EGR mod

[jeepinGM]

Will a restrictor plate with a 3/16 - 7/32 hole work in my 4.3L? I have seen plenty of info for 96+ years but only unanswered ?s for earlier years.

After all the work I have done this summer on this swap this is the last mod I am considering before I get this thing fired up.

thanks,
jeepinGM

[stepside2k1s10]

couldn't tell ya, I got a 2.2, but someone will respond who has a 4.3 though.:crossfing sorry

[Maximus]

What year and fuel system is the engine?

[jeepinGM]

The engine is from a 92 Sonoma 4x4. Its a 4.3L with a comp cam .500 lift with 260 intake and 266 exhaust. Custom CAI with TBI and FI spacers. Advance Adapters headers with custom y-pipe and Magnaflow cat back.

thanks,
jeepinGM

[Mike 92S10]

Used 1/8" holes on my '92. Been running for about 3 years with only the occassional SES coming on. No problems at all. You'll love the mod. Oh, if it does give you a SES all the time drill it out a little bigger till it's O.K.

[XxInFaxX]

i dont remember the exact hole sizes, but yes, it will work and as mike said, if it throws a code, drill it out a touch bigger.

[jeepinGM]

Does the thickness of the plate effect performance? sheet metal vs a half inch thick plate with same size hole in it?

Thanks,
Mark

[Mike 92S10]

I'd be afraid of sheet metal. Too thin. You can get 1/8" steel plate at most home centers like Lowes or Home Depot. It's about 4" wide by about a foot long and fairly easy to work with. That's what I use. Like I said I've been running mine for almost 3 years. I've also made probably about 20 of these for other people.with no complaints. The 1/8" plate with 1/8" holes seems to work really well. Try this and see what you think. It's preety easy to change them out so play around a little if you want.

[jeepinGM]

The sheet metal was only to clarify about the thickness (I won't use sheet metal for anything on mine). I'm asking because I was a boiler/engineroom operator in the navy and I know that vacuum across a thin restriction won't change the vacuum level and velocity gained from a thin r. is lost almost immediatly. I'm not sure what effect I am looking for with the EGR mod. I know a half inch plate with 1/8 hole will restrict flow considerably more than a thin plate with a 1/8 hole.

jeepinGM

[Mike 92S10]

With the 1/8" plate and 1/8" holes I got some decent performance gains with no other problems. I get an SES light about once a month and it resets when I restart the motor. This seems to be a good combination for the early TBI motors.

[jeepinGM]

Thanks for the info I appreciate it. I will go with what works and maybe try a test on it later.

jeepinGM

[Mike 92S10]

Yeah I thought about trying different thickness plate and different size holes. But this combo worked so good I just didn't bother.

[jeepinGM]

Thats an answer I can live with pretty easy.

Thanks Mike

jeepinGM

[chesspirate]

Does anybody have a pic of where all this stuff takes place on a first gen??? I sat and stared at my engine and could not for the life of me figure out where the heck this thing is; otherwise the mod would be done by now! Thanks

[XxInFaxX]

on my 95 it is right behind the throttle body. not exactly sure where it would be on a 1st gen. but thats where is was on my TBI.

[Mike 92S10]

Yep on the back side of the TBI. My advice to anyone who wants to start working on theur vehicle is to go to the parts store and pick up a Haynes or Chiltons repair manual. Good pics and saves a lot of guess work.