To Boost - or not to Boost

    I'd check fuel pressure at the schrader valve when cold first thing in the morning. A leaking fuel injector, fuel fitting weak pump could all be a cause of it. After it restarts and stays good, keep a pressure gauge hooked up and see what the pressure reading is an hour, three hour etc later are. If it drops, you have a leak somewhere. If all looks good, the next time you go to start it COLD, cycle the key to on like you're going to start the engine, but don't. Turn the key off, wait a couple seconds and go through the process again. See if starting it this times keeps it running. It should be very easy to determine the issue.

    Good luck

    Nobody gets outta here ALIVE

    I would say it's in the tune. The one I have has 33,xxx on it, and it did it from the new install according to Brody (who I bought it from with 10,700 miles). Mine doesn't do it every time, in fact it's only perhaps one in ten or less in the summer. The cooler it is out, the more likely it will start up then stall. Mine has the early tune, and I just attributed it to trying to keep it lean as can and still be safe when not under boost. At idle, there are light popping sounds, again notorious of a lean idle. This hurts nothing, as long as it goes away as soon as you give throttle, which it does. I usually like to let it warm up a bit too, throttle is more fall on it's face until it's getting warm. Enriching the tune when cold would fix it, but I'd still not hit it until it's completely warm.... so really not an issue for me.

    I'm not fixing something that's not broken. I'm running with several other Slingshots, some with the tune, some without, and if we all drive the same I'll be within $1 of the same cost at the pump as they are. At times, I'll beat them getting better mileage than they do. But use the SC hard, that changes. With the MeanSling top on it at 85 on the interstate, MPG drops to 23 or less if headwind.

    I usually try to fill with 2 bars showing. I've ran it to the reserve flashing, but that still leave 2 gallons of fuel. When I'm down that low, I won't hit it hard or run curves hard. I just don't want the chance of the pump sucking air for a second, and the system going lean under boost.

    The vast of my experience with reciprocating engines is limited to years ago with carbureted engines. Knowing that an engine requires a little bit more fuel at cold start-up until it reaches proper operating temp. That's the purpose of a "choke". It enriches the fuel by either adding extra fuel or restricting air to achieve the enriched mix needed at start up. The extra fuel is only needed till the engine reaches proper operating temp and the fuel has better atomization. At this point I have had no issues with starting on my supercharger. Knowing that we changed the fuel injectors is there a chance an injector is misaligned in the fuel rail or an "O" ring got pinched?

    Quote from EricRedSL

    When I fill up more times than not, it will take 8gal+-. Lowest I've run is 9.2gal. I really don't worry about gasing it up. No issues to date.

    EricRedSL I do the same but the other day I was very low and headed to the gas station about a mile from my house. Pulled up to the stop sign at the main roar and there was a lot of traffic to wait on and I was on a up hill. The gas I had ran to the back of the tank I guess and I got the warning I was in trouble. The station was only two blocks away and I kept my speed up so I could coast into the pump if I had to. Never had to push a Slingshot and with my bad back I don't want to. Now I fill up way before that.

    If the music is to loud you are to old.

    My worst was when I did the Three Twisted Sisters here in Texas a couple years ago. Even though I was mostly full before starting, let's just say I didn't drive it to maximize the gas mileage. Literally ran out out gas as I turned into the gas station and had to coast the 50 or so feet to the pump.

    Quote from Goats_Hogs

    I would say it's in the tune. The one I have has 33,xxx on it, and it did it from the new install according to Brody (who I bought it from with 10,700 miles). Mine doesn't do it every time, in fact it's only perhaps one in ten or less in the summer. The cooler it is out, the more likely it will start up then stall. Mine has the early tune, and I just attributed it to trying to keep it lean as can and still be safe when not under boost. At idle, there are light popping sounds, again notorious of a lean idle. This hurts nothing, as long as it goes away as soon as you give throttle, which it does. I usually like to let it warm up a bit too, throttle is more fall on it's face until it's getting warm. Enriching the tune when cold would fix it, but I'd still not hit it until it's completely warm.... so really not an issue for me.

    I'm not fixing something that's not broken. I'm running with several other Slingshots, some with the tune, some without, and if we all drive the same I'll be within $1 of the same cost at the pump as they are. At times, I'll beat them getting better mileage than they do. But use the SC hard, that changes. With the MeanSling top on it at 85 on the interstate, MPG drops to 23 or less if headwind.

    I usually try to fill with 2 bars showing. I've ran it to the reserve flashing, but that still leave 2 gallons of fuel. When I'm down that low, I won't hit it hard or run curves hard. I just don't want the chance of the pump sucking air for a second, and the system going lean under boost.

    Yep It did it right after SC install. Glad you’re getting good use out of it! Still my favorite toy I ever bought. Looks a lot better with all the stuff you’ve done to it!

    I ordered the pfm exhaust. Looks exactly like the 1320. Bought from pfm because it was $360 free shipping. Anxious to get it installed. Supposed to be here 8/23. Once installed I want to drive it through a few tanks of gas to see if it affects mpg. Then I will order the 105mm pulley from Ddm.

    Quote from EricRedSL

    Anyone have a 105mm pulley and belt hanging around if you upgraded to a smaller pulley? $140 for a 105mm and then add $150 for a belt seems alittle up there.

    $140 for a pulley and $150 for a belt is pretty crazy, the pulleys from us are $110. We have the 100mm and the 105mm pulley on the site - https://www.ddmworks.com/Pulle…it-by-DDMWorks_p_789.html


    The belts are not on the site, but they typically run around $25-30, just give us a call and we can get you taken care of.

    I recommend to anyone buying a ddm supercharger to have a 2.5 exhaust and buy the 105mm pulley and belt. It's just allot easier to install these 2 upgrades from the get go. Of course you'll need a new header if you still have the stock header. I thought I'd stay with the 1320 header, cat delete and stock muffler. That lasted 3 months. Once you boost you want more! 😏

    Quote from EricRedSL

    I recommend to anyone buying a ddm supercharger to have a 2.5 exhaust and buy the 105mm pulley and belt. It's just allot easier to install these 2 upgrades from the get go. Of course you'll need a new header if you still have the stock header. I thought I'd stay with the 1320 header, cat delete and stock muffler. That lasted 3 months. Once you boost you want more! 😏

    I have all of those!!! I would also install the big brake kit!!!

    Always Remember...You can drive it like you want to drive it tomorrow! 8)

    :HEADERSS::SUPERCHARGERSS::COILOVERSS::ROTORSS:

    Quote from EricRedSL

    I recommend to anyone buying a ddm supercharger to have a 2.5 exhaust and buy the 105mm pulley and belt. It's just allot easier to install these 2 upgrades from the get go. Of course you'll need a new header if you still have the stock header. I thought I'd stay with the 1320 header, cat delete and stock muffler. That lasted 3 months. Once you boost you want more! 😏

    (best infomercial voice).....but wait there's more you can do! I have a 100mm pulley on mine now... really think I want the 95 and cam upgrade now when I have it out to do clutch anyway! Either way going to be a fun winter project!