Offy intake, Holley 390 and power brakes: Will I have clearance issues

[cuban11182]

ok get a infrared temp i have one for my r/c car it helps tune it, but anyway get a reading from the top of the intake...... then get a reading from when i have placed my air cleaner. there you go i dont have the reading off hand i don't remember, its also snowing outside. so when it clears up i'll send the data! i didnt believe myslef untell i did the temp gun. if you think about it the carb is sitting on a heater!!! drawning cooler air from the passenger side which dose not have a set of headers blasting heat straight up at the air cleaner.

dont get me wrong i realize the air warms up by the time it reaches the carb but still cooler then air cleaner on top the carb.

The only problem is you have to use the gun with the hood up. Once you close the hood down you get heat soak in the engine compartment. The entire engine compartment is hot. That's why most people have air coming from outside the compartment.

I have a temperature gun that I've used to check the water temps on the jeep when it running since my original gauge was . I've even tested resistors inline with my IAT on my truck and yes it does show a cooler temperature. Problem with it is that the colder air is more dense. So colder air, you can add more fuel and theoretically gain some HP. Problem is you're lying to the computer, it's compensating based on the perceived density of that cold air and dumping fuel. What you have now is a rich condition, not really any more power.

But if you're happy, I'm happy for you. I'll source alternative means if I need to get a different cleaner. I'll also spend my money elsewhere.

 

[Dan77CJ7]

The only problem is you have to use the gun with the hood up. Once you close the hood down you get heat soak in the engine compartment. The entire engine compartment is hot. That's why most people have air coming from outside the compartment.

I have a temperature gun that I've used to check the water temps on the jeep when it running since my original gauge was . I've even tested resistors inline with my IAT on my truck and yes it does show a cooler temperature. Problem with it is that the colder air is more dense. So colder air, you can add more fuel and theoretically gain some HP. Problem is you're lying to the computer, it's compensating based on the perceived density of that cold air and dumping fuel. What you have now is a rich condition, not really any more power.

But if you're happy, I'm happy for you. I'll source alternative means if I need to get a different cleaner. I'll also spend my money elsewhere.

ok i get. thanks. so if you have a 2150/287cfm? and want a holly 390? will you have a rich condition with the extra Cfm ? would that take away from the volumetric efficiency on a stock AMC 258 i6 / 4.2l with 4500 red line? i'm only asking i dont know, thanks.

 

[cuban11182]

ok i get. thanks. so if you have a 2150/287cfm? and want a holly 390? will you have a rich condition with the extra Cfm ? would that take away from the volumetric efficiency on a stock AMC 258 i6 / 4.2l with 4500 red line? i'm only asking i dont know, thanks.

Based on what I've read the 390 is the carb to go with if you want a 4 barrel. If you want a 2 barrel you go with the 2100 or 2150. I'm going to have both and will comment back on my findings.

 

[elwood blues]

I have ran a 1.08 cfm 2100, a 1.14 cfm 2150, a Demon 350cfm 2 barrel and a Holley 390cfm 4 barrel all on a swapped in stock 2 barrel intake, stock I had a 1bbl Carter w/ single bbl intake. Both before and after the COMP cam install.

Without question the Holley has provided the best power, throttle response and MPG (so long as you keep your foot out of the vacuum secondaries). The 1.14 cfm 2150 was a second in power and maybe just a little better in MPG. I will argue with anyone who says that the MC2100 1.08 is the perfect AMC 258 i6 / 4.2l carb, IMHO the 1.08 is maybe just a little too small of a carb, the 1.14 was a much better performance size, but they are harder to find. The Demon 350cfm 2 barrel consistantly ran too rich, no matter what I tried. It had a lot of potential, but those carbs really arent meant for what i wanted to do with it.

Dan77CJ7; I've been lloking at this one from Airaid for quite a few months now, if you have numbers on yours, I'd like to see them

 

[cuban11182]

Thanks Elwood, that gives me the warm and fuzzy. I've located an Offy for $125 that i have to look at when I visit my father at the end of the month. If it turns out that it's in good shape then I'll pick it up and the Holley.

 

[cuban11182]

Just ordered the 390. It won't be until early next month till I can install it. I'm going to have to decide if I want to put the Offy intake manifold on yet. I really don't want to have to take off the exhaust manifold only to find it warped due to heat.

 

[elwood blues]

Warping isn't a really big issue with the cast iron manifolds, they tend to crack instead

 

[cuban11182]

Sounds good. Thanks again.

Sent from my SCH-I535 using Tapatalk

 

[superj]

i will have to find a picture for you guys but i used an air filter assembly off a chevy astrovan for my holley four barrel. it allow me to buy filters anywhere and fits a normal four barrel size carb.


it seems like gr8dain's stock throttle cable assembly works well on the four barrel holley and offenhauser. that carb is mounted exactly how i mounted mine but my throttle cable keeps having trouble and i was going to turn it around but now seeing that, i might just get a stock throttle cable and try it out

 

[cuban11182]

Here is a video of it running. I'm going to tune it up, install the new hubs and a/c system this weekend.

https://www.youtube.com/watch?v=MseA0HZFO2w

After that it's a DUI and a Borla catback. That should hold me until I PCS out of here.

 

[gutthans]

Sorry about no pics but...I run an Offy Dual Plane with Holley 390, 9" dia filter (4" tall) with CJ dual diaphragm Booster ...No clearance issues 17.3 mpg when tuned for mileage on my 4.6 (4.0 w/ AMC 258 i6 / 4.2l crank).

I used a set of ski boat vents to ventilate heat from the engine compartment. $4 and about 2 hours work...drops temps by 30 - 40 degrees...also use a Flowkooler water pump...helps a bit over stock.

Oh, and that cable throttle sold at Autozone (Spectre, I think) adapts easily to the Holley on the Offy. You will need a stand-off bracket, but that's an easy fab to the rear corner of the carb mounting.

 

[gr8dain]

Here is a video of it running. I'm going to tune it up, install the new hubs and a/c system this weekend.



https://www.youtube.com/watch?v=MseA0HZFO2w



After that it's a DUI and a Borla catback. That should hold me until I PCS out of here.

Congrats. And by the way, i think I will go delete my pics. Your video makes me ashamed for my dirty engine.


Dain

 

[cuban11182]

Don't delete them Dain, my jeep was owned by old people before me. They like their stuff preserved, hence the reason for the plastic sheets on their couches.

Here is the start of the Jeepair A/C setup.

The heat index is 110 F today, so I'm going to wait till tomorrow to get more done. Then finish it up on Saturday.

 

[gr8dain]

110 degrees. Yuck. No wonder you are fixing the AC. I wouldn't even want to go outside.


Dain

 

[cuban11182]

It's not as hot as it was in the Middle East. I just can't stand this heat in Texas. I've been driving my Titan every day till the A/C is installed in the Jeep. Then the CJ will be the DD. I even bought the tool to crimp the hoses.