Race Gas? How Much Improvement?

[BRAD_PADGETT]

I have an 85 GN and was thinking about going to our local Buick club's drag race this Sunday. What will race gas give me in performance? These are my mods- 30 ibs injectors, cold air kit, Poston headers, Hooker hi-flow exhaust, test pipe, Casper Ultra chip( adjusts for octane), hot wire kit(new GM fuel pump), turbo set to max at 20ibs boost(It makes 20Ibs), 160 thermostat and frame brace kits all around. Any input would be helpful. Thanks- Brad

 

[1QUICK85]

I still dont understand how you run 20# of boost without race gas or alky?? Race gas is used to turn boost up around 20#, but if you running 20# of boost on 93 octane then you don't need race gas

 

[BRAD_PADGETT]

Thanks for the help. I get 20 ibs boost with my adjustable waste gate actuator. I could get more but I told my mechanic to limit it there. Brad

 

[1QUICK85]

Do you run just straight 93 octane?? Cause everyone on this website with an adjustable wastegate rod and 93 octane cannot run 20# of boost without knock problems unless its 30 degrees outside. Are you getting any knock? What do you use to watch knock? Do you have a knock gauge? Is this the stock boost gauge or an aftermarket one?

 

[BRAD_PADGETT]

I run straight 93 octane. The 20 ibs boost rating depends on the wheather and how hard I punch it. I just dropped my son off and did run two tests odf the boost tonight. It is 45 degress here in northern Illinois and I got two 18ibs max boost ratings. I do not have any knock nor any way to measure it. The 85GN is stock except for-30ibs injectors, hot wire kit, Poston headers, Hooker hi flow exhaust, test pipe, cold air kit, adj. waste gate from Poston( can be set higher), 160 degree thermostat, and a Casper utltra chip for my stock ECM set to number three(92 octane)-which changes the spark timing from 22 degrees to 18 degrees at W.O.T. It also has settings for 93 octane as well as race gas 98,110,and 113 octanes. I also have a mystery block from Jasper which my have modified cylinder heads. My mechanic and I don't know but that is another story. Thanks- Brad-

P.S. Race gas is used to reduce knock-Right?

 

[BRAD_PADGETT]

I forgot- I put on a new VDO boost gauge after I blew up my old motor with a stocker boost gauge and a new adj. waste gate act.
Brad

 

[1QUICK85]

If you have no way to measure knock then I would not be running around with the wastegate rod adjusted so that its capable to hit 20# of boost. Just dangerous. Race gas allows you to run more boost without knock. It was 45 degrees today in WI and I was fooling with my car and hit 20# of boost on accident and I got knock. Scared me sh!tless. There is no way I would be running that amount of boost without racegas and without a knock gauge on purpose!!! If you can't measure knock, thus no knock gauge, then how do you know you getting no knock? I would definatly get a knock gauge and adj. fuel pressure regulater and fuel pressure gauge!! And when it starts warming up outside you better turn your boost down a little. I am just affraid your running around at 20# max doing damage to your engine and you dont know it yet!!! Got to have the right gauges or scan tool so you don't blow up your car!! Please get a knock gauge to go with that boost gauge. On days when the weather is hotter outside or you get some bad gas(does happen) you may have to turn your boost down......a knock gauge is awesome at telling you this! Nick

 

[Jerryl]

Brad,

I have a Casper knock gage installed and have an OTC 4000 monitor. Here are a few things I noticed. Note that there are tolerances in these electronic parts, so the observations apply to “my gauge readings”.
· The Casper knock gage gives pretty much instant response to knock. I.e, when you hear knock (YES, I can hear it when it is BAD, but I was only running 5-7 PSI boost), the gauge responds within 0.5 sec.
· The OTC monitor shows KR after the Casper gauge goes off at a around a 1 sec delay.
· The first green light on my gage comes on around 1-3 KR and the second around 4-7. The orange light corresponds to 12-17 KR. (NO I did not blow a HG)
· I can hear knock when the orange light goes off, not when the green lights go off.
· Note that the car has a quiet exhaust system my audiograms are fine.

Point I am trying to make is this.
There can have around 7-12 KR that you may NEVER hear and will need a way to monitor/watch your knock. You have spend too much “blood sweat and tears” on that motor not to do this. If your mechanic tells you that all is well running 20PSI without a monitor knock, I would advice a different one.

A ASME Certified mechanic may be able to put the parts together but know nothing about these cars and even less in how to tune them. This is the reason why we study this board and some do the work ourselves. Just my $0.02

 

[BRAD_PADGETT]

Jerryl and Nick- Thanks- for the advice. I have to admit that I am a clueless idiot when it comes to knock. I probably have knock and do not even know it. The car runs great and I want to keep it that way.

What is the stock max boost setting? I am thinking of adjusting the waste gate actuator down to the the stock setting. Will this keep me out of knock trouble? I also saw a knock gauge in the Poston catalog - are knock gauges hard to install? In the mean time I will never go over 8ibs boost until I get this situation under control. Thank-you- You saved me from blowing up my engine. Brad

P.S. Thank god I posted this. I was thinking of going to the drag strip for the first time today with the local Buick club. That idea is out the window!

 

[Jerryl]

Brad,
Just trying to return some “advice favors”.

