Changed out pulley- what's up with my boost gauge?

[fakesnake.com]

I put on a 2.80 pulley today. I am trying to baby it until I can get it to dyno and tuned with chip. I opened it once because boost gauge seemed to not be working. Boost gauge doesn't seem to work unless I am hitting 5k RPMS. Even then, it seems to drop right back down. It would go up before if I hit lower RPMS.

Is the smaller pulley taking longer to kick in now?

Am I missing something?

 

[matt lankford]

mine didnt do that. it is sad now that i can only hit 8lbs though, my car feels like a honda compaired to what it once was.

 

[SSCOBRA03]

My only guess would be a lot of belt slip.

 

[Dana]

I am sure you have thought of this already, but have you re-checked the belt tension? Sometimes the belts don't want to lay down in the grooves when you first install them.

Did you put on a smaller belt when you changed the pulley?
Is it small enough? Got enough tension?

Maybe loose vacuum lines to gauge? Check under dash and under hood.

Did you index the pulley to make sure it isn't spinning on the blower shaft?

Just a couple of places to start.

I would think that the smaller pulley would create more boost sooner on the RPM curve.

Dana

 

[fakesnake.com]

Did you index the pulley to make sure it isn't spinning on the blower shaft?

How do you do that?

I changed out belt and tension is tight.

 

[fakesnake.com]

I checked the way I ran my new belt (gatorback) and it looks like I ran it the proper way. Groves facing groved pulleys and smooth side of belt on idlers.

 

[Dana]

Just a little line of paint on the nut, washer and hub will work. If the line moves, something is loose.
Possible with aluminum pulleys, unlikely with steel.

Dana

 

[doubleblack]

are you running billet flow idlers to reduce slip...the guys on here w/ only a 2.8, smaller belt and no idlers say you will get slippage for sure.

 

[Dana]

Considering how fast these motors will wind up through the RPM range, try it in 3rd or 4th gear. See what happens. If you start out in the lower end of the RPM range and wind it up at full throttle even for a short burst, you should see what the boost is.

It sounds as though you did everything right.

Are you using an aftermarket gauge or the stock one?
That should not matter, just curious.

Dana

 

[fakesnake.com]

It pegged 10lbs in less then a second. I'm using stock gauge.

Indexed pulley and it isn't slipping.

Must have been be driving like a wimp first time out.

 

[Dana]

It pegged 10lbs in less then a second.

:thumbsup:

Dana

 

[kpinco]

Fakesnake: So how does the car feel with the new pulley and chip?

 

[fakesnake.com]

Kpinco,

I will let you know tomorrow after I get back from dyno tuning. Then I will really lay into it on the way home.

 

[kpinco]

Thanks! Please PM me with your results. I am following your lead! I talked to someone today about the 2.80 pulley and chip. Trying to decide whether I should do the Bassani mid-length headers first. Decisions, decisions!

 

[Hunter]

fakesnake - how many miles are on your new engine?

 

[fakesnake.com]

I have 2,500 miles on the new engine. I think she is broken in now.

 

[Hunter]

Yea, she's ready for the dyno!! Hey, how much out of pocket did the new engine cost you? If you don't mind telling.

 

[fakesnake.com]

I ran it through insurance so I only had to pay the deductible.

The new engine wouldn't run with my densecharger. Stalled 5+ times per day. I just put a Steeda CAI on today. No more stalls. My old engine worked fine with the densecharger.

 

[Hunter]

Wow, so you mean if I blew my engine I could claim it on insurance?

 

[fakesnake.com]

No, you have to run over something first.