the air cleaner housing.
CK5
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performer intake
- Thread starter carolinafan4life63
- Start date
GM did it on some of their engines. I see what you are saying, but I'd rather have a set screw loc-tited flush with the base of the intake than JB Weld, which I've personally had fall off when used on non-pressurized (to seal mis-threaded accessory bolt holes) portions on heads.
No question weld would be best if an option. Probably not worth all the effort for an intake that probably cost $150 new.
No question weld would be best if an option. Probably not worth all the effort for an intake that probably cost $150 new.
Not sure how GM would plumb super heated exhaust gas into the air cleaner without lighting the air cleaner on fire.
To my knowledge no GM '91 and older was ever setup other than the exhaust gas being dumped directly into the intake. As an example, my TPI base has tiny holes drilled in each port for EGR.
To my knowledge no GM '91 and older was ever setup other than the exhaust gas being dumped directly into the intake. As an example, my TPI base has tiny holes drilled in each port for EGR.
that makes sense, to port it into the airflow; to have it shooting straight up into the primary venturies of a carb does not. On the note of super heated air catching air filters on fire; I am fairly certain atomized fuel has a much lower flash point then paper.
carolinafan4life63
1/2 ton status
ok so what would yoou guys personally do? i dont have access to a welder so its either gonna be j-b weld or tap and bolts with threadlocker! gonna try and get it up and running tommorrow(hopefully), i figure either way i have a chance of getting a visit from murphy , just trying to find out the better alternative, thanks for all the input guys
id personally replace it with a differnt one new or used what ever the funds call for.
Hot air keeps fuel atomized, this is why GM actually did it that way.
original balzer
1/2 ton status
LOL I dont know for sure but it sounds like some of you guys think those holes are supposed to be there. I have delt with tons of chevy intakes of all differnt brands and I know for certain those holes are NOT supposed to be there.
I personally would check with a steel straight edge along the surface that bolts to the head. Most used alum intakes warp in this area. If that isnt flat and true drop the intake into the recycling bin. If it is strait and can be used use bolts(with a head) tap the hole and either JB weld the threads or use red loc tight.
And heres why, the bolt head gives a friction surface to hold in there. The allen head plug only has threads to hold it in there. A clump of Jb weld doesnt seam like a secure way either, it could just get sucked out of the smooth holes.
Use a bolt with a head and make sure the threads of the bolt go all the way up and bottom the bolt head out on the inside surface of the intake.
EGR on older small blocks DO NOT route the exhaust back into the intake. This goes for anything older than vortec engines. The EGR on older small block simply passes exhaust through the heads and intake to help the engine warm up in cold weather.
BOTH of those holes on the right side of the intake are for thermal choke assemblys. Neither routes exhaust back into the combustion cycle.
I personally would check with a steel straight edge along the surface that bolts to the head. Most used alum intakes warp in this area. If that isnt flat and true drop the intake into the recycling bin. If it is strait and can be used use bolts(with a head) tap the hole and either JB weld the threads or use red loc tight.
And heres why, the bolt head gives a friction surface to hold in there. The allen head plug only has threads to hold it in there. A clump of Jb weld doesnt seam like a secure way either, it could just get sucked out of the smooth holes.
Use a bolt with a head and make sure the threads of the bolt go all the way up and bottom the bolt head out on the inside surface of the intake.
EGR on older small blocks DO NOT route the exhaust back into the intake. This goes for anything older than vortec engines. The EGR on older small block simply passes exhaust through the heads and intake to help the engine warm up in cold weather.
BOTH of those holes on the right side of the intake are for thermal choke assemblys. Neither routes exhaust back into the combustion cycle.
Not air hot enough to catch paper on fire! 451F will light gasoline as well.
I am very curious as to why someone would drill those holes that way.
I am very curious as to why someone would drill those holes that way.