The Poston gauge is the same as the Caspers. Caspers makes all the TR knock gauges.
Gauge is easy to install. You will need to run wires form the computer and basically “T” into the specified wire at the ECM. Pretty straight forward.

Stock setting for a HA is around 12 PSI as gathered from my readings. Differs from car to car and too many other variables. Besides, the gas is different now then it was in the mid 80's. The gas today is also different in different parts of the country at different times (Summer vs winter), so hard to really say what “stock boost” will work for you. I have never seen 10 without knock but I KNOW that there are issues with my set-up.

With the gage, you will know when you get knock before destroying that new motor in the event you ever pay for 93 but really get 89, or the temp/humidity changes, etc. You may even notice that some gas stations have better gas then others.

May be interesting for you to run the car with the knock gage, or, find someone with a scan tool and see if/how much knock you are seeing with your current set-up at the current boost level. You will then know if it was worth the price of the gauge.

 

[BRAD_PADGETT]

Jerryl- I will order the gauge tommorow and install it with my current set-up. I will update this thread when I test the car with the new gauge. Thanks- Brad

 

[Bryan C.]

Brad - Where were you today, we had a fun day of racing.

 

[BRAD_PADGETT]

Bryan- You must have gotten a kick out of my thread! This cluelss idiot has been driving my car around with the boost set too high! I found this out yesterday morning and needless to say I cannot get into the turbo until I get a knock gauge(ordered today) and set the waste gate actuator correctly. Fortunately I do not push the car very much because I probably have knock and don't know it. The responses scared me to death. I probably woukd have blown up the motor had I drag raced the car yesterday. What do you think the responses tho this thread and the my ioiotic setup on my car? You cannot hurt my feeling at all. Thanks- Brad

 

[BRAD_PADGETT]

I now have a Caspers knock gauge which I will install this weekend. I will test it in the next few days. Brad

 

[cool 84]

Originally posted by Jerryl
Brad,

I have a Casper knock gage installed and have an OTC 4000 monitor. Here are a few things I noticed. Note that there are tolerances in these electronic parts, so the observations apply to “my gauge readings”.
· The Casper knock gage gives pretty much instant response to knock. I.e, when you hear knock (YES, I can hear it when it is BAD, but I was only running 5-7 PSI boost), the gauge responds within 0.5 sec.
· The OTC monitor shows KR after the Casper gauge goes off at a around a 1 sec delay.
· The first green light on my gage comes on around 1-3 KR and the second around 4-7. The orange light corresponds to 12-17 KR. (NO I did not blow a HG)
· I can hear knock when the orange light goes off, not when the green lights go off.
· Note that the car has a quiet exhaust system my audiograms are fine.

Point I am trying to make is this.
There can have around 7-12 KR that you may NEVER hear and will need a way to monitor/watch your knock. You have spend too much “blood sweat and tears” on that motor not to do this. If your mechanic tells you that all is well running 20PSI without a monitor knock, I would advice a different one.

A ASME Certified mechanic may be able to put the parts together but know nothing about these cars and even less in how to tune them. This is the reason why we study this board and some do the work ourselves. Just my $0.02

I totally agree that you can't hear knock until it's ~10 degrees. I've noticed this myself. The more power you're making, the less knock you can get away with. I detonated my stock motor pretty bad when I was new to this with no blown headgaskets. With my last modded motor, if I knocked, it was time to turn around and replace the gasket.

I have to say, my dad is one of the few stock hotairs that could run an honest 20psi with no KR on 92. Don't know why but it was a very strong 14.0 hotair with nearly no mods.

 

[BRAD_PADGETT]

I installed my Casper knock gauge this afternoon. When I get to 8-10lbs boost I have knock into the second yellow dot which is when I shut it down. I am planning on dialing down my waste gate actuator until I get no knock at WOT and 93 octane gas. Is this the right way to go? Any help is always appreciated. Thanks- Brad

 

[Jerryl]

Brad,
Right on!
Lower the boost until you have zero knock.
Having stated that, you should be able to run 9 - 10 PSI with no knock on 93. You may want to get some high octane gas and MAKE SURE it is not false knock.

Most likely will see transitional knock (i.e. during shifting), and you may want to ignore if it is no higher then 1 green light. At this point, you will need a scan tool to see how much KR that is and where your O2's are. Basically, you establish the max boost and fine tune from there. Here is where it gets to be fun!

 

[BRAD_PADGETT]

Jerryl- Should I put the original waste gate actuator back on? Would this be easier? Let me know your thoughts. Thanks- Brad

 

[Jerryl]

Brad,

It may not be a bad idea to set your baseline but probably not necessary.
Turn the rod in/out so it covers "halve the hole" to the connection to the puck.
This should give some good baseline tension on the rod.
What are your supporting mods?

 

[BRAD_PADGETT]

Jerryl-I just turned down the adj waste gate actuator down after several test runs. I now get 11lbs boost and no knock at WOT. I did get one green dot on a shift. I am going to leave it alone for now and see how it drives. My mods are-30lbs inj, Poston headers, Hooker hi-flow exhaust with test pipe, hot wired new gm fuel pump, Caspers Ultra chip burned to my set-up, 160 degree thermostat, frame brace kits, boost, tach, temp, and knock gauges. Thanks for all your help! The car runs slower than before but I am not going to blow it up. Brad