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racer88

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About racer88

  • Birthday 01/01/1956

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    London ontario canada

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  1. Hi Everyone I know our cars are sports cars and as such we should not worry about such mundane thing as fuel economy, but I am curious if any of you that have done a small block ford swap have any thoughs as to fuel economy before and after your swap. Was it better or worse? I have been looking at taking my mildly modified L28 to the next level or swaping to a 289 or 302. Fuel economy is not my main concern but is a consideration as well as many other factors. I have a fairly stock injected 302 from a mustang that would be a great transplant. Bob
  2. racer88

    smelly z

    It was my thoughts that the wide open throttle miss was that it was going lean as the throttle opened allowing more air in as I was already at about 4000 rpm when i crack the throttle wide open if I let off a little bit while it is missing the miss goes away and the car continues to pull hard. maybe I have to stop thinking how a holley would react. I shortened the mounts for the rear bumper and tucked it right up to the body and the exhaust tips are flush with the back of it.
  3. racer88

    smelly z

    Thanks everyone. I now have a plan of attack. I am going to gear up an O2 sensor to record excatly what is coming out the tail pipes and procced accordingly based on what I find. The carbs are in perfect shape as far as throttle shafts, pistons etc. The main jets are right on .100 thou and are perfectly round. The only issue I have is I do not know what needles are in my 4 screw carbs as they have no markings. I know holley and rochester carbs inside and out but the su's are frustrating me. I do suspect that it runs rich at idle and low speeds but turns lean at wide open throttle. If I acelerate at 3/4 throttle is pulls to 6500 and goes like a bat out of hell. If at some point in that run I open the throttle all the way it starts to miss. I have checked fuel pressure and it is steady at 4lb. any ideas thanks again Bob
  4. racer88

    smelly z

    Hi Leon thanks for the response. my exhaust is a 6 into 1 header with a 2 1/2" mandrel bends in stainless that I tig welded together with a stainless magna flow muffler. did check for leaks and found none. My first thought was that I was to rich but if i lean it out anymore I get surging at a constent rpm. I have read many post on this site and classiczcar about the smells of our cars and was wondering if the fuel injection cars had that smell or was it only the carb cars
  5. racer88

