hwvigo Posted February 20, 2015 Share Posted February 20, 2015 (edited) Hello, I am hiving a issue that I have been trying to fix for some time now, from a stop in hard acceleration my car bogs very bad. I have messed with timing and checked for vacuum leaks and cant find anything so I decided to turn to the most trusted people on the internet you guys. Engine specs - GM 350 small block - L-82 350ci/350hp GM Camshaft, Hydraulic Flat Tappet, Duration @ .050 in. 222/222, Lift .450/.460, - Stock 350 truck heads with porting - Stock valves ,rockers ,lifters, push rods, connecting rods ,and pistons - 1 rams horn exhaust manifold with porting , 1 standard exhaust manifold with porting - holley street dominator open plenum intake - edelbrock 650 cfm carb - MSD street fire HEI distributor with matching wires - Accel header plugs - timing set to 14 deg initial adv Transmission - TH 350 stock GM - B&m shift kit - Stock stall Here is a vid of the bog in question bog @ 2:52 from a roll it seams to be fine roll pull @ 1:46 Any help or ideas would be a great help thanks. Will S. Edited February 20, 2015 by hwvigo Quote Link to comment Share on other sites More sharing options...
Miles Posted February 20, 2015 Share Posted February 20, 2015 What have you checked so far? Check the basics: fuel pressure, float settings, jets, metering rods, advance etc. If the problem exists after diagnosing the usual things consider: I had a similar problem using Edelbrock 650 cfm carbs on two SBC 350 240Z projects. After wasting a lot of time and money "tuning" the Edelbrock carbs, I switched to Holley Street Avenger carbs and the engines no longer boged plus the off-idle throttle response was excellent. The difference between Edelbrock and Holley was night and day. Out of the box the only thing I did with the Holley was to use stiffer springs to delay the onset of the secondaries. Quote Link to comment Share on other sites More sharing options...
hwvigo Posted February 20, 2015 Author Share Posted February 20, 2015 I have adjusted the floats per edlebrocks tuning guide and been through the whole carb and checked it and set it all per the edlebrock tuning guide from there web page. As far as fuel pressure I have never checked it I am running a mechanical fuel pump so what ever stock is I would assume. The distributor is vac advance and pulls 30 ish deg at 2200 rpm and initial adv is set @ 14 deg. Quote Link to comment Share on other sites More sharing options...
Miles Posted February 21, 2015 Share Posted February 21, 2015 Your car sounds good otherwise. You are not running a big engine so the mechanical fuel pump should be ok. I know the Edelbrock tuning guide well. I tried a variety of jet and metering rod combinations without any improvement. Another problem I had with every Edelbrock carb was stalling under hard braking or cornering. It is a float thing. I finally concluded that I could use the Edelbrock carb as boat anchor and replaced it with Holley Street Avenger five years ago. Did one dyno run and haven't had any issues since. Please post how you resolve this. Quote Link to comment Share on other sites More sharing options...
hwvigo Posted February 21, 2015 Author Share Posted February 21, 2015 Well the fule cut under hard turning and braking now makes much sence. I had a heck of a problem with it at the auto cross last year. I ended up turning my idle way up to try to fix it as a stop gap at the track I did not work 100% but helped a touch. Well time to see if I can find a Holley and test a carb change out. Thanks Miles Quote Link to comment Share on other sites More sharing options...
Miles Posted February 21, 2015 Share Posted February 21, 2015 The Holley Street Avenger uses vacuum secondaries which can be adjusted using their secondary spring kit. Let us know how it works out. Quote Link to comment Share on other sites More sharing options...
jt1 Posted February 21, 2015 Share Posted February 21, 2015 Which street dominator do you have? If it's the single plane one, it's not a good match for the rest of your engine. Too much plenum for that cam and carb. Are you checking timing with the vacuum disconnected and plugged? Have you tried some more timing? Are you sure there aren't any vacuum leaks? jt Quote Link to comment Share on other sites More sharing options...
Redwine automotive Posted February 22, 2015 Share Posted February 22, 2015 The stumble that i hear when u start from a dead stop could be in your accelerator pump adjustment. Try moving linkage on the pump arm and see if it helps. Also check you coil output HEIs should jump at least an inch gap. Quote Link to comment Share on other sites More sharing options...
hwvigo Posted February 22, 2015 Author Share Posted February 22, 2015 Which street dominator do you have? If it's the single plane one, it's not a good match for the rest of your engine. Too much plenum for that cam and carb. Are you checking timing with the vacuum disconnected and plugged? Have you tried some more timing? Are you sure there aren't any vacuum leaks? jt It is a single plane and I have never liked it on the car I was running it with a Holley 650 dp for a while before I got the edlebrock but it started having flooding issues so I stuck the Brock on. Yes I am checking timing with it disconnected and plugged. I am fairly sure but it can't hurt to check aging. Quote Link to comment Share on other sites More sharing options...
hwvigo Posted February 22, 2015 Author Share Posted February 22, 2015 The stumble that i hear when u start from a dead stop could be in your accelerator pump adjustment. Try moving linkage on the pump arm and see if it helps. Also check you coil output HEIs should jump at least an inch gap. I have tried all settings per the edlebrock tuning guide with no luck. The coil is working very well and is very strong. Quote Link to comment Share on other sites More sharing options...
