How much boost are you all runnin' on 93 octane?

[BlackBeauty]

Hey guys, I see in the e-mail list, people are talking about running 25psi on 93 octane! I have never heard of people running more than 15psi on 93, and only running 18 or 19psi with xylene mixed in. Personally I am afraid to run more than 14psi on 93 octane (if I cap the port on the wastegate solenoid, I get 14psi, otherwise the lowest I can go with the rod is 18psi). I was get some opinions on what you are all running, so I can see how much boost I can run without the alky.

My set-up:
Walbro 307 & hot-wire
Adj. fpr
bluetops
9" K&N
SMC alky kit
Hooker cat-back
the proper AC Delco spark plugs
Thrasher 92
Adj. wastegate rod
I think that's about it, of course I have a boost gauge, knock gauge, and ScanMaster.

I also have a TE-44 that I hope to install tonight or tomorrow. But I've been running the stock turbo. I assume a powerplate would help, as well as a more efficient intercooler. Thanks!

 

[PsychoBuickBoy]

93 Octane!!!!!! Wow your lucky, highest they sell here now is 91 at the pump. There are a few places that sell 101 for like 4 bucks a gallon. Anyways, I was never able to run anything over 15 psi with straight 91 octane. Even the alky is hard to tune because you have to set the turn on point so low.

 

[opzWE4]

Well, I see people running high boost on 93 octane, but it ain't happening here. The most I can run on 93 is about 15psi, and that seems to be on the edge once in a while. I run xylene mix most of the time and leave it at about 17-18psi. I'm not sure how people run 20#'s of boost on 93, I'd blow my motor apart if I tried too

 

[scottyb]

I ran 17 lbs on 93 with my Red Armstrong chip with about 3+ degrees knock in 3rd gear, and I wasn't too comfortable with that. I put in a Thrasher 92 last weekend and have it at about 18lbs with 0 knock.

 

[Crazi]

I remember a post a while back about some guy running 20+ psi with 93 and I cried foul. Then I went out and tuned my car and low and behold... 20 psi on pump gas! I did some more tuning and got up to 22 psi with the stock turbo and pump gas! I am running a front mount and I ported my own heads and polished (as best I could) the combustion chambers so that helps.

Well now, I upgrade everything, while it is apart I go back through the heads and clean up somemore, and put it all back together. I break in the engine and tune it to guess what... 20-21 psi with my current combo. This is on Chevron 93!!! I have the alky all hooked up and ready to go but what for, I am having too much fun!

The moral to this story is do your home work. I have been reading about head porting since 96. I practiced on an old junk head for about 6 months. I used grinders and different wheels/bits to make stuff just for practice. And I read the Standard Abrasives tutorial about 15 times.

Fast forward to 2001 and I am porting the heads on my buick, polishing the chambers, and using my finger as a guide. No flowbench, no pro to look over my shoulder. Just a good understanding of airflow and venturi's and such. 20+psi on 93 can be done.

 

[BLACK6PACK]

I was never able to run more than 17 psi on 93. A lot has to do with the timing in the chip. If it is fairly aggresive, then you won't be able to run a lot of boost. A front mount and ported head help also. Crazi sounds like an exception rather than the norm.

To run 24 psi on 93 octane i would bet they are also running alky injection.

 

[Crazi]

PS

The RA chip I have in now has 24 deg of timing! I never thought I would get to 20 either but the cold air does help. The chip was burned with alcohol in mind.

 

[BLACK6PACK]

Crazi, thats crazy!

Sounds like we have a somewhat similar setup. How does your car spool with that converter and the 54? What kind of times have you ran?

 

[turbo todd]

20 psi

I can run 20# on 93 fuel in 1st, and 2nd. 18 in third. Sometimes I get a little knock on top end. ( no more than 2.5) This is all possible with the thrasher and power plate!!! Never thought I could do this. Was kinda scared to try. But you only live once.

 

[Chris Taylor]

I have tuned Kevin Wood's 30,000 mile T Type to run around 20-21 psi of boost on 93 octane not KR. I will have him chime in and tell about it. This car is awesome. It ran 7.20's in the 1/8 before the V2, Power Plate, air bags and 10" stall. This was with JL race chip and 25 psi of boost. I feel sure that this car will run 7.0's or high 6.90's in the 1/8 with race set up.

