Team Camaro Tech banner

1 - 20 of 20 Posts

·
Registered
Joined
·
384 Posts
Discussion Starter #1
On my 383 I have an Edelbrock RPM Air gap intake. There is a threaded port that I wanted to run my power brake booster, but my carb is in the way. (Holley 750hp) SO, I have my brake booster connected to the carb base plate- where is where I want to hook the valve cover PCV line. Any suggestions on how to route/re-route to get both?
 

·
Moderator
Joined
·
14,099 Posts
On my 383 I have an Edelbrock RPM Air gap intake. There is a threaded port that I wanted to run my power brake booster, but my carb is in the way. (Holley 750hp) SO, I have my brake booster connected to the carb base plate- where is where I want to hook the valve cover PCV line. Any suggestions on how to route/re-route to get both?
Put a "T" in the line that come off the base plate
 

·
Premium Member
Joined
·
11,167 Posts
I have heard this before about the carb being in the way. Vac port is directly under the rear carb bowl. I run the factory vacumn multiport on my air gap , using a short brass street ell into the port you are talking about. It allows that multiport connection to mount horizontally , using the inverted flare nipple for booster vacumn and headlamp doors.
The vacumn port behind the carb base is what I use for the pcv .
 

·
Moderator
Joined
·
14,099 Posts
I have read a few articles warning against this for reasons of oil contamination entering the brake booster this way.
With a properly operating pcv valve you will not get any contamination.
 

·
Registered
Joined
·
8,349 Posts
Edelbrock makes low profile fitting for this. Use it along with a 1/8" NPT nipple. There shouldn't be an issue with this but if have one and have the hood space you can use a carb spacer to correct it.
http://www.summitracing.com/parts/edl-8096/overview/
http://www.summitracing.com/search/brand/gardner-westcott-company/product-line/gardner-westcott-hose-barb-to-pipe-fittings/fitting-size-1/1-8-in-npt/fitting-size-2/3-8-in?N=400302+317545+4294947333+4294926874&SortBy=BestKeywordMatch&SortOrder=Ascending

If you want to run a T and have any concerns, you can use a C3 Corvette brake booster charcoal filter made just for keeping gases out of the booster. I use one myself since due to my setup I have to run PCV, booster, cruise control, and vac advance all off one port. Most parts stores carry them in stock.
http://www.autozone.com/autozone/parts/Brake-Power-Booster-Filter/_/N-8kp7e

Info on filter:
http://www.corvetteforum.com/forums/c3-tech-performance/1950912-power-brake-booster-filter.html
 

·
Premium Member
Joined
·
11,167 Posts
Edelbrock makes low profile fitting for this. Use it along with a 1/8" NPT nipple. There shouldn't be an issue with this but if have one and have the hood space you can use a carb spacer to correct it.
http://www.summitracing.com/parts/edl-8096/overview/
http://www.summitracing.com/search/brand/gardner-westcott-company/product-line/gardner-westcott-hose-barb-to-pipe-fittings/fitting-size-1/1-8-in-npt/fitting-size-2/3-8-in?N=400302+317545+4294947333+4294926874&SortBy=BestKeywordMatch&SortOrder=Ascending

If you want to run a T and have any concerns, you can use a C3 Corvette brake booster charcoal filter made just for keeping gases out of the booster. I use one myself since due to my setup I have to run PCV, booster, cruise control, and vac advance all off one port. Most parts stores carry them in stock.
http://www.autozone.com/autozone/parts/Brake-Power-Booster-Filter/_/N-8kp7e

Info on filter:
http://www.corvetteforum.com/forums/c3-tech-performance/1950912-power-brake-booster-filter.html
Steiner, Thanks for the tip on the booster filter, makes sense. As for the Summit brass ell, that's the style I found but mine was 3/8 x 3/8".
Thanks for the tip.
 

·
Registered
Joined
·
8,349 Posts
Side note to above....

What model Holley is it? Does it not have another 3/8 port under the front edge? 750 Street HP pic:

 

·
Registered
Joined
·
8,349 Posts
You bet, Don.
 

·
Premium Member
Joined
·
11,167 Posts
Side note to above....

