One item that has been eating my lunch for me is a better distributor. I've been hunting a 75 for a few weeks and just now was told it shipped. Ok I've heard it before so I'm not going to hold my breath waiting. I was digging through all the posts of altered distributor advance but none were very clear of how this was done or on which particular model or year of distributor. I found a very good pic in RallyBobs turbo postings that show a lower bracket that none of the early styles had. It was this bracket that was used to limit the advance. I have been looking for a way to get there in a few steps and didn't really find too much. Before I go back into fall back and punt mode I'll try an odd idea or two on one that I already consider not the best and then I'll hold my breath and hope it really did ship this time.
2.0 roller rocket finish
I've been busier than ever and instead of scattering various threads about, If it's ok With you all I decided to put up a newer thread that included some of the getting back to regular gas and a roller install that is coming right up. To be honest I do use the threads as a reference to myself and it allows me to look back and see where I could have done something different or where I found such a great idea.
A quick summary of the last couple of days include the removal and replacement of the back glass. I found and procured a fresh billet cam that has me pretty happy, ok alot of luck on that one. I welded in the plate for the passenger side retractor seat belt and did some interior finish work. I also removed the stock fan and shroud without removing the radiator and installed an electric one from I believe an early Honda. I also did the remote battery mount and tried it all out.
I was told that tomorrow or the next day the cam may ship so I'll be doing this a bit quicker than expected.
If this is ok with you all I'd like to keep up on the documentation, if it is, then I'll work on some pics of the most recent mods and I suppose if the old thread is salvaged they could be merged?
A quick summary of the last couple of days include the removal and replacement of the back glass. I found and procured a fresh billet cam that has me pretty happy, ok alot of luck on that one. I welded in the plate for the passenger side retractor seat belt and did some interior finish work. I also removed the stock fan and shroud without removing the radiator and installed an electric one from I believe an early Honda. I also did the remote battery mount and tried it all out.
I was told that tomorrow or the next day the cam may ship so I'll be doing this a bit quicker than expected.
If this is ok with you all I'd like to keep up on the documentation, if it is, then I'll work on some pics of the most recent mods and I suppose if the old thread is salvaged they could be merged?
1 - 20 of 65 Posts
I've been thinking alot lately of where this whole project is headed. Another summer is about gone and it's hard to judge if I'm closer to it really being drivable or further away. I've pretty much hit my limit of how much money time and effort I'll put into a losing cause. I'm starting to look at the car with disguest and that is not what I had in mind at all when I got it. Almost all of the nitpicky stuff is done and it should be all good but maybe I'm just too worn out. If I had the motivation I could put the other motor in it and just call it good but I just don't have it in me to tackle that. I have no idea of even if I ever get the parts I seem to need if it will help make it more drivable or if it's just money into the pit. If anybody has any ideas where to go I'm still listening.
All right I'm asking for some help on which distributor to use and or modify. I'm posting some of these numbers from memory so I can only hope I'm right. twin DCOM webers jetted 138 mains F64 emulsions 160 air carriers 53F21 idles on a magnalesti manifold. A lightly ported head with stock intakes and 2.0 exhaust valves. 11:1 compression Venolias with all the edges broke except for the piston top outside edges. I was thinking rollers and using a fresh billet cam that is advertised 292 but is 248 at .050 and has .455 lift given the 1:157 roller ratios. I'm at my wits end and could use some help. Bob Does this sound like it could run on 91 octane or am I just dreaming?
I was looking at the modifications to limit the advance in the turbo for Carlisle thread and the bracket where the screws were placed is not on any of the distributors I have. Was this added or is it just a type that I don't have?
Ok I understand this a bit better, depending on the year distributor you have or choose to use it can be limited in two ways that I've come across. On the earlier style it's best to use a small nut and bolt to limit the total advance. I took a pic of a 69 type that had a total of 32-36 total mechanical advance. With the green bolt in the pic added I can limit the space between it and the spring post by some 35 percent to get down to around 22 degrees of total advance. I can bring my initial timing up a bit to around 10 or 12 then.
On the other hand with a 75 type I am a little more limited as to initial timing. with it I'm looking at around 8 degrees initial and 25 mechanical.
I think it's somewhat clearer, thanks.
On the other hand with a 75 type I am a little more limited as to initial timing. with it I'm looking at around 8 degrees initial and 25 mechanical.
I think it's somewhat clearer, thanks.
After I welded in the stop I was checking it with a degree wheel and adjusting it. I have it set at 22 but going lower is really easy. I just reset it to right around 16-18 degrees. That should be a good place to start.
My mechanical advance is set. I pop riveted the breaker plates together as close as I could get to what was it's static start point. I finished this little bit of fun by installing the Crane optics and shutter. The first pic is looking down into it and the second is all finished. I'll try this one first but I also have a 75 that should arrive on Wednesday.
