LT4 exhaust restriction questions>
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From: Bartlett Illinois
LT4 exhaust restriction questions>
On a typical Stock LT4 cat-back or LT1 for that matter.. which pieces are the most restrictive.
I would tend to think it is the mufflers but what about the resonator?
I would tend to think it is the mufflers but what about the resonator?
Melting Slicks
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From: Drive it Like You Hate it Cincinnati OH
Re: LT4 exhaust restriction questions> (-=Jeff=-)
I'm wondering the same thing. I've thougt of going with eliminators, but i may just remove the resonator and replace it with straight pipe or a x-pipe.
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From: Bartlett Illinois
Re: LT4 exhaust restriction questions> (tntcorvette)
Yeah I have seen the shootouts but I am still wondering if the stock 2.75" LT1/4 Cat-back is actually 2.75" through out the whole system. I heard that the resonator internal tube DIA is around 2" if this is the case.. I shoudl switch back to my Flowmaster Cat-Back then
[Modified by -=Jeff=-, 8:11 AM 7/17/2002]
[Modified by -=Jeff=-, 8:11 AM 7/17/2002]
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From: Probably in the paint booth....
Re: LT4 exhaust restriction questions> (-=Jeff=-)
[QUOTE] I heard that the resonator internal tube DIA is around 2" if this is the case.. [QUOTE]
It's seems it was bigger than that when I took pics of it. Did you allready install the one I sent ya ? I did send it to you didn't I ?
I see if I can find the pics & post them.
Neal
It's seems it was bigger than that when I took pics of it. Did you allready install the one I sent ya ? I did send it to you didn't I ?
I see if I can find the pics & post them.
Neal
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From: Bartlett Illinois
Re: LT4 exhaust restriction questions> (Arisa)
I heard that the resonator internal tube DIA is around 2" if this is the case..
It's seems it was bigger than that when I took pics of it. Did you allready install the one I sent ya ? I did send it to you didn't I ?
I see if I can find the pics & post them.
Neal
It's seems it was bigger than that when I took pics of it. Did you allready install the one I sent ya ? I did send it to you didn't I ?
I see if I can find the pics & post them.
Neal
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From: Bartlett Illinois
Re: LT4 exhaust restriction questions> (-=Jeff=-)
Okay.. I opened my box with the resonator from Neal.. it is 3" straight through. Guess the mufflers are the restriction
EDIT.. I meant 2.75" not 3"
[Modified by -=Jeff=-, 7:15 AM 7/18/2002]
EDIT.. I meant 2.75" not 3"
[Modified by -=Jeff=-, 7:15 AM 7/18/2002]
Le Mans Master
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Re: LT4 exhaust restriction questions> (tntcorvette)
there is an exhaust shootout in corvette fever awhile ago with a g/s and I believe the dynomax system just replaced the mufflers and picked up ~8 or so rwhp.
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Re: LT4 exhaust restriction questions> (Lone Ranger)
Take a close look at the tips where they come out of the muffler(if you still have the stock tips) they are only about 2".
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Melting Slicks
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From: NW Chicago Suburbs
Re: LT4 exhaust restriction questions> (-=Jeff=-)
I have my old stock LT4 exhaust system in my garage. The system is 2.75" OD except the inlets/outlets to the resonator necks down to 2.5" and the inlets to the mufflers neck down to 2.3". My Corsa is 2.75" OD all the way.
Eric
Eric
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From: Bartlett Illinois
Re: LT4 exhaust restriction questions> (silver & red CE)
I have my old stock LT4 exhaust system in my garage. The system is 2.75" OD except the inlets/outlets to the resonator necks down to 2.5" and the inlets to the mufflers neck down to 2.3". My Corsa is 2.75" OD all the way.
Eric
Eric
But as far as I know.. Corsa is 2.5" just like the Flowmaster and I know that the stock tube are bigger in some areas compared to the flowmaster system I have in the garage.
