chris83z28

Here is the break down,

about 55 degrees, elevation 3300ft

Edlebrock- (600cfm square bore, vac. advance dist- 11 degrees initial timing)
16.49s at 83.9mph
16.46s at 84.5mph
16.27s at 88.6mph

Quadrajet- (computer controlled, same dist, no change in timing)
15.48s at 95.2mph
15.42s at 94.7mph
15.32s at 98.6mph

The only change in the test was the carb. Yes, these computer controlled qjet times are with a rigged vac. advance dist. Does any one see a trend here? I am convinced that the Edelbrock carb is a waste of money. Don't get me wrong, I love other Edelbrock products. The engineers just need to go back on the drawing board on there square bore carb.


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1983 Camaro Z28
Goodwrench 350ci V8, Edelbrock TES Headers, Flowmaster Catback, MSD 6al and Blaster 2 coil, Edelbrock Performer intake, (Edelbrock Performer 600cfm carb.)- went back to q-jet!!! T5, 373 rear, Eibach springs, Cervin Vega speakers, Rock. Fos. Sub, Pioneer CD,
email-chris4421@hotmail.com
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"I used to be a Mustang Guy! I didn't know the power of the dark side!!"

Jester

I've been saying for a long time that Edelcrocks products SUCK!! Especially thier carbs. I flat out refuse to use anything of thiers on my car.

Nonetheless..even I am a bit surprised at that large of a loss. I'd think even a 600 Edelcrock could break even, maybe even offer a gain over a CCC Q jet..but i guess not. I'd say that it needs tuning..but Edelcraps biggest point in the plus column is that it can be run effectivly right out of the box..unlike a Holley.

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"American made baby. 100% American iron. The muscle among the masses. My hero. Yep, you can take your ergonomically designed, space age, computer controlled, 4 door, cup holding map lighted split double wishbone split fold down retractable cargo covered moon roof piece of transportation and keep it. For I have felt the thunder. And I know the difference!"
JSP Motorsports
ICON Motorsports

[This message has been edited by Jester (edited March 11, 2001).]

AlkyIROC

I'd say tuning also.

The Edelbrock design has been around for a very long time. It's based on the old Carter AFB carbs from the 60's. Edelbrock just changed some stuff and made it shiney. I never liked AFB carbs myself.

Throw the Edelbrock back on and start increasing the jets. Being down 10 mph is a big drop in HP but the carb hasn't been tuned to the engine yet. That's like dropping in a distrubutor and not setting the timing or having it recurved. It will run but not as good as it could.

The best way to tune an AFB is to put in the largest jet available then adjust it by changing the rods. Keep increasing the size until the MPH stops going up then go back to the last size.

There's also nothing wrong with a Q-jet. When you look at a Stock Eliminator car running 10's or 11's with a Q-jet and cast iron intake you know it's tunable.

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Follow my racing progress on Stephen's racing page
and check out the race car

87 IROC-Z Pro ET Bracket Race Car
383 stroker (carbed) with double hump cast iron heads and pump gas
461 Big Block installed and ready for the 2001 racing season

Best results before the 383 blew up
Best ET on a time slip: 11.857 altitude corrected to 11.163
Best MPH on a time slip: 117.87 altitude corrected to 126.10
Altitude corrected rear wheel HP based on power to weight ratio: 476.5
Best 60 foot: 1.662

Racing at 3500 feet elevation but most race days it's over 5000 feet density altitude!
Member of the Calgary Drag Racing Association

87 IROC bracket car, 91 454SS daily driver, 95 Homebuilt Harley

84TransAm

That's why I love my Holley!

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--Steve S--
1984 Trans Am 305 LG4, 5 speed
Daily Driver, Flowmaster 80 Series
NOW FEATURING: Holley 600 cfm & vacuum advance

Jester

Altho when I look at his sig closer...the Edelcrap should NOT be that far off. That is a very mild, middle of the road engine. Tuning should not be able to explain a full second loss in this situation...MAYBE a couple tenths.

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"American made baby. 100% American iron. The muscle among the masses. My hero. Yep, you can take your ergonomically designed, space age, computer controlled, 4 door, cup holding map lighted split double wishbone split fold down retractable cargo covered moon roof piece of transportation and keep it. For I have felt the thunder. And I know the difference!"
JSP Motorsports
ICON Motorsports

AlkyIROC

True. Maybe a vaccum line was left off and it was running lean? Maybe the base plate gasket didn't seal? Anything could have been the problem.

