[Claude Fair]

I have a 1970 Z with stock SU carbs.Back in 1994 I lost my 1973 to a flood.it had webber carbs(3). I am thinking of rebuilding these and putting them on my 70.
How much power will I gain and do you have to constantly adjust the webbers?
Someone just let me know if it is worth fooling with.
Thanks,Claude

 

[Yuichi]

Claude,

You ever get those headlight cover pieces? Hope they were the right ones!

Anyways to your question. Weber carbs are really meant for higher hp engines? Are you using the stock L24 engine, is it an L28? if they are bone stock engines I think that SU's are a better choice. Reason is because they are easier to tune, and you get better mpg.

If you decide to go the SU route. Check out www.Ztherapy.com
they have a really nice rebuilt set of SU's that look **** good! and would really compliment your new paint job. They really do a great job. If that is to expensive for you, you can purchase their all about SU's video, and a rebuild kit and learn on working and tuning the carbs from the video.

Good luck Claude!
zya
Yuichi
Zdriver.com
StrictlyZ.com

 

[Matt 78Z]

I guess you didn't get much chance to work with the webers on your 73? If they are alreadly jetted for the 240 then put them on it would only be time involved. Once you rebuild them they will hold adjustments very well. You will pick up mostly low end power on a stock engine. As long as the chokes are not too big you won't lose power anywhere. I run webers on a highly modded 2.9L that sees 7500 rpm regularly and extended high rpm driving. I spend about 15 minutes everyother week just to check the balance and it is usually where I left it sometimes vibration will slightly alter your adjustments. I think that if I had my suspension mounted in the stock rubber bushings instead of urethane and did away with my solid diff mount that the webers would very rarely need to be touched.

Run a heat shield, fabricate one if you don't have one but it will make your engine run alot more consistent.

Matt

 

[Tony D]

Not fussy adjustments.

I have rubber mounts, and the vib isolators on my triples, and have not had to adjust balance since installing them in 87...
Idle I adjust with the mixture screws, but I doubt I really make much of a difference. Once dialed in on the dyno and drivability is where you accept it, there is nothing more you need do. Ocassional checks.
But I'm with Yuichi on this one---if it's a stocker, your mileage will be better with the SU's, with little sacrifice in power at all. Most of the gains with Webers are in the area over 6000 rpms, and how often do you operate there?