Got car to the track this weekend- not very impressive times

Thanks again for everyone's help! I will look at getting some good plugs and making sure the gap is set correclty- I have been reading and should I upgrade the coil inside the HEI with a GM performance or upgraded Petronix (provided the one in there isn't- I would almost bet the coil has been upgraded- almost everything on the car has been).

Plugs in the car are NGK Platinum we believe. They should be a good plug, right? Wires are 8mm Taylor and are in great shape. I have never used NGK plugs before (I have always preferred a Champion plug) but they have a solid reputation. Problem is they just say NGK on them with a big letter R and looking online so do a lot of thier plugs...

Car was running on 87 regular unleaded (EEEK!) when I got it- part of the reason it was sold was the guy couldn't get it tuned right. I think a lot of his problem was the gas he was running. E85 is available a lot of places by me- is there anything I need to do (other than adjust the tune) to run it? We have gotten the tune a lot closer than it was, I would almost hate to start over on E85 this close to putting it away for the winter. Since I bought the car it has had nothing but 93 octane, and I always try to use Shell/BP gasoline. The car I sold to buy this one was a Corvette and it was very picky about what fuel it used- there is a noticable difference between some of the smaller no name gas stations and BP/Shell (or other national chains).

The reason I want to go with a boost controller/external wastegates is so I can better control boost creep- 10 PSI is fine for this engine, but I want to know the boost will stay where I set it. If I want 10 PSI fine, but I don't want 8 PSI creeping to 10 or 12 during a 1/4 mile sprint. I will probably just start out with a manual boost controller- no need for a fancy electronic boost controller for my purposes.

I too believe there is an 11 second car hiding under the bronze paint- I just have to find it.

Next steps are: New exhaust header gaskets - new valve covers (got a set on trade - the ones on the engine are ugly painted chrome with all the paint flaking off) - then head to the track this weekend for TNT time to try and get the bogging at WOT figured out.

Need to check the timing too- never checked to see what timing (initial or vac advance total) this motor has. That could be part of the initial accelleration issue, could it not?

Cheers!

~K

 

First off here is my disclaimer. If you can not afford to set up the LM-1 for data logging, and upgrade your fuel system then just park the car till you have the money. Please do not kill this turbo car due to lack of fuel system or not knowing your air fuel ratio.

Like others are saying get a colder plug and gap it nice and tight, otherwise you are wasting your time tuning.

You can datalog the info from your LM-1 but you really should have the tach and throttle position sensor hooded to the LM-1 for get the best data. Then you can see what RPM and throttle position resulted in what air fuel ratio/
I would avoid the E85 fuel and stick with the high octane premium fuel. There are a bunch of mods needed to run E85 and your fuel system is too small already and using E85 would make things worse. It takes about 25% more E-85 fuel vs normal fuel so you would need a much better fuel system.

Yes, you should look at the timing. This is more important than carb settings. I would set it at 28 degrees total timing if you are keeping the boost low. If you want to crank the boost up which I would do then use about 26 degrees total timing or use a MSD box with a retard set at .5 degree retard per pound of boost and then use 32 degrees total.

Instead of buying a controller just turn the boost up to 12 PSI and you should have no boost creep. I would not be scared to bump the boost to 14 PSI even but thats just me. Buy a good fuel system and you should be in good shape.

 

Not sure my fuel lines are any limiting factor at the moment- I want to run bigger lines mostly as I want to run a much more built engine in the future (plan on building complete forged bottom end and 22 PSI in the next year or two - also a pair of much bigger turbos.
At the power levels the current setup will produce (possibly 600 HP and that is pretty optomistic) I believe the factory lines will provide plenty of fuel. Fuel pump and boost referenced regulator are high quality parts (I forget the brand but the fuel pump itself is $350 and the boost regulator is another $150). I am actually running too rich at the moment- so lack of fuel is not a problem. I believe my exhaust leak is making the wideband see it as leaner than it actually is so when we got the AFRs into the "right" spot we are actually way too rich and bogging it down. I did run it for a bit today and tried to hear if there was any leak on the passenger side- I believe there is a small one.

