Is this normal way for boost to work? (Video)

[Boozshey]

I noticed while on the dyno that my car was building boost like a Turbo. I've never seen this happen like this before has anyone else?

[nomedia="http://www.youtube.com/watch?v=PHX3_PXoEtw"]‪Boost on the Dyno... Still 2psi short.‬‏ - YouTube[/nomedia]

 

[Robertt305]

Looks fine... Just had a boost spike up top... Mine jumps up a pound and a half...

 

[Boozshey]

Oh yeah I didn't give enough information... I should be at 17lbs.

 

[Robertt305]

Then that's def the result of a bad cat.

Sorry didnt know your regular peak was 17 psi

 

[Robertt305]

If your usually at 17 then all of a sudden you start getting boost creep then a cat or both have failed and are increasing the pressure build up. Def take a look intonit cause that WILL cause engine failure.

 

[Boozshey]

Off road H... next idea? Haha... trust me I've been through another engine vdue to cat failure so I don't run them.

Also, I have yet to see 17lbs, I have a snake bite blower and both stegmier and the previous owner say I should see 17lbs.

 

[Robertt305]

Can't answer you on that one then... I'm not familiar with modified eatons.

Maybe posi will chime in later.

 

[stkjock]

Bruce has the car ever seen 17 since the swap?

 

[Boozshey]

That is correct. At first I noticed the stock boost gauge wasn't working so that's when I first hooked up the boost gauge to check. I saw 15 at wot but something didn't feel right. So I got a smoke test done and found an injector lost an oring during the blower swap. Replaced it and the car felt better. Then whent and got the cats deleted and went to get tuned. While being tuned I wanted to check the boost when I was able to focus on it and that's when I made that quick video. But the way its building boost concerns me. That spike is strange to me. With my iron block and just a 2.6 pulley I would see max boost at wot no matter what. Now its creeping up and then hitting at the top of the rpm range. It just has me concerned. I'm presently putting down like 548rwhp uncorrected and about 566 sae corrected. I feel that extra 2lbs will put me in the 580-590 range where its advertised to be.

Is the boost creeping like it is normal in high boost applications.

I am running an airraid filter, stock svt airbox and maf, jlt elbow, whipple super monoblade tb, then of course the ported snake bite blower with stock pulley.

Talking to steggi they said "I should see 17psi" and they want me to send them datalogs. However I even saw 1si with cats and normally you'll see less after the cats go away. So to me it seems that maybe my bypass might not be closing all the way?

I dunno...

 

[UnleashedBeast]

On hot days, I only see ~ 15.5-16 PSI

On cooler nights it will peak at 17, but I still have high flow cats on my car.

The boost on my car will almost immediately get to 14 psi, then increase slower up to 15.5 in the daytime, and 17 on cooler nights.

 

[stkjock]

Bruce

U can see on mine the boost moves twice. 12-16 then 17- 19

 

[Boozshey]

How much timing can we run?

 

[Illtaketwlight]

What size upper and lower pulleys do you have ?

 

[Boozshey]

Stock and stock... but its a snake bite blower. I think its compared to a 2" upper...