Best Race Header??
12-13-2011, 02:43 PM
#44
12-13-2011, 05:43 PM
#47
Nitrous it didn't help or hurt, a 12 inch extension off the collectors with my 402 ended up working out best for me (highest mph) although none of them made a huge difference in the ET.
I do know, that once I dropped the Y and LM1 off the car and went to strait extensions, or nothing at all the car picked up about .2 and almost 2 mph.
If I had a 4 inch muffler and a turndown off the bottom of the car, I'm sure it would have been better then the LM1 was but at that point I knew it was being choked, so I took the eliminate all of it approach. It worked for me.
I do know, that once I dropped the Y and LM1 off the car and went to strait extensions, or nothing at all the car picked up about .2 and almost 2 mph.
If I had a 4 inch muffler and a turndown off the bottom of the car, I'm sure it would have been better then the LM1 was but at that point I knew it was being choked, so I took the eliminate all of it approach. It worked for me.
12-13-2011, 06:42 PM
#50
That is essentially what I had on my 402 when I took it apart. I was spraying it too... I had about 12 inches of pipe, a super 44 muffler on both sides and about 12 more inches after that.
I built it to be quiet, and it was quiet enough to drive around like that. On track performance, the car would run 9.5x with it, and without it... but mph about 1 mph more without it... that could have just been the weight of the system doing that though.
In the end 1/2 this stuff.. does it translate to track performance? Maybe. Maybe not... only way to find out is to try.
I built it to be quiet, and it was quiet enough to drive around like that. On track performance, the car would run 9.5x with it, and without it... but mph about 1 mph more without it... that could have just been the weight of the system doing that though.
In the end 1/2 this stuff.. does it translate to track performance? Maybe. Maybe not... only way to find out is to try.
12-13-2011, 06:55 PM
#51
Nitrous it didn't help or hurt, a 12 inch extension off the collectors with my 402 ended up working out best for me (highest mph) although none of them made a huge difference in the ET.
I do know, that once I dropped the Y and LM1 off the car and went to strait extensions, or nothing at all the car picked up about .2 and almost 2 mph.
If I had a 4 inch muffler and a turndown off the bottom of the car, I'm sure it would have been better then the LM1 was but at that point I knew it was being choked, so I took the eliminate all of it approach. It worked for me.
I do know, that once I dropped the Y and LM1 off the car and went to strait extensions, or nothing at all the car picked up about .2 and almost 2 mph.
If I had a 4 inch muffler and a turndown off the bottom of the car, I'm sure it would have been better then the LM1 was but at that point I knew it was being choked, so I took the eliminate all of it approach. It worked for me.
I'm glad you posted this as it can be very useful to this thread on header design with almost a perfect comparison on a N/A application
You ran a production 1 3/4" header on that engine.
When I ran the same CID. as you, my 1 3/4" headers were custom built and my results were the complete opposite of yours. I ran quicker N/A WITH a y-pipe and muffler then open.
ALL headers are NOT created equal. Cool **** isn't it?
BTW. I made 3 peak RWHP open then WITH the exhaust on the dyno.
Last edited by Firehawk441; 12-13-2011 at 07:08 PM.
12-13-2011, 07:13 PM
#52
That's exactly what I was trying to get at... in the end, my production headers, with an extension, ran pretty similar to what you did with a custom header and a custom Y.
So.. which setup overall was better? Who's to say. Too may other variables that play into it in the end really... but there's certainly always more then one way to get to the same end result.
I did run a 1 3/4 header on the car when I was running it n/a, when I started spraying it, the 1 7/8 stepped to 2 inch, with the 3.5 collector, and the dual 3.5 inch setup went on the car... which ended up running pretty much the same (sans the weight change) with and without the exhaust on the car... which just told me if you go big enough on the piping so the restriction is low enough it will run pretty much like there's nothing there at all. Which, was that optimal? I don't have a clue. I do know that the car picked up .2 and 3 mph with the bigger headers then what it ran with the smaller ones.... for what that's worth.
I can say that the exhaust made it pretty quiet with the pipes on vs having them off. At least from inside the car
So.. which setup overall was better? Who's to say. Too may other variables that play into it in the end really... but there's certainly always more then one way to get to the same end result.
I did run a 1 3/4 header on the car when I was running it n/a, when I started spraying it, the 1 7/8 stepped to 2 inch, with the 3.5 collector, and the dual 3.5 inch setup went on the car... which ended up running pretty much the same (sans the weight change) with and without the exhaust on the car... which just told me if you go big enough on the piping so the restriction is low enough it will run pretty much like there's nothing there at all. Which, was that optimal? I don't have a clue. I do know that the car picked up .2 and 3 mph with the bigger headers then what it ran with the smaller ones.... for what that's worth.
I can say that the exhaust made it pretty quiet with the pipes on vs having them off. At least from inside the car
12-13-2011, 07:48 PM
#53
12-13-2011, 08:43 PM
#55
Fastest it went with the small headers, was at the nov 2007 rental I went to @ atco, and it went 9.69 @ 137 there. That was the fastest I ever got the car with the small headers.
After that, I made several changes to the car that actually added about 175 lbs to it. The front 1/2 of the cage was done, exhaust was added, full size battery was added, nose support was put in so it would stop sagging/flexing as well. Car MPH wise, the car was in the 140.5 to 141 range after the bigger headers went on it.. then a little playing with the fuel jet netted the 142.5 to 143.
I would have liked to make one more atco trip in november of 08, to really see what the changes did to the car just so I could have had similar track prep and air to when it ran the best with the smaller headers. I think that would have told more of the story. Last time I ran the car the way it was, you were in the other lane. The track that day, was an unprepped surfece for lack of a better term, I was off almost a full tenth with the 60 foot' s from what the car ran a 2 weeks earlier @ lvd.
I know the MPH improvements were 100% on, ET wise it saw a solid .18, close enough to .2 for this conversation.
Atco's prep, and air would have been nice to have one more time just to see what it would have done.
After that, I made several changes to the car that actually added about 175 lbs to it. The front 1/2 of the cage was done, exhaust was added, full size battery was added, nose support was put in so it would stop sagging/flexing as well. Car MPH wise, the car was in the 140.5 to 141 range after the bigger headers went on it.. then a little playing with the fuel jet netted the 142.5 to 143.
I would have liked to make one more atco trip in november of 08, to really see what the changes did to the car just so I could have had similar track prep and air to when it ran the best with the smaller headers. I think that would have told more of the story. Last time I ran the car the way it was, you were in the other lane. The track that day, was an unprepped surfece for lack of a better term, I was off almost a full tenth with the 60 foot' s from what the car ran a 2 weeks earlier @ lvd.
I know the MPH improvements were 100% on, ET wise it saw a solid .18, close enough to .2 for this conversation.
Atco's prep, and air would have been nice to have one more time just to see what it would have done.
12-13-2011, 09:19 PM
#58
12-13-2011, 10:14 PM
#60
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Firehawk441 I got on QTP's website to look at his muffler and I didn't see it on there. Tell me if I'm just plain dumb and missing it or if it isn't on there.