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1 3/4 vs 1 7/8

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Old 03-02-2009, 08:51 PM
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Default 1 3/4 vs 1 7/8

I believe I know the answer to this question but wanted a little feedback. The mods are in the signature. I think the exhaust is a little weak and want to help it out some. Looking into a set of long tubes but am just unsure whether I should step up to the bigger 1 7/8. Will I be leaving any numbers on the table? I know its a long discussion about mids vs lts but I think they are holding it back a little. Thanks
Old 03-02-2009, 08:52 PM
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nope, you're fine. 1 3/4 is enough

Last edited by Ericbigmac83; 03-02-2009 at 08:58 PM.
Old 03-02-2009, 08:54 PM
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I would definately get LT's. But with your mods the 1 7/8 would be a waste of money IMO
Old 03-02-2009, 09:01 PM
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1 3/4" will net you a little power, but 1 7/8" probably wont matter on your setup. But if you are planning on a bigger setup later, then the 1 7/8" will be the way to go so you don't have to worry about it later. 1 7/8" are best I think on bigger motors (400ci+). They have been proven to make power on L92 heads but I think that is due to how well the heads flow though. Unless you aren't planning on something along those lines I would stick with a 1 3/4" longtube That is my .02
Old 03-02-2009, 09:03 PM
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Here's some reading materal...https://ls1tech.com/forums/generatio...o-results.html
Old 03-02-2009, 09:04 PM
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I would go with the 1 7/8 headers. You probly wouldn't gain much if any over the smaller headers but you will have room to grow later if you plan to go more radical.
Old 03-02-2009, 09:05 PM
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I had followed that untill it got a little clustered....
Old 03-02-2009, 09:11 PM
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I would go 1 7/8 if I could do it again. I think you could gain alittle more on your H/C engine then they got with a stock engine. If you you ever went with a fast intake that would realy open up your H/C and get more potential out of the 1 7/8 lt's. Just my $.02
Old 03-03-2009, 07:47 AM
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Slowhawk just put some 1 7/8 headers on his red rocket shop car and has dyno sheet. He picked up some good power for a stock motor. Low end did not suffer.
https://ls1tech.com/forums/eastern-m...-new-mods.html
Old 03-03-2009, 01:07 PM
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From Slowhawk. "The headers are 1 7/8 with a 3" into 3.5" Y-pipe"

Anyone know what the previous set up was?
Old 03-03-2009, 02:56 PM
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here is my take when I switched (kinda long)
car is a H/C/I A4 it put down 434 rwp with a TCI 3500 stall and 3:23 gears

1. added 3:73 and dynoed at 424..so lost ten rwhp with gear swap

2. added a 5c converter witch is a 42-4400 stall..How much did I lose by going with a bigger stall I dont know cuz at the same time I swapped out my hedman 1 5/8 step to 1 3/4 headers for hooker 1 7/8..Now I put down 426rwhp

3.so did I lose 10rwhp from the bigger stall and the headers gave me 12rwhp back or did I not lose any by going bigger with the stall and the headers only gave me 2 rwhp..I would imagine that by going with a BIGGER stall I would lose some rwhp on the dyno how much is hard to say as it looks like the headers gave some back..

4. I did this cuz the old ones were bad and since I plan on going bigger or spray why not
hope this helps
Old 03-03-2009, 05:16 PM
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I had mac mid tubes and dyno tuned it (check out the sig) and i just ordered my today and they should be here friday and after talking to the guys at texas-speed i agree i should pick up some power w/o losing anything
Old 03-03-2009, 09:07 PM
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Originally Posted by 1989GTA
From Slowhawk. "The headers are 1 7/8 with a 3" into 3.5" Y-pipe"

Anyone know what the previous set up was?
It appears it didnt have headers on it before?
Old 03-04-2009, 08:41 AM
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Originally Posted by 1989GTA
From Slowhawk. "The headers are 1 7/8 with a 3" into 3.5" Y-pipe"

Anyone know what the previous set up was?

It was bone stock.
Old 03-04-2009, 08:50 AM
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I'm running Edelbrock Victor 1 7/8 long tubes, 3 1/2 collectors, true duals with a crossover and side exit. The crossover helps, but I still lost some low end torque. It isn't noticable except when I need it coming out of corners or a rolling start race. Having a 6 speed car helps with that too. The 1 7/8 tubes will make difference when I install the FI 427 though.
That said, I agree with the rest of the guys who are saying plan ahead for your upgrades. Because, in my case, the 1 7/8 didn't hurt enough now to offset thier usefulness later.




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