1rocket, i did the same loop tube thing too. Except that i added a mixture
of antifreeze and water in to the tube with the wives ex- turkey baser before
i connected it up.
this way it keeps it from freezing up in winter. but i still get the better
throttle response with out all the hot fluid running through it.

 

I was reading your post about the gains from blocking the EGR, and was wondering whether you have mass air flow or speed density fuel injection. I have speed density and am not sure that the system would react well to having less air flowing through when it expects to have some recirculated air going through also. MAF would account for this though I think.

 

Kd5kuu, I was wondering that too. The proccessor reads the position of the open EGR valve and subtracts the value for exhaust gas from the total volume going in to the cylinders. Would this cause a rich condition with the EGR flow cut off?

 

[updated:LAST EDITED ON 24-Sep-02 AT 10:48 PM (EST)]If you look (do a search if you want) at an earlier post on this I said leave the electrical part of the EGR hooked up. Just disconnect the valve part from the connector part and leave it hooked up the computer will read a bad EGR and will compensate for it at least that is what I was told and it seems to be working fine on mine. Hope this helps and Good Luck,

Rick
86 302 EFI, bored 60 over, AOD,
Headman Headers, Flowmaster 40 series,
2 inch dual exhaust, MSD ignition

 

I think you are a little confused on the EGR setup. The EGR valve introduces exhaust into the intake manifold at wide open throttle to try and burn any remaining fuel in the exhaust. If you have ever opened the EGR valve at idle, you will have noticed that the engine stalls quickly.

When the EGR valve opens, the intake vaccum pulls a small amount of exhaust gas into the intake to burn, and in turn does pull in a slightly less amount of fresh air. Since you are eliminating the EGR gas introduced into the intake manifold, your fresh air volume into the throttle body is maintained. The mixture will be slightly leaner, as there is more fresh air for the same amount of fuel. Any changes in air/fuel mixture will be accomodated by the O2 sensor, and the computer will change the amount of fuel delivered to make the mixture correct.

Overall, the result is slightly more air and fuel at wide open throttle. The EGR mod doesn't change the idle or low end performance at all. In my opinion, adding the exhaust gas is like "watering down" the air/fuel mixture. Eliminating the exhaust gas provides a faster burn, which translates to more power and better mileage.

 

The reason for an EGR system is to lower the temperature of combustion. This reduces NOX emissions. There is a chance that if you disable it, you might get pinging and need higher octane fuel. Just something to think about.

Jim

 

[updated:LAST EDITED ON 30-Sep-02 AT 09:18 AM (EST)]i have a 95 bronco with 5.0 4x4, all stock no chip. im not sure which air sensor i have but i can tell you this, that set up wont be emission legal but i have had no problems so far. even using cheap gas with the a/c running have not had a pinging problem. this eliminated my surging on warm up, it idles better and the seat o meter noticed a big gain. i did leave the electrical connector hooked up just put a spacer in the egr line that connect to the egr. hope this helps.

 

This mod. woke up my 95, and easy to do.

 

Everyone keeps talking about off-the-line times, throttle response, top-end, and more HP...noone has mentioned mileage. Did anyone see any increase in mpg?

 

not sure if the gas mileage went up. i did so many tune ups on it which helped some, but the other cheap mods worked better. i get 15 mpg in town with the a/c and the motor has 112,000 not sure on the highway havent taken it on a road trip.

 

Never would of thought posting this would have been such a huge topic and so far everyone seems happy with there broncos after doing it.

 

Hey

I did the coolant line bypass, and it seems to run a bit better. Where exactly is the EGR line or valve that i need to bypass in order to do this?

Is it the cylinder shaped object with the electrc plug running to it?? I sound so newbie, but i have no idea what im looking for. If someone has a picture, i would appreciate it a ton.

Thanks in advance

 

[updated:LAST EDITED ON 28-Oct-02 AT 12:29 PM (EST)]yes it is the cylinder shaped object that is silver attached between manifold and the throttle plate. it has about a 3/4" diameter tube maybe a little smaller, tube connected at the bottom and a electrical plug at the top. just disconnect the tube use a wafer out of a electrical wall socket outlet box and lightly grind off a little so it will fit you can use one or two. leave the electrical plug hooked up. hope this helps good luck.

 

Yup I stopped the hot coolant flow by installin a one way valve going to the throttle body.....

It is there to prevent icing on the TB assembly during winter months.....

I went with the valve because I take trips to Aspen, CO and Tahoe/Reno Nevada often...

THe 5.8 is quite peppier....

 

>It is there to prevent icing on the TB assembly during
>winter months.....

Is it really and have you ever experienced icing?? I'm not so certain this would really happen. I'm not familiar with Bernoulli's principle that Rick mentions but maybe I'll try a web search.