zliminator Posted December 3, 2003 Share Posted December 3, 2003 And if I do, could I fabricate one? My engine is a 350 SBC in a 240Z. With an 11:1 CR and 505 lift cam the idle is plenty lumpy and it floods out easily. I just got the brakes bled last night and realized that the reason I kept hearing air whoosing in the master cylinder was because the hose connection from the booster to the manifold was not hooked up. (Duh!) I just know that everytime I come to a stop and let off the gas to hit the brakes its gonna die on me in traffic. I was wondering if there's an easy way to fabricate a vacuum canister using a coffee can (or whatever container) and check valve. Any ideas? Thanks folks! I'll be sure to post some pics on my website and leave the link to it in a message. Dan Quote Link to comment Share on other sites More sharing options...
80LS1T Posted December 4, 2003 Share Posted December 4, 2003 Well on my LT1 engine I am running 11:1 compression and a .525/.525 cam(219/228@.050.....LT4 H.C.) and I have no problems with loosing brake booster vaccum. Of course I do have a 280ZX so I suppose the booster for the brakes is different. Does compression even have anything to do with the vaccum of an engine? I thought it was only the cam that played a part in that? Guy Quote Link to comment Share on other sites More sharing options...
Guest zfan Posted December 4, 2003 Share Posted December 4, 2003 Cam does effect it. I am using a crane Vacuum canister and I am running a 236/242-550/540 lift roller cam. I used one as well on smaller cams as I noticed the difference. Mike Quote Link to comment Share on other sites More sharing options...
Guest Z-rific Posted December 4, 2003 Share Posted December 4, 2003 What kind of carb and tranny are you using? Quote Link to comment Share on other sites More sharing options...
zliminator Posted December 4, 2003 Author Share Posted December 4, 2003 The carb is a Holley 750 double and the tranny is a 700R4. Front brakes are from a Toyota 4x4 and rear are 300ZX calipers. Hope that helps. Dan Quote Link to comment Share on other sites More sharing options...
SpeedRacer Posted December 5, 2003 Share Posted December 5, 2003 I have found that the small 240Z vacuum booster is a bit marginal. You can upgrade to the slightly larger 2+2 version however, installing a vacuum canister certainly won't hurt anything. Quote Link to comment Share on other sites More sharing options...
zliminator Posted December 5, 2003 Author Share Posted December 5, 2003 I have a booster from a late model ZX (280 or 300), but my question should have been not if I need one but how it works and how its made. I don't think its more than a can, some tubing, connectors and a check valve. I guess all I need to know is where the check valve goes. Any ideas? Dan Quote Link to comment Share on other sites More sharing options...
Guest Z-rific Posted December 5, 2003 Share Posted December 5, 2003 I don't think you "need" a vacuum canister, I think you just need to tune up your system. A big cam, big Holley carb, and an auto tranny are a combo that can be tricky to get right. Lack of vacuum at idle can lead to a very rich condition. If your 750 DP is flooding out a lot, you may want to get a few sizes of smaller jets and try that. Power valves as well. Tune your carb with a vacuum gauge to get the max vacuum at idle. This will probably involve leaning the mixture even further. Also look at the level of fuel in the bowls. Basically, an overall carb tune up. I'm going through the carb tune-up process as well. I find it to be one of the more enjoyable aspects of wrenching on your own car. It's not greasy, easy to get to, not time too consuming and you get instant results. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.