• Mustang Forums
  • 1965 - 1973 Classic Mustangs -General/Talk-
  • Classic Mustang Specific Tech

I think its about time for this edelbog to go...

  • Thread starter Thread starter taylor4g63
  • Start date Start date Mar 9, 2004
  • 1
  • 2
Next
1 of 2 Next Last

taylor4g63

Founding Member
May 6, 2002
921
0
0
Asheboro, NC
Mar 9, 2004
#1
  • Mar 9, 2004
  • #1
alright guys im wanting a new carb. Im willing to go buy a nice tuning book and learn what im doing, but ima need a good carb to start with. First off i can't decide between a road demon, road demon jr, or a good classic holley, or possibly a street avenger. Im also not sure about hwat size to go with. Im thinking for the road demons a 525 would be alright since they are rated wet anyway so its really alil bit higher, but i don't really know. Engine specs are in my sig. Oh and i don't know if this would matter or not, but more than likely i will be adding a small shot of nitrous soon (less than 100hp), so the carb will need to be able to keep up with that. Thanks guys for any help and input u can give.
 

allcarfan

The Answer Man
Founding Member
Apr 8, 2001
2,458
1
56
North Atlanta
Mar 9, 2004
#2
  • Mar 9, 2004
  • #2
Id suggest a small speed demon carb!!!
 

KillerKittyCat

New Member
Aug 24, 2003
150
0
0
Hammer Down - Behind The Wheel
Mar 9, 2004
#3
  • Mar 9, 2004
  • #3
Why the Demon?????
I have a Road Demon 625 that will not work on the 289. Barry Grant wants the carb back so they can "look" at it Resized the jets, did this did that.
Go with the avegner.
 
U

UNVMATT

New Member
Jan 15, 2004
294
0
0
COLUMBUS
Mar 9, 2004
#4
  • Mar 9, 2004
  • #4
I second the Avenger!
It worked wonders for my Cleveland!
 

rbohm

Founding Member
Apr 12, 2002
6,698
550
204
tucson,az
Mar 9, 2004
#5
  • Mar 9, 2004
  • #5
i just put a 600cfm edelbrock(didnt want to wait for a 500 cfm one) on my grand marquis(stock 302) and it runs better now than the cfi system ever has. describe your problem, it would be willing to bet that it is running a bit lean judging your engine combo.
 

66 BLAKE 96

Native Texican
Founding Member
Feb 16, 2001
4,810
0
0
Cowtown
Mar 9, 2004
#6
  • Mar 9, 2004
  • #6
My Edel has never bogged or had any other problems. I believe the carb experts when they say a Holley or Demon can't be beat for a race car, but for the street I wouldn't trade my Edel for anything. (Well, maybe for EFI)
 

taylor4g63

Founding Member
May 6, 2002
921
0
0
Asheboro, NC
Mar 9, 2004
#7
  • Mar 9, 2004
  • #7
well i've always heard that a holley will make more power given the proper tune. I've also heard only good things about demon carbs. When i first built the engine, i didn't want to have to mess with tuning a carb and just wanted to throw it on there and go, but now i've got most everything worked out, got a bit of free time and im wanting to tinker a lil bit. What size carb should i go with? i believe the avenger comes in 570 and 670 sizes, should i go with the 670 and jet it down? Same thing with the demon, which size would be better?
 
G

GaPonyFarm

New Member
Jan 2, 2004
663
0
0
Columbus, GA
Mar 10, 2004
#8
  • Mar 10, 2004
  • #8
I'm sold on the Street Avenger - 670cfm. I have it sitting on an Air Gap RPM and the '66 runs like a scalded dog... Similar internals to what you're running.
 

Jonstantine

Founding Member
Jul 20, 2002
487
0
0
Oklahoma
Mar 10, 2004
#9
  • Mar 10, 2004
  • #9
edelbrocks dont have vacuum secondaries buddy;
thats probably why you have a bog...

of course its the edelbrocks fault that you bought the wrong size
 
1

10secgoal

Active Member
Dec 1, 2003
2,801
3
49
San Diego
Mar 10, 2004
#10
  • Mar 10, 2004
  • #10
Edelbrocks bog because they aren't a true vacuum sec. And they don't have a secondary pump shot. You can get around that at the track by making it have a huge pump shot to over compensate. You can't throw on a carb that's too big and jet it down. The CFM is what's too big. That you can't really down jet that (You can but it tends to be expensive). I have always loved my edelbrock till I tried a holley. I will never go back, ever....stock motor or full race. You can even get better gas mileage out of a holley/demon than an edelbrock. They are a little harder to tune though. But well worth it.
 
