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View Full Version : Spray meth before blower or smaller pulley ?



David Neibert
08-27-2008, 01:23 PM
I'm wondering how much extra boost is usually gained on an AR blower by adding a 2nd methanol injection nozzel prior to the blower inlet ?

I went from 20 psi to 23 psi by changing the 3.25 OD blower pulley to a 3.00 OD pulley, but that's a little higher boost than I feel comfortable with on 93 octane pump gas. I could get a 3.125 diameter pulley made that should produce about 21.5 psi, but if adding a 2nd nozzel will do the same, that might be a better way to go.

David

Kurt K
08-27-2008, 02:35 PM
Sounds like somebody is scared of the 2.0:p

bigpoppa822
08-27-2008, 03:19 PM
Come on Dave, live a little. 3" pulley AND another meth nozzle.

90blkbrd
08-27-2008, 03:20 PM
DD told me .5 to .75 psi.

David Neibert
08-27-2008, 04:15 PM
Sounds like somebody is scared of the 2.0:p

It's the Boy Scout motto........"Be Prepared"

David

Ira R.
08-27-2008, 05:02 PM
We pulled the second nozzle out of the system this spring because of pooling in the IC tubes. Last week the boost levels were between 20-22 at WOT so I didn't lose any boost by taking it out.

Does that sort of answer your question in reverse??

Ira

David Neibert
08-27-2008, 05:08 PM
We pulled the second nozzle out of the system this spring because of pooling in the IC tubes. Last week the boost levels were between 20-22 at WOT so I didn't lose any boost by taking it out.

Does that sort of answer your question in reverse??

Ira

Ira,

Yes it does answer my question, and that was one of my biggest concerns with spraying before the intercooler.

David

90blkbrd
08-27-2008, 06:58 PM
We pulled the second nozzle out of the system this spring because of pooling in the IC tubes. Last week the boost levels were between 20-22 at WOT so I didn't lose any boost by taking it out.

Does that sort of answer your question in reverse??

Ira

What jet were you using? I was considering do this over the winter.

Ira R.
08-27-2008, 07:32 PM
What jet were you using? I was considering do this over the winter.

I'll have to check. I have it written down here somewhere but I can't seem to find it. I will keep looking though.

Ira

Mike8675309
08-27-2008, 10:26 PM
I'm planning to remove the injector in front of the blower when I bolt the A/R on. With the more efficient blower I can't imagine significant improved sealing with it in front. On the old M90, it certainly gains close to 1psi.

David Neibert
08-28-2008, 09:13 AM
We pulled the second nozzle out of the system this spring because of pooling in the IC tubes. Last week the boost levels were between 20-22 at WOT so I didn't lose any boost by taking it out.

Does that sort of answer your question in reverse??

Ira

Ira,

Have you made some changes to your combo ? I thought you were only making around 18.5 pounds of boost when it pulled 450 rwhp at the Shootout last year.

David

David Neibert
08-28-2008, 11:44 AM
Hooked up my test gauge and drove the car to work today. I was hoping to see a reduction in boost after adding the longtube headers and much larger exhaust system, so I could overdrive the blower a little more to bring the boost back up to 20 psi and increase the power some.

I guess my old exhaust wasn't really as much of a restriction as I thought it was, because the test gauge showed the same 20 psi as soon as I nail the throttle :mad:

After consulting with Dave D. and reviewing all the stuff that may need to be done to keep the motor happy/safe at higher boost levels, I've decided to leave the boost alone, fine tune it and just use a small shot of nitrous if I still need more power to be competitive.

David

Ira R.
08-28-2008, 02:09 PM
Ira,

Have you made some changes to your combo ? I thought you were only making around 18.5 pounds of boost when it pulled 450 rwhp at the Shootout last year.

David

That is what it made on that one pull ay Precision. Think it may have had more to do with the weather this time then anything else. It did occassionally make more then 18-19lbs last year though not as much as 22lbs. At the track last week it was hot humid and awful and still a very consistant 20lbs. I myself am wondering why it was as high as 22lbs earlier last week. Altitude difference maybe, because it was considerable.

It is one of things I want to speak to Dave about anyway because I need to make sure it isn't messing anything up. Thinking of making an appt with Precision next month anyway just to check a few things.

Ira

David Neibert
08-29-2008, 11:43 AM
That is what it made on that one pull ay Precision. Think it may have had more to do with the weather this time then anything else. It did occassionally make more then 18-19lbs last year though not as much as 22lbs. At the track last week it was hot humid and awful and still a very consistant 20lbs. I myself am wondering why it was as high as 22lbs earlier last week. Altitude difference maybe, because it was considerable.

It is one of things I want to speak to Dave about anyway because I need to make sure it isn't messing anything up. Thinking of making an appt with Precision next month anyway just to check a few things.

Ira

Ira,

I'll finally be getting mine fine tuned this weekend while Dave is in STL doing some other stuff. Changing the headers and exhaust really messed my tune up. Fortunately Dave was able to loan me a scanner so I could provide him enough data for doing a long distance tune. It's running pretty good on that tune, but it still needs some tweaking to be 100%.

David

Ira R.
08-29-2008, 12:11 PM
Ira,

I'll finally be getting mine fine tuned this weekend while Dave is in STL doing some other stuff. Changing the headers and exhaust really messed my tune up. Fortunately Dave was able to loan me a scanner so I could provide him enough data for doing a long distance tune. It's running pretty good on that tune, but it still needs some tweaking to be 100%.

David

They always need some adjustment. The car is running great around town now and my tune isn't even 60 days old but I'm starting to notice some stuff that I think needs a tweak here and there. I am also getting some feedback off of a local dyno but they can't do the chip which is why I'm thinking of hitting Precision next month. And it's not like it's anything serious but that's just the next time I get to see the car, a dyno, Dave and my program all in the same place.

Ira