Chris Laswell Posted December 12, 2014 Share Posted December 12, 2014 going to install an ls1 into my z... want to go carb conversion for simplicity and old school feel.... now with the taller engine height of a carb and air filter... will that cause hood interference? Anyone have experience? Quote Link to comment Share on other sites More sharing options...
JMortensen Posted December 12, 2014 Share Posted December 12, 2014 I can tell you that the edelbrock single plane is .75" taller than the single plane. I made my own mounts, so my experience might be a little different than others, but using a NASCAR air box with a drop base, I've got about an inch and a half to the hood. I'm going to make a cowl induction scoop to clear a 4" filter. 1 Quote Link to comment Share on other sites More sharing options...
JMortensen Posted December 12, 2014 Share Posted December 12, 2014 Oops. Dual plane is taller than single. Quote Link to comment Share on other sites More sharing options...
socorob Posted December 12, 2014 Share Posted December 12, 2014 And the fuel injection is simple to hook up if you decide to go that route. Probably much easier than switching to a carb. Quote Link to comment Share on other sites More sharing options...
rsicard Posted December 13, 2014 Share Posted December 13, 2014 Consider going to an aftermarket throttle body self tuning fuel injection system that will use a dual plane intake manifold. Typically, a single plane is taller than a dual plane intake. Single plane is fine for port fuel injection, not so good for carb. An engine that uses a carb typically, with proper maintenance, does not last much beyond 100K miles because the carb washed down oil in cylinders promoting accelerated cylinder wear. The same is not true for fuel injection as it is more carefully metered than the carb. Something to consider. Quote Link to comment Share on other sites More sharing options...
JMortensen Posted December 13, 2014 Share Posted December 13, 2014 In this case, the dual plane is taller. I believe tube80z has pics of the two side by side. Quote Link to comment Share on other sites More sharing options...
zdlite Posted December 31, 2014 Share Posted December 31, 2014 (edited) I have a carb under a stock 240z hood. The GM single plane is the shortest available intake. LIke Jon said a good half inch less tall than the dual plane. I run a 14" Moroso drop base air cleaner with 3" element and a 750 double pumper. With my homemade mounts I have enough clearance to run a 1/4 to 3/8 inch spacer/insulator. The 240 hood has a pretty good taper to it, so the key is getting the engine back as well as down. I got the engine so far back I moved the heater penetrations in the firewall to clear the starboard head and relocated the hood latch to the side to clear the 14 inch air cleaner. With Corvette accessories the front of the crank pulley is centered on the steering rack. I actually have to jack the front of the motor up an eighth of an inch to change the belt. Should also add I have I think a 1/8 inch spacer between the stock cross member and the body (ala JTR). Have to disagree with the comment about single planes not being good for a carb. GM puts them on their crate motors. Z cars can't really use a lot of low end torque making single planes a better match with a Z: trade some of the low end torque for more high end HP. It is a bit more of a challange to tune an old school double pumper with a single plane LS motor. But a few adjustments to the idle feed restrictor and air bleeds makes the carb as smooth as can be. The car pulls clean from idle. I can drive all day and never go above 2000 RPM and cruise in 5th gear by 35 mph. The newer Holley HP carbs have a different base metering and are a better fit for LS motors. The part about ring wash and engine life is true for cold weather starts, but who the F cares? Road salt means I don't drive much in bad weather. It would take me 25 years to put 100K on my zed. Synthetic oils means even a carb'd LS motor will live longer than a 60's muscle car motor did, so IDK about the 100K limit. By the way, I have yet to see another carb'd LS motor that fits under a stock hood. From what I read on here the John's Cars mounts definitely won't give the needed clearance. Can't speak for other kits, can only tell you what is working on mine. Edited December 31, 2014 by zdlite Quote Link to comment Share on other sites More sharing options...
jhm Posted December 31, 2014 Share Posted December 31, 2014 zdlite hit the nail on the head...it depends almost entirely on your engine mounting. Your original post didn't specify what kind of mounting hardware and configuration you're using, so you might want to provide that in order to get a more definitive answer. The JTR-style installations mount the engine lower and further to the rear, and the Scarab-style installations mount the engine higher and further forward....resulting in huge differences in under-hood clearance. Quote Link to comment Share on other sites More sharing options...
10HBMartian Posted January 30, 2015 Share Posted January 30, 2015 I made some custom motor mounts that dropped the motor 4 inches lower. Quote Link to comment Share on other sites More sharing options...
JMortensen Posted January 30, 2015 Share Posted January 30, 2015 (edited) What kind of oil pan and how far does it hang down past the xmember? If it's 4" lower than the JCI kit I'd think an LS1 pan would be damn near scraping the ground as they're typically 1 or 1.5" past the xmember with JCI. You can do a drop base. Again, I'm using the NASCAR carbon fiber airbox (cheap on ebay and it has a 2" drop base. You can then pick the element height to get the total height you need and you might make it clear the hood if it's really that low. There are regular air filters with drop bases too, if you don't want the duct part. I bought the filter with a drop base just because it was cheaper than buying an element alone. If you want to pay shipping I could send it to you and you could play around with it and see what works. Edited January 30, 2015 by JMortensen Quote Link to comment Share on other sites More sharing options...
Bowtiez Posted January 30, 2015 Share Posted January 30, 2015 (edited) . Edited January 30, 2015 by Bowtiez Quote Link to comment Share on other sites More sharing options...
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