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

Drive tune round 2: upped the secondary jets from 66 to 71. Wasn't going to start with that much initially, but I only have 1 each of 69 and 70 jets, so that's how that happened.....

Got out on a relatively empty straight away, slowed down to about 30 in 3rd gear and let it eat. Still seems to be a tad lean, kept in the 15s until I let off around 80mph. So I slowed down and tried it again with the same results.

As I was returning home I noticed my temperature gauge started rising. My initial thought was the fan connection as it was a tad loose when I was putting the manifold back together. I thought I had tightened it, but maybe it come undone? So I pulled over, temps still climbing, popped the hood and checked. It was still connected and the fan was blowing, but I was dumping coolant from the overflow. Since I was only about 2 miles from home I jumped back in and raced home. So now I have to investigate my cooling system again. It was fine last night on my initial drive in the dark, fine today on my first run, now it's puking coolant?!? Talk about pissing a guy off.....
 
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So I've been thinking of the coolant problem that come up. I have a Flow Cooler high flow water pump which requires the use of an anti-collapse spring in the lower radiator hose. I never had it until now and I know that the lower hose would collapse under hard acceleration, so I didn't really stomp on the go pedal very often. Now that I've installed the spring there isn't any kind of impedance to flow until it reaches the thermostat. So I deduced that that must be at least part of the problem. I also wonder if my radiator cap is still good since I've had it on my car for a number of years. It seems odd that it would let go NOW, but weirder things have happened. In any event, it's only rated at 13 PSI, so I wondered if the change in flow from adding the spring to the lower hose contributed to higher pressures. With that all in my mind, I went ahead and ordered a new high flow 180* thermostat and a new 16# radiator cap. They're supposed to arrive by the end of the week, so we'll see what happens once I get that all installed. I'm also going to take my secondary jets up a few more notches while I'm at it. Ideally, I think I'd like to get my A/F ratio back into the high 12s, low 13s when the secondaries are opened up. While not exactly a scientific approach, I think I'm going to jump them up to 76 since the 5 size jump the last go round took me about 1 full point toward that goal.
 
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Ok, what am I up to.... Round 3 I think?? :D

Looks like I took care of the coolant problem. Replaced the thermostat, which turned out to be a 160 high flow unit, and the radiator cap with a 180 high flow and a standard 15 pound cap. Rejetted the secondaries from 71 to 77 and went for a ride. Most importantly, the temperature never exceeded 180. And it's fairly warm today, 82 at the time I took it out. So that seems to be a win! :D When I had the opportunity to floor it and get into the secondaries for a bit, it would read lean then settle back into the 14s, so it looks like the jetting is at least pretty close but the squirter shot needs to be increased. I only have a handful of them in my box-o-parts, so I'll have to see what I have.....
 
Just swapped squirters. It had a 25 in the secondary side and of the 3 spares I have, only one is a different number. It's a 32, so I installed that. We'll see what kind of difference that makes. :shrug:
 
Next go round - installed the 32 squirter like I said. Tried to record the drive again, but as was the case last time, it just didn't work out. It would be most helpful if I could though, then I could look at everything - RPMS, A/F gauge, etc. BUT, it still reads lean until the RPMs are up there, then it's back into the 14s. Not real sure if I want to increase the jet sizes again or if the secondary squirter need a little more attention. I did double check it before I left and it's shooting fuel the instant the secondaries open, so there's no delay. But with what I have for parts laying around I can't really do much more than jet sizes, so I think I'm just gonna call it good for a while. The only other thing I can think to do would be replace the secondary metering block with a primary, that way I'd have 4 corner idle adjustment, just not sure I wanna fiddle with that. :shrug: But I know that if I added the idle adjustments to the secondaries I'd be able to richen the mixture all around when the secondaries open up. Decisions decisions....
 
Oh, and a pic from just after I parked it and just before I shut it down. Notice the temp gauge is right around 180.... :D

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@2Blue2 - You'll be happy to see that a certain Cobra went for a joyride tonight. :D

It's running REALLY well!! Temps fluctuated between 170ish and 180ish and the A/F stayed between 12.8 -14.5 pretty much the whole time I had it out, which was about an hour and a half or so. Even took the dog since the car isn't as loud as it was. Turned a corner in a hurry and probably put the accelerator down about halfway and fishtailed for a second too. Don't worry, there will be NO Mustang fail video with MY car!! :rlaugh:Since the dog was with me I didn't get too out of hand and drove fairly normal otherwise. It was good to just get out and stretch it's legs!!

Tried to record the drive again - looks like I'm going to need some other way to mount a camera, what I have just isn't cutting it.....