Redwine automotive Posted February 22, 2015 Share Posted February 22, 2015 I hear the same thing at 0:50 ,does it feel like more then one cylinder misfiring . Where do you have dist advance, manifold or ported . Quote Link to comment Share on other sites More sharing options...
jt1 Posted February 22, 2015 Share Posted February 22, 2015 If I was going to stick with the single plane, I would go back to the 650 dp. It will give you a lot more pump shot and more tunability to deal with that much plenum. if you want to stick with the Eddy, I would definitely go to a smaller dual plane intake, maybe a performer or a sp2p, or one of the dual plane holleys. If it was mine, I would work towards the 650 DP with a performer rpm, some headers, and a good flowing exhaust. Then spend some time with a wideband and work on the carb. If you haven't tried some more timing, both initial and advance, I would also try that. jt Quote Link to comment Share on other sites More sharing options...
hwvigo Posted February 23, 2015 Author Share Posted February 23, 2015 I hear the same thing at 0:50 ,does it feel like more then one cylinder misfiring . Where do you have dist advance, manifold or ported . Manifold Quote Link to comment Share on other sites More sharing options...
hwvigo Posted February 23, 2015 Author Share Posted February 23, 2015 If I was going to stick with the single plane, I would go back to the 650 dp. It will give you a lot more pump shot and more tunability to deal with that much plenum. if you want to stick with the Eddy, I would definitely go to a smaller dual plane intake, maybe a performer or a sp2p, or one of the dual plane holleys. If it was mine, I would work towards the 650 DP with a performer rpm, some headers, and a good flowing exhaust. Then spend some time with a wideband and work on the carb. If you haven't tried some more timing, both initial and advance, I would also try that. jt Just placed a order for a new intake it's a Summit Racing Street & Strip® Stage 1 Intake Manifolds SUM-226012, and I have a Holley 670 with vacuum secondaries I'm going to put on. For now the whole motor will be getting pulled next year and rebuilt it's been in there for 25 years and needs some love I have a new set of aluminum head 202/160 valve and 6/1 roller rockers it will be getting with a. New exhaust system, I just want it running good for this race season! I have never ran it at the drags and plan on taking it out a few times this year. I don't know how it will do it only made 222hp and 314 trq to the wheels when I Dynoed it this fall so we will see. Thanks for all the help and I will let ever one know how it comes out. Thanks Will S. Quote Link to comment Share on other sites More sharing options...
jt1 Posted February 23, 2015 Share Posted February 23, 2015 That's a good looking divided dual plane. Square bore so no Eddy. Think about what you want to do with the heat risers, if not much cold weather driving block them off. Your engine now can do a lot better than 222/314, intake, exhaust, and some tuning. It's pretty cool you've has a V8 Z for 25 years. I owned a L82 vette a long time ago. If I remember right that cam is on pretty wide centers, maybe 114 or so. They made good power and sounded good. 882 heads were pretty good for the time, although the chambers were too big. Bah. I am about drunk. I will shut up now. let us know how the engine turns out. jt Quote Link to comment Share on other sites More sharing options...
hwvigo Posted March 12, 2015 Author Share Posted March 12, 2015 (edited) Got started on the new intake and carb, just a quick update will give final results when i get it all buttoned up. parts : Summit Racing Street & Strip® Stage 1 Intake Manifold : Holley classic 750 cfm : ARP intake bolts : Mr gasket intake gaskets : Permatex High Tack Gasket sealant : Permatex ultra black silicone Edited March 12, 2015 by hwvigo Quote Link to comment Share on other sites More sharing options...
grumpyvette Posted March 22, 2015 Share Posted March 22, 2015 if your willing to read through a few linked threads, and sub links I,m sure youll find all the info required http://forum.grumpysperformance.com/viewtopic.php?f=55&t=109 http://forum.grumpysperformance.com/viewtopic.php?f=55&t=1790 http://forum.grumpysperformance.com/viewtopic.php?f=55&t=5229 http://forum.grumpysperformance.com/viewtopic.php?f=55&t=1639 Quote Link to comment Share on other sites More sharing options...
hwvigo Posted March 22, 2015 Author Share Posted March 22, 2015 Thanks for all the info guy. I am very sad to say that after 25 years of loyal v8 power the engine has now developed a bad bottom end knock. And it will be sitting till I get to pull the engine, and seeing that I live in a apartment complex my garage is no big enough for the job. I don't know what is going to happen engine wise. Many great options only time will tell. Quote Link to comment Share on other sites More sharing options...
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