plenum spacers

[Craven Moorhead]

Don't know how many of you have tuned with spacers but I decided to try and improve the bottom end in my set up so I went to a 1/2" 4 hole phenolic to stop some heat transfer from the intake to the carb and gain better distribution while increasing the base height. At least with my set up it worked pretty well, I gained 150 rpm at idle. I am running an Edelbrock dual plane on my 440. I know the single plane like the open type on the top end. Once I punch the hole in the hood I am going to try the 1" super sucker to see what that does. Anyone else doing any fine tuning with spacers?

 

[moper]

I don;t use them on dual planes myself. But I do use them to adjust plenum volume on some engines. Just making sure here... You did re-adjust the carb once you added the spacer, right? If you add height, the throttle cable may need to be adjusted as it effectively gets shorter.

 

[Craven Moorhead]

I adjusted the cable and idle.

 

[Craven Moorhead]

I added a sub-stack and a base gasket I guess now we will see if it sucks.

 

[68dodge]

By adding spacers, you can loose bottom end with the wrong spacers. You should use the spacers that have the divided wall to help keep the effect a dual plane intake. i have tried different space that were open like a single plane on a single plane intake, and it did help some on top end, lost a little on the bottom end. Also tried spacers on dual plane intake, went to the divided spacer and gain some top end, but did not loose any bottom end. That was just my test results. Depends on the motor.

 

[stroker_valiant]

I put a spacer on today, along with a new carb. I wish I wuld have done one thing at a time, so as to tell the improvements apart. I had an 800 Holley DP on my small block stroker, Eddy air gap dual plane intake. I switched to an HP series 780 DP, with a 1 inch four hole phenolic spacer. The motor is so much more responsive now, even though it is a hyd. flat tappet cam and I dont spin it that high, it feels alot stronger on the top end. Overall, big improvement.

 

[jefflock]

I run a 1" Super Sucker on my Air gap manifold. It is designed to work on a dual plane.

 

[Craven Moorhead]

I run a 1" Super Sucker on my Air gap manifold. It is designed to work on a dual plane.

What type of results did you recognize? It looks like they are the best of both worlds open and 4 hole.

 

[440outlawdart]

the 4 hole will give you more torque out of the hole,while the open is good for the top end

 

[Dustbuster]

the 4 hole will give you more torque out of the hole,while the open is good for the top end

Exactly right. And don't forget about the benefit of keeping the A/F charge denser as the spacer prevents heat transfer.

 

[crossram383]

I added a sub-stack and a base gasket I guess now we will see if it sucks.

You should do a post on those headers ???