I am also not arguing the idea that an aftermarket exhaust does not flow better, I just would like to see how well the stock exhaust can flow by just changing a few pieces..
Melting Slicks
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From: NW Chicago Suburbs
Re: LT4 exhaust restriction questions> (-=Jeff=-)
...But as far as I know.. Corsa is 2.5" just like the Flowmaster and I know that the stock tube are bigger in some areas compared to the flowmaster system I have in the garage....
Eric
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From: Bartlett Illinois
Re: LT4 exhaust restriction questions> (silver & red CE)
I don't know anything about the Flowmaster system, but I can assure the Corsa is 2.75" OD (outside diameter) all the way. When speaking of exhaust most people refer to the ID (inside diameter) which for the Corsa is 2.5" all the way.
Eric
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Re: LT4 exhaust restriction questions> (tntcorvette)
when I get home tomorrow i'll summarize the ariticle for everyone to see. Its pretty informative and will open some eyes to cat back systems.
Melting Slicks
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From: NW Chicago Suburbs
Re: LT4 exhaust restriction questions> (-=Jeff=-)
So just so I understand correctly.. if you by Exhaust clamps for the Corsa do you get 2.5 or 2.75?
Eric
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From: Bartlett Illinois
Re: LT4 exhaust restriction questions> (silver & red CE)
So just so I understand correctly.. if you by Exhaust clamps for the Corsa do you get 2.5 or 2.75?
I don't know because the Corsa system comes with really nice clamps from the factory, hence I haven't purchased any. But when I pull out my venier calipers and measure the Corsa, all the pipes are 2.75" OD. All the joints are flared so the minimum OD throughout the catback is 2.75". The OD of the flared joints is 3.0". Hope this helps.
Eric
I don't know because the Corsa system comes with really nice clamps from the factory, hence I haven't purchased any. But when I pull out my venier calipers and measure the Corsa, all the pipes are 2.75" OD. All the joints are flared so the minimum OD throughout the catback is 2.75". The OD of the flared joints is 3.0". Hope this helps.
Eric
I know that TNT is going to post the exhaust info from Corvette fever.. but I would like other input as well
Melting Slicks
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From: NW Chicago Suburbs
Re: LT4 exhaust restriction questions> (-=Jeff=-)
...yeah it does THANKS.. Last question.. did you notice or have any info that shows you got a gain from stock to the Corsa?
Eric
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From: Bartlett Illinois
Re: LT4 exhaust restriction questions> (tntcorvette)
OK gang, here we go. Its in the June 1998 issue of Corvette Fever, page 19 - 23 and the testing was done by Jim Van Dorn of automasters in california @ K&N's dyno facility.
A stock 1996 Grand Sport put out 299/307 in hp.torque.
Here are the results in horsepower/torque
B&B Triflow 310/310
Dynomax 304/310
Borla 304/310
Flowmaster 306/309
Powereffects closed position 299/308 & open position 311/313
Also the cost of these systems is something to look at when comparing the power to cost ratio. The list prices are based on the print date of the article.
B&B $1275
Dynomax $229 (mufflers system only)
Borla $1795
Flowmaster $837
Power Effects $1599
Some other intresting test results include de @ idle & warm and then crusing @ 70mph in 6th gear:
B&B 82/94
Dynomax 86/96
Borla 92/100
Flowmaster 92/97
PowerEffects 90 (open) 92 (closed)/ 100 (closed)/103 (open)
Oh yeah, why is the magazine you are looking for always at the opposite end of the pile?
Enjoy all!!!
A stock 1996 Grand Sport put out 299/307 in hp.torque.
Here are the results in horsepower/torque
B&B Triflow 310/310
Dynomax 304/310
Borla 304/310
Flowmaster 306/309
Powereffects closed position 299/308 & open position 311/313
Also the cost of these systems is something to look at when comparing the power to cost ratio. The list prices are based on the print date of the article.