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You forgot one thing: the accelerator pump cam. The amount of fuel that is added if accelerating is defined by the stroke of the pump cam. The squirter is more for the duration of the "injection". How does your primary side look? I think the primary will be allright, because you don't have a bucking if you put the pedal down, right? Then I would care (as you did) about the secondary side. I would keep the 32er squirter but I would use a bigger pump cam (e.g. pink in position 1).
In general it should be tuned like this:
primary needs to be mid to big squirter and low to mid pump cam, means mid amount of fuel very fast (that the car has enough fuel till the jets react). On the secondary you need is vise-versa: big amount of fuel and long duration.
If you have the bigger pump cam tested, you still can go down to 28 squirter if it doesn't work.
4 corner idle is for idle not for lean mixture at acceleration ;)
If tuning the accelerator pump cam, i would test based on feeling. the AFR (or the digital reading) often react to slow to get a good reading.
If the AFR stays about 5 seconds after putting the pedal down still in the 14s, I would step up the secondary jet size. But if you think about tuning it on the dyno (as you once said) I would prefer to make it on the dyno. On the street it is difficult to stay legal while testing :nono::jester::rock:
 
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You forgot one thing: the accelerator pump cam. The amount of fuel that is added if accelerating is defined by the stroke of the pump cam. The squirter is more for the duration of the "injection". How does your primary side look? I think the primary will be allright, because you don't have a bucking if you put the pedal down, right? Then I would care (as you did) about the secondary side. I would keep the 32er squirter but I would use a bigger pump cam (e.g. pink in position 1).
In general it should be tuned like this:
primary needs to be mid to big squirter and low to mid pump cam, means mid amount of fuel very fast (that the car has enough fuel till the jets react). On the secondary you need is vise-versa: big amount of fuel and long duration.
If you have the bigger pump cam tested, you still can go down to 28 squirter if it doesn't work.
4 corner idle is for idle not for lean mixture at acceleration ;)
If tuning the accelerator pump cam, i would test based on feeling. the AFR (or the digital reading) often react to slow to get a good reading.
If the AFR stays about 5 seconds after putting the pedal down still in the 14s, I would step up the secondary jet size. But if you think about tuning it on the dyno (as you once said) I would prefer to make it on the dyno. On the street it is difficult to stay legal while testing :nono::jester::rock:

Thanks! I guess I didn't really mention the secondary accelerator pump, did I? That also crossed my mind, but again it's something I'd have to order and not something I have on hand. I really wish I could get a video recorded the way I want, it would help much more than what I can convey through text. It has no bogs at all, which is great! And it stays lean for a bit, it's not just a for few seconds. But yes, I did think of the 50cc pump in conjunction with squirter size. I might try to go with that at a later date in conjunction with testing different squirters. Both that and a cam assortment, which is another thing I don't have on hand. :shrug:

And it's only illegal if you get caught! :banana:
 
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Tis fine gage pod/hood cam!

Glad your driving it:):cool:

Kind of wish gage would flash left to right instead, but fun to see, good stuff
 
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Quick update: I received a new 50cc accelerator pump yesterday and have that installed now. I went ahead and upped the secondary jets from 77 to 83 while I had the fuel bowl removed. I've left the squirter alone for now. Time for a drive to see what all of that does for me.
 
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Just got back from a quick run with it. It seems to be a LOT better. I only really had one opportunity to open it up though. It read lean for a split second then settled back into the 13s. At idle and once warmed up I noticed that it's reading lean at idle now, I'd say averaging around the 17s, but under cruise it's still in the 13s dipping into the 12s occasionally. It is a little warmer today at 86, but I wouldn't think a couple degrees would affect it that much. Maybe I'll try to get it out later this evening and give it a go again and try to keep a good eye on those numbers. Again, it would be AWESOME if I could get it recorded.... :nonono:
 
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Today's test drive round 2: turned the idle mixture screws out about 1/4 turn to bring my idle mixture back to 13.5 - 14.x. Got out on my test road, 3rd gear @2000 RPM and floored it. It dropped lean for a second or so, into the 17s and 18s, then settled back in around 13.5-14.x again while still accelerating. No bogs, no hesitation, just lean for a second. I may need to order a secondary cam kit to get that ironed out and maybe a bigger squirter, otherwise I think it's pretty damned good. Now I'm itching for another dyno day to see what the changes have done and compare to last year. :D
 
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At idle and also directly at acceleration the AFR reading can be unreliable. Can you tell which pump cams (color) you have installed on primary and secondary side? Some of them have two positions, perhaps you can tune it with what you already have.
If your going to the dyno anyway, I perhaps would leave it as it is and ask them on their opinion. As you said no bogs and no hesitation is the most important part.
 
The 50cc pump only came with one cam with one hole. I ended up installing it in the #2 position on the shaft as in the #1 position the actuator lever had to be adjusted so tight that it collapsed the spring. As far as any more adjustments go, I don't plan on making any more at this time. It's running really well as it is and even if it's running lean at WOT for a second or so then leveling back to where I'm comfortable I think it's good. I mean I don't go WOT all THAT often. And like you said, I'll see what the dyno says if/when I get it on one again.
 
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