Is upgrading from shorties to Long tubes worth the $$ ?
#31
Originally posted by badblackta
As far as the price thing goes, bbk ceramic coated shorties from jegs are 479.99 and I paid 525.00 for my jet hot long tubes. Not that much diffference in the price, and you will get more power from the long tubes. In my opinion it is definitely worth going with the long tubes. Just a thought. And to the guy who was saying that the cars needed to be the same to show realistic performance gains, I have another friend who has an a4 93 z28 which is stock except for jet hots and duals, who runs a 13.87 to the 14.2 of the other 93 z that has shorties. Say what you want, Long tubes are better.
As far as the price thing goes, bbk ceramic coated shorties from jegs are 479.99 and I paid 525.00 for my jet hot long tubes. Not that much diffference in the price, and you will get more power from the long tubes. In my opinion it is definitely worth going with the long tubes. Just a thought. And to the guy who was saying that the cars needed to be the same to show realistic performance gains, I have another friend who has an a4 93 z28 which is stock except for jet hots and duals, who runs a 13.87 to the 14.2 of the other 93 z that has shorties. Say what you want, Long tubes are better.
Frank
#32
Well I didnt read your post but I am just saying that I get more power from my car because I put them on and now the car will not hook up at all. I do not have to have a dyno to tell that the car is running alot better. I believe that the long tubes are worth the money. Not saying that shorties dont make power over stock manifolds but the guy that started the post has ported heads and a cam which would cause me to think that he could use the long tubes, so the motor could breath a bit better. And I will tell you how fast I go with Lt's on saturday because that is when the track opens
#33
I also did not fall into the longtube hype. Fred/Baxter, Frank, Frank, Joe, Vizard, and price hehe, all influenced me before i got my SLP midlengths (it was a tossup with the macs but i knew the motor wouldn't be staying stock).
To me it seams that most headers fall into 5 catagories.
1 5/8 shorties
1 3/4 shorties
1 5/8 mid
1 3/4 mid
1 3/4 longtube
Shorties,
i wouldn't bother with unless its a dual cat car in california.
Mids,
1 5/8 for stock heads(Mac's for plug access and price!)
1 3/4 for ported heads(as&m, slp 94/95)
Longtubes,
1 3/4 for ported heads and a heavy car in need of low end.
(FLPs, TPIS, Jethot, Hooker - and don't forget to get a ypipe!)
http://www.geocities.com/MotorCity/T...92/vizard4.jpg
In this artivle Vizard publish's a chart that suggests 1 5/8" primaries for stock lt1 head flow, and 1 3/4 for the majority of ported heads like lyods (sp) and such. In the same article he also debunks a myth that equal length primaries are important citing that the volume of the all the primaries+ the collector(secondaries) is what is important.
http://www.sandersonheaders.com/letsgettech3.htm
That article also makes some interesting points. Its test was performed on a bigblock, but the same concepts apply. Think about this, if your car is not a max effort drag car would you rather select a header slightly too large or too small? I agree with the article that you should err on the small side because the difference at low mid rpms AND part throttle where you will be the majority of the time on the street, the scavenging will be much more effective with the smaller header.
Enough rambling,
I guess in the case of 93 formy here who does have head work and a cam, maybe he would benefit from 1 3/4" primaries. I still am not sure the gains would be worth all the headach and bloody knuckles of a header swap.
just my opinion,
Brent
To me it seams that most headers fall into 5 catagories.
1 5/8 shorties
1 3/4 shorties
1 5/8 mid
1 3/4 mid
1 3/4 longtube
Shorties,
i wouldn't bother with unless its a dual cat car in california.
Mids,
1 5/8 for stock heads(Mac's for plug access and price!)
1 3/4 for ported heads(as&m, slp 94/95)
Longtubes,
1 3/4 for ported heads and a heavy car in need of low end.
