1 3/4 vs 1 7/8 headers and ORY what's deciding factor in correct size.
05-29-2013, 10:10 PM
#23
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Pay attention to the Y merge. There are some really
crappy ones out there. Any made by sticking one tube
into the other, is liable to suck (my Jet-Hots were
terrible, the stuck-in tube protruded half an inch into
the other and you could see that the angle looked
inclined to produce reversion; older version TSP Y
was nearly as bad for stick-in; I spent hours with a
flex shaft tool stuck down a shop-vac tube, grinding
back the sharps on both).
Two tubes that meet parallel and then go to a
reducer, are much better for interleaving the pulses.
crappy ones out there. Any made by sticking one tube
into the other, is liable to suck (my Jet-Hots were
terrible, the stuck-in tube protruded half an inch into
the other and you could see that the angle looked
inclined to produce reversion; older version TSP Y
was nearly as bad for stick-in; I spent hours with a
flex shaft tool stuck down a shop-vac tube, grinding
back the sharps on both).
Two tubes that meet parallel and then go to a
reducer, are much better for interleaving the pulses.
05-29-2013, 10:51 PM
#25
Ive seen one car gain 0 hp and lose torque then I saw another one gain both power and torque going from 1 3/4 headers to 1 7/8. Once my pacesetters rust out I am going to get my own results and post them on here.
05-29-2013, 10:51 PM
#26
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even a stock ls1 will gain with 1-7/8 over 1-3/4. The larger primaries outperform the smaller ones period. They los no torque down low compared to the 1-3/4 and make more power up op so its a no brainer if you're buying new headers.
Also leaving stock manifolds on that car would be a major choking point, I'd estimate on the field of losing 25whp or more by not doing a good set of lt's.
Also leaving stock manifolds on that car would be a major choking point, I'd estimate on the field of losing 25whp or more by not doing a good set of lt's.
05-30-2013, 02:06 AM
#27
Heads make a difference as I pointed out in my earlier post. Valve size is just part of it. Some heads have very weak exhaust ports and need a crutch. Other times, the cam is all wrong and has too much exhaust duration for an efficient head or not enough for an inefficient head. The headers then can only do what they can do.
05-30-2013, 10:55 AM
#28
Heads make a difference as I pointed out in my earlier post. Valve size is just part of it. Some heads have very weak exhaust ports and need a crutch. Other times, the cam is all wrong and has too much exhaust duration for an efficient head or not enough for an inefficient head. The headers then can only do what they can do.
09-03-2024, 12:36 AM
#29
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1 3/4 vs 1 7/8 I am building a iron LS2 6.0 for my 02 T/A Flat tops, 243 heads and GM ASA cam. Car has a borla adjustable catback on it already. I am really leaning toward going with TSP headers because of how affordable they are. Not looking to drop 1500 on headers and a Y
It will be a daily driver on nice day's and will never go to the track and not real concerned with total HP output. I just want a nice strong running good sounding reliable street DD motor and it does have a stick. With that said
1. What are the tried and proven reasons for going with one size over the other or is there a point at which x amount of mods and cubic inches and cams necessitate the 1 3/4 vs 1 7/8 header choice.
2. How much of a average loss in output if I were to just run OE manifolds and punched out cats on the above.
Keep in mind this combo is for a daily driver w average speed of 0-75 and mostly highway driving and a few WOT back road runs every blue moon or so.
It will be a daily driver on nice day's and will never go to the track and not real concerned with total HP output. I just want a nice strong running good sounding reliable street DD motor and it does have a stick. With that said
1. What are the tried and proven reasons for going with one size over the other or is there a point at which x amount of mods and cubic inches and cams necessitate the 1 3/4 vs 1 7/8 header choice.
2. How much of a average loss in output if I were to just run OE manifolds and punched out cats on the above.
Keep in mind this combo is for a daily driver w average speed of 0-75 and mostly highway driving and a few WOT back road runs every blue moon or so.
