The Stig Posted August 13, 2012 Share Posted August 13, 2012 Not what you're thinking! Replaced the Misab plates, balanced the carbs using the airflow tool and Voila, lots more horses became available! Another benefit is that the induction noise on the Crossflow is now much smoother than the previous 'Subaru style' noise which makes a lot of difference at cruising speeds - that was down the carbs not being balanced. Those simple jobs often produce the most satisfactory results Link to comment Share on other sites More sharing options...
scannon Posted August 13, 2012 Share Posted August 13, 2012 What did you use to balance the carbs? I used to use the Unisyn back in the day. It took two of them to balance the carbs on my early 911. What are Misab plates? Link to comment Share on other sites More sharing options...
The Stig Posted August 13, 2012 Author Share Posted August 13, 2012 The carb balancer was this one - available on Ebay in the US as well http://www.burtonpower.com/weber-carb-synchrometer-balancer-web98001-000.html Misab plates are the spacers/rubber mounting plates between the carbs and the manifold which are essential to correct mounting of the carbs as they need to have flexibility - partly designed to minimize frothing of fuel in the float chambers http://www.burtonpower.com/parts-by-category/fuel-system/carb-mounting-accessories/sandwich-plates-misab-40-45dcoe-x-2-set-of-4-webmisab.html I am sure there are threads about carb mounting options but I have always used this style. Link to comment Share on other sites More sharing options...
scannon Posted August 13, 2012 Share Posted August 13, 2012 That looks a lot more accurate than the Unisyn. Prior to that we used a piece of hose held to the ear to balance by the sound of air rushing into the carb. Link to comment Share on other sites More sharing options...
lancylad Posted August 14, 2012 Share Posted August 14, 2012 I use the samecarb balancer, worth its weight in gold. Misabs are the spacers of choice, trick is to not tighten them to much...my webers sound glorious!!!!! Link to comment Share on other sites More sharing options...
bball7754 Posted August 14, 2012 Share Posted August 14, 2012 I have the thicker aluminum (I think) plates with replaceable O rings on both sides. Have considered changing to the Misabs. What reading did you have at idle? Think I'm usually around 7 kg/h. Steve Link to comment Share on other sites More sharing options...
The Stig Posted August 14, 2012 Author Share Posted August 14, 2012 I had the ali plates but the O rings went hard and leaked so replaced with the Misabs. On EBay Uk is cheaper than here. I managed to get about 5.5 reading on the balancer. Smooth idle is 800. The MSD I believe helps that as I was surprised how low the idle went and how smooth the pickup. Of course there is a small flat spot but for my road use, really don't care. Can't beat that Crossflow induction noise! Link to comment Share on other sites More sharing options...
lancylad Posted August 14, 2012 Share Posted August 14, 2012 I have a 1.9cvh, running on a megajolt. Idle approx 850-900, reading of 5.5 -6.0. And yes.....the noise is luverly! Link to comment Share on other sites More sharing options...
bball7754 Posted August 14, 2012 Share Posted August 14, 2012 I'm more at 1000-12000 rpm with my Aldon electronic distributor. Did you convert to full electronic ignition? Link to comment Share on other sites More sharing options...
lancylad Posted August 14, 2012 Share Posted August 14, 2012 My original 1.6cvh had the ford edis unit on board so when did the switch to a 1.9 I converted the new engine to accept the edis and then added the megajolt to that. Seems to work okay and I can program the engine to my liking. Link to comment Share on other sites More sharing options...
The Stig Posted August 14, 2012 Author Share Posted August 14, 2012 I have the MSD but still a distributor with contactless ignition. My previous Crossflow had a full Omex management system and coil pack and no disti which gives great control. The MSD system is superb, starting is awesome. Highly recommended. Link to comment Share on other sites More sharing options...
bball7754 Posted August 14, 2012 Share Posted August 14, 2012 So you have an MSD distributor? Which model? The MSD site seems extremely American V-8 oriented. Link to comment Share on other sites More sharing options...
The Stig Posted August 14, 2012 Author Share Posted August 14, 2012 Apologies, maybe I misled. I have an MSD ignition but standard distributor. You are right, most of the distis looks more appropriate for a V8. Maybe block off half the cylinders or adapt to an Alfa Twin Spark system Link to comment Share on other sites More sharing options...
coffee break Posted August 15, 2012 Share Posted August 15, 2012 Did the Omex ECU control the spark only or was the car equiped with FI? Link to comment Share on other sites More sharing options...
The Stig Posted August 15, 2012 Author Share Posted August 15, 2012 Initially only the ignition but was using an Omex 600 unit so had the FI capability built in so later upgraded to Jenvey TBs. actually quite a bit of work and probably a bit OTT for a Crossflow. But revved to 8,000 very comfortably! Link to comment Share on other sites More sharing options...
twobone Posted August 16, 2012 Share Posted August 16, 2012 (edited) Thanks for the inspiration. I tuned up my car to a much leaner setting using the best idle approach and balanced with my synchro tool. Now it revs cleanly and has lost the "hammering" vibration at cruise speed. Whats interesting is that the carbs were balanced when I started the tune, however the hammering intake and vibration was still there at hier revs Just because the carbs are both pulling the same amount of air doesn't mean the mixture is right. I had previously used the Gunson spark plug view method, but the best lean idle approach has better results. Edited August 16, 2012 by twobone Link to comment Share on other sites More sharing options...
danilo Posted August 27, 2012 Share Posted August 27, 2012 (edited) Misab plate!? Fancy name for another Brit substandard bodge. (yes I've tried those.. Garbage is a polite descriptor in my experiences) Used to buy /fit Alfa Romeo Rubber mounting blocks for Webers. A whole Planet better quality in fit,durability AND vibration isolation Gee.. who woulda thought that Italians, makers of Webers, would have developed a decent mount system?? Edited August 27, 2012 by danilo Link to comment Share on other sites More sharing options...
lancylad Posted August 27, 2012 Share Posted August 27, 2012 Misab. ?..made in sweden. Link to comment Share on other sites More sharing options...
Klasik-69 Posted August 27, 2012 Share Posted August 27, 2012 Thanks for the inspiration. I tuned up my car to a much leaner setting using the best idle approach and balanced with my synchro tool. Now it revs cleanly and has lost the "hammering" vibration at cruise speed. Whats interesting is that the carbs were balanced when I started the tune, however the hammering intake and vibration was still there at hier revs Just because the carbs are both pulling the same amount of air doesn't mean the mixture is right. I had previously used the Gunson spark plug view method, but the best lean idle approach has better results. Have you considered installing an AFR gauge to see if you are running rich or lean, especially at higher rpm and loads. Mine was running lean but I didn't have a clue until I did a dyno run. That likely saved my motor from further damage. Link to comment Share on other sites More sharing options...
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