14point7 Spartan 2 install, Holley 4150 tuning, & exhaustcapades

  • Sponsors (?)


Round 2: Took the carburetor off and installed the 6.5 power valve. Confirmed it's operation the same as before. Messed with the idle mixture screws again and ended up about 1/4 turn out, 14 in vacuum, idle about 750, a/f jumping between 14-16. Kept fiddling with the mixture screws just a slight turn at a time until I ended up bouncing between the high 13s to the low 15s. Gonna call it good right there until I get it out on the road. I'll play with jetting at that point.
 
  • Like
Reactions: 1 user
I messed with the mixture screws a little bit more after my last post and ended up with the following. NOW I'm calling it good. Slightly rich, but not too bad....


View: https://youtu.be/2qeyYYjt01Y



And, as you may notice in the video, I think that temperature gauge is now toast. The radiator cap read around 200 degrees at this time. Gonna have to look into replacing that now too....
 
  • Like
Reactions: 1 user
I had to search online for my cam specs, I couldn't remember which part number it was anymore. It's a Melling part number 24203, here are the specs. Posting here so I won't have to search for it anymore AND to confirm the LSA as I misspoke earlier.

Adv. Intake Duration288
Adv. Exhaust Duration300
Intake Duration @.050214
Exhaust Duration @.050224
Intake Valve Lift w/1.6 Rocker Ratio [w/1.72].473 [.508]
Exhaust Valve Lift w/1.6 Rocker Ratio [w/1.72].497 [.534]
Lobe Separation Angle112
Cam TypeHydraulic Flat Tappet
Basic Operating Range2800 RPM
 
the reading of the O2-sensor is at idle not the best, because of the low gas flow. The best method is to check the vacuum. Tune it for max vacuum and the you can make it a bit richer.
I would still check the ignition first, after tuning of the ignition and jets you need to readjust the idle again.
 
So far in my attempts I had 15 inches of vacuum, so that was as good as it got at that time. I can tinker with it when I go back out there, probably this weekend. And I'll try to remember to grab the timing light since I failed to do so this time around. I guess I was too excited that I was going to play with a new toy. :D

But I ordered a bunch of new gaskets and a new set of temperature and oil pressure gauges this morning, so I'll have plenty to keep me busy. I've changed the oil pan gasket in the car before - it's not a whole lot of fun, but it IS doable. It's times like these I wish I had a lift....
 
  • Like
Reactions: 1 user
Speaking of lifts: https://atlanta.craigslist.org/nat/tls/d/lawrenceville-maxjack-6000-lbs-two-post/7114062819.html

00c0c_9UlYWIOPrh7_1200x900.jpg


I kinda wish I was in the market for a lift right now. If I were I'd most likely jump on it at that price.
 
  • Like
Reactions: 1 users
I'm expecting the new gauges and pan filter today, so I didn't start it to get initial timing. I ended up removing the existing gauges and will wait until this weekend to really dig into this. It's supposed to rain today and I'm out in the elements, so I'm not going to go too deep. But I did pull the distributor cap to verify the mechanical advance as best I could. The springs are blue, which according to MSD's instructions are 2nd lightest. I tried to look at the bushing stop, but it's pretty hard to tell whether it's blue or black. In either case, the advance looks to be all in around 3k RPMS and is a total of around 20 deg
Screenshot_20200429-125328__01.jpg


Screenshot_20200429-125353__01.jpg


IMG_20200429_115749.jpg


If you've ever messed with the stop bushing in one of these distributors you'll know how much of a PITA it is. In this pic, it's under the innermost pin that the spring on the right is attached to. So, to confirm exactly what I have, I remove the nut from underneath to be able to remove the bushing. Once I get it out I'm able to confirm, without a doubt, that it's blue.

IMG_20200429_122104.jpg
IMG_20200429_123021.jpg


Now I know what the ignition curve is. 21 degrees total advance at around 3kRPMs. Way back when, when I installed all of this, I played with the different springs and bushings and found that this setup worked the best. I saved the others, but as with the Holley book, they've disappeared somewhere. Only with this I'll make a more educated guess and say that it was lost or misplaced in a move at some point. So if I think I need another I'll have to order one.
 