S

Sicarius428

Active Member
Jan 6, 2004
2,085
5
49
Mar 10, 2004
#11
  • Mar 10, 2004
  • #11
I say steet avenger. I am really pleased with mine. Here is the formula for choosing the right size
Engine size (CID) x maximum RPM / 3456 = CFM
CFM @ 100% volumetric efficiency

(Example: 350 CID x 6000 RPM = 2,100,000 / 3456 = 608 CFM)

Usually on the 302s i see the 670 although technically the 570 by the numbers would be perfect. 670 will give you more room to grow and Fords like them a little bigger anyways.
Kevin
 

taylor4g63

Founding Member
May 6, 2002
921
0
0
Asheboro, NC
Mar 10, 2004
#12
  • Mar 10, 2004
  • #12
thanks guys for all this info. Im a complete newb to carbs if you haven't noticed.... Didn't know the edelbrock didn't have vac. secondaries.

So now im about sold on a street avenger, probably 670 but maybe the 570. I still have the road demon 625 in the back of my head though, anybody else tried one of those?
 

taylor4g63

Founding Member
May 6, 2002
921
0
0
Asheboro, NC
Mar 10, 2004
#13
  • Mar 10, 2004
  • #13
oh one more thing, can somebody suggest a GOOD holley tuning book? i about bouught a haynes one tonight, but i'd much rather spend my money on a good one...
 

Jonstantine

Founding Member
Jul 20, 2002
487
0
0
Oklahoma
Mar 11, 2004
#14
  • Mar 11, 2004
  • #14
taylor4g63 said:
thanks guys for all this info. Im a complete newb to carbs if you haven't noticed.... Didn't know the edelbrock didn't have vac. secondaries.

So now im about sold on a street avenger, probably 670 but maybe the 570. I still have the road demon 625 in the back of my head though, anybody else tried one of those?
Click to expand...
i made the same mistake; matter of fact i was talking to their help people and i mentioned vac secondaries, and the guy was like...
"they dont have vac secondaries"
he must have been thinking, "what a moron"

i lowered my floats and bought a high flow needle and seats and have had zero problems with my edelbrock since

the next performance rebuild i do will probably have a road demon on it... not that i have any experience with them
 

taylor4g63

Founding Member
May 6, 2002
921
0
0
Asheboro, NC
Mar 14, 2004
#15
  • Mar 14, 2004
  • #15
so can anybody recommend a good book for tuning on holleys???

Pretty sure im gonna go with the street avenger, will the 670 be alright?? Im not too concerned with Gas milage as i have a honda for a DD, but will it run good with the 670 or will it be a dog...?
 

67GTCOUPE

Founding Member
Dec 20, 2000
653
0
0
Land of Ice and Snow
Mar 15, 2004
#16
  • Mar 15, 2004
  • #16
Edelbrocks are VERY PRESSURE SENSITIVE! Meaning: max 6psi inlet pressure, or you will have problems!

I got rid of my edelbrock, and 750 Holley DP and I bought a QUICK FUEL PRO VAC 750...............AWESOME!!!!!!!! It is the best thing I have ever done....it responds like EFI!

I strongly suggest you look at a Quick Fuel Pro Vac 650 carb.

www.quickfueltechnology.com


EDIT: If you go to their web...the 650 is under "monthly special".
 

ratio411

Founding Member
Apr 21, 2002
3,870
73
109
Pensacola FL
Mar 17, 2004
#17
  • Mar 17, 2004
  • #17
I think you are shooting too low on the carb size.
You mention a 670, don't go any lower.
You have a very healthy set-up there by your sig.
Some things to keep in mind:
The formula for carb size is just a guideline too keep people out of trouble, it is not set in stone and usually a larger carb works better if properly tuned.

A dual plane intake tames cfm. A DP will make a carb act smaller than it is. Conversely, a SP will overcarburate easily.