While I'm playing with the timing in anticipation of doing the Rollers. I was thinking it might be nice to do another front pulley just for this motor. Marked at #1 #2 #3 #4 tdc and again at 15 and 35 degree advance marks. I was just thinking that it might make timing and doing the valves alittle easier. Maybe do TDCs in red and timing in white?
this was kinda what I had in mind to do that might make things easier. Red is TDCs and white is 15 and 35 degree marks for timing.
I did notch them all but just continued the lines out some to show the idea. A degree wheel would be nice. On this motor with the twins and cold air intake just getting your hand on the flywheel timing mark is a trick, forget about seeing it. I wonder if a round degree wheel would stick to the front angled face of the pulley? I guess you could tap the front bolt and put something there? Just thinking out loud.
Well I have been back about a day or so and the parts are finally arriving. The first pic is a look at the lobes on that fresh billet next to a stock one. Next is those really pretty solid lifters.
ok the pics are backwards from the text...
ok the pics are backwards from the text...
Just for those that want to see the numbers I'm posting the cam card on that monstreous cam. I'm also posting a pick of a varience between a 75 breaker plate and an earlier one. Note the difference in the advance retard attachment point being moved from one side to the other.
I was doing some planing of this weekends work in my head today and it just dawned on me that the timing gear will be in the way of slipping the old cam out and the new one in. I remember years ago jacking up the front of the motor to clear the radiator support to pull one but can't remember how I got past the gear. Any suggestions or ideas would be nice.
Ok I've hit a few minor snags in the plan so far. To start I noticed that the distributor housing for the 69 doesn't have a cut out for the notch to align the cap on it. I overcame this one by using a 72 distributor body with a 69 advance unit and a 73 shaft. I used one spring from the 69 and 1 from the 75. It has an early year breaker plate so I think I've scavenged pretty much every year I have parts from.
I was concerned about valve spring bind and Jim had the idea to test the rollers and cam in another head not on the 2.0. I picked a 73 head that just had springs and valves similar to what is in the 2.0. To make a long story short I'll be pulling the head off of the 2.0 to fix a spring bind issue on the exhausts. The intakes were ok with the new .4546 lift but the stock exhausts were in full bind. I think I'll change out the exhaust to use intake springs and eliminate a few items to get the spacing right. I'll try it on this other head first and just duplicate it on the head for the 2.0.
I was concerned about valve spring bind and Jim had the idea to test the rollers and cam in another head not on the 2.0. I picked a 73 head that just had springs and valves similar to what is in the 2.0. To make a long story short I'll be pulling the head off of the 2.0 to fix a spring bind issue on the exhausts. The intakes were ok with the new .4546 lift but the stock exhausts were in full bind. I think I'll change out the exhaust to use intake springs and eliminate a few items to get the spacing right. I'll try it on this other head first and just duplicate it on the head for the 2.0.
Ok the intake springs being used on the exhaust side looks to be just the ticket. I've been trying a few combinations after removing the rotator and if I use the dimpled spring retainer it puts me just a bit on the high side of spring compression limits. The intakes are closer to bind but still ok.
I did need the break from this project, if I would have found out last week that the head had to come back off. I don't believe my reaction would have been very pleasant. I'm not overjoyed at the prospect but I have a renewed patience to keep at it.
I did need the break from this project, if I would have found out last week that the head had to come back off. I don't believe my reaction would have been very pleasant. I'm not overjoyed at the prospect but I have a renewed patience to keep at it.
All righty then, I'm in a POR kinda mood and I just got a good look at a few pieces that I really liked. I think It's running a little bit rich so I'll do the backwards thing and add cam before I mess with the jets.
I taped the motor so I can hear any differences after this upgrade and it was kinda nice working with a warm motor. Yes it's show time and the rollers are next on the to do list.
POR to me is Press On Regardless.
I taped the motor so I can hear any differences after this upgrade and it was kinda nice working with a warm motor. Yes it's show time and the rollers are next on the to do list.
POR to me is Press On Regardless.
Well the head has been off long enough. I replaced the questionable valve springs and adjusted and checked them all. Feeler guage in these pics are .020. I checked them all and set all the valves off of the motor.
I"m running in the cam as I type this. It just speaks volumes of ya never know what's under the hood. it looks pretty stock to me.....but I know better.
It gained 1000 RPM just upon fire up and after 20 minutes I toned it down to around 1100. It's running a bit hot but is cooling off, that was expected.
It gained 1000 RPM just upon fire up and after 20 minutes I toned it down to around 1100. It's running a bit hot but is cooling off, that was expected.
I was done letting it run in the new cam when my Dad came by. Yes I pulled the cover off just to show them off a bit. I don't think he got all that was involved but my daughter understands it all and likes the little purple bits on the car, she informed him of the purple upgrade.
Time to think about a clear cover for these.
Time to think about a clear cover for these.
1 - 20 of 65 Posts
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