3 inch dp vs. 2.5 inch dp
#1
3 inch dp vs. 2.5 inch dp
I have the opportunity to purchase a 2.5 inch Racing Beat downpipe for $80.
My question is: Will this make it much harder to reach my goal of 300whp than a 3inch DP if I run a 3 inch cat back after this 2.5 inch DP, will that affect performance at all?
My question is: Will this make it much harder to reach my goal of 300whp than a 3inch DP if I run a 3 inch cat back after this 2.5 inch DP, will that affect performance at all?
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Bollocks. A 2.5" DP will have a very noticable effect on performance compared to stock. I know, I've just fitted one. For mild mods a 2.5" DP is fine, but a 3" one will always be better. That's just logical.
However if you're aiming for 300rwhp then you're going to have to change the entire turbo anyway, so even if you buy or make a 3" DP for the stock turbo you'll need to get another one made for the new turbo.
Since you can get the 2.5" one cheap now, I'd just get it. It means less money wasted on your way to buying a new 300rwhp turbo/manifold/wastegate/DP combo.
However if you're aiming for 300rwhp then you're going to have to change the entire turbo anyway, so even if you buy or make a 3" DP for the stock turbo you'll need to get another one made for the new turbo.
Since you can get the 2.5" one cheap now, I'd just get it. It means less money wasted on your way to buying a new 300rwhp turbo/manifold/wastegate/DP combo.
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#5
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I didn't find much of a difference with my DP. There was some, just not a lot. Don't know your other mods, but how much of a boost increase did you get?
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For $80, why not? For that price, go ahead and get it. Then find yourself a bada$$ old school Nissan/Datsun tuner to build you the rest of your exhaust.
300rwhp used to be my goal too. But that was way overshot with this BNR Stage 2 turbo.
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Turbonut: Do you have a 3" catback as well? I have the Bonez combo, and it was a huge difference for me compared to stock. But, if you still have stock catback, then the difference i probably not that big....
I had MazdaSpeed 3" catback with stockcats for a year, little difference but not much, but together with the Bonez turboflo = fells like 40 bhp! Not to mention spoolup....
I had MazdaSpeed 3" catback with stockcats for a year, little difference but not much, but together with the Bonez turboflo = fells like 40 bhp! Not to mention spoolup....
#9
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Originally posted by Snrub
I didn't find much of a difference with my DP. There was some, just not a lot.
I didn't find much of a difference with my DP. There was some, just not a lot.
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Don't know your other mods, but how much of a boost increase did you get?
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Last edited by NZConvertible; 05-26-03 at 06:37 AM.
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