Data logging would be nice but not really needed to tune the car- I did find plans online on how to build your own TPS from Radio Shack parts. I have also been reading a lot about the megasquirt controllers and will have to look more into that for the future, but for now I want to get this QF carb running like it should.

Cheers!

 

OK so I think next paycheck I am going to do the TPS- I found Innovate makes one that will go right into the MTX-L and bolt right onto the QF 750- and it only costs $69. My next question is how to capture the RPM? Is there something that I can buy or make that will convert the MSD 6AL green wire output into 0-5V DC that the Innovate can use?

I suppose I should put my voltmeter on the green wire and see what output it is already giving- then figure out a resistor or what would be needed to convert that signal to 0-5V...

I am a computer geek by trade so already have a couple laptops with serial ports I can use to log

 

The MSD Gray wire (it looks like green) tach output signal has a 12 volt, 22 -25% duty cycle so a voltmeter won't read the peak voltage.
you would need an oscilloscope to see the signal.

You can clip the peak by using a 1K resistor and a 5.1 volt zener diode. 1N4733A, Radio shack Catalog #: 276-565.

What device does the tach signal feed into?


Paul

 

LogWorks software came with the WideBand and has pin inputs for three additional sensors (in this case- TPS and tach).

So that is the greenest gray wire I have ever seen- on my MSD 6AL it is a forest green I am pretty sure- it currently goes to the tach on the dash, would it cause problems to split that wire off and send it to the data logger after doing the resistor/diode?

The Logworks software will be running on an old laptop (I have to see if I have a 9" laptop with serial port on it- I doubt it) running XP

The Logworks requires the signal to be 0-5V and you define what input you are giving it (O2/tach/TPS/EGT, ect...)

 

No problem splitting off from the tach wire.
What model number MSD 6AL do you have. All the MSD ignitions I've ever used had a gray tach wire.

Paul
.

 

I can check on the MSD model number (I know it is a 6AL)- the tach wire could very well be a replacement- it connects to the side of the MSD box via a male space connector via the tach output and is not hard wired into the MSD box.

I do know it is a dark forest green color, but come to think of it I believe it is the wire that comes from the back of the Sunpro super tach II (I replaced this tach right after I got the car and pretty sure when I replaced it I put on a spade connector to replace the one from the old tach that was setup the same way).

I may just to the easy way and buy this:

http://www.amazon.com/gp/product/B001S7NEB6/ref=ox_sc_act_title_1?ie=UTF8&smid=ATVPDKIKX0DER

It has inputs for a direct tach wire as well as the terminals for three more connections. I can order that box and it will data log for 1.5 hours and then dump everything to a laptop. Is only $100 and it should work right out of the box without gueswork, and I will not have to keep a laptop in my car during runs.

$170 for the logger and tps- not too bad.

Thanks again for your help Paul!

~Kevin

 

Kevin

Looks like a great little unit especially for $100.

A whole lot less :dollar: than the Racepak equipment we use.

Paul

 

I figure for the price it will be hard to go wrong- used ones are going for $75 so if I end up moving to a better unit when cash isn't so tight then I can resell and get most of my $$ back, however if it does what I want (and has inputs for two more sensors- I am thinking boost and ??? in the future) then why upgrade? I would rather spend the money on a forged bottom end so I can go more boost and not worry. The ZZ4 motor then then get swapped into my Jeep.
My SBC Jeep currently has a junkyard 80s truck motor in it that is unknown miles (still runs good).

My exhaust gaskets will not be here in time for wrenching this weekend so I think I am going to get a set of Autozone cheap ones to install so I can get them installed Sunday (only day I have to work on it this week). I am out of town most of next week (VEGAS BABY!). I want to have the exhaust done before Sunday next week - TNT at the track.

I have an 1/8 mile at work I can run on (as long as we are closed) so hopefully Sunday we can get it running right.