le Mans Master
Joined: Nov 2003
Posts: 8,308
Likes: 157
From: NJ
Just take your time with it bro. Mine only made 540/495rw the first time out. But I had 500+ miles on it. After I changed the oil to synthetic and changed to Pat G's cam at the prescribed time I made 555/505rw with about 1,500 on it I think. Then I worked on the tune the clutch finally came around and a more stingy dyno it made 573/530rw. It would have been 585/540+ on the dyno I used for the previous dyno's.
My point is to just give it some time and it will impress you. If you look at my dyno graph I am done at 6,000 as well but the car pulls like a raped ape till 7,000 and that is how I got my best results at the track. 6,800-7,000 shifts. The car still ran consistant 10.4's@134 shifting at 6,400 though in just about any weather. I still had the 3.42's to boot. 4.11's are going to rip to 7,000. I have full faith in Pat G's cams. The surging is hard to get rid of. I have the COS3 tune in my car with alot of work and the car still doesn't like to run below 2,000 in the first three gears. It will take alot of seat time with the lap top and experimentation to get rid of that. Get the thing to the track and see what is really up before the weather gets too warm. Good luck. If you need any thing from me just let me know.
My point is to just give it some time and it will impress you. If you look at my dyno graph I am done at 6,000 as well but the car pulls like a raped ape till 7,000 and that is how I got my best results at the track. 6,800-7,000 shifts. The car still ran consistant 10.4's@134 shifting at 6,400 though in just about any weather. I still had the 3.42's to boot. 4.11's are going to rip to 7,000. I have full faith in Pat G's cams. The surging is hard to get rid of. I have the COS3 tune in my car with alot of work and the car still doesn't like to run below 2,000 in the first three gears. It will take alot of seat time with the lap top and experimentation to get rid of that. Get the thing to the track and see what is really up before the weather gets too warm. Good luck. If you need any thing from me just let me know.
Thanks.
Burning Brakes
Joined: Feb 2004
Posts: 1,069
Likes: 8
From: Sanford NC
I forgot to add that I had to ditch the MAF and go full SD to make over 550rw. I know it is done all the time with FI but I am pretty sure that is the limit with a NA motor. I agree with Greatwhite to a point on your dip. It is the most drastic one I have seen. I think you can get alot of it out but I don't think you will be able to get it all out. Try every thing in that area and see what happens.
Greatwhite. Now the bucking. I would love to know what you did to get a cam this size in a 346 to not buck. I have tried every thing on my 416 with a COS 3. From 12.0 afr with 18* timing all the way up to 15.0 and 40* timing and every thing in between. It runs fine in fourth and up but 1-3 below 1,800 rpm is not fun.
Greatwhite. Now the bucking. I would love to know what you did to get a cam this size in a 346 to not buck. I have tried every thing on my 416 with a COS 3. From 12.0 afr with 18* timing all the way up to 15.0 and 40* timing and every thing in between. It runs fine in fourth and up but 1-3 below 1,800 rpm is not fun.
Drifting
Joined: Jun 2006
Posts: 1,702
Likes: 1
I forgot to add that I had to ditch the MAF and go full SD to make over 550rw. I know it is done all the time with FI but I am pretty sure that is the limit with a NA motor. I agree with Greatwhite to a point on your dip. It is the most drastic one I have seen. I think you can get alot of it out but I don't think you will be able to get it all out. Try every thing in that area and see what happens.
Greatwhite. Now the bucking. I would love to know what you did to get a cam this size in a 346 to not buck. I have tried every thing on my 416 with a COS 3. From 12.0 afr with 18* timing all the way up to 15.0 and 40* timing and every thing in between. It runs fine in fourth and up but 1-3 below 1,800 rpm is not fun.
Greatwhite. Now the bucking. I would love to know what you did to get a cam this size in a 346 to not buck. I have tried every thing on my 416 with a COS 3. From 12.0 afr with 18* timing all the way up to 15.0 and 40* timing and every thing in between. It runs fine in fourth and up but 1-3 below 1,800 rpm is not fun.
Burning Brakes
Joined: Feb 2004
Posts: 1,069
Likes: 8
From: Sanford NC
You can easily put down more the 550rw also on nitrous with a MAF.My motor doesn't buck with my cam unless it's under 1700 rpm (and that's no big deal - not severe).When comparing my cubic inches with yours...your cam isn't really any bigger than mine.The 114+4 does help to some degree though.
