Calling Mad P, Dr. Dan and any other expert

[Budmann]

I
I have a 350 LT1 putting out around 400 HP. I need suggustions on what Carb. to buy.
I have an Edelbrock on there right now and it is "A PIECE OF ****!!!!"

Help!!!!!!!!!!!!

[turbo2256]

I
I have a 350 LT1 putting out around 400 HP. I need suggustions on what Carb. to buy.
I have an Edelbrock on there right now and it is "A PIECE OF ****!!!!"

Help!!!!!!!!!!!!

Whats your max RPM, intake your using ? application car boat truck?

[Budmann]

Sorry... 22 Donzi. Max rpm is 5200. Performer high rise intake.

[Lenny]

...my Edelbrock needs rebuilding as well and I'd prefer a new one to be honest. 350 as well, Performer as well, 5200RPM as well so I WILL be watching this answer closely :D

[turbo2256]

Best to list anything else you have done to your engines.
A 600 holley double pump would be my choice with no other info a 585 BG should even do better if there is a marine version.

[Eugene Nahemow]

I am not an expert on carbs but I did buy my from one.
I worked with Ty at TPC to build my carbs.
He did a great job. Just give him your engine specs and have him build one for you. I also thought his cost were reasonable compared to others I talked to.
Here's a link for anyone interested.
http://www.tpcracing.com/tpc_carburetor.html

[Budmann]

I have had it rebuilt 7 times because I thought it was just being done wrong. Then I spoke with the local hi-rpo person locally and he told me that they (Edelbrock) makes good intakes but their carbs. suck.

I agree!!

[Lenny]

I found this on the net under BLP products (NASCAR carb builder)


How To Calculate CFM: Engine size (CID) x maximum RPM / 3456 = CFM
CFM @ 100% volumetric efficiency

Most Street engines are capable of achieving only about 80% VE; a modified street engine with ported heads, headers, intake and carburetor can achieve about 85% VE; a fully modified race engine can achieve 95% or greater VE. The CFM number arrived at with this formula must be factored by this percentage.

Don't know if it is relevant mind you.

Makes a 600CFM more than adequate

[BRIAN73]

Hi,

650 Double Pumper with a rejet.

Just my oppion


Brian
Owner of smallblocks

[Budmann]

C'mon guys... I want to get a holley! Does anyone have any expierence with them. A 650 Double pumper is what was suggusted.

Isn't that to much juice??

[Lenny]

Is this the one you mean Poodle?

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=763&item=6947661126&rd=1&ssPageName=WD1V

[BigGrizzly]

Bud I have had great luck with Hollys and the BG sea deamon. The Criterion has a 825 on it and it is great as you know The Corsican uses a 600 Holley. and has not given me any greif for 14 years. Yes I do use as well as the Criterion but only about 30 hours a year. I f your carb has been rebuilt 7 times then not only a new one is needed but a different type-(brand) I have done alot of engines in my day and the truth is that some combinations like Holys and hate the eldbrock/carter. and some like only the Eldbrock. If your motor is a 350 and not a 383 a 600/650 cfm is all that is needed. In fact it will give the same power or mor and better fuel economy than a 700/750CFM carb. So go get a NEW one and be done with it. I would

[Lenny]

"If" a guy was to buy a Sea Demon, say a 650 or whatever, would he want vacuum secondarys or mechanical?

I have the Performer as well. What should I expect to pay for one?

What about re-jet? I know NOTHING about motors, and to get it "jetted" here would be a disaster waiting to happen. Should I say, "sea level", 30 over 350, running 5200? HEI ignition?

:confused:

[BUIZILLA]

Get a SeaDemon 650 vacuum secondary, put it on out of the box, adjust the idle mixture, and leave it alone.

JH

[Rootsy]

vacuum for economy and you can tune em when to open...

go to summitracing and do a search on BG seademon... they MAY have em in stock... they did a year ago... you just had to search for em...

i own a demon and i like it A LOT better than any holley i've ever owned... gee wiz now holley is offering billet parts for their carbs as add on pieces, etc.. the demon ALREADY comes with all of the bells and whistles... even BEFORE it is put into marine form...

[Lenny]

Sorry for "hijacking" Mr. Staples thread. I got GREAT info. Thanx again. Back to the regular scheduled program ;)

Sorry Bud. :)

[jg480]

Lenny, JEG'S lists the marine Demon 650 with mechanical secondary for $561.99.They also list a marine version Holley 600 vacuum secondary for $366.99. You may also want to check Summit Racing's catalog.

[fasttrucker]

I had to replace my fuel line to a larger dia....for my holley double-pumper.Had it now for two seasons,no problems!...Victor JR. manfold on my 502 big block.

[Budmann]

Mp... yes it is. I have a "very" dependable quadrajet that now doesn't fit. :splat:
Lenny.. Always a pleasure reading your replys. you can jump on my thread anytime! (in a non-gay way ofcourse) hehe :biggrin.: :biggrin.:

To the rest of you... THANK YOU SOOOOO MUCH!!!!!!!! I think I'm going to buy a bg. Pretty pricey but want to bolt it on and forget about it.
As long as we're on the subject.... if I was to change out the Performer intake would anyone like to suggust what would be a good match based on the info I have provided. :confused: :confused: :confused:

[Budmann]

Yea MP it seems to work fine I just hate the wide bolt pattern. I think someone makes a adapter plate so I could go back to a regular spread on the carb.

