New Distributor Question
Thread Starter
Racer
Joined: Aug 2005
Posts: 377
Likes: 3
From: Northville MI
New Distributor Question
Good morning; I would like to say thanks for all the help provided by this site. It has been are very useful tool in my quest for knowledge on my 75 L-48;
I was looking to upgrade the original distributor, wires and plugs; Christmas is coming! The car has 35K miles, I was thinking of a complete Mallory HEI with Matching wires. Is this a good choice? The Car is all original but I will be going to a MID American SS True Dual with Polished Turbo Mufflers.
The Car hestiates like crazy and sometimes backafires a bit; will the new Electrical help with this condition? Or should I be looking for a Q-Jet Re-build; in that case where can I have that done? I'm just not that confident with Carbs yet!
Thanks
I was looking to upgrade the original distributor, wires and plugs; Christmas is coming! The car has 35K miles, I was thinking of a complete Mallory HEI with Matching wires. Is this a good choice? The Car is all original but I will be going to a MID American SS True Dual with Polished Turbo Mufflers.
The Car hestiates like crazy and sometimes backafires a bit; will the new Electrical help with this condition? Or should I be looking for a Q-Jet Re-build; in that case where can I have that done? I'm just not that confident with Carbs yet!
Thanks
Melting Slicks
Joined: Sep 2004
Posts: 2,655
Likes: 19
An upgraded ignition will not improve a basically stock engine over a good functioning points ignition.
1) If the old wires/plugs/points/condenser are old, replace those. Inexpensive.
2) Check for vacuum leaks. Fix those.
3) Set timing, be sure centrifugal and vacuum advance work too.
4) tune the carb. If there are still problems, rebuild it.
5) If there are still problems, run a compression or leak down test.
You can do all this for about 1/4th of what you would spend on the new distributor.
1) If the old wires/plugs/points/condenser are old, replace those. Inexpensive.
2) Check for vacuum leaks. Fix those.
3) Set timing, be sure centrifugal and vacuum advance work too.
4) tune the carb. If there are still problems, rebuild it.
5) If there are still problems, run a compression or leak down test.
You can do all this for about 1/4th of what you would spend on the new distributor.
Thread Starter
Racer
Joined: Aug 2005
Posts: 377
Likes: 3
From: Northville MI
Originally Posted by Garys 68
An upgraded ignition will not improve a basically stock engine over a good functioning points ignition.
1) If the old wires/plugs/points/condenser are old, replace those. Inexpensive.
2) Check for vacuum leaks. Fix those.
3) Set timing, be sure centrifugal and vacuum advance work too.
4) tune the carb. If there are still problems, rebuild it.
5) If there are still problems, run a compression or leak down test.
You can do all this for about 1/4th of what you would spend on the new distributor.
1) If the old wires/plugs/points/condenser are old, replace those. Inexpensive.
2) Check for vacuum leaks. Fix those.
3) Set timing, be sure centrifugal and vacuum advance work too.
4) tune the carb. If there are still problems, rebuild it.
5) If there are still problems, run a compression or leak down test.
You can do all this for about 1/4th of what you would spend on the new distributor.
Thread Starter
Racer
Joined: Aug 2005
Posts: 377
Likes: 3
From: Northville MI
Originally Posted by gtr1999
The stock 75 HEI isn't bad. I would get a kit like Lars used to supply and a new modual and leave it at that. It should be more then enough for what you need.
Gary
Gary
Melting Slicks
Joined: Sep 2004
Posts: 2,655
Likes: 19
This is the first Gary.
Oops, was thinking points.
But all the other stuff on my list still goes.
BTW, module can be bought at any parts store.
Autozone and Advance Auto have advance curve kits on their aftermarket shelf for lighter springs.
Gary
Oops, was thinking points.
But all the other stuff on my list still goes.
BTW, module can be bought at any parts store.
Autozone and Advance Auto have advance curve kits on their aftermarket shelf for lighter springs.
Gary
Thread Starter
Racer
Joined: Aug 2005
Posts: 377
Likes: 3
From: Northville MI
Originally Posted by Garys 68
This is the first Gary.
Oops, was thinking points.
But all the other stuff on my list still goes.
BTW, module can be bought at any parts store.
Autozone and Advance Auto have advance curve kits on their aftermarket shelf for lighter springs.
Gary
Oops, was thinking points.
But all the other stuff on my list still goes.
BTW, module can be bought at any parts store.
Autozone and Advance Auto have advance curve kits on their aftermarket shelf for lighter springs.
Gary
Tech Contributor
Joined: Aug 1999
Posts: 15,175
Likes: 3,986
From: Connecticut, USA
ok this is the second Gary, damm too common a name! 
Look at the summit catalog for the spring kit, and tuneup kit with a HP modual. I have the info on Lars tune procedures somewhere unless he or somone else gets them to you first I'll send them.