    smelly z

    I know there are many threads on the dreaded exhaust smells from our early z's. mine is a 74 with a warmed over 2.8 with round top carbs. i have done all the work on weather stripping sealants gaskets etc. I have read everything on the su's they are in great shape and I think tuned correctly. Having said that I still get the fumes in the cab when going slow or at a light. I understand the aero issues with the car. When i start it up at the local cruise night the people around smell the exhaust as well. My question is do the guy's with the fuel injected cars have the same exhaust smell or is it a carb issue. I am also looking for opinions on putting some sort of after market fuel injection and a high flow cat. if I cannot get rid of the smells I'm afraid i am going to give up on the z and sell. I have had many cars from the 60's and 70's and none have smelt this bad. Thanks Bob
  6. thanks guys all great advice. i am going to do the gm ecu and try to find some type of single tbi. one to replace each su. any ideas as to what size i should look for? My engine is an n42 block with an e31 head that has been ported, large valves added and decked 60 thou. cam is a regrind 245 @ 50 thou lift 470 lift with custom lash caps to move the pattern as close to the pivot as possible to maximise lift and duration. Ported intake, zx dizzy with hei module and lightened flywheel. 6-1 header with 2 1/2 exhaust with a single magnaflow muffler. Sounds like a ferrari at 6800 rpm. i would like to see some sort of performance improvement. I was thinking of finding the same size tbi as the su's. any ideas or tips would be great. I have access to milling machine lathe surface grinder etc, so adapters are a piece of cake thx in advance bob
  7. Thx everyone. I am gonna start cruising to local auto wreckers for tbi's that look like they might do the job. I am gonna use as many stock type parts as I can Will posts pic as the project moves forward Bob
  8. Hi Tony Yep just looking to inject the z without getting into the work and expense of multi port.Thought it might be just as easy to use an exsisting tbi as it already has the tps attached to it The SU's carbs run ok but I would like a little more control over the A/f with the thought of putting a catalytic convertor to try and get rid of some of the exhaust smell. Yes I have done every mod to the car (door rubbers seam sealer etc.) but it still stinks a little bit at idle and low speed. When I start it up at the cruise nights my buddy's are amazed at how it smells. I have worked on the carbs untill I am blue in the face. I did find those Patton adapters in one of you previous posts, where you also mentioned about using a spacer with injectors in them and short air doors. I found that interesting but do not know enough about injector placement to pursue it further. Thx Bob
  9. Hi Guys I am starting to gather parts to buid a gm tbi for my 2.8/260. I am planning on using two one barrel tbi units off of early 90's 4 cyl chevies. A programmable gm ecu. My question is this. Can anyone see a problem with turning the tbi's from horizontal to vetical. I would like to attach them the same position as my su's are now. Machining adapters, linkage and such are no problem, my only concern is to the function and poss atomization probs and or fuel dribbling at slower speeds. Any help or opinions would be great. thx bob
  10. Two cars Mmmmmmmm....... snow tires Mmmmmm........now theres a thought
  11. Thx Tony. It looks like that is the route I will be taking. I will post pic's and updates as the project moves along Bob Ps I wish the weather up here in Canada would turn crappy so I can stop driving the Z and start workin on her!
  12. I was actualy thinking of the complete gm throttle body assembly, but that looks pretty slick. Do you have to alter the carb body or can you change it back if you so desired. I would hate to render a good set of su carbs as un-usable. How close is the gm ecu in fuel requirements to what my L28 would need. This set up looks like just what I am looking for. If I decided to build a system like this would you be so kind as to steer me in the right direction as far as what injectors, ecu throttle position sensor etc. Thanks Bob
  13. Hi Tony Thanks for the ideas. Sunday was tune the car day. I think I have found my distribution problem. When I first got the car on the road about a month ago it surge at a constant 3500 rpm in 4th gear. I searched some threads and determined that the float level was low as I had already tried to fix the surge by adjusting the nozzles up and down. I raised the float level bit by bit until the surge was gone. The car sounded great and ran strong at 3/4 throttle but when I opened it up it layed down, like it was running out of air. It turns out my fuel pump (electric) pressure was intermittently low (2psi)so raising the float compensated at idle made it to rich cruising and went bone lean at high speed. I corrected this issue added new plugs and they look great. I have read many of your post on fuel injection and you seem to have a good handle on injection. I have spent many hours on the dyno tuning holley carbs for late model stock cars but not much experience on su's. I am planning on converting my 260 to injection over the winter. I was thinking of machining up some adapters and mounting a couple of GM throttle body injection units on the su intakes with some sort of stand alone control system eg. mega squirt. Any thoughts on this idea would be great. many of the threads I have read on the induction debate Holley vs su or injection seem to be a few years old. thanks Bob
  14. I have put about a thousand miles on my 260 with 280 engine with 4screw round top su's since I got it on the road this fall. It seems to run great. I have been very carefull to make sure the float level is set correct sync'd both carb at idle and 2,000 rpm. Adjusted the nozzles 2.5 turns down then tweaked from there. I decided to check my plugs this morning and I found cyl. numbers 1,2,5,6 to be bone white cyl. 3 and 4 to be black and sooty. Cyl# 1&2 are connected by the same opening in the intake as viewed from the carb opening. The same goes for 5&6. #1 and 4 have their own runner. Has any one else noticed this condition with their plugs. Not sure if I have an issue somewhere else or is it a normal distribution problem with the su intakes. I tried to richen it up (bone white plugs are never good) but the car seems a little sluggish. Any ideas would be great Thanks Bob M
  15. Thanks everyone for your input. This is my first zcar. I love the car but sure do like to drive with the windows down . Maybe the gas fumes just smelled better back in the 70's. With the crap they put in the fuel today that's probably not far from the truth Bob
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