What model Holley is it? Does it not have another 3/8 port under the front edge? 750 Street HP pic:

Looks like the base of my 3310-4 , could look like a 4780 , I use that back base port for the pcv hose. Don't use front ports as I have a mechanical advance. thanks M8
 

·
Registered
Joined
·
8,349 Posts
Yeah, that was meant to be right under my other post and directed at Marc but you slipped in there while I was typing it up so it looked like I was asking you. :beers:

Actually, I tried to put it in my original post but was once again bitten by the edit timer.
 

·
Premium Member
Joined
·
11,167 Posts
Yeah, that was meant to be right under my other post and directed at Marc but you slipped in there while I was typing it up so it looked like I was asking you. :beers:

Actually, I tried to put it in my original post but was once again bitten by the edit timer.
My apology to you and Marc.
 

·
Registered
Joined
·
8,349 Posts
What? Why? No apologies needed man.
 

·
Premium Member
Joined
·
11,167 Posts
What? Why? No apologies needed man.
Steiner, while I got you on the line. I have a 850 HP and it runs well , better than my 3310 but does not have the crispness of response of the 3310.

Since you brought up the base picture of the 750 HP, Do you think I would notice any response or difference if I went to the 750HP?
I would set the hp up with same jetting, pv , etc as the 3310. The only differences I see are the downleg boosters.
Even thinking a bout what may be coming to us in line of E85.
Opps, I may have run into a snag here, these HP carbs don't have electric chokes.
Opinion?
Anyone else?
 

·
Registered
Joined
·
8,349 Posts
Don, I'm probably the last person to ask. All I could say is that when you went from the 3310 to the 850, you surely took a hit in air velocity at low speeds which you'd definitely feel in the response department. Velocity isn't just getting air into the engine but also what causes the pressure drop to get the main circuit flowing fuel instead of relying so much on a pump shot to get going. I don't know what kind of power that bad little thing makes, but consider that my 400 only needed a 780 to feed 500hp on the dyno of course it peaked lower than yours does.
 

·
Premium Member
Joined
·
11,167 Posts
Don, I'm probably the last person to ask. All I could say is that when you went from the 3310 to the 850, you surely took a hit in air velocity at low speeds which you'd definitely feel in the response department. Velocity isn't just getting air into the engine but also what causes the pressure drop to get the main circuit flowing fuel instead of relying so much on a pump shot to get going. I don't know what kind of power that bad little thing makes, but consider that my 400 only needed a 780 to feed 500hp on the dyno of course it peaked lower than yours does.
You are correct in air velocity as I tested the 3310 with a vacumn gauge at wot pulling , the gauge never got below 2" with this motor, but stayed there til I ran out of road, which told me I was good with this carb.
If I recall the testing goes something like, if your eng vac goes below 1.5" or so, you need a larger carb with same engine.
Carb cfm calculator says, I need 650 so 750 is some margin. I was just looking to see what response would be gained with down leg boosters, read somewhere drivablity is said to be better at low speeds with straight leg, down leg better higher engine speeds. So I guess I am in the middle. Chassis dyno pegged me at 375 hp at 6138 with tq about at 360 or so with 373 gear.
Thanks anyway. will keep checking but I bet I stay where I am, if it aint broke, you know the rest.
 

·
Registered
Joined
·
8,349 Posts

·
Premium Member
Joined
·
11,167 Posts
Check this out.
http://www.popularhotrodding.com/tech/0511phr_carburetor_boosters_tech/
I kinda went glassy eyed reading it but what I got from it is that the booster design is a big part of getting a big carb to deliver similar low speed performance of a small carb while maximizing power potential.
Good read. Looks like I will keep my 80531HP Holley. It has potential. But I do know that it does cause a little mpg loss . I did tune it with my LM1 and its almost jetted the same at the 3310.
Thank you for the article. I am sure others will read.
 

·
Premium Member
Joined
·
1,417 Posts
I had the same issues with my 650dp. I used the Edelbrock low profile fitting on my rpm manifold and I still needed to use a 1/4 inch spacer to clear the fitting.
 
1 - 20 of 20 Posts
Top