CAN I USE MY GT40p HEADS on my street mustang and be \"smog friendly\"?

CAN I USE MY GT40p HEADS on my street mustang and be "smog friendly"?

HI! I just got a FOX-Bodied Mustang! All of my other cars were carb. I have GT40-p heads. I have full length tube-headers with O2 sensor bungs. CAN I BE LEGAL using these heads living in CA? I have read that the GT 40p heads were made in such as way as to be able to smog the 5.0 with the newer (at the time) laws - therefore the heads were revised to be cleaner, more efficent, deleting the need for the smog pump. Is this true?

If I JB weld the air tubes to the heads to pass visual check will I pass the sniffer?

**Yeiks!!**

(here is my new car): http://www.cashiercentral.com/chp87/chp-87-mustang.htm
**...**
(my buddies car here): http://www.cashiercentral.com/Sn95/index.htm

The heads should already be smog ready. What you may be asking is how to hook up the exhaust feed to the crossovers at the back of the heads?

I had the muffler shop weld a 1/2 tube to the cross-over between the dual exhausts, then bent the tube to the general area of the fitting and connected the two with the shortest piece of heat resistant neoprene hose I could use to close the gap.

If you are missing all the other vacuum fittings and other stuff...you are on your own. I cannot even begin to tell where to find replacements and they do check to see if its there and operational.

The test is to pull the vacuum fitting...the engine rpm should drop around 100- 200 rpm if it is working correctly...that's how they catch you if you just make it look like its working.

_________________
They that can give up essential liberty to obtain a little temporary safety ... deserve neither liberty nor safety.
-- Benjamin Franklin

<font size=-1>[ This Message was edited by: Beoweolf on 3/26/05 9:33pm ]</font>

Beoweolf, thanks for your reply. I am new to fuel injection &amp; smog requirements, but I don't believe that the GT40P heads came with the air injection in the heads... mine have no thermactor bumps in the exhaust port... no holes in the back of the heads to bolt that weird air-pump-hose on. I don’t know exactly how everything in the fuel injection system works together yet, but my heads are missing the two little tapped out holes for the small bolts and the little hole that usually has carbon build up bad - "cholesterol build up" where it connects to the hose in question. Maybe I’m misinterpreting your response, sorry if I am.

My '87 has a COMPLETELY stock speed density set up on it now. I want to convert to mass air (70mm MAF, 65mm TB) with a different mill in mind..........an engine I’ve got built, but it WAS gonna be in a carb. application. (I wonder if the f-injection can handle 9.8:1 cr?)

I’ve seen people selling the GT40P heads with oversized valves and drilled out for some smog equip. BUT I FAIL to understand how they can duplicate the E7TE heads where there is a hole in EVERY exhaust port! I suppose you drill once into each exhaust port and then drill one really long hole connecting all those other small holes together? Is that what I am expected to do in the eyes of the "SMOG LAWS". which seem to be LAWS, true, but not always necessarily about smog or pollution!

From what I’ve read, the revised spark-plug angle and re-designed exhaust got the 5.0 cleaner, removing the need for the air injection at the time. I was hoping to utilize the benefits of the P head (which are completed) without getting them drilled up?


<font size=-1>[ This Message was edited by: 67fastback on 3/26/05 8:53am ]</font>

Unfortunately, I don't have a set of GT-P heads to look at. But I did have a set to world product heads (Jr.'s)...they had a dimple in the exhaust port, that showed where to drill into the passage to activate the smog ports. If you live in Ca, that is a good reason to get WP heads, they may not give Ultimate power, but they can be made smog legal and if ported are pretty potent on the street.

Take areal good look at the heads, see if if there is large hole, about 1/2 inch with a smaller hole above it, tapped for a 5/16 or so bolt. I know ford did some tricky thing in the last years of the 5.0 liter production, but I am surpriced to fing they didn't make those heads capable of being retro-fitted to earlier models?

I have seen many articles for swapping them on 5.0 engines, I didn't pay a lot of attention to them, since I had already made my decision. You might want to check the Tech section see if they have an article on the swap.

[addsig]

I had one of the first set that came out in 97.They werent smog ready .
[addsig]

Have to defer to the man with hands-on, "eyeball", experience. You could not find the smog ports and above poster confirms they didn't cast them in the head.

Apparently you figured it out...Guess they got the smog calibration down enough to clean up the exhaust without recirculatiing exhaust through the heads.

So at least for California, for the 5.0 HO engines, if you want to remain smog legal, you can take the GT-p heads off your list.

_________________
They that can give up essential liberty to obtain a little temporary safety ... deserve neither liberty nor safety.
-- Benjamin Franklin

<font size=-1>[ This Message was edited by: Beoweolf on 3/26/05 9:37pm ]</font>

got this other response from "quietflow"

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"You should be able to pass smog test just fine. You will still need the air pump going to the convertors. But the part that goes to the heads will not be needed. The divertor valve in the smog hoses diverts cool air from the air pump to the cyclinders to trick the O2 sensor to richen the mixture during cold start. Once warm the divertor vavle send the air from the air pump to the convertors to make them burn cleaner and more efficent. The heads not being drilled for smog should not effect emissions since the test is done with the vehicle warm. But you will still need the air pump to pass."
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Waydda you guys think of the above? It seems damn positive to me!!





(buddies car: )
http://www.cashiercentral.com/Sn95/index.htm

One suggestion would be to take a look at a 98 Exploder with a 5.0 and use that as a visual reference. That should give you a visual requirement and go from there.

Just my $.02

I just pulled heads of a junkyard 98 explorer in CA and it didn't even have a smog pump! However to pass visual inspection in CA you need all the smog stuff to at least look like the under hood smog sticker. That means you need to drill and tap the P heads for the air tube in back. My smog guy has never messed with the A.I.R. system on my 85, only the vac advance to check the timing.

One more issue with P heads is they don't have internal EGR after the 97 model year. Exploders 98 and later routed the exhaust gas from the exhaust header with a steel tube. At least one smog man I went to put vac to the EGR valve to see if it slowed down the idle. This means with 98 and later P heads you need to rig something to make the EGR work. By the way EGR improves highway gas mileage about 5 mpg, and it shuts off at wide open throttle so it doesn't affect performance.The sniffer test is done on a dyno at 15 and 25 miles per hour, they no longer measure idle emissions. This is a condition where the EGR had to work to keep down Nox emissions which, they do measure now. If your cylinder pressures are low enough and front (3-way, HC NO, and Nox) cats are new, it may pass anyway, but if it fails on Nox the repair guy will look at EGR first thing. That would leave you to self repair before a retest. Best way to avoid all this is to use 96-97 exploder heads, they have internal EGR same as E7's
I'm going to try to drill internal egr passages in my P heads, and failing that, add external EGR tubing to my headers a la exploder. I'm trying to confirm that 94 95 headers have the fitting for external egr but I doubt they will clear the spark plugs on P heads. Also any headers will have to have a carb EO number to pass visual.

One more issue with CA smog is your H-pipe. Starting in 09 you may only replace catalytic converters if they cause the car to fail smog. The replacements must have the exact number and placement of cats as the stock pipe as well as O2 sensors. All previous EO numbers are revoked and it is no longer legal to sell or install aftermarket performance H-pipes in California. The smog nazis even send spies to the shops to see if they will install illegal parts. As of November 09 I don't see high performance (bigger than 2-1/4") pipes with a Carb number. Your old high performance H will pass if it was installed before 09. But perhaps this is a subject for a different thread.....