  • Like
Reactions: 1 user
Ok, slight snag on the timing confirmation..... I think I might have the wrong pointer. :nonono: I climbed under the car, cleaned up the timing marks on the damper, fired the car up and hit the timing light. Remember when I said it was timed at TDC? Come to find out the timing was set at 14 degrees - AFTER TDC???? I tried taking it beyond TDC going the other way and the car just doesn' t like it. So now I'll order a timing tape and will be doing that, probably next weekend. :mad:

On a positive note, I got the new gauges installed in the gauge pod..... :shrug: And my A/F ratio read where I set it before...... :nice: Oh, and I can rent the drywall jack for the bedroom project, so I'll be working on that the rest of the weekend. :banana:
 
Last edited:
Sounds like your car will run awesome, when you are finished... :D

Man, I hope so!! Lol
All these little things I THOUGHT I had a handle on before (except the carburetor....) popping up are a good reminder of just how much you DON'T know. Or at least overlooked and/or forgotten for one reason or another. Thanks for pointing me in the direction that led me to this point! It obviously needed to be done.
 
  • Like
Reactions: 1 user
On anything with a decent cam and compression and good fuel I usually aim for all advance in by 2500 rpm. Looks like by your chart your advance is all in by 2800 to 3000 so thats close. What is the chart like for one blue one silver spring?
 
  • Like
Reactions: 1 user
Screenshot_20200503-163749.jpg


Here is the complete list of charts for the available advance curves. If I can find the rest of the kit, since I KNOW I didn't throw it out, I can play with the different settings again. But it looks like with the blue bushing and a blue and light silver spring it would be all in around 2500.

I haven't messed with the car at all the rest of the weekend though. I spent all day Saturday hanging drywall for the ceiling for the master bedroom project I've been working on. That throroughly kicked my ass as I'm feeling it today.
 
  • Like
Reactions: 1 user
Oh, it's all the time. And it's because I have dumps, but I really have nowhere to route a tailpipe with a Fox fuel tank. I've toyed with the idea of adding short glass packs but wonder how it would affect the tone. I know they'd help quiet it down though, just never jumped in. I mean I like how it sounds, just not the volume, especially on longer drives. I don't mind it so much on short drives. It's easy to drop the exhaust if anyone didn't notice, that might be my next mini-project.
Take a look at ElSuperPinto's exhaust in my thread. That was my solution to end the headache of running dumps.

I'm going to revise it by replacing the 90 degree bends with 120s to put the tips closer to the rear tires instead of at the doors, but beyond that it works perfectly, no more booming in the cabin.
 
  • Like
Reactions: 1 user
I'm pretty much the same. When I got my car running again in the mid-2000s I played with the springs and bushings and ended up with what I have now. Then when I took the heads off and gave it a refresh around the time I was in my accident in 2015 I set the timing to what it is now. I either didn't think or don't remember that I was setting the timing AFTER top dead center as I noticed recently. So now it's become a quest to get it done properly and so that I KNOW what it's set at. I may bite the bullet and go ahead and order a new advance adjustment kit and play with the timing again, but I think I'm going to hold off on that for now. First things first, I'm going to make sure my initial timing is set, change these leaking gaskets, and continue adjusting the carburetor.

I grabbed my 12" calipers and measured my damper, it measured a few thousandths shy of 6-1/2 inches. The available timing tapes go from 6-3/8" to 6-3/4". The best option would be 6-3/8", but it will give you a false reading. In my mind anyway, that wouldn't be much better than timing it by ear, which is essentially what I had before. SO, in an attempt to search for an ACTUAL tape for a 6-1/2" diameter balancer I found a website that you can print a tape for about any size you like, so I'm going to give that a try. If it doesn't work I'll resort to buying a 6-3/8 and go from there. I figure this way I'm really not out anything but time....

 
Take a look at ElSuperPinto's exhaust in my thread. That was my solution to end the headache of running dumps.

I'm going to revise it by replacing the 90 degree bends with 120s to put the tips closer to the rear tires instead of at the doors, but beyond that it works perfectly, no more booming in the cabin.

I have thought about taking it to an exhaust shop and see if they couldn't bend some pipe over the axle and have them exit right after the rear wheels, kind of like what I remember the mid seventies Camaros and Firebirds had. I may give that a shot at some point, but I know that either approach would help with the volume in the car.
 
  • Like
Reactions: 1 user
The problem would be finding someone with a mandrel bender. I can't imagine many shops having one, I'd think that most would just have the other. :shrug:
 
The problem would be finding someone with a mandrel bender. I can't imagine many shops having one, I'd think that most would just have the other. :shrug:
Hence why I run the setup I run and advocate the hell out of it. When I do the 120 degree bends, I'm also planning on some Trans-Am style tips laying sideways, giving me dual exits right in front of each tire tucked up to the pinch weld (with the plan to eventually put some side skirts on it).
 
  • Like
Reactions: 1 users