My question is this, the stock q-jet mounting gasket on my lg4 stock intake was open (not 4 hole). I want to install a 1/2" phenolic spacer. Should I get an open one or 4 hole. I have read the info on the torque and hp benefits between the two, but if the stock gasket that was about 1/4" wood material was open, is there something that won't work correctly with a 4 hole? The stock intake is divided except for a 1/4" deep, 1" dia, opening between the sides, plus there is a 1/8" deep indentation in the front, between the primaries that leads to the primaries.

thanks,
phil

 

You'll probably want to use a 4-hole spacer to match your carb like this one from Brezinski
http://www.einfo-net.com/motorsports...s/spacers.html

 

A 4-hole spacer is designed for increasing torque.
A open hole spacer is designed for increasing horsepower and top-end.

Both spacers do not make a drastic difference to a modified engine, but since your stock you should notice an increase.

With an LG4 I personally would get a 4-hole as to maximize the torque from it, but if you have upgraded your exhaust, then I would consider the open hole, to make more HP and get a little more RPM.

 

youre a dumb****, so ya know.

modified engines dont see gains from plenum volume changes?

whatever dude, just be informed. more often than not, you will notice more on a modified motor than on a stock one, however

you tell him that if hes got exhaust he should get "the open one"

lol, i didnt know exhaust classified as looking for all out power,

how about this,

if the motor doesnt see the high side of 5500, four hole

if the motor has heads/cam intake/ exhaust, look into an open one. 6500 ish or more.


adam

 

How many people do you know have gone out and bought Performer RPMS and Vic Jr's and gone "gee I needmore this 25 buck spacer must be what I need????"

Find me 10 people that use a spacer when they have a good aftermarket base!!!

 

it is a useful tool in tuning your power curve, dumb****.

i know of quite a few people who do use them to increase plenum volume, but you wouldnt know about that, you probably have a 3/4 race cam in your ride, too.

the reason alot of people dont have them, 1. no hood clearance 2. dont think about the possibility of gains


say you could use the rpm capability of a super victor, but without the larger ports, because you have an excellent flowing head, well, an open spacer would get you close to that.

vice versa, if your car is lacking in the midrange, stick a 4 hole in it, and see if it helps, it might not, but it might.

it will also give your carburetor a better signal to meter from, and throttle response will improve, at the cost of high rpm horsepower.

 

You know onebadwagon, this is a board where people share information, and it is just downright rude to call people dumb**** because they dont necessarily think the way you do. None of us know everything and we can all learn from this board. Im sorry, I dont think its right for you to just jump at people like that.

I have an open spacer on my car, and it hurt the low end and throttle response a bit. Im not sure if Im keeping it on yet. It did help the high end, but I dont spend enough time over 5000 rpm to really make it worthwhile, but it did add noticeable power near redline, but it may seem like it added more because of the less low end and it feeling like more up top. Also, my throttle cable was just slightly to short to work correct with the spacer. I need to run a very stiff spring return setup to keep my throttle cable from pulling back the throttle.

 

wow, i feel like a dumbass because i actually read the whole thread.....wow thats a couple minutes of my life I will never be able to get back.

 

HAHAHAHAHA

Technical content:


I'd go with the four hole, but I'd make sure i had decent exhaust first.

 

Going back and looking at 305sbc's post, he has a pic and I think I"d experiment with removing the divider between the secondaries to make both secondary butterflies available to both sides of the motor at the mid to upper end of your rpm range.

I recall reading something about how divided plenums only allow 1/2 of the flow per side (dual plane intake), but if the dividing wall has a "window" it will allow the intake to get flow from both sides of the carb, keeping the throttle response and torque on the bottom end and aiding high rpm flow.

I think edelbrock makes a manifold such as this.

Anyway, it sounds reasonable to me.

 

fyi,

Tried a 1/2" 4-hole and a 1/2" Open-hole on stock lg4. I like the Open hole better. Didn't notice that much difference in the low end but it idles much smoother.

phil

 

Im willing to bet it idles smoother because of a slight pull on the throttle cable, so it idles slightly higher. Mine idled smooth as silk, because it was idling 1100 instead of 600 rpm with the 1 " spacer. Im sure a 1/2" would have a similar effect, just not as much. A stiffer spring cured mine. I just cant see how it would idle smoother, not flaming, just anyone know the explanation for something like that, Im curious.

 

Who knows?
Adding a spacer & gaskets could've fixed a vacuum leak maybe.

 

Also another thing to mention is a 4 hole spacer will help boost the signal to the carb. Which will help the carb pull fuel out better, partly the reason why a lot of people think that the carb must be too small and buy a bigger one only to find out it runs worse.

Also in the race demon carb book they say a 1 inch spacer will increase the max hp by 500 rpms I believe (might be wrong, but I know that fact is in the book somewhere).