HI There, I am looking to pick some brains! I have just purchased a 1977 308 GT4, the car is running dog rough it looks very much like a timing related issue. I have noticed in some of the old invoices that the car was serviced some 4 years ago and it that particular service it had a new twin distributor lead set fitted,yet in 2005 there is an invoice detailing the supply of a lead set for a single distributor model? Question, would converting the car to single dizzy be feasible and would the car run properly or would this coversion not be compatible with the cams,because as much as I have tried I cannot get enough movement on the distributor to time the ignition. Your comments would be grateful. Best Regrads Jazz
If it were me I would take this opportunity to convert it to electronic ignition. This would do away with any current or future ignition timing problems.
Don't start to boil the ocean until you find the problem. You would need to post more info on what dog rough means. The cost to convert is somewhere between $1000- 2000 depending on what you do. I would go back and check the standard stuff like plugs , extenders , wires , cap , rotor , points and then carbs. You did not mention what the advance is at idle and if you have points. Next is the r1/r2 circuit still in place. What is the present timing and what is is at 5000rpm. So you need more info here before things can get narrowed down. Its just a V-8 carb motor and the symptions would be typical ign. or carb issues.
There are two different distributor drive mechanisms on 308s that I know of, one splined and one dogs. With the splined drive (at TDC for refrence) just remove the three nuts holding the dist on, pull the dist out a bit, rotate the rotor one spline and push it back in and you will have more range of adjustment in the direction you moved the rotor. The slplines are very fine for this purpose. I've never dealt with the dogs, so I'm not sure how fine adjustment is done on those.
Well stated, there's no reason not to get the stuff you have working. It's straight forward and will do the job just fine. Once you know what the real condition of your engine is (impossible to tell if it's "dog rough" for unknown reasons) you can upgrade ignition stuff if you want. Resist the temptation to make too big a project out of it until you know what you're working with.
I got a single 8 cyl dist. from Dennis Mccann for what I remember to be $700. It came with new wires; my old ones looked good but I now believe they were my running problem. I did not realise that the 8 cyl dist is actually 2/4 cyl dist's in one housing. At some point I'll convert to pointless ign., in the mean time the car runs great. Cheers, Tom B.
The engine is acting in two separate phases,the revs are holding up when off throttle and it is spitting back on one bank of carbs,it is like the timming of one bank is not running syncronised with the other,I have pulled out the dizzy to turn on the spline but I still can not get adjustment,would it be the phasing of the points? Best Regards and many thanks to all for their assistance. Jazz
Please take us all back to the beginning. What do you consider "dog rough"? Does the car idle smoothly? Is it 1000rpm and what is the timing mark for each dizzy (1-4 , 5-8) . Is the timing being checked with the r2 points out of the circuit. Did you verify the ohm value of each sparkplug wire and the extenders. Is the point gap correct and the condensors checked or replaced. Are the dizzy caps checked and verified they are good. have you verified that the dizzy advance weights are lubricated and operating correctly. Also verify if the coils are working correctly. So make a list and check off each item as you verify it and by the end of the day if all of these check out and you still have the problem then you will need to get into the carbs but that should be your last resort. I do have an assumption here that no one else has been in to screw up the carbs.
Hi Steve, Many thanks for your response, The car when started up runs erraticley in so much as when revved up and allowed to drop to it's idle still holds up in the revs and only very slowly does the revs drop off. This acompanied by the front bank of carburettors spitting back through the venturi's and also hesitation when trying to rev,as you can gather not a very satisfactory state of affairs! I have driven the beast along the road and kept my foot planted to the floor,the car is spitting and snarling through to 5000 rpm then it pulls almost clean right through to 7600rpm ,on lift off the throttle you have to use the engine braking to reduce the revs back down again. I have a new distributor cap plus coils,the distributor itself bob weights etc are functioning as per specification,the only problem that has come to light is when number one cylinder fires the next clyinder firing position ie points opening it not in line with the contact in the cap,I have today sent the distributor to Bob Houghton Ferrari in Glouscestershire,they have the bench set up equipment to set the contact breakers,on return i refit the distributor and take it from there. I shall keep you posted as to the outcome. Best Regards Jazz
Well, I have a nicely melted piston from one of my cars sitting on a shelf. Previous to my ownership it ran with the timing off on the forward bank and with the carbs far out of sync on lean jets with hot cams, so much so that the engine ran entirely on the 7 & 8 cylinder carb at idle. Is it any wonder number 7 & 8 burned? No offense, but running a car that is obviously spitting and popping and losing power is really asking for major engine damage. Whenever your engine loses power, runs noticably rough, and/or is popping or spitting excessively from one bank, its time to park it and diagnose the issues, not floorboard the sonofabieach and rap it out to 7600 RPM. You wont hear the piston melting above 5000, of that you can be sure. First lose the R2 points, set the gap on R1, and check points dwell. Then set idle speed timing, then check it at the advance timing mark with engine at 5000 rpm. You cant look at the wires only visually, you have to check them with an ohms meter also. You have to visually inspect the plug extensions for burns. Slap on new condensors, any auto parts store will have some 400mfs that will work. Once you have done all that, then, and only then, you should move on to the carbs. Good luck.