(FLPs, TPIS, Jethot, Hooker - and don't forget to get a ypipe!)
http://www.geocities.com/MotorCity/T...92/vizard4.jpg
In this artivle Vizard publish's a chart that suggests 1 5/8" primaries for stock lt1 head flow, and 1 3/4 for the majority of ported heads like lyods (sp) and such. In the same article he also debunks a myth that equal length primaries are important citing that the volume of the all the primaries+ the collector(secondaries) is what is important.
http://www.sandersonheaders.com/letsgettech3.htm
That article also makes some interesting points. Its test was performed on a bigblock, but the same concepts apply. Think about this, if your car is not a max effort drag car would you rather select a header slightly too large or too small? I agree with the article that you should err on the small side because the difference at low mid rpms AND part throttle where you will be the majority of the time on the street, the scavenging will be much more effective with the smaller header.
Enough rambling,
I guess in the case of 93 formy here who does have head work and a cam, maybe he would benefit from 1 3/4" primaries. I still am not sure the gains would be worth all the headach and bloody knuckles of a header swap.
just my opinion,
Brent
#34
I've seen stock LT1's pick up nothing from LT's
I've also seen Stock LT1's run LT's and run much better.
I would think if you have stock heads and a smaller cam that shortys would be fine. The bigger the cam and better heads long tubes would be better.
I've had the Edelbrocks for about 4 years and they have performed well on my car. Never a leak, easy to install and a good gain. My car ran 11's with stock heads and the hot cam with a 100 shot
I've also seen Stock LT1's run LT's and run much better.
I would think if you have stock heads and a smaller cam that shortys would be fine. The bigger the cam and better heads long tubes would be better.
I've had the Edelbrocks for about 4 years and they have performed well on my car. Never a leak, easy to install and a good gain. My car ran 11's with stock heads and the hot cam with a 100 shot
#35
Oh yeah, i forgot to include a quote from when i got my car dyno'd. It put down 343 SAE rwhp/tq. There where some mustang guys and others checking it out after the pull, impressed by decent numbers from a small cam and untouched heads.
An impressed individual with their head under the hood said, "those longtube headers are probably helping out a lot!"
"....actually those are SLP midlengths," i got a chuckle out of that.
-brent
An impressed individual with their head under the hood said, "those longtube headers are probably helping out a lot!"
"....actually those are SLP midlengths," i got a chuckle out of that.
-brent
#36
FWIW, I ran 9.3-9.4 consistantly in the 1/8 (CAI and cat-back)before the FLP LTs. Right after that, I ran 8.6-8.7 consistantly. I know I couldn't have been a better driver in such a short amont of time. Maybe it was the new plugs and wires.
#37
A very common misconception is that shorties will give better low end response than LTs, this is wrong. Primary length is important when it comes to the timing of the exhaust pulse. Long tubes will produce lower peaks than midlengths which are both going to produce a lower peak than true shorties. However to take advantage of a true shorty header, you would need to spin your motor far beyond the range that 99% (or more) of LT1s will ever see. There is a primary length calculator on this here site, and if you don't believe me go play around with it a little.
I went with LTs because of the better low end, as my car has yet to get on a track. Anyway, JMHO
Chris
I went with LTs because of the better low end, as my car has yet to get on a track. Anyway, JMHO
Chris
#38
wow... lots of mis-information and "anecdotal evidence" in this string.
Facts are that high rpms torque/hp can be tuned for using:
- short primaries w/wider diameters
Low rpm torque/hp can be tuned for by using:
- long primaries w/narrow diameters
That's the facts. Obviously several ways to suppliment the LT1 are possible.
a) All longtube headers I'm aware of use a larger 1 3/4" primary to ensure high rpm breathing, and the length suppliments the low rpms.
b) Shorties obviously come in both versions, although most see better PEAK numbers with the larger primary size, as would be expected since our hp peaks at fair high rpms. The interesting thing to note would be the greater numbers the 1 5/8" primary headers can put down at low rpms. With the short tube length though your sort pitting the two against eachother.
finally c) mid-length headers in either version. If you plan on running at higher rpms, you'll want the larger primary. If you plan on keeping it about stock, its close to a toss up. If these are for an L98 with a low red-line... 1 5/8" are your ticket.
looking at these accepted truthes of header design, it's clear that an LT1 kept under 7000 rpms or so will see best results with a 1 3/4", mid-length or shortie primary. How short is too short, is really determined by your rpm limit. How wide a primary is too wide is probably limited by your displacement and how often the engine is driven at low rpms.