I'm curious about having the spread bore q-jet and the squarebore AFB. The manifold should be a dual bolt pattern but were the proper gaskets used?

I don't even like Holleys any more. I run a Demon now.

84FTA

I would like to know more about this carb, it's history and tuning. I suspect something array with the readings. A full second is way off.

Jester, I believe that 'tuning' as we know it isn't the cause. We usually refer to that as fine tuning. However, if it is slapped on out of the box or even worse a crappy rebuilt one that hasn't been "rough" tuned then 1 second isn't terribly off.

I would of liked to see some additonal test results using the CCC with the stock distrib (assuming it was an L69 or later LG4 model with knock sensor) just to see how those performed compared.

This is the basis for my CCC project. I see some potential for design that was held back in the early days by lack of technology and held back later on by emissions (when they had to switch to TBI) and the CCC didn't get a full exploitation of it's capabilities.

Anyone else in this post whom is still running a CCC on a (heavily) modified 305 or a mild higher cube engine. I've heard a rumor of once you get up there in breathing capacity that the accel pump proves itself as an ineffective flaw, anyone else expierence this?



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1984 WS6 Trans Am Hartop
Former L69 Car under restoration
1984 Trans Am T-tops
4-bolt main 350, performer intake, headers, Holley 650, T-5, hayes clutch, dual elec. fans and 3.23's.
Daily driver and restoration
13.98 @ 101

FlashGTA

Even if the tuning is off, the Edelbrock is just a Carter AFB. No one liked them when they were made by Carter because they were junk. The name has changed but nothing else. HOLLEY's RULE!

Pablo

iTrader: (1)

you didnt even bother changing jets, metering rods, etc.. thats not a good comparison at all

parts are in my opinion 50% of the battle or less, the rest is tuning. You give either of those carbs to experienced tuners and the car would run probably a few tenths faster than your best time now, and probably very close to another

taliesian

a 600 cfm carb vs a 730 cfm? wonder why the q-jet won, run with an edelbrock 750 and get a result with more equality. I am not "standing up" for their carb, but a 130 cfm advantage must count for something? My friend took his q-jet off and put a holly 600 or 650 dp on and lost power throughout rpm range and ended up with a motor that was dead over 5000 rpm when it had the q-jet it pulled strong up 7000 rpm

Pablo

iTrader: (1)

his car runs mid 15s, it doesnt need air, it needs tuning. You cant just slap a carb or fuel injection system on any motor and expect it to automatically know what to do and when, it needs to be tuned. 600 cfm is plenty for his engine

super83Z

I bought an Edelbrock cuz they were cheap from Autozone. when i save up some cash i am going to a demon too.

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LONG LIVE THE MUSCLE CAR!!!!! MAY ITS REIGN NEVER END

1983Z28 350w/ edelbrock performer RPM power package with 64cc aluminum heads, dynomax shorty headers, 700R-4 with shift kit, 750cfm carb, edelbrock 3" exhaust system, ASCD SS hood, 16" IROC rims.

future mods:
completely done over suspension, black paint with flames, Hurst shifter, dakota digital gauge package, procharger supercharger.

Big454blockchevy

I wonder how a holley would do?I already know the answer . Holley would outperform the qjet.

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Big 454 72 Chevy Nova
383 86 Camaro Z28

[This message has been edited by Big454blockchevy (edited March 12, 2001).]

Damon

I love the QJet but that seems a bit extreme.

Are you sure you were actually getting to full wide open throttle with the Edlebrock? Sometimes factory throttle linkages don't like to work correctly with aftermarket carbs without a little massaging. It almost seems like you aren't getting into the secondaries. I've been tripped up by simple stuff like this more than once myself.

chris83z28

No, I did not change the rods or jets. The motor is just a 250hp 350 with a very mild cam. I guess I figured that it would be fine out of the box with some minor tuning. If it is running too lean, why was I getting 2-3 mpg less gas milage than the qjet? There was no detonation. I made sure all of the vac were in place and rechecked the gaskets and all seals. Maybe if I increased the jet size or changed the rods...? That still donen't account for the fact that I had to adjust the damn thing about every four days in order to maintain tune. If the weather changed more than 30 degrees, I was under the hood.

