1 3/4 Or 1 7/8 primary??
Thread Starter
Pro
Joined: Oct 2007
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From: EL Paso Texas
1 3/4 Or 1 7/8 primary??
getting headers soon. either kooks or dynatech. why the two primary sizes? i will not do any head or cam work ever. might SC in 2-3 years. ii think i should go with 1 3/8 ? only mods is a halltech stinger and future mail order tune with headers insatll.
ed 2002 z06
ed 2002 z06
Last edited by stock z06; Nov 26, 2007 at 06:41 PM.
Le Mans Master
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From: Bradenton FLORIDA
Original Founding Member!
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From: Granby, MA
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Melting Slicks
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From: Los Angeles
I have no doubt the low end would suffer... but how much? If I have FI plans in the future as well, but would like to do LT's now... obviously I would want the primaries designed for FI.So how much would the low end suffer... comparable to putting 20" rears where your stock 18s" were (for example?). Would there be similar gain in high end on the other end of the RPM band?
Just curious to see if the N/A application of 1 7/8ths inch primaries (while planning for FI) is not worth it. Would it really be better to do FI on the stock exhaust manifolds and just do the larger primary headers later and retune?
Le Mans Master
Joined: Aug 2001
Posts: 8,145
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From: Bradenton FLORIDA
I have no doubt the low end would suffer... but how much? If I have FI plans in the future as well, but would like to do LT's now... obviously I would want the primaries designed for FI.So how much would the low end suffer... comparable to putting 20" rears where your stock 18s" were (for example?). Would there be similar gain in high end on the other end of the RPM band?
Just curious to see if the N/A application of 1 7/8ths inch primaries (while planning for FI) is not worth it. Would it really be better to do FI on the stock exhaust manifolds and just do the larger primary headers later and retune?
Hmmm, if you are sure you are going to FI, it would make sense to do them now.....and it is not a HUGE diff, just not the ideal.
Former Vendor
Joined: Nov 2005
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From: Spring Texas
St. Jude Donor '08
For stock discplacement N/A setups, the smaller size will give you faster exhaust velocity and better torque without inhibiting flow. The larger primary will have slower velocity (not good)
The only reason I'd go with the 1 7/8" primaries is if you went FI or bored/stroked your engine.
The only reason I'd go with the 1 7/8" primaries is if you went FI or bored/stroked your engine.