I'd wager AS&M headers would similar, if not better numbers than a LT design in a modified LT1, while the LT's on a L98 style engine would shine more.
The only consideration besides exhaust theory... is packaging.
A) do the headers fit in the vehicle/application?
B) is the fit smooth enough that you don't have to make any extreme angles or flow inhibitions?
This is where LT headers probably outshine the shorties to a fair extent. AS&M arn't too bad in comparison, but like LT's... I've heard their a real PITA to install. Parts A) and B) tend to be a compromise in this regard. If it uses up ALL the available space, and tries to minimize flow distrubances, it most likely will be a PITA to slide into the car.
Personal preference really for a stock application, 5 or 10 poines at low rpms vs. high rpms won't make much difference for a daily driver. For race applications though, you probably want to look at shorter and wider primary tubes.
This is just want I've read in Popular Hot Rodding and Drag Racer magazine (each has done a series on exhaust and header design) so take it for what its worth.
Facts are that high rpms torque/hp can be tuned for using:
- short primaries w/wider diameters
Low rpm torque/hp can be tuned for by using:
- long primaries w/narrow diameters
That's the facts. Obviously several ways to suppliment the LT1 are possible.
a) All longtube headers I'm aware of use a larger 1 3/4" primary to ensure high rpm breathing, and the length suppliments the low rpms.
b) Shorties obviously come in both versions, although most see better PEAK numbers with the larger primary size, as would be expected since our hp peaks at fair high rpms. The interesting thing to note would be the greater numbers the 1 5/8" primary headers can put down at low rpms. With the short tube length though your sort pitting the two against eachother.
finally c) mid-length headers in either version. If you plan on running at higher rpms, you'll want the larger primary. If you plan on keeping it about stock, its close to a toss up. If these are for an L98 with a low red-line... 1 5/8" are your ticket.
looking at these accepted truthes of header design, it's clear that an LT1 kept under 7000 rpms or so will see best results with a 1 3/4", mid-length or shortie primary. How short is too short, is really determined by your rpm limit. How wide a primary is too wide is probably limited by your displacement and how often the engine is driven at low rpms.
I'd wager AS&M headers would similar, if not better numbers than a LT design in a modified LT1, while the LT's on a L98 style engine would shine more.
The only consideration besides exhaust theory... is packaging.
A) do the headers fit in the vehicle/application?
B) is the fit smooth enough that you don't have to make any extreme angles or flow inhibitions?
This is where LT headers probably outshine the shorties to a fair extent. AS&M arn't too bad in comparison, but like LT's... I've heard their a real PITA to install. Parts A) and B) tend to be a compromise in this regard. If it uses up ALL the available space, and tries to minimize flow distrubances, it most likely will be a PITA to slide into the car.
Personal preference really for a stock application, 5 or 10 poines at low rpms vs. high rpms won't make much difference for a daily driver. For race applications though, you probably want to look at shorter and wider primary tubes.
This is just want I've read in Popular Hot Rodding and Drag Racer magazine (each has done a series on exhaust and header design) so take it for what its worth.
#39
YOu guys are gonna make me buy a set of Edelbrock headers and put them on my car to prove the point that shorties and LTs have no benefits. I would probably say the shorties will produce better returns.
Anyone want to donate a set of shorties and some dyno money? I can make 3 pulls one day, then 3 pulls the next day. Just let me know who is interested and I can provide you accounts for deposits and a shipping address.
Car in question: 94 Z28 TH350/Vig3500 LT4 heads with larger valves and bowl work. 52mm TB, LT1 edit, K&N CAI, LTCC, LT/Duals, 3.73s. Pulled 340RWHP (rich), runs the 1/8th in 7.8-7.6 at 89-91MPH.
Just let me know when you want this to go down....
Anyone want to donate a set of shorties and some dyno money? I can make 3 pulls one day, then 3 pulls the next day. Just let me know who is interested and I can provide you accounts for deposits and a shipping address.
