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Topic: 5.0 TC Airbox or 50 state K&N kit (Read 2830 times) previous topic - next topic

5.0 TC Airbox or 50 state K&N kit

I have now brought my 88 5.0 TC to CA and need to get it ready to pass emissions...  I'm thinking I either need to get a stock TC airbox and make a custom intake tube to connect it to the HO upper OR find a 50 state legal K&N Fuel Injection Performance Kit (all of with hold CA exempt numbers to pass visual inspections) that can be made to fit the car.  Anyone have any experience or ideas?
1988 Thunderbird Turbo Coupe
'89 5.0 w/ ported intakes, Mallory Adjustable FPR, BBK shorties and H with 2.5" Flows, 130 amp 3G, 89 Mustang comp/wiring, Aluminum radiator w/ elec fan, T5 trans, King Cobra clutch, 3.55 gears, 13" Cobra brakes (front), Wilwood prop valve, Mustang A-arms, Front Coil-overs, MM CC plates, Silver 17x9 R's, 03 Cobra IRS, Aluminum DS, 2002 Mustang dash/console etc..., custom leather seats

5.0 TC Airbox or 50 state K&N kit

Reply #1
it wont pass in cali they inspect under the hood as soon as they see the 8 it's a fail. well i belive it to be like that hear all the cali mustang guys swaping parts back for smog
trick flow street heat intake , 24lbs injetors, ported GT-40's (Chip) long tube headers. and a Performance Automatic C4, with a hurst shifter!

5.0 TC Airbox or 50 state K&N kit

Reply #2
i was told that you just have to get a referee (?) to check it out... and since they did offer some kind of 5.0 in an 88 thunderbird it should be considered motor replacement...  I was worried about a visual fail but I don't how how they can do that.  What if some clueless dude buys a car unknowing there is a motor swap and then moves to CA? 

I guess my other option would be to figure out how to keep out of state plates?  But WI may be to far, I'm assuming insurance will be a whole issue there also...
1988 Thunderbird Turbo Coupe
'89 5.0 w/ ported intakes, Mallory Adjustable FPR, BBK shorties and H with 2.5" Flows, 130 amp 3G, 89 Mustang comp/wiring, Aluminum radiator w/ elec fan, T5 trans, King Cobra clutch, 3.55 gears, 13" Cobra brakes (front), Wilwood prop valve, Mustang A-arms, Front Coil-overs, MM CC plates, Silver 17x9 R's, 03 Cobra IRS, Aluminum DS, 2002 Mustang dash/console etc..., custom leather seats

5.0 TC Airbox or 50 state K&N kit

Reply #3
Ok, I just read up a little more.  From what I gather, you just have to swap in a same year or newer engine with all smog gear and one that was offered in a similar car (truck, small car, etc...)  But in the end, thie biggest thing is that it doesn't pollute more than the other engine.... 

anyway, anyone have an idea?  I'd love a cold air induction pulling from the fender well...
1988 Thunderbird Turbo Coupe
'89 5.0 w/ ported intakes, Mallory Adjustable FPR, BBK shorties and H with 2.5" Flows, 130 amp 3G, 89 Mustang comp/wiring, Aluminum radiator w/ elec fan, T5 trans, King Cobra clutch, 3.55 gears, 13" Cobra brakes (front), Wilwood prop valve, Mustang A-arms, Front Coil-overs, MM CC plates, Silver 17x9 R's, 03 Cobra IRS, Aluminum DS, 2002 Mustang dash/console etc..., custom leather seats

5.0 TC Airbox or 50 state K&N kit

Reply #4
You can use a stock Mustang air box setup if youre MAF, or a stock tbird setup if speed density.
It's Gumby's fault.

5.0 TC Airbox or 50 state K&N kit

Reply #5
I'm running mass air (89 stang computer/wiring).  So I guess that means aftermarket cold air intakes will work, too.  Just need one with a CARB number.  Thanks!
1988 Thunderbird Turbo Coupe
'89 5.0 w/ ported intakes, Mallory Adjustable FPR, BBK shorties and H with 2.5" Flows, 130 amp 3G, 89 Mustang comp/wiring, Aluminum radiator w/ elec fan, T5 trans, King Cobra clutch, 3.55 gears, 13" Cobra brakes (front), Wilwood prop valve, Mustang A-arms, Front Coil-overs, MM CC plates, Silver 17x9 R's, 03 Cobra IRS, Aluminum DS, 2002 Mustang dash/console etc..., custom leather seats

5.0 TC Airbox or 50 state K&N kit

Reply #6
Dunno if it has CARB exemption or not but I'm running the BBK cold air system... Had to cut a couple inches off the upper section to get it to fit properly, but otherwise the Stang unit was a bolt on...