[joseph m. hahnl]

C'mon guys... I want to get a holley! Does anyone have any expierence with them. A 650 Double pumper is what was suggusted.

Isn't that to much juice??
I"ve had a holly before and it worked well the only problem i had was in the idle circuit it would surge. so i did some research on it . it turned out to be the power valve. i ended up measuring the vacume in the manifold as i was diving in the idle circuit. at a certain drop of vacume especially with a high lift cam because they reduce vacume in the manifold. the vacume was dropping more than what the the power valve i had in it closed at 14 and the vacume average was 10. so it formed this visious cycle of opening and closing. once i put the correct power valve in it ran as smooth as a velvet. i would suspect they still use power valves in the holley's because carburator design has not changed and actually has been replaced with fuel injection and direct injection.
on all most all new engines with any substantial displacment. due to the drive for better fuel efficiency and gas emissions. but that has no bearing on the need for speed ,or in a race who cares about how much fuel you use or if your depleating the ozone. as long as you left the other guy in your wake. but i have heard that the holley dominator or predator which is not a convetional carb. is an excellent choice i'm not sore but i think it's the predator that uses way fewer valves then the traditional carb and comes in either a spread bore and inline and it requires less maintainence it would allso eliminate the need for an adaptor plate, the adaptor plate would add more rise to your allready high rise manifold. and becuase it comes in both would also eliminate the need for a new manifold. hope that gives you some more choices. i think you should really look in to a predator.

[TREYSTJOHN]

With your app. I would recomend either the marine Holley or the Sea Demon 650's mech secondary (Jegs.com usually has both, there is also a guy on ebay who sells the Demons with fuel line for same price as Jegs carb only). Start boat and check/adjust float levels. Take out boat to warm up , set idle to 800-900rpm out of gear, put in gear and adjust your idle circuit screws until you get max vacum at manifold which should also be max rpm in gear, back screws out 1/4 turns. At this time note vacum reading, power valve should be chosen to be 1/2 this reading (ie if vacum is 11 install a 5.5 power valve). Most the 650's come with 6.5pv and depending on your cam should be in the ball park. With your manifold do not use any carb spacers or 1/2 inch at most otherwise you will end up with 2 or 3 cylinders that will run lean (usually 4,6). Run boat at 500rpm increments/shut down and check plugs 1 and 4 for basic verification of burn heat.
As a side note, 400HP at 5,200 rpm sounds a bit aggressive, most pump gas marine 350's that we have built need to turn at least 5,800rpm to approach 400hp. If you tell me what cam, heads and exhaust you are running we may be able to help you squeak out some more power.

Have fun, Trey

[BUIZILLA]

Trey, tell me more about this guy on eBay with the Demons for sale... I need one too, but I need an 750-850.

JH

[Lenny]

:rolleyes: Treystjohn...This is the part I was "waiting" for...

The only Vacuum I know of is in the closet, and it doesn't get out much :D and as for "Lean" well I did that last night against a wall in order to impress some Girls and still stay upright.

I knew it was only a matter of time till this went waaaayyy over my head :D

Thanx tho. I printed it on hard copy in case Albert Einstein decides to drop by for a beer...

Back to cabinets, something I know about. :)

...seriously tho, I printed it and will find someone, somewhere here, that can do this for me. THANX

[TREYSTJOHN]

JH

Here is link to one of the carbs this guy sells, he has lots of Demons for sale. Call him up and tell him what you need, his price for new Demons is the same as Jegs, and he includes the fuel line kit.

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&item=7959865827&category=33550&sspagename=WDVW

Trey

[Lenny]

Back to making boxes... I'll check back when you (who understand this stuff) have it figured out... Let's see. May 20th, Kentucky. I think it is doable. :)

[Lenny]

Poodle, when I get mine, I'll mail you my feet (requested) :D The aluminum ones, not mine. Regardless, you still could never catch me :D

Blue or Red Poodle, I am assuming Blue. ;)

[SWEET 66]

Lenny, I thought you were a glass man. Anyway, you get credit for the patients displayed while replying to the 16' hatch cover I recently read. Just had to say something on your behalf!

[Sea Biscuit]

I'd call Marv Benoit at Quick Fuel (ex Holley Performance guy).His company number is 270-793-0900. He's probably the best carb builder around, lots of trick componants etc

[Rootsy]

You can use a standard fuel line setup for a dual feed that has female -6 fittings on the ends.. you'll need 2 of the 7/8 male to -6 AN male adapter fittings though. Easily aquired at summit or jegs or wherever... generally listed for the BG application... had to do this on my 750 when i switched from the holley... have to make sure you get a fuel line with a spread for a true 4 jet holley though... otherwise you'll be a bit short...

with a boat.. the vacuum (load) curve is a bit different than in your car.. you not only have to tune the vac secondaries opening point but also the powervalve generally, especially on modified motors... a boats vacuum curve is almost linear once you are on plane until WOT... literally... i idle @ 11 inches of Hg, on plane around 2500 i am about the same... WOT @ 5500 it is ZERO... plot it out and draw a straight line... i've noted readings every 500 rpm... important info to have when tuning your power and secondary circuits for economy...