all longtubes created equal?

urban96

bubb rubb says:"woo woooooo"
Founding Member
Sep 24, 2002
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Syracuse, NY
if i got a set of BBK long tubes would i have to go with a BBK mid pipe?

or could i use pretty much any mid pipe?

i would like tu run a prochamber with the BBK's... would it work?
 
it all depends on what connector type/style they use. for example:

SLP LT's use a slip fit design and are only compatible with their x-pipe, or others with slip-fit design (none that i'm aware of).

of course you'll need a shorty mid-pipe, which the PC is available in. im pretty sure ive seen someones sig around here that had BBK LT's and Mac PC, but i could be mistaken. what type does BBK use? Ball and socket flange?
 
helty said:
it all depends on what connector type/style they use. for example:

SLP LT's use a slip fit design and are only compatible with their x-pipe, or others with slip-fit design (none that i'm aware of).
Does that mean that their X-Pipe is only compatible with their LT's? I am eventually going to get the SLP X-Pipe but I'm also going to get Mac LT's. Are they compatible?
 
nic01scgt said:
Does that mean that their X-Pipe is only compatible with their LT's? I am eventually going to get the SLP X-Pipe but I'm also going to get Mac LT's. Are they compatible?
no. unless you weld them together (and possibly ruin the headers/mid-pipe for future uses)
 
In order to run the Prochamber with the BBK's you would have to modify it a little bit. I remember reading a post about a guy who did just that. He had to widen the Prochamber on each end a little to matte it up with the BBK's. He pretty much did it with a hammer, so it can be done. I had MAC LT's with a Prochamber before, and then swapped to BBK LT's. I did not want to risk a leak and just went with a BBK mid pipe.
 
If I remember correctly... My bf had BBK LT's with the prochamber midpipe for like a week while he waited for the bbk midpipe he ordered to come in. i don't think they had problems with it fitting...
i'm sure the shop can make it fit ;) (if you're not doing it yourself that is)
 
the question was "are all longtubes equal. "

no.

diameter and length determined sonic pulse arrival at the exhaust port. tuned to a particular rpm. small diameter tubes allow shorter tubes for a set rpm. larger diameter forces longer tubes for lower rpm's, but if they are the same length as a amaller tube dia. they operate at higher rpm's. you see 1 1/2",1 5/8", and 1 3/4" as common diameters for 4.6. if the tubes are the same length the 1 3/4" will make more high rpm torque(hp). they sacrifice low rpm pulse efficiencies for top end. 1 1/2" good for very low, 1 3/4" good for very high. 1 5/8" good for compromise mid range. the only real "best" long tube is stepped racing headers.


every change in diameter the an exhaust pulse make sends a sonic pulse down the exhaust and back to the port. if the pulse arrives at the time the exhaust valve opens, it scavenges. one particular rpm is when each sonic low pressure pulse arrives, so it misses or has less efficiency at any other rpm. stepped tubes send a variety of pulses that arrive when the last steps pulse starts to lose efficiency. thereby scavenging at all rpms starting at about 2500.

the collector: the diameter and length of the collector determines efficiency at producing a very low pressure. the best collectors are merge collectors. they have special cones between the tubes where most collectors have a dead square spot. a good collector can produce a low enough pressure area to allow running a tube to the block to depressurize the block. believe it or not you can gain as much as 30hp from real vacuum in block(long tubes not so much. it requires an electric pump. two tubes to the valve covers and oil seperators to keep them clean.


headers 101.
 
as long as your willing to do some costom work, any mid pipe can fited to any long tube.
But by doing that, your chancing leak for one, and like someone said, your possibly ruin pipes for the future.

I would love to get PC for my BBK, but for the reason of chancing leak, i don't want to attempt it
 
^ wow, man you must live on google huh? Thats alot of info, and how can i do this vaccume thing? I assume that it what the racers do by pulling the vac on the crank case? PM me if you want, and tell about any problems that may occur with it...such as if the pump were to fail or if it would effect oiling....im all about freeing up HP (parisitic loss recovery patrol here :D) Thanks man.
 
not google.


experience.

we did it back in the VW days. 1985.


all of this stuff i say i have done. i am also a believer in gaining hp by saving it. engines are just air pumps.


parasitic drag can be lowered. and it can be cheap.

a oil seperator and electric vacuum pump. i can't remember the limit of vacuum, but when you get a lot of oil running out of the pump outlet, you have too much.

the best windage tray, vacuum pump, electric water pump, true scavanging stepped header, 5w25 oil, 50,000v pulsed ignition, multi electrode plugs indexed to point at the exhaust port, etc.. etc.. etc..
 
^Thanks, and I did some digging...max you should run is 15"s. For street they say 10-12"s. If you go above 15, then it reduces oil spray and will limit piston wall/rod bearing oiling.
Im trying to find a good vaccum pump, but we cant run a belt driven run one :(. But my 66 can :D haha.
I have some of the stuff you listed - the indexed sparkplugs...but they are side gapped. I also want that plasma booster ignition.

I been wondering if my rerigged PCV system is hurting my cars HP :shrug:. I made the hose smaller and put an oil seperator inline...I also connected the 2 hoses into 1 going into the plenum...blocked the CAI vaccum hole. But I doubt our cars pull much vaccume @ WOT....maybe an inch or 2.
 
So ill take that as its not pulling much vaccum at all on the PCV system lol. So I doubt there is any HP difference beteen having breathers in you valve covers VS hooking up a PCV line.
BTW its a 750 might demon carb thats going on.