B&B $1275
Dynomax $229 (mufflers system only)
Borla $1795
Flowmaster $837
Power Effects $1599
Some other intresting test results include de @ idle & warm and then crusing @ 70mph in 6th gear:
B&B 82/94
Dynomax 86/96
Borla 92/100
Flowmaster 92/97
PowerEffects 90 (open) 92 (closed)/ 100 (closed)/103 (open)
Oh yeah, why is the magazine you are looking for always at the opposite end of the pile?
Enjoy all!!!
I have that at home too, This is why I cannot see spending between $700-$1200 for an exhaust system for those kind of gains. Granted that on a modded motor there will be more gains, but still. I found a set of mufflers I may try with my catback I have now.. We will see
Le Mans Master
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Re: LT4 exhaust restriction questions> (tntcorvette)
OK gang, here we go. Its in the June 1998 issue of Corvette Fever, page 19 - 23 and the testing was done by Jim Van Dorn of automasters in california @ K&N's dyno facility.
A stock 1996 Grand Sport put out 299/307 in hp.torque.
Here are the results in horsepower/torque
<snipped>
A stock 1996 Grand Sport put out 299/307 in hp.torque.
Here are the results in horsepower/torque
<snipped>
Pro
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From: Houston Tx
Re: LT4 exhaust restriction questions> (tntcorvette)
tntcorvette.....excellent info.....much appreciated.
Pretty much confirmed what I had suspected. B&B makes excellent power, is large enough (3") to accomodate more power later , aint cheap - but not the most either, is loud but no THAT loud.
I still have yet to hear one from in the car to see how badly it resonates , but coming from a Cobra with shorties, off road H pipe (no cats), and Flowmaster catback , I somehow dont think it will sound that loud.
Bang for the buck with Magnaflow is great but I want a complete high quality system, not just the mufflers. I also think the B&B's look the best IMHO. I do , however like the fact the the PE's are adjustable and they sound AWESOME, they are just too expensive and heavy.
From what I have read about Corsa's , which were not in that test, they generally seem to yeild 7-12 rwhp which puts them right there as well(although who knows what they would yeild on the same day same dyno , side by side with the others). They are relatively cheap listing around $995, and they are relatively quiet and do not resonate. The only down side to me is the 2.5" tubing may be a bit restrictive for an engine putting down over 400 rwhp (which is where I am going with this car). :seeya
Pretty much confirmed what I had suspected. B&B makes excellent power, is large enough (3") to accomodate more power later , aint cheap - but not the most either, is loud but no THAT loud.
I still have yet to hear one from in the car to see how badly it resonates , but coming from a Cobra with shorties, off road H pipe (no cats), and Flowmaster catback , I somehow dont think it will sound that loud.
Bang for the buck with Magnaflow is great but I want a complete high quality system, not just the mufflers. I also think the B&B's look the best IMHO. I do , however like the fact the the PE's are adjustable and they sound AWESOME, they are just too expensive and heavy.
From what I have read about Corsa's , which were not in that test, they generally seem to yeild 7-12 rwhp which puts them right there as well(although who knows what they would yeild on the same day same dyno , side by side with the others). They are relatively cheap listing around $995, and they are relatively quiet and do not resonate. The only down side to me is the 2.5" tubing may be a bit restrictive for an engine putting down over 400 rwhp (which is where I am going with this car). :seeya
Racer
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From: Cave Creek AZ
Re: LT4 exhaust restriction questions> (Shriker)
Eckler's lists the B&Bs for $1229. I found a place on the WEB that sold them for $100 less. Eckler's states that they will meet any price lower than theirs. So I told them I found the B&Bs at a cheaper price. They matched it. Funny thing is that they didn't even ask me where I found the lower price. Could I have said I found them even cheaper? Don't know what their pain threshold might be. Just a hint if you decide to go through Eckler's.
:)
:)