A vacuum secondary carb, even when too large, is not breaking the rules by the carb size formula because the engine only takes as much secondary cfm as it can use. A 750 Holley vacuum only has as much carburation as a stock 2 barrel carb on the primary side, then you tune in the extra you need on the secondary side.

Get your new carb first, but when you get a chance, I highly recommend trying a very mild single plane with your combo. I would bet money that you would like it better with your set-up.
Spend a few hours installing a used (inexpensive) Wieand X-cellerater, Offy Port-O-Sonic, Holley Strip Dominator, or Edelbrock Torker 289 (not Torker 2!!!).
I had a very similar set-up to yours with a Torker 289, 218 @ .050 cam, Holley 750 Double pump, stock converter, and 4.11 gears... the car was a screamer! I tried the Performer RPM because I fell for the "Dual planes are better for the street" rule... the car fell on it's face.
Good luck
Dave
 

taylor4g63

Founding Member
May 6, 2002
921
0
0
Asheboro, NC
Mar 17, 2004
#18
  • Mar 17, 2004
  • #18
thanks dave for the info. Do you have any suggestions for a good book on tuning a holley?
 
G

GaPonyFarm

New Member
Jan 2, 2004
663
0
0
Columbus, GA
Mar 17, 2004
#19
  • Mar 17, 2004
  • #19
taylor4g63 said:
so can anybody recommend a good book for tuning on holleys???

Pretty sure im gonna go with the street avenger, will the 670 be alright?? Im not too concerned with Gas milage as i have a honda for a DD, but will it run good with the 670 or will it be a dog...?
Click to expand...

There are several books about carbs in general, and some on Holley specific. You might want to do a search on Amazon and read the synopsis for each book, then decide what's right for you.

The Street Avenger is not going to be difficult to tune. It comes with pretty good instructions and I'll bet you $2.00 that you won't have to make any adjustments, right from the box.. Of the 10 or so, I've put people's cars, only one needed any substantial adjustments. There is one downside to the Street Avenger, in my opinion. I hate the glass sights and would recommend changinging to brass plugs, once you know the fuel level is correct.
 

ratio411

Founding Member
Apr 21, 2002
3,870
73
109
Pensacola FL
Mar 17, 2004
#20
  • Mar 17, 2004
  • #20
Hate the glass sights?

I love them. No mess and you always know things are right with a glance.

Just my opinion. To each his own.
Just curious, why don't you like bowl sights?
Dave
 
  • 1
  • 2
Next
1 of 2 Next Last
You must log in or register to reply here.

Similar threads

Place to Avoid: Jamison Auto Group in Gulfport, MS
  • D Durden
  • Oct 20, 2025
  • 1965 - 1973 Classic Mustangs -General/Talk-
  • 2 3
Replies
46
Views
3K
1965 - 1973 Classic Mustangs -General/Talk- Jul 16, 2026
Noobz347
Which one of these 3 intakes make the most sense for my 331 combo
  • from6to8
  • Jul 25, 2024
  • 1994 - 1995 Specific Tech
Replies
7
Views
2K
1994 - 1995 Specific Tech Jul 26, 2024
AeroCoupe
C
New here. Was left a 67' Mustang 347. Ready to go down the rabbit hole but don't know where to start.
  • cmille198
  • Jun 29, 2023
  • 1965 - 1973 Classic Mustangs -General/Talk-
Replies
4
Views
2K
1965 - 1973 Classic Mustangs -General/Talk- Jul 12, 2023
AeroCoupe
Took some pics, i do really own a mustang...
  • 2000xp8
  • Jun 20, 2023
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • 6 7 8
Replies
148
Views
19K
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Oct 1, 2024
Mustang5L5
S
Mustang 200 EFI Conversion
  • Scuderia
  • Nov 16, 2021
  • 1965 - 1973 Classic Mustangs -General/Talk-
  • 2
Replies
22
Views
9K
1965 - 1973 Classic Mustangs -General/Talk- Aug 23, 2024
Scuderia
S
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1965 - 1973 Classic Mustangs -General/Talk-
  • Classic Mustang Specific Tech
Menu
Log in

Register

  • Forums
  • What's new
  • Media
  • Resources
  • Contact
  • Sponsor
X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?

X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?