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1983 Camaro Z28
Goodwrench 350ci V8, Edelbrock TES Headers, Flowmaster Catback, MSD 6al and Blaster 2 coil, Edelbrock Performer intake, (Edelbrock Performer 600cfm carb.)- went back to q-jet!!! T5, 373 rear, Eibach springs, Cervin Vega speakers, Rock. Fos. Sub, Pioneer CD,
email-chris4421@hotmail.com
-------------------------
"I used to be a Mustang Guy! I didn't know the power of the dark side!!"

chris83z28

By the way, those times were with a g-tech so the mph was too high.

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1983 Camaro Z28
Goodwrench 350ci V8, Edelbrock TES Headers, Flowmaster Catback, MSD 6al and Blaster 2 coil, Edelbrock Performer intake, (Edelbrock Performer 600cfm carb.)- went back to q-jet!!! T5, 373 rear, Eibach springs, Cervin Vega speakers, Rock. Fos. Sub, Pioneer CD,
email-chris4421@hotmail.com
-------------------------
"I used to be a Mustang Guy! I didn't know the power of the dark side!!"

Biochem

Ditto!



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1984 z28 w/ a 357 cu in. monster engine which is looking like the posterchild for Edelbrock with the exception of the Holley 750vac... all the suspension stuff... 9-bolt posi disk is in...

-=ICON Motorsports=-

86TpiTransAm

All I gotta say is "preference"!! I know you wouldn't be able to convince my friend to give up his 750 edelbrock!!! 700+ HP with nearly 600 ft pounds of torque in his little S-10!! B'sides no one bothered to mention anything about the longevity and durability of these CC qjets!! Adantage there....edelbrock!! As far as all you "Holley" fans....this post is about the comparison between edelbrock and qjet so take your posts elsewhere!! Throw a 3rd element (Holley) into the mix and you're likely to get a bad reaction!

Jer82Z28

I can't believe you lost a whole 10mph with the edel, perhaps your throttle linkage isnt opening the carb all the way? I had that exact problem when I installed my edel, man was that a pleasant surprise

BTW aren't Demon carbs made by holley?
thats what I always though, I would love one of those, maybe someday...

AlkyIROC

That's something I never considered with the swap. I had to make sure my butterflies opened all the way when I put on my demon. the linkage was actually pulling it too far and I had to fabricate a throttle stop to keep it from bending brackets.

Reinstall and make sure the butterflies are opening all the way.

Demons are made by Barry Grant. When they were called Claw carbs (Gold Claw, Silver Claw etc) they looked to much like a Holley and Holley forced them to change the design. Most of the Holley parts are interchangable with it but the Demon is a better design.

[This message has been edited by Stephen 87 IROC (edited March 14, 2001).]

84FTA

My apologies. However, I refuse to debate G-Tech times. It's very hard to compare two things with an inaccurate measuring device. While it is good in comparasion tests, such as this would seem, 1 sec to G-Tech is probably not 1 sec at a real track.

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1984 WS6 Hardtop Trans Am
Former L69 Car under restoration
1984 T-top Trans Am
4-bolt main 350, performer intake, headers, Holley 650, T-5, hayes clutch, dual elec. fans and 3.23's.
Daily driver and restoration
13.98 @ 101

taliesian

what gasket setup do you use to mate your carb to intake? I have only found one gasket that would stop vacume leaks without a adapter plate

chris83z28

I strongly disagree with the gtech not being accurate (at least with the times). I have tested this one time and time agian at the drag strip and it consistantly reads +- 1 tenth. Some may not be this accurate but mine is proven. Look at the three times. Do you think that it isn't consistant? As far as the adapter plate, I have an edelbrock performer intake, I just used a 1/4" gasket with different studs for the edel. carb. I checked for leaks by spraying carb cleaner around the base.

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1983 Camaro Z28
Goodwrench 350ci V8, Edelbrock TES Headers, Flowmaster Catback, MSD 6al and Blaster 2 coil, Edelbrock Performer intake, (Edelbrock Performer 600cfm carb.)- went back to q-jet!!! T5, 373 rear, Eibach springs, Cervin Vega speakers, Rock. Fos. Sub, Pioneer CD,
email-chris4421@hotmail.com
-------------------------
"I used to be a Mustang Guy! I didn't know the power of the dark side!!"