Car in question: 94 Z28 TH350/Vig3500 LT4 heads with larger valves and bowl work. 52mm TB, LT1 edit, K&N CAI, LTCC, LT/Duals, 3.73s. Pulled 340RWHP (rich), runs the 1/8th in 7.8-7.6 at 89-91MPH.
Just let me know when you want this to go down....
#41
I have heard a few of the shortie guys state that long tubes are good for low which is where you need your power because to have a good et it helps to have a good 60 foot time. If you cant get out of the hole your et will be crap. But someone will probably have a time or something that they will post that will probably have the use of nitrous to make up for their low end problem.
#42
I figure I have a typical street car that just happens to run very well for a HOT cam...so who wants the test?
I will say this, I had my car on the rollers with stock PE Tables, 3.23s, 17" AREs, stock LT4 H/I, HOT cam, stock WP, BBK Shorties, A4/Yank ST3500 and pulled 320ish. Went back with the bowl work, CSI EWP, LTs/duals, 15" Draglites, TH350/3600 stall and only pulled 340ish after adjusting the AFR.
I would have thought the bowl work, EWP, LTs/duals would have netted more than 20 tuned HP. The first pull was the same HP as before with not all that stuff done. I picked up the HP from the limited amount of tuning I did and it was still a tad rich. SO, I do not feel that I picked up much of anything with all that work....all of it seems to be tuning....
I will say this, I had my car on the rollers with stock PE Tables, 3.23s, 17" AREs, stock LT4 H/I, HOT cam, stock WP, BBK Shorties, A4/Yank ST3500 and pulled 320ish. Went back with the bowl work, CSI EWP, LTs/duals, 15" Draglites, TH350/3600 stall and only pulled 340ish after adjusting the AFR.
I would have thought the bowl work, EWP, LTs/duals would have netted more than 20 tuned HP. The first pull was the same HP as before with not all that stuff done. I picked up the HP from the limited amount of tuning I did and it was still a tad rich. SO, I do not feel that I picked up much of anything with all that work....all of it seems to be tuning....
#43
94formulabz, 12SCNDZ and Steve in Seattle:
Excellent responses guys. Thanks for basing things on facts, and not speculation.
I kept hearing LT's, LT's, LT's... If you want power, go LT's. The more I looked into it however, and the more I looked at times and traps that guys were seeing with mids, I started to doubt the whole LT thing. Sure LT's are great, but so are mids/shorties, and your posts help to make that more understandable.
It all depends on the application. I'm staying with stock heads, so my 1 5/8" MAC mids should be just what I'm looking for. Can't wait to get them on in the spring.
Again, excellent numbers from that CC502 Brent. That's what I'm looking at for next year. Either that or the CC305, but I'm leaning towards the CC502.
Thanks,
Dan
Excellent responses guys. Thanks for basing things on facts, and not speculation.
I kept hearing LT's, LT's, LT's... If you want power, go LT's. The more I looked into it however, and the more I looked at times and traps that guys were seeing with mids, I started to doubt the whole LT thing. Sure LT's are great, but so are mids/shorties, and your posts help to make that more understandable.
It all depends on the application. I'm staying with stock heads, so my 1 5/8" MAC mids should be just what I'm looking for. Can't wait to get them on in the spring.
Again, excellent numbers from that CC502 Brent. That's what I'm looking at for next year. Either that or the CC305, but I'm leaning towards the CC502.
Thanks,
Dan
Last edited by stereomandan; 01-20-2004 at 05:45 PM.
#44
Originally posted by badblackta
I have heard a few of the shortie guys state that long tubes are good for low which is where you need your power because to have a good et it helps to have a good 60 foot time. If you cant get out of the hole your et will be crap. But someone will probably have a time or something that they will post that will probably have the use of nitrous to make up for their low end problem.
I have heard a few of the shortie guys state that long tubes are good for low which is where you need your power because to have a good et it helps to have a good 60 foot time. If you cant get out of the hole your et will be crap. But someone will probably have a time or something that they will post that will probably have the use of nitrous to make up for their low end problem.
Frank