gideeup68

On a 68 289-2v upgrade...Is a Holley Street Avenger 570cfm carb sufficient to install along with a Edelbrock Performer intake, or is a 600 or 650 cfm necessary? Thanks, Guys, John

65_2plus2

Keep the 570. This will give a 7000rpm redline if the rest of the engine can handle it. Here is a site to calsulate the CFM of a card for a given cubic inch and rpm range. Most stock 2V 289's never exceed 6000 rpm. [sm=smiley20.gif]
http://www.csgnetwork.com/cfmcalc.html

gideeup68

Thanks, 65. Can anyone recommend an upgrade for the distributor? High performance I guess, Ive read it would be needed to get better spark to burn fuel more efficiently? Ive located the high performance plug wires but what about the plugs themselves? Any suggestions and guidance is GREATLY appreciated!!!!! John

65_2plus2

Hay John,

MSD makes outstanding ignition systems to include the distributor. Go to there web site or talk to you local speed shop guy and you will be thankfull you did..[sm=smiley20.gif]
Here is a link. There are alot of others who make great ignition systems also.
http://www.msdignition.com/

Vince

gideeup68

Thanks Vince, I went to that sight and they really have alot to choose from. Easy to navigate around on too and really informative. Thanks again, John.

69FECoupe

With regard to ignition, keep in mind that the ignition voltage requirement is more directly related to compression ratio than anything else. You can put the hottest system in the world on your car and the spark plugs will only use the voltage needed to jump the gap based on your compression ratio. I'm guessing that your motor is basically stock and probably in the range of a 9.0-9.5 CR. That's not real high. If your stock distributor is in good shape, consider installing a Pertronix points eliminator. That, combined with their coil will give you all the spark you need at a very reasonable price.

65_2plus2

I'm not sure I can agree with 69FECoupe,

You can still benifit from a high performance ignition system such as with MSD. Multiple sparks ensure complete combustion and will increase the efficentcy off burn in the cylinder reguardless of compression ratio. Better plugs and 8mm+ wires are also part of the package for better burn.

My 97 cavalier got a little more pep and 4mpg better with a 8.5 compression ratio.

Good luck, Vince[sm=smiley20.gif]

69FECoupe

65_2_plus2, I meant and I mean no direspect. I'm just trying to point out that there are good alternatives to expensive systems. MSD makes good stuff and multiple spark discharge can be beneficial mostly on carbureted engines. That said, I used to run an MSD on my 69. Its a 390/335 with a 428CJ cam, Edelbrock Streetmaster single plane, Holley 600 vac. sec., Hookers, C6, 3:89 9" trac-loc. I removed it after it failed the second time. After doing some research, I decided to go with a factory Ford duraspark set up. I recurved the distributor and experienced no degredation in performance or MPG. Now I can get cheap parts anywhere and it's cost effective to carry spares. Regarding spark energy, keep in mind that even the old points and condenser system with it's weak coil, skinny wires, and inherently self destructive design produced enough energy to ignite the 400+ HP high compression musclecars. The point is you don't need an arc welder to spark a mild street engine. I'd recommend the Duraspark conversion to anyone with a mild combination that spins at less than 6000 RPM. Over the years I burned a ton of money on performance "must have's". Some worked, most had better/cheaper/more reliable alternatives. This grey bearded old fart will get off the soapbox now.

mdvaldosta

I agree with both of you :P

gideeup68

This is what I love about this site.....Its like legalized eavesdropping on others conversations... and gaining invaluable knowledge from their experience....Thanks for that.
How about this (probably common) problem....On my 68 289, after removing stock carb and intake, on the heads at the center port (exhaust? I think) major carbon deposits on both heads ... passenger side 100% blocked, drivers side 90% blocked. Do these need to be cleaned out and if so is there any way possible without removing the heads? Ive heard they lead nowhere and may remain as is...kind of hard to believe so I'm asking. Thanks.