1 3/4'' or 1 7/8'' headers?
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Im almost finished assembling all of my parts to put my ls1 in my s13 240sx, and im curious as to pros and cons of these header options...My enigine set up is a 99 LS1 bored 10 over, ARP everything, 853 heads that have been worked, TSP MS3 112 cam, LS6 intake, 42# injectors, and BBK 80mm TB. I am shooting for mid 400whp and I have the two header options from Sikky, just wondering if you guys think the increased primary size would be beneficial or not neccesary.
Thanks,
Phil
Thanks,
Phil
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Agreed, especially with the aggressive heads/cam combo you're running, get the bigger headers!
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Hell yea! Whats done to yours? I havent seen another one in person besides a drift car at NOPI, love to ride in one, besides mine which ive been waitin over 2 yrs to get done...
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Just wanted to jump into the conversation. When I bough my headers a few years ago (arh 1 3/4) I didn't do much research and just went with the smaller ones. I am now looking to do a head and cam package. Would this be a problem or will i have to go with 1 7/8?
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^^^ you will be fine... But BIGGER is BETTER in this case... One of the guys from TSP wrote a thread about the test they had between the two headers and they had a gain goin from 1 3/4 to 1 7/8... I can't find it right now but I'm sure one of the guys from TSP can fill in the rest... You probably squeeze out mid 400hp with that setup... PRC 2.5 LS6 heads would be ideal for that MS3... My opinion.
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^^^ you will be fine... But BIGGER is BETTER in this case... One of the guys from TSP wrote a thread about the test they had between the two headers and they had a gain goin from 1 3/4 to 1 7/8... I can't find it right now but I'm sure one of the guys from TSP can fill in the rest... You probably squeeze out mid 400hp with that setup... PRC 2.5 LS6 heads would be ideal for that MS3... My opinion.
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Now, if you are going to be using nitrous or forced induction, this is a different case. Those setups feed off free flowing exhaust and there is power to be gained with 1 7/8. HOWEVER, if you already have a set of 1 3/4 primaries on your setup, it isn't worth spending the money and time taking them off and putting on 1 7/8''. Gains would be fairly minimal. Again, this goes for your forced induction setups. Here is a thread to support this claim. Keep in mind when you read this thread, the guy swapped his 1 3/4 for 1 7/8 and made a little gain down low but he has a forced induction setup. Even then, the gains were pretty minimal.http://www.smokinvette.com/corvettef...ad.php?t=27830
Again OP, do your research on this. In my opinion, you should go with a set of 1 3/4'' on your setup. Going with 1 7/8'' will do nothing for you and probably hinder performance to an extent. I do have personal experience in this so feel free to PM with questions...In the end, we are all just holding the tail on this dog...youre the one screwing it.
Last edited by TransAmcoupe98; 06-13-2012 at 06:20 AM.
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So for my own peice of mind and to protect the money I have already sunk into my car fund:
My new Darton Sleeved 427 with a:
Comp 256/264 - 625/625 - 113+4
Dart 250-68 2.08/1.60 head
Harland Sharp rockers
ported FAST 90
Holley 90TB
Flow matched 42lb Ford green tops
Dragonslayer 4" stroke crank
Diamond Dome pistons
all being squeezed and forced into my freshly JET HOT coated 1 3/4 Kooks LT's is not going to work well? I should sell them and get 1 7/8 or stepped headers?
Or will the 1 3/4 be sufficient?
I plan on running dual 2 1/2 oval tubing over the axle and into a single muffler and out as 2 1/2 duals with slash cut tips at the rear of the car.
Anyone see a problem with this set up? If so then why? I may need to do some more saving before dropping this set up in the car.
Chad
My new Darton Sleeved 427 with a:
Comp 256/264 - 625/625 - 113+4
Dart 250-68 2.08/1.60 head
Harland Sharp rockers
ported FAST 90
Holley 90TB
Flow matched 42lb Ford green tops
Dragonslayer 4" stroke crank
Diamond Dome pistons
all being squeezed and forced into my freshly JET HOT coated 1 3/4 Kooks LT's is not going to work well? I should sell them and get 1 7/8 or stepped headers?
Or will the 1 3/4 be sufficient?
I plan on running dual 2 1/2 oval tubing over the axle and into a single muffler and out as 2 1/2 duals with slash cut tips at the rear of the car.
Anyone see a problem with this set up? If so then why? I may need to do some more saving before dropping this set up in the car.
Chad
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I don't think it will matter a whole lot but if you haven't gotten them get the 1 7/8, I use the 1 3/4, didn't think I was going to put a whole lot of parts on it, but I still made almost 500rwhp
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