His set up:

Unopned motor
JL street chip
RJC Power Plate (Before PP ran 18 psi of boost)
Walbro 340 Hot wired
Volt Blaster (They do work)
50# injectors
PT51
V2 front mount
THDP
10" NL JW 3,200 stall
Scan Master
Ram Air
ANS boost controler
Air bags
2 3/4j dual exhaust

 

[gnXfan]

17-18lbs on 94, testa chip

 

[JDSfastGN]

On my combo below on the 87 GN I was running 19#s and still tuning with no knock at all. That is on a PTE 20* timing chip. That didn't include the ported and polished heads or the 204/214 cam and stuff, thats the new stuff that is going on. Unfortunatly the day after, I wiped my cam. I had only had the turbo on for a day, so I believe there was a lot more to tune out of it. 20#s is very possible on 93. On my stockish combo and a thrasher I could run 22#s in 1st gear , 20#s in 2nd and 19 in third or so. Every GN guy I ran into wouldn't believe me until I showed them. One guy had no idea how to tune and i ran his Turbo T with a te44 50#s injectors and a lot of other goodies and I pulled him pretty good with my stock turbo and injectors(I had the 23 row intercooler). After he learned to tune it and was able to run 18, he ripped me a new one.

 

[dpok69]

With thrasher 92, and 93 octane 17-18 psi with minimal knock. 02's at 8-8.50 and engine not fully tuned. I have a very good flowing exhaust and the powerplate helped alot.

 

[Crazi]

Hey Black,

I haven't been to the track yet. I can't find an oil leak and don't want to fail tech because of it. Anyway, I used to be scared to go above 15 psi with this combo until I ran my buddy in an ls1.

I went up to 18 and had no knock but couldn't get by him. We were dead even. So I kept tinkering and got to 20-21 and had shift knock but that was it! We didn't race again but judging by the ease of getting sideways now, I can take him. I think I still have more tuning left cause I get 750 o2 with no knock. Maybe some more fuel pressure and 1-2 more pounds and then.... then alcohol!!! Man, now I know why I love this car

 

[forzfed]

Up here in Canada lot of the guys in my car club run an ethanol blend 94 octane. With a thrasher 92 I was able to run 24psi with stock turbo. One guy in the club runs the thrasher 100 with 22 psi on stock turbo and gets 3 degrees of knock in high gear. With my TE-44, I run 22psi with 18' on the ME chip. The most I've gotten was 2.6' of knock in overdrive. This is through the stock exhaust, so I'm sure once that is upgraded I might be able to go another pound or two.

 

[kenny]

21#'s on 94 octane, Lubrant chip.

Most KR I see is 1.2 on the 1-2 shift.

V2 rules.

(this is without alcohol injection btw, I don't even have an alky kit on the car)

 

[BLACK6PACK]

Crazi,
I'm running the max effort chip with 24* timing on the race settings. I'm able to run around 25 lbs of boost with no knock. I hear you on being scared with this combo. I won't drive the car without drag radials on it. If I lay into it from a 10-15 mph roll, it will start spinning the tires around 20 mph, hit second and get traction after a second or so, then around 50 it starts spinning the tires again - WITH THE DRAG RADIALS!. Before the drag radials it was like driving on ice.

I've only had it to the track 2 times with this setup, and haven't had a lot of time to tune, so there is a lot more in it.

 

[BADINBLACK6]

17lbs w/thrasher 92 on 93 octane but boost would drop to 14 in 3rd with no knock. 23lbs with alky and a JC 93 no knock and as soon as the rain finally stops here I'm going for 25 lbs

 

[tracer]

forzfed, who sells 94 in the peg? Out west here the best I can find is Mohawk 92.

 

[ecmo92]

Using PTE's 100 chip I was running 18-19 pounds of boost with no KR. Thing ran great. This is on 93 octane. Would the ported heads have helped that much? Also a stock intercooler before the neck.