See pic from link in my sig..

5.0 TC Airbox or 50 state K&N kit

Reply #7
So I'm assuming you trimmed it off on the MAF side of the tube that goes to the upper...?  Then I guess I could find whatever has a CARB # and can be trimmed in that manner...  Or perhaps for now, I can get a stock mustang airbox easy and free...  But thanks, it's good to know the aftermarket stuff will work, too!
1988 Thunderbird Turbo Coupe
'89 5.0 w/ ported intakes, Mallory Adjustable FPR, BBK shorties and H with 2.5" Flows, 130 amp 3G, 89 Mustang comp/wiring, Aluminum radiator w/ elec fan, T5 trans, King Cobra clutch, 3.55 gears, 13" Cobra brakes (front), Wilwood prop valve, Mustang A-arms, Front Coil-overs, MM CC plates, Silver 17x9 R's, 03 Cobra IRS, Aluminum DS, 2002 Mustang dash/console etc..., custom leather seats

5.0 TC Airbox or 50 state K&N kit

Reply #8
Yes I trimmed it a bit at the MAF on the T-Body side... Ran a stock air box and Stang MAF elbow for years... Since you're going for an exemption I believe I'd try to make it look "stock" as possible. You can always go aftermarket in the future...

5.0 TC Airbox or 50 state K&N kit

Reply #9
Where in CA are you at? Here's what I know from personal experience and maybe it will help:

First off, I knew a mechanic who told me which smog stations to go to and if there was ever a question of weather it would pass or not, he would take it in for me. As long as it was tuned and running well I passed. As long as I tested below the limits of a 5.0 SO I could theoretically do whatever I wanted (not talking visualy passing). Which is why I could run a supercharger and pass the sniffer but visualy fail because 50 state legal superchargers are usually only for mustangs.

I got away with an engine swap because my Sport had a 5.0 SO and I went to a HO & MAF. First time I smoged it, it was all stock, including a 4 cat mustang h-pipe, stock y headers, and stock airbox. By the next time it had to be smoged, I had a cobra upper and lower intake, k&n style air intake, 2-cat x-pipe, pullies, etc. Visually the guy didn't even look surprised when he opened the hood. All they should really care about is the emissions.

CA is py no matter how you look at it. 50 state legal stuff for Fox Mustang guys technicaly isn't legal for us T-bird/cougar guys despite the relationship between the two cars. Law says if you had 7 cats on your car, you better have 7 everytime you get a visual check; If your car came with an 8 cylinder engine, you better have an 8 cylinder engine. That's where I'm worried for you. Even though what you said about having a same or newer engine is true, I don't know about changing the number of cylinders. I'd look around for shops that work on mustangs and ask them to test your car before you have it "officialy" smoged. If you find a cool enough place they might guide you to a smog station that will "overlook" certain "flaws" pertaining to parts that should or should not be there. As long as your "sniffer" score does not exceed the numbers of a 2.3T you should be alright. Let us know how everything goes. I wish you goodluck.

5.0 TC Airbox or 50 state K&N kit

Reply #10
hey Bduly, thanks for the response, VERY helpful.  I'm in North County San Diego: Rancho Penasquitos to be exact.  I got info from a supposed smog expert on stangnet who said a ref can just lisense it as a fox mustang and I'll be cool.  But I'd love to maybe talk to the mechanic you talked to.  I'm new to all this smog stuff so I will need all the help I can get!  Thanks again, I may be asking a few more questions if thats ok...

and btw: I love your sig pic, car looks amazing!
1988 Thunderbird Turbo Coupe
'89 5.0 w/ ported intakes, Mallory Adjustable FPR, BBK shorties and H with 2.5" Flows, 130 amp 3G, 89 Mustang comp/wiring, Aluminum radiator w/ elec fan, T5 trans, King Cobra clutch, 3.55 gears, 13" Cobra brakes (front), Wilwood prop valve, Mustang A-arms, Front Coil-overs, MM CC plates, Silver 17x9 R's, 03 Cobra IRS, Aluminum DS, 2002 Mustang dash/console etc..., custom leather seats