I don't think you can compare cam sizes and how they act cube for cube when you talk low speed and idle. Cam specs are cam specs. My cam only makes 7" of vacuum and has some where around 27* of overlap. It is also on a 112+2. It would make 7" of vacuum in just about any motor that the compression ratio is the same. The overlap and intake reverb are what kills the low speed. My 244/248 114+4 cam drove like a dream with no bucking what so ever any where. But that cam had 10" of idle vacuum and 17* of over lap. It drove the same in my 383 as it did in my 416. I must say that I am a perfectionist so even a little bucking is drastic to me. So below 1,800 in 1-3rd it would buck some. Not teeth chattering or whiplash inducing but enough to annoy me.
Instructor
Joined: Jul 2006
Posts: 129
Likes: 0
From: Spingfield MO
I did say you can make more than 550rw with FI which nitrous falls into that catagory in my book. But 550rw seems to be the threash hold for a N/A motor with a 85m MAF. Any thing that forces air into the motor isn't going to be restricted by the MAF too much. But sucking air through a straw if much harder than blowing air through a straw.
I don't think you can compare cam sizes and how they act cube for cube when you talk low speed and idle. Cam specs are cam specs. My cam only makes 7" of vacuum and has some where around 27* of overlap. It is also on a 112+2. It would make 7" of vacuum in just about any motor that the compression ratio is the same. The overlap and intake reverb are what kills the low speed. My 244/248 114+4 cam drove like a dream with no bucking what so ever any where. But that cam had 10" of idle vacuum and 17* of over lap. It drove the same in my 383 as it did in my 416. I must say that I am a perfectionist so even a little bucking is drastic to me. So below 1,800 in 1-3rd it would buck some. Not teeth chattering or whiplash inducing but enough to annoy me.
I don't think you can compare cam sizes and how they act cube for cube when you talk low speed and idle. Cam specs are cam specs. My cam only makes 7" of vacuum and has some where around 27* of overlap. It is also on a 112+2. It would make 7" of vacuum in just about any motor that the compression ratio is the same. The overlap and intake reverb are what kills the low speed. My 244/248 114+4 cam drove like a dream with no bucking what so ever any where. But that cam had 10" of idle vacuum and 17* of over lap. It drove the same in my 383 as it did in my 416. I must say that I am a perfectionist so even a little bucking is drastic to me. So below 1,800 in 1-3rd it would buck some. Not teeth chattering or whiplash inducing but enough to annoy me.
Thread Starter
Le Mans Master
Joined: Sep 2006
Posts: 9,108
Likes: 166
From: PA
Pray's trans was a stock gear ratioed M12 i believe and stock rear gear ratio aswell 3.42's. From what Kurtomac said the car literally ripped the drag radials on the street in 3rd gear like it was a street tire in the rain! Curious what we think the HP on my car would go up to if i retard the cam 2deg's to 110ICL.
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Le Mans Master
Joined: Nov 2003
Posts: 8,308
Likes: 157
From: NJ
Pray's trans was a stock gear ratioed M12 i believe and stock rear gear ratio aswell 3.42's. From what Kurtomac said the car literally ripped the drag radials on the street in 3rd gear like it was a street tire in the rain! Curious what we think the HP on my car would go up to if i retard the cam 2deg's to 110ICL.
Burning Brakes
Joined: Feb 2004
Posts: 1,069
Likes: 8
From: Sanford NC
Pray's trans was a stock gear ratioed M12 i believe and stock rear gear ratio aswell 3.42's. From what Kurtomac said the car literally ripped the drag radials on the street in 3rd gear like it was a street tire in the rain! Curious what we think the HP on my car would go up to if i retard the cam 2deg's to 110ICL.
The only correction to Kurtomac's story was that we were on 26x10 ET Street slicks that were warm. I launched at 4,000 at about 60 and the tires blew off, I shifted to 4th and spun them for a good bit more untill I started to get a little squirly. It actually surprised me as much as him. I think it was about 60* that day.
I am with Robz. Just go rape that thing and see what you got. Make adjustments as necessary.
