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22lambo
05-25-2009, 12:44 PM
So I will be dynoing my Camaro for the first time. It is supercharged at 5 psi. There isn't much mods to the engine that I know of but in the club I am in there is a guy with a ls1 and he dynoed it at 391 at the rear but he has done more work since the dyno but in 4th he was only inching away. So the club I am in they are having a dyno day and the dynos will be $30 for 3 runs so I am jumping on that deal. Any advice before and when I am dynoing it?
22lambo
05-25-2009, 12:47 PM
Also my powerband stops at around 5000-5200 so should I tell them to stop it there?
BLOWNDFIZ
05-25-2009, 12:53 PM
My advice is to get yourself 5 gallons of unleaded race fuel (VP MS109 or equivilent) and put in the tank. Just to play it safe.
22lambo
05-25-2009, 01:05 PM
The guy who had the ls1 told me that he hopes that whoever put the SC put lowered the compression because when forced induction you don't want high compression. So doesn't race fuel raise the compression?
Z28pr0jekt
05-25-2009, 01:17 PM
No race gas doesn't raise the compression, it give extra octane which provides a cushion for the boost so you dont incur detonation.

Even if it is a stock bottom end, 5psi is not much and unless the motor was beat to hell it should last a good bit on only 5psi
22lambo
05-25-2009, 01:27 PM
Oh that right. Ok then, I will do that. Should I add it to the gas or run the tank clean and run it only on the race gas and also does it add more power?
Z28pr0jekt
05-25-2009, 01:36 PM
Race gas itself does not add any power, it allows for additional boost or timing before detonation will occur. If you can, try to find unleaded race gas, it is better for your O2s but one time of 5 gallons of leaded gas will not destroy the O2s.

You do not need to run the tank clean.. if you run it down to about 3-5 gallons left and then add the race gas you will be fine, make sure you run the car for a few min with the race gas before the pull so it has time to mix.
boosted95z
05-25-2009, 01:40 PM
Well I hope you had the car tuned? Also, 5200 rpms is short shifting these cars. I took my stock engine to 6k and it spun like a top. That is, until the ringlands went. Stock engine + 8 psi = bye bye ringlands. As for advice? Pay to get the A:F ratio taken so you can see how rich or lean your car is running.
mpe331lx
05-25-2009, 01:45 PM
Oh that right. Ok then, I will do that. Should I add it to the gas or run the tank clean and run it only on the race gas and also does it add more power?

Just add it to a 1/2 tank. If you run it straight and your tune is already somewhat safe, you'll probably lose a little power.

Race gas is not a magic power adder. It allows you to run more compression, more timing, and more boost than you would be able to do on 93 pump gas.

Adding some to a setup that has an unknown tune is just a good idea to be safe.
22lambo
05-25-2009, 01:50 PM
Ok, that is what I want to hear. Also about the powerband. Right not it got higher to about 5100 but a month ago it would stop pulling at 4700. No can tell me why. Also when we changed the plugs they were a little on the rich side.
boosted95z
05-25-2009, 01:51 PM
Ok, that is what I want to hear. Also about the powerband. Right not it got higher to about 5100 but a month ago it would stop pulling at 4700. No can tell me why. Also when we changed the plugs they were a little on the rich side.

Did you clock the MAF?
Z28pr0jekt
05-25-2009, 01:57 PM
Could have been pulling timing if you're getting knock, you would have to get a datalog to be sure
22lambo
05-25-2009, 02:12 PM
Did you clock the MAF?

What do you mean by if I clocked it?
22lambo
05-25-2009, 02:13 PM
Could have been pulling timing if you're getting knock, you would have to get a datalog to be sure

I have a boost retard control and I have been messing with it and no matter what I dont have and knock or pinging.
boosted95z
05-25-2009, 02:52 PM
What do you mean by if I clocked it?
Rotated it to catch the incoming air. Is the car a draw through or blow through setup?
22lambo
05-25-2009, 03:04 PM
Rotated it to catch the incoming air. Is the car a draw through or blow through setup?

I am pretty sure it is a blow through. I have a Vortech V1 on it.
boosted95z
05-26-2009, 12:59 PM
I am pretty sure it is a blow through. I have a Vortech V1 on it.

Okay, so it's after the blower, and before the TB? If so, try rotating the MAF 90 degrees counterclockwise and see what rpm it goes to. The physics of the airflow coming from the blower has the air going around the sides of the MAF and not catching the air on the wires which gather data. If you rotate it, it can catch that air and get a proper reading. The MAF needs at least 6" of straight airflow for it to run in a normal position. The boost piping (outlet of blower to TB) isn't straight and thus your MAF needs clocked.
22lambo
05-26-2009, 05:38 PM
Okay, so it's after the blower, and before the TB? If so, try rotating the MAF 90 degrees counterclockwise and see what rpm it goes to. The physics of the airflow coming from the blower has the air going around the sides of the MAF and not catching the air on the wires which gather data. If you rotate it, it can catch that air and get a proper reading. The MAF needs at least 6" of straight airflow for it to run in a normal position. The boost piping (outlet of blower to TB) isn't straight and thus your MAF needs clocked.

I will try that but I just figured out something. I have this paxton box on my camaro and there is a vacuum tube that goes to it. If the tube is hooked to the box, the powerband stops at 4700 rpm. When I don't have it hooked up, then it goes to like 5200. Why the heck is it doing that?????
mpe331lx
05-26-2009, 07:14 PM
I will try that but I just figured out something. I have this paxton box on my camaro and there is a vacuum tube that goes to it. If the tube is hooked to the box, the powerband stops at 4700 rpm. When I don't have it hooked up, then it goes to like 5200. Why the heck is it doing that?????

That sounds like a boost referenced timing retard. When you pull the line off, it (the timing retard box) is not reading any boost and is not retarding your timing.

By the looks of your posts, tou bought the car with the blower on it correct? And it is very possible that it is un tuned, correct?

I would start doing some research on what parts are on your car currently and what it SHOULD have to be optimal.


If it has the timing retard box, it probably has an FMU and stock or injectors that are too small for ANY forced induction application.

I strongly suggest a few things:
ditching the FMU (if it has one)
ditching the timing retard box
36-42lb inj (60s if you plan on upgrading to a built motor with good heads and cam)
Racetronix 255lph fuel pump
Getting dyno tuned by an experienced lt1 tuner (you must do this to remuve the FMU, retard box, and add bigger injectors)
****correct heat range plug gapped at .32**** This could be your issue!

If your plug gap is too big. it will blow out the spark on the top end.
22lambo
05-26-2009, 07:31 PM
Correct, I bought it with it on it and I am not sure if it has been tuned. It does have that paxton box (fmu box I am guessin), and it has a boost retard nob. Also, how would I know if it has stock injectors? Also I live in CA so where could I find a good lt1 tuner? Thanks for all that info. I will save up some money and do that. One more thing. I have a 5psi pulley and I was wondering if I could get a smaller pulley on my engine assuming it is stock. Thanks.