EFI blower conversion done - Off for a Dyno tune now!

Hope you aren't discouraged. First time Dyno is like First time at the drags. Unless you've weeded out all the problems and done the initial tuning yourself, it always seems disapointing. You'll get there, although you may need to *encourage* your tuner.
I agree with Red65. Check the plug gap. What's your air-fuel ratio like?
Any way you can post your charts?
That air filter should flow just fine. For a test you can always pull it off while on the dyno. Might need a piece of screen to smooth the flow to the MAF during that test though.
Bar-stool QB here, but I'm making a little over 390-390 with no tune and 24lbs injectors, a 73mm C&L MAF, and a 65mm TB on a Ford 340HP crate with a stock Vortech S trim Fox kit, and a Cobra intake.
I *think* they need to work a little harder to help you out.
Your 165s flow better than my X304 heads, and you are running more total CFM, even though the pressures are the same as mine. You should be up on Red65 territory.
Might want to read up on the supercharger forum, or one of the "Tweecer" forums so you can *converse* with your tuner.
Good luck man! I'm really looking forward to hear how your cars runs when it's all sorted out.

Scott
 
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That is the first thing he was going to do after the pulley arrives. I set the gaps at 35 but it looks like that was too wide. I will relay the info to him but it looks like he has things under control.
If I think that can be a cause, I get on the extreme side. Gap to like .023, if it gets better, then you know what it is even if you don't really need a gap that small.
Could also be valve float, but less likely the culprit if you don't have a box. The boost tries to hold the valve open, so it is possible, but highly unlikely. 12psi here with OLD AFR springs. So far so good.
 
Are you saying if I had a box the spark plugs would likely still be firing at the .035 gap and then the problem would be valve float?

You'd have a much etter chance f gettng it to fir. But that's bordrline I would think. What I suggesting is if you go to the extreme, and close the gap down,an it gets better, you'll now what it is.If it misses @ 5k, and you re-gap and it misses & 5800, you know it's spark. I would really look at it if i were you. If you are running stock EFI you don't want to hit the factory limiter an have it drop fuel @ WOT.
Now, if you gap dwn OR put on a box, and nothing changes, then you culd be looking at valve float. There are ther factors also, like your ALt. If it in't up to it, the spark can blown out from that also. Hook it up to battery charger for one pull to find that out.
 
Thanks for the help! I don't have a dyno sheet for the car yet. Heck, I haven't even heard it running yet. The tuner said it was running pretty rich. I think he said it was about 10.9:1 :shrug: (sound about right?). Is it even worth it to buy a MSD 6AL box for this type of application? Would it help burn some of the extra fuel and therefore increase the HP? I ran one on a 66 I had about 10 years ago and I didn't even notice a difference. After I sold the 66 I sold the 6AL box I had on Ebay for about $95. Back in the day they were about $160 and now they are about $240. Don't you just love inflation.

Sorry for all the questions guys. I just want to have a better understanding when the tuner talks to me and spend my money where it will be a benefit.
 
Is it even worth it to buy a MSD 6AL box for this type of application? Would it help burn some of the extra fuel and therefore increase the HP?

I ran my car hard for two years (mostly open-track and HDPE, meaning that it experienced extended WOT - more than drag racing) with the stock ignition kept in good shape. Once I set the plug gaps, I never had a problem with it again. I don't know if the MSD box will allow you to run larger plug gaps, but I see no down-side to setting them a bit smaller, as 10secgoal suggested, and seeing if it improves. You'll know right away on the butt-dyno if you've solved the problem or not.

10.9 is on the rich side; your tuner should be able to lean it out a bit - low to mid 11's - and still have a very safe tune (then again, he should already know that).

For what it's worth, my initial dyno numbers, before I figured out the plug gaps, were in the 300s - you probably just have to get this problem figured out to pop up into the 400 club. Good luck - don't give up. It'll be worth it when you realize you can break the tires free in third gear at highway speed and the perma-smile sets in.

- Andy
 
10.9 is pretty rich. As more and more air gets crammed into a motor it becomes harder for the spark to jump the gap at the plug. It needs more energy to do so, or a smaller gap. Running that rich won't help at all. You may see the miss go away as the AFR leans out.
 
Well I went over today to look at the car and saw the dyno run from last week. It looked like a pretty steady climb in hp until about 4000 rpm and then fell off the chart. I guess that is when they were having spark issues. It was putting out a little over 300 hp at that point. The torque curve also lost momentum at the same point. It was a consistent 350ish and slowly climbing until that time. I should have a pulley and MSD box by the end of the week. At that time I will get a final tune.

I would love to have 400 hp but it doesn't look like that will happen. I would be please with the 370 most of you are saying. I will update you at the end of the week, I hope, on this experience.
 
At 4K rpm, you are just getting into boost. There should be plenty more left with that combo. Injector slopes, breakpoints, Maf slopes, timing curves, it all starts making a big difference. So once the mechanicals are out of the way, I am sincerely hoping you are blown away... no pun intended.
Not trying to pump you up, but, I'm going to be disapointed if you aren't above 400 on both sides of the scale. I personally think your combination is worthy of those numbers.
Good luck, and my fingers are crossed for you. Darned hard to type this way, so hurry up!
 
Thanks for the words or encouragement Scott. By the way, did you end up finding your Mustang? Sorry if I missed the update on this one.

On a side note. Do any of you guys with boosted applications have problems with oil coming out the breather? I know my system has a hose connected from the breather tube to a hose barb on the filter cover. I just don't want oil pissing all over my engine compartment. I am thinking of putting on an oil breather tank to fully eliminate this possibility.
 
That fitting shouldn't be an outlet, unless you have excessive blow-by like Bosscat was saying. You do want a filter on it though. It's really the clean air intake for the crankcase, so that your PCV will work correctly.
I haven't looked at the car since I got it back after it was stolen, but with the rev limiter, I doubt there are any issues. I've haven't had a hint of oil at the filter or the barbed fitting.
My buddies running a deep breathing 331 with about 8psi boost, and his is clean and dry as well.
 
I appreciate the responses guys. I got the MSD box today and the pulley also arrived. With any luck they will be done with this thing tomorrow, I hope. I hope to get a copy of the dyno run and I will post it on here for you all to see. Next stop will be the body shop for a nice coat of HOK Kandy Brandywine over Gold. :D This whole project is starting to come together. I can't wait to drive the car. It has been almost 4 years and I have only clocked about 20 miles on the odometer and that was when it was a 6 cyl car. I think it should feel a little different now. Don't you agree? :banana:
 
Yeah Baby!

That's a great start! Man, you just made my evening! So now my G.F. is going to be wondering why I have a Cheshires cat grin at dinner tonight.
Right on man!