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Uh, you are absolutely wrong. My post was stupid as hell (I was in a hurry and didn't get to think on it) but EGR does not simply pass under the intake. FWIW I believe the truck EGR systems rely on vacuum to pull it into the intake, therefore into the air cleaner wouldn't work. The simple fact of routing it through the intake was likely a cost saving measure, as well as having nothing but the valve itself to fail. No hoses to leak, etc.
I'm not going to even spend the time dredging up a plethora of information on how EGR works, and has ALWAYS worked (as it's everywhere on the 'net), suffice it to say, EGR has to make it into the incoming air/fuel mix before it reaches the cylinders. It has nothing to do with heating the engine up. That crossover on smallblocks was there before EGR was even used, which WAS solely for heating the intake up.
I'm not going to even spend the time dredging up a plethora of information on how EGR works, and has ALWAYS worked (as it's everywhere on the 'net), suffice it to say, EGR has to make it into the incoming air/fuel mix before it reaches the cylinders. It has nothing to do with heating the engine up. That crossover on smallblocks was there before EGR was even used, which WAS solely for heating the intake up.
carolinafan4life63
1/2 ton status
just finished installing the intake on the blazer! used red loctite and 3/8 bolts! took it for a test drive around 20-25 miles and it seems to be working pretty well! a lot more bottom end than the 7546 weiand intake that was on there that the previous owner had on it! thanks for all the input guys......this site is the best 25 dollars i have spent in a while...thanks again
original balzer
1/2 ton status
Woah a weiand 7546 is a single plane manifold.
Yea good for 3500-6800 RPM lol not much good for a every day 4x4, maybe a mud racer.
Yea good for 3500-6800 RPM lol not much good for a every day 4x4, maybe a mud racer.
original balzer
1/2 ton status
Well for what its worth both of our posts were off. The exhaust crossover is commonly called an EGR by people that dont know any better. And without thinking I used the term EGR in my post. But its clear by the pics those holes go straight into the exhaust crossover passage. That edelbrock intake is not a EGR version though. Hes got it all figured out now though so all is well.
Good call to point that out though lol.
carolinafan4life63
1/2 ton status
yeah , running great.....i guess the previous owner had that bigger is always better mentality.......lol. thanks guys
Well for what its worth both of our posts were off. But its clear by the pics those holes go straight into the exhaust crossover passage. That edelbrock intake is not a EGR version though. Hes got it all figured out now though so all is well.
So what is the mounting surface on the left in the picture shown in post #14? Right mounting surface is hot air choke, left side is....
OP states that air blown into those holes under the carb come out from one of the passageways in the left pad...this means?
original balzer
1/2 ton status
I dunno you tell me.
Casting number I'd think would tell if it was originally an EGR intake. Wonder if Edelbrock casts many of the intakes the same, and simply finishes the EGR ones with drilled holes. Easy to do, if the EGR pad is on non-EGR variants, the pictured one could simply have been modified by a PO.
BTW, the OP's pictures and description show how you would plumb EGR.
The EGR pad has one hole open to the crossover, one will go to those two holes. The EGR valve blocks flow between the two holes. When the valve opens, engine vacuum (or backpressure pushes depending on design) pulls the exhaust gas through the crossover, into the intake feed passages, to mix in the intake with the incoming air/fuel charge.
BTW, the OP's pictures and description show how you would plumb EGR.
The EGR pad has one hole open to the crossover, one will go to those two holes. The EGR valve blocks flow between the two holes. When the valve opens, engine vacuum (or backpressure pushes depending on design) pulls the exhaust gas through the crossover, into the intake feed passages, to mix in the intake with the incoming air/fuel charge.
original balzer
1/2 ton status
I stand corrected looking at the OP pic I didnt see the EGR AT THE TOP left side. I was thinking he was talking about the hole directly to the left center of the carb witch in fact is the exhaust crossover and the hole is for a thermal choke.
Sounds like he has it fixed though so it dont matter.
Sounds like he has it fixed though so it dont matter.