Gary
Look at the summit catalog for the spring kit, and tuneup kit with a HP modual. I have the info on Lars tune procedures somewhere unless he or somone else gets them to you first I'll send them.
Gary
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Racer
Joined: Jul 2005
Posts: 317
Likes: 0
From: PA
I have th 75 l-48, it's a dog!! you would be surprised what you can get from a properly set timing curve, I find no problems with the stock 75 ignition. What kind of exhaust do you have?? And the stock Q-jet works fine, I've seen guys set those up and run them on 10 second drag cars. Lars has all the papers on you timing and Q-jet, there good!!There are plenty of low cost things you can do to get more power, not a rocket, but enough without going crazy spending money.
Le Mans Master
Joined: Mar 2004
Posts: 7,493
Likes: 1,502
From: Little Rock AR
I would overhaul the distributor first to free up the likely sticking advance mechanisim and add a curve kit. That should help a bunch.
I would not start in replacing anything else in the distributor just yet. A basic tune up with wires and plugs as needed. Then see where you are at. The HEI is pretty good as-is and you are probably just suffering from years of neglect. You need to have the basics covered before you start in on the faster stuff.
JMO
-Mark.
I would not start in replacing anything else in the distributor just yet. A basic tune up with wires and plugs as needed. Then see where you are at. The HEI is pretty good as-is and you are probably just suffering from years of neglect. You need to have the basics covered before you start in on the faster stuff.
JMO
-Mark.
Thread Starter
Racer
Joined: Aug 2005
Posts: 377
Likes: 3
From: Northville MI
Originally Posted by pauvil
I have th 75 l-48, it's a dog!! you would be surprised what you can get from a properly set timing curve, I find no problems with the stock 75 ignition. What kind of exhaust do you have?? And the stock Q-jet works fine, I've seen guys set those up and run them on 10 second drag cars. Lars has all the papers on you timing and Q-jet, there good!!There are plenty of low cost things you can do to get more power, not a rocket, but enough without going crazy spending money.
Thanks guys for all the input! Again, great site and always helpful!
Thread Starter
Racer
Joined: Aug 2005
Posts: 377
Likes: 3
From: Northville MI
One more quick question: Has anyone had experience with with Wires that are pre cut that actually fit? Also is there any need for the 8.8mm over 8mm? Summit has a lot of wire options....
I did find a Spring advance kit from Mr. Gasket.
I did find a Spring advance kit from Mr. Gasket.
Racer
Joined: Jul 2005
Posts: 317
Likes: 0
From: PA
Still using the wires that came with it, the exhaust will make a nice difference, get headers as well if you can, If you change that and get that timing curve straightened out and tune the carb, you'll feel like it's a different motor. Again, not a rocket, but not an insult to the car. Good Luck.
Thread Starter
Racer
Joined: Aug 2005
Posts: 377
Likes: 3
From: Northville MI
Originally Posted by pauvil
Still using the wires that came with it, the exhaust will make a nice difference, get headers as well if you can, If you change that and get that timing curve straightened out and tune the carb, you'll feel like it's a different motor. Again, not a rocket, but not an insult to the car. Good Luck.
Tech Contributor
Joined: Aug 1999
Posts: 15,175
Likes: 3,986
From: Connecticut, USA
As for the kit, I'd have to look up what's in it. If you post the question for Lars I'm sure he'd respond.
For exhuast I found Jack Horner at East Tenn corvette to make the best fitting pipes. I used some of the better know exhaust vendors and was really disappointed with the fit, it was plain crappy. For our 75 I bought rear pipes from Jack, some mandrel bent sweeps from JC Whitney, Flowmaster 40's and headers. I made the offsets and fit the pipes in the back yard on jack stands. Cost me about $300 for it all and the shops wanted $1,000. You'll need a chop saw and welder. 2.5" free flowing pipes will add about 30 HP from Ganey's old post info.
Where's Ganey anyway??
Do th eexhaust, ignition, tune it good and see how it runs. BTW I don't use made up wire anymore- they are either too long or too short. Buy a good wire crimping tool like the Summit or MSD barnd and then use universal wires to taylor them to your application.
Gary
For exhuast I found Jack Horner at East Tenn corvette to make the best fitting pipes. I used some of the better know exhaust vendors and was really disappointed with the fit, it was plain crappy. For our 75 I bought rear pipes from Jack, some mandrel bent sweeps from JC Whitney, Flowmaster 40's and headers. I made the offsets and fit the pipes in the back yard on jack stands. Cost me about $300 for it all and the shops wanted $1,000. You'll need a chop saw and welder. 2.5" free flowing pipes will add about 30 HP from Ganey's old post info.
Where's Ganey anyway??
Do th eexhaust, ignition, tune it good and see how it runs. BTW I don't use made up wire anymore- they are either too long or too short. Buy a good wire crimping tool like the Summit or MSD barnd and then use universal wires to taylor them to your application.
Gary