Posted October 4, 200321 yr comment_51954 I have twin weber dgv's on a 73 240z with a 2.5 exhaust. The carbs are not tuned really great but they are the best I can get them. Is there only one screw on DGV's? When I accelerate hard from anywhere around 5-10 miles an hour I will lose all power right when i hit 60 usually right when i shift to third gear. The engine just kinda makes a vrrhhhhhh sound when i try to give it gass, it will slowly rev but wont have any power behind it. I just have to let it sit there while i coast and wait for it to regain itself, then it is fine again. I dont know the psi to the regulator, but i only run an electric fuel pump and there is some type of fuel regulator there (no psi rating). Also I have not had the valves adjusted yet, I have only had the car for a few hundred miles, but the previous owner said they probobly need it...Also does anyone know where I can order new pieces of the DGV, one of the idle mixture screws is stripped and wont stay in with the spring on it...Thanks guys Link to comment https://www.classiczcars.com/forums/topic/8215-loss-of-power-at-60mph/ Share on other sites More sharing options...
October 4, 200321 yr comment_51962 Could be anything from not being tuned to a clogged up secondary jet... Link to comment https://www.classiczcars.com/forums/topic/8215-loss-of-power-at-60mph/#findComment-51962 Share on other sites More sharing options...
October 4, 200321 yr comment_51987 this is off the top of my head, butcheck your vaccum advance and your coil set up,make sure all connections are good (both electrical and vaccum)I know it sounds weird but my Z did what yours is doing, and it turned out that my coil was bad and my advance was off.loss of power under a load but idled just finehey, it's just one suggestion from one guy but what the heck, right? Link to comment https://www.classiczcars.com/forums/topic/8215-loss-of-power-at-60mph/#findComment-51987 Share on other sites More sharing options...
October 4, 200321 yr Author comment_51993 You may be right. I Have the stock distributor hooked up but have a mallory with no vacume advance ready to go in a few days. So the vacum is just plugged. this could be the problem, I guess, because when i set the mechanical advance I seemed to be turning it alot! and it still was not linned up... I'll c if i can get it hooked up real quick, oh and by the way what do you guys think of the mallory dual pt ignition w/ no vacum advance...thanks Link to comment https://www.classiczcars.com/forums/topic/8215-loss-of-power-at-60mph/#findComment-51993 Share on other sites More sharing options...
October 5, 200321 yr Author comment_52091 OK,I plugged every hole in the little vacum bar above the manifold except one, which i put a 1/8th inch brass barb on. I ran 5/32 rubber hose to the vacum advance on the distributor. I does not seem to make much of a difference. My timming is still off, and quite a bit off. I did not have two people so I could not rev it and see if the vacume advance was working.When I shoot it with the timming light (on the 1st or 6th plug wire) the mark is about an inch or two above the indicator. I turned the mechanical advance and far as I could counter clock to try to get it to match up. I dont know why it is off so bad. Maybe my timing chain? Maybe my plug wires are one off in the distributor cap??? I dont know. Anyway, thats what I got thanks guys Link to comment https://www.classiczcars.com/forums/topic/8215-loss-of-power-at-60mph/#findComment-52091 Share on other sites More sharing options...
October 5, 200321 yr comment_52097 were all these adjustments made on the old distributor?If so, there is another screw that holds the adjuster plate on to the distributor, its on the bottm side of the plate and can give another 10 degre? of adjustment. if its loose, it can kick things out of adjustment even though everything appears tight.good luck. Link to comment https://www.classiczcars.com/forums/topic/8215-loss-of-power-at-60mph/#findComment-52097 Share on other sites More sharing options...
Create an account or sign in to comment