Boost level through gears?

[GrndNatnl]

I have a boost question, as I'm trying to play it safe.

I put in the Thrasher 92 a while back. (Some of you might remember reading my thread.) With the lines hooked to the wg-solenoid, it was just going way too high for pump gas and insufficient fuel system. Was hitting in the 20+ psi range. I took the solenoid out of the picture, and just controlled boost via the bleeder valve. I had it adjusted to about 16 psi and it ran strong, but it ran 16 psi all the way up to and through 3rd gear (never got the chance to hit 4th/OD).

Then I put the hose back onto the solenoid, then on the solenoid out port, I put a small hose to the bleeder, figuring it would still allow me to regulate the boost in first gear, and that it might allow it to drop down in higher gears. At the track, I got it adjusted right, and it would still spool up to 16 psi (or whatever I had it set at) in 1st gear, but it STILL stays at the same amount of boost all the way up through 3rd gear. Is this a dangerous thing to be doing? I know its a low timing chip for more boost to be safely reached on pump gas. But is it ok to run the same amount of boost all the way up? It feels fine, and pulls VERY strong. I just want to be sure.

 

[salvageV6]

What scantool or knock meter are you using?

If it isn't detonating it is safe to run the same boost in all gears.

If you don't know for sure it is always safe to assume it is not safe.

 

[GrndNatnl]

LoL, you have a good point there. Havent had a chance to hook a scantool up to it yet. As strong as it was running, I would assume there was no knock, but I know the only way to prove that is with the scantool. I may bring it to the track one more time within the next 3 Friday nights. (Which are the last of the season) I kinda just wanna put it away and not beat on it for the winter, and just wait for the mods and next track season to open up. But I'm egar to find out how well its running under the hood and hook up a scantool to it.

How accurate are the knock gauges? The LED light ones. I know a scantool is the thing to have, which I will. But I'm curious as to how accurate the actual gauges are, and how do they compare to the scantool? I've heard stories about the gauge showing something and the scantool not, or vise versa. Is the gauge a good investment?

 

[rastaz]

I run 20 psi with a Thrasher 92 in my TTA with no knock on 94 octane gas. This aside every car is different and you really must have a mechanical boost guage and a scan tool. The factory boost guage is crap...

 

[jojo]

Originally posted by GrndNatnl
LoL, you have a good point there. Havent had a chance to hook a scantool up to it yet. As strong as it was running, I would assume there was no knock, but I know the only way to prove that is with the scantool. I may bring it to the track one more time within the next 3 Friday nights. (Which are the last of the season) I kinda just wanna put it away and not beat on it for the winter, and just wait for the mods and next track season to open up. But I'm egar to find out how well its running under the hood and hook up a scantool to it.

How accurate are the knock gauges? The LED light ones. I know a scantool is the thing to have, which I will. But I'm curious as to how accurate the actual gauges are, and how do they compare to the scantool? I've heard stories about the gauge showing something and the scantool not, or vise versa. Is the gauge a good investment?

The knock gauge is worth its weight in gold. Mine is awesome. It will let you know you are detonating before the scanmaster and you can see it quicker as it lights up. (You dont want it to light up of course) but is very accurate in my case. I see the knock gauge light up first maybe while tuning, to the first couple or three green lights, and then check out the scanmaster and sure enough it reads about between 2 and 4 degrees of KR on the third green light going to the orange. Hope this helps. Its good to have both, due to the fact that you can see the knock gauge first at a glance before you have time to read the scanmaster at WOT.

jojo

 

[scottyb]

Btw, the move of your bleeder valve basically won't change a thing. The venting of boost by the bleeder(solenoid) is what controls the boost. More vent = more boost. Since the bleeder is the slowest vent of the two, it still has primary contol over boost.

Btw, you say that a thrasher 92 is running 20lbs??? Or is it a spike to 20, settle back to 17? Do you have an adjustable wastegate rod?

 

[GrndNatnl]

I know how the bleeder works. Thats what I meant when I was adjusting boost. I kept bringing it up a little by cracking the valve open a little more. Then turned it back down by closing it a little. With the valve fully closed, running off the wg-actuator diaphram only, the boost gauge (yes, aftermarket) would hit about 12-13 psi. (w/ the precalibrated level supposedly being 10)

I never had the time to see if it would settle back down to 17 psi. When I first put the chip in, let it learn a little, then blasted down the road at WOT, it shot up and buired my boost gauge (which only goes to 20 psi - its an autogauge boost & vac), just past 20 psi. I figured maybe the gauge was reading a few pounds higher then it actually was, being a cheaper type of gauge.

But I actually felt it falling on its face under WOT, and heard it pinging, so I let off the gas immediately. So I figure maybe it was correct. I didnt think it would boost that high off the chips control, so I now just use the valve to control it, and keep it down. No adjustable wastegate. Dont really need one now, heh. I still have the stock fuel pressure reg too, which kills me from running much boost. (I ordered the chip that works with the stock reg, for the time being.) I'm getting the adjustable very soon. I dont exactly remember what the boost was at, that day off the solenoid, but I think it hung around 19 psi once it hit 2nd.

 

[blackbuick87]

You cant run a stock regulator with a Thrasher, it needs 45psi line off. If you dont want to buy an adjustable one at least get a 237 regulator, they are set up at 43psi.

Have you tried buying a new solenoid?