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I have pretty much collected almost all of the parts for the Ford V8 conversion, however my 85' 240 is also getting close to NJ inspection time in November. I am planning to perform the conversion after I have the car inspected with the original engine sometime in September, since I am in NJ I can have the car inspected 2 months before the actual inspection month.
Also I will be leaving overseas next year(Europe) and I am planning to bring the car with me and there I will register it as a classic(20+ years old). This will NOT be a daily commuter car. On the other hand smog laws there are much more relaxed and having a catalytic converter is good enough. I doubt if people know what a smog pump really is.
As far as the emission functionality goes I have the following question. Keeping the conversion 100% legal will it actualy make my car run better, get better milage and be much cleaner? If not what kind of tradeoffs can I take for example by eliminating the Smog pump/hoses and keeping only the charcoal canister and catalytic converter and EGR? I know that most of these emissions equipment play a major role during open loop operation (Warm-up) and a minor rule during closed loop. This means that they do not make alot of difference in a smog station enviroment where the car is already warmed up and sitting at the line waiting for inspection.
I just need to also sort this out before the conversion....
Any suggestions?
Thanks
Mike
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Well, you've kind of got it backwards. All of that emissions stuff is only working when the car is warmed up and in closed loop. The cat(s) don't work when 1. they are cold and 2. when the air/fuel ratio is not around lambda, as it should be when in closed loop. That's why you've gotta be warmed up when you go into inspection.
The canister is also purged after the engine warms up, and EGR and possibly the air injection only work once warmed up as well. It's noteworthy that most or all of the emissions stuff is also not used at full throttle, which is also open loop. So EGR is not something that will affect performance. From what I hear, the air pump does not take a lot to run, so that won't affect performance either.
As far as running "better" or gas mileage, I don't know if the emissions devices will make a difference or not. The only system that I would imagine might make a difference there is the EGR, but I don't know in what way.
I would just keep all the emissions stuff. Possibly it would be nice to get rid of the smog pump system just to clean up the engine compartment, but since mine is installed already, I don't plan on removing it.
I have all the systems in place, and recently went through the Massachusetts smog test, which is at varying speed on a dyno. Here are the results:
HC grams per mile 0.47, limit: 2.00
CO grams per mile 0.79, limit: 30.00
NOx grams per mile 0.65, limit: 3.00
CO2 grams per mile 412.27, limit: NA
My engine is a 306 with 10:1 compression, and all the usual bolt on stuff, TFS heads, Crower "11" cam, TFS Track Heat intake.
Just a note, the limits above are for the chassis, 1990 240, and the smog test doesn't do WOT (or test at idle AFAIK).
Greg
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http://home.earthlink.net/~greg.wong/
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I would add to Greg's answer that the smog pump is there to provide excess oxygen into the exhaust stream so the cats have what they need to complete chemical reactions that convert measured emissions unburned HC's, CO and NOx to H2O and CO2. Without the smog pump, many folks find that the cats aren't as effective, and without lightoff of the cats, they can tend to clog up and fail sooner. Moral of the story - if you run the cats, run the smog pump.
EGR serves to reduce combustion temperatures allowing the computer to pull fuel (lean) and add timing at light loads without the risk of detonation. That's how it reduces emissions (lower combustion temps reduces NOx; recirculating some exhaust reduces unburned hydrocarbons) and increases fuel mileage (lean burn). Since it's not active at w.o.t., removing it doesn't increase performance. And, removing it without altering the ecu can cause detonation in some cars, not to mention it sets error codes and lights the check engine light. Error codes and the check engine light will often shut you down in an attempt to pass emissions depending on the rigor of the testing protocol.
I agree with Greg - if you're gonna have to pass emissions with it, best to leave it all on -- it's designed to work as a system.
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On many cars the AIR (Air Injection Reacton in GM speak) pump send air upstream of the cat when the engine is cold to crate afterburning in the exhaust manifold to:
A) burn some of the rich startup mixure
B) warm the cat(s) to operating temperature more quickly.
The air pump is a pretty low pressure device, and i think its peak cost is bearing drag, folowed by weight of the bracket. Bearing friction might be one HP at max RPM, if it bothers you, replace it with an electric unit from a late 960 or 850.
(it seems to me the beaarings in these thigs are kind of crappy, and they might not last long if you rev over 7000 or so? anyone have experience with this?)
THe Air pump soed cary the advantage of saving you from havin to reconfigure your pulleys...On my no cat car, one of the AIR pump impellers seized 3 days after I did my conversion. I opened it up, and took the vanes out, now it is just an elaborate idler pulley. since i had no cat or air fittings in my manifolds to start with, i didn't lose anything. The system will somewhat wotk without teh vanes if teh chec valves are in good conditon....the Chrysler system works without a pump(uses exhaust pulse scavenging and check valves). You might be able to get away with adapting it to another car, but I have never tried.
KEEP the PCV SYSTEM
this emission system was developed by IHC around 1957, and trebbles the life expectancy of your engine with no harmful side efects.
The canisster purge system:
In the real world, all this does is keep your car from reeking of exhaust fumes on a hot day. 0 power loss, weight under a pound, and not active at WOT.
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Haha, yeah, actually I just replaced my air pump, because it was making noise. It doesn't seem like it was a bearing problem though, it felt more like a vane was catching. (You could feel it hang up when you tried to turn it)
The rebuilt part was only about $40. If I had gotten an air pump deleter pulley, that would have cost double! And you'd still have the bearing drag. (Low, I know)
That is a very cool idea to use an electric one from 960, I didn't even know those cars had one.
Greg
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asdfas
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You don't need a deleter pulley - just a shorter serpentine belt. :)
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Oh. So how come everyone sells these dang deleter pulleys? Just trying to make a buck?
Greg
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asdfas
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I'm as surprised as you - don't know why. Just remove the pump, and then get an 83.5-84.5" belt. Mine works just fine - alt/water pump/p-s/a-c and the shorter belt.
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When you use a March p/s, air pump delete conversion, sometimes the belt will not wrap around the alternator pulley enough and it will slip. Thats when you can use an extra idle pulley to make the belt wrap around the alternator some more. Also, I have used Goodyear Gatorback belts the last couple of years and they really work better than any other brand I have tried.
Cheers,
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How are they beter? I've been using a Ford Motorcraft one. When I put it on, the indicator on the tensioner was toward the end already, and now it's even closer. It doesn't seem like it's going to last long. Maybe it's because of the underdrive pulleys.
How long do you wait to change yours? Isn't the interval pretty short, like 20k miles?
Greg
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http://home.earthlink.net/~greg.wong/
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I've used 5 belts since I first put the car together but mainly because I have deleted various accessories. I have only put about 16k miles on the car since "new". The Gatorbacks have better "traction" and run cooler. It is the only belt that worked with my March delete conversion.
Cheers,
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