1" Carb spacer

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Kendog 170

Kendog 170

Let the boy go !
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I looking at a 1" spacer for my 7576 Air Gap Intake. Should I use the open spacer or the divided spacer or does it much matter. Street driven only .
 
Even though I suggested the 4 hole spacer, experiment with both if you have them. That way you will know what your combination responds best with.
 
I recently threw a 1 inch spacer/adapter in between my performer rpm with a spread bore opening, and my Holley 4 barrel with square bore holes (duh) The adapter I used is open style and so far from what I can tell, it seems a little harder to start so I need to feather the throttle for about 30 seconds on cold starts and once warm the idle is a little rougher than before, but at speed it seems to respond better at any point above 25mph. I also have a 4 hole adapter that I will be trying in the coming weeks to see if I notice any difference.
I am not sure how "scientific" this is because I admit I am not the greatest of achieving the perfect tune and I am only using a butt dyno.
FYI, my carb still fits fine under the stock flat hood but my old circular 14"x3" pie pan air filter no longer fits due to it contacting the bracing under the hood, I knew this going in but I still think its worth mentioning
 
Kendog 170 said:
Guess that's the next question. Will the 7576 Air gap fit with Eddy carb on a 68 GTS 340 with or without a spacer . ?
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I know my Stealth, Quickfuel 650 SS with a small 5/16" Isolator and 1" drop base clears.

With out the spacer and drop base it put the air cleaner lid into the hood insulation. I have a nice Mopar logo and fins imprinted into the insulation now..

So you may want a drop base at least.

I bought this to remove the air cleaner stud and wing nut. It works trick!

Quik-Latch.Com Your Authorized Dealer For Quik-Latch Products
 
I was a super sucker when I bought one. I tried many different spacers. The best one I ever had on was called a gasket and heat shield.

New pics 394.jpg
 
mderoy340 said:
HVH 1" super sucker work best for me. I tried them all and optimized jetting each time.
340 10.3:1, Airgap deep port match, 750 proform dp, IMM Indy RHS X heads, 904 3200 tight converter, 4.10 Gear Vendor OD.
HVH Super Sucker Carburetor Spacers SS4150-1AL
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i used a 2" one of those on my anglia gasser, they smooth the flow nicely from the carb base into the inlet.
neil.
 
On my Indy headed 434 the Super Sucker was worth 13 hp. The surprising thing was that it equalized the afr's from side to side.
 
justinp61 said:
On my Indy headed 434 the Super Sucker was worth 13 hp. The surprising thing was that it equalized the afr's from side to side.
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I’ve read, heard and video seen this a number of times now. Even though, truly, it is a combo dependent and driving condition dependent issue (what it is your doing with your car....) this seems to be coming up more and more. The A/F ratio thing was always mentioned like you said.

Today I help a buddy out and picked up his 410 stroker which performed best with a 1 inch open.
 
Most dirt track guys like the super sucker.... but they don't drive on the street very much.
 
Whether spacers work or not, or which type, is entirely dependant on the combination . NO predictions can be made for anyone's specific combo, but generalizations can be made.
Engine masters did dyno testing, open and four hole one inch spacer on single plane and dual plane manifolds on the same engine. Some combo's worked, some didn't .
Generally, four hole worked best on a single plane, open worked best on a dual plane.
I have seen a $20 spacer make 15hp, I've seen $150 spacer do nothing .
Your best bet (IF you have room under the hood) is get a cheap open and a cheap four hole and try em. That's the only way you will know what your combo wants.
 
supersucker Style spacers seem to lend themselves throughout the RPM range. Open spacers I lend themselves to the upper RPM range at least that's been my experience. But I believe with the newer manifolds and all of the research that was put into them spacers may not produces much change but once again it's all individual application specific. But you're looking at around 10 horsepower change if all goes well. if Hood clearance is an issue at all I would definitely skip it.
 
I TRIED A 1" open spacer on my 426 stroker when it was on the dyno made no difference . but have seen it add HP on other engines , like it's been said try both types see which one works for you . never seen one that looses hp . good luck
 
LMAO! That’s true. If it did loose HP, then your plenum is to big for the combo. This is often not the case though.
It might be so h that monsterous Indy single plane on a mello combo.
:rofl:
 
if your motor likes a 1" open spacer with a dual plane intake but you have no hood clearance cut the divider in the intake down, 1/2" at first and round it off. you can creep up to the cut you like but remember it's hard to put back.
neil.
 
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Thanks for the reponses. I have a 1" open currently , I'll pick up a cheap square 4 hole to try as well. Now the question of clearance with stock air cleaner. Will it fit without the spacer ? Where can I but a lower air cleaner base ? I'll try and measure the clearence now and add the added height of the airgap and see what I come up with.
Thanks again all .
 
Kendog 170 said:
Thanks for the reponses. I have a 1" open currently , I'll pick up a cheap square 4 hole to try as well. Now the question of clearance with stock air cleaner. Will it fit without the spacer ? Where can I but a lower air cleaner base ? I'll try and measure the clearence now and add the added height of the airgap and see what I come up with.
Thanks again all .
Click to expand...

Allstar Air Cleaners & Accessories | Allstar Performance
 
A word of caution on drop base air cleaners.
I have a B&B drop base aircleaner with more than two inch drop, it has a really neat reverse-velocity stack lid that straightens out the flow into the carb. It did very well in engine masters'air cleaner test. It's sitting on my shelf in the garage.
Why? Because with the extreme drop, i could never make throttle linkage or fuel hookup work. And the base effectively blocks off flow, the air coming into the filter looks like it hits the wall of the drop base and stops. Therefore, with a three inch filter and two inch drop, only one inch of filter would be used. I could use a four inch filter, but that defeats the purpose of the two inch drop!
My suggestion is to look for a repop of the L88 drop base, also aparently used on some ram air pontiacs. It has an excellent reputation, and about an inch and a half drop, if i remember right, and good airflow. It can be identified by the raised area for the float adjustment on a cathedral bowl holley carb. Summit has one, about forty bucks, others as low as thirteen, but in this case (definately not my normal position! Lol) i think spending the extra bucks is a good idea.
 
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Still no one with a 67 -68 dart with a SB and Air Gap that can comment if it fits under the hood ?
 
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