I just installed a corksport cat back on my 88 NA. before that i just had the stock cat-back with racing beat header and presilencer. just the catback was replaced to corksport. but anyway... after installing it, i swear ive gotten a drop in power. i dont accelarate as fast. it seems like it. anyone have some input on this? oh yeah, and it is extremely loud, very loud. and its extremely hot, like i went on a short trip (5miles) and when i looked under the car, heat was pouring out. is that safe? thanks for any help you can give me.

 

It may be TOO free flowing an you may not be able to open your ports anymore. Check if they are still working.

Santiago

 

how is that done?

 

you can put some greas on the port actuators and go for a good fast drive for like 15 minuts then chack to see if the grease moved.

 

you can put grease on the rods and then go for a spirited drive. After check to see if the grease moved or was smudged.

 

thanks. and if it does move? or not?

 

it moves if ur ports are working if not then they are not working. Do the test first and then go from there.

 

thanks

 

does this mean that i have to remove my entire header and stuff?

 

no you dont have to remove anything if you are just checking your ports. just put some grease on the shaft of the acuator and drive around the block, take it to 7k RPM a couple of time go back and see if the shaft that goes into the acuator has moved the grease it not hard. if they dont work any more just zip tie them open and your good to go.

 

i dont want to sound stupid, but where is this?

 

wiring the ports open will make you lose low end power. I suggest trying to have the ports working correctly so you have the correct low end and high end when you need it.

 

 

to the left of that shiny plate....except you'll have a actuator on it.

 

how did your car feel wtih the header/presilencer with the stock catback. i am considering doing this until i get the money for a new catback

 

opening the ports doesnt kill your low end power very much, i dont know why everyone says that, it just drops low end a little bit, not enough to be drastic at all, and with pineapple sleeves its almost 0 drop.

 

The question is, why wouldnt you want them working. Unless you are taking out the rods and smoothing it out, so that it flows nice there is no reason to not getting them working other than you just dont want to. They are there for a reason, just get them working.

 

I think your talking to the other guy....but I'm running midas mufflers...essentially stockers....it sounds like a 2 stroke...but I noticed a nice gain from 4k on...I'm running rb header/pre-silencer...2.5 to midas mufflers that were on the car.

 

I'd much rather have mine working off the actuators....

 

Agreed about the power loss at lower RPM.

 

Since you have an 88 you will need back pressure to open your ports, which I bet are not working because your exhaust is so free flowing. Goto http://www.rotaryresurrection.com/ and look under the Tech section for Air pump 6pi. That will explain how to get your ports working. However if you took your Air Pump off becuase of your headers(Which I bet is a yes), then let us know.

 

I agree

 

Pretty noticable drop on every one I have done that too, perhaps yours were not functioning correctly to start with?

 

yeah, now that ive taken it up to more speed, the low end is pretty much all that dropped. and thanks again, a lot

 

i dont know, all of mine that i got had them frozen shut, and i always just put them in open position, and even with the A/C on there isnt a big loss in the lower RPM range, i agree it does drop lower rpm power, but it isnt so drastic that you cant drive in the lower RPM's even with the A/C on. i mean i go over a mountain pass at least twice a week that goes from 4900 ft up to 8600 ft at the top, and i can use the a/c with the ports open and be in 3rd gear at 2k rpm and still gain speed when i depress the gas pedal even half ways. i just havent noticed a big loss in power in any of the applications ive used.

i will say however that with the ports working properly that it works really well, as my first n/a that i owned had working ports with a couple other mods and it ran 14.1's all day so its pretty much up to if you want to lose a little low end, and probably sacrifice some gas mileage on a cruise or make a setup with the air pump, but you can also use the ACV vent hose as i did on the n/a that i had with working ports, the ACV vent hose vents at 3800 rpm and has enough pressure just to start opening the ports and at 5000 enough to keep them fully open, so its a much easier mod than the air pump, all you gotta do is drill a hole into the pipe the same size as the 6 pi actuator hose at the bend on the pipe and make sure the hose gets put in facing the ACV so it gets that vented air to open them