BLM @ 142 too high?

[The Darkside]

My BLM's were @ 142 for the past several months.....I recently found an exhaust leak at the driver side header to crossover connection.......Anyways, I installed some new poston headers & blm's are now around 128...

 

[87chrisss]

cool im going to take off this header tonight then and get it welded tomorrow and go pick up the gaskets i'll check back in once completed
thanks

 

[87chrisss]

also, now im thinking my converter is to tight... dammet if its not one thing its the other

 

[blackazz]

Yup its just about enuff to drive you crazy.I'm chasing a 142 blm too,pass side exhaust leak.

2nd place is 1st place loser!

 

[kidglok]

cool im going to take off this header tonight then and get it welded tomorrow and go pick up the gaskets i'll check back in once completed
thanks

have the flanges milled flat and run them without gaskets, one less thing to blow out and cause leaks.

 

[87chrisss]

2 people told me the same thing not to run gaskets but i ordered the good one's fel pro's

 

[87chrisss]

i cant just throw away my $$ so might as well use them if more people say theyve had good experience without gaskets i'll do it but only 2 people told me this... so i need some more assurance before

 

[kidglok]

are they graphite?

 

[87chrisss]

fel pro 1400

 

[TurboBuRick]

have the flanges milled flat and run them without gaskets, one less thing to blow out and cause leaks.

X2

Rule #1 Never use header gaskets on a turbo Buick. They will blow guaranteed. Just a mater of time. That's why the factory did not use them. Machine the flanges flat and use a little high temp rtv.

 

[TurboDave]

Yup!!! Both my GN's have gone in excess of 25 years without those stupid gaskets. Any time the headers had to come off, I just had them checked for flatness (adjusted as needed) and re installed. Matter of fact it's rediculous to use gaskets anywhere the factory didn't. What a waist. Header gaskets are almost guaranteed to blow out eventually, and the turbo to header gasket will for sure blow out under the extreme heat and pressure it's exposed to. I've even seen a solid copper turbo/header gasket get blown out.

No header gaskets
No turbo to header gasket
No downpipe gasket.

Just check your surfaces for flatnes, and then a realy thin smear of ultra copper.

 

[87chrisss]

ok so i changed out the header with another one i had that was already welded but i still have the 142 on idle

 

[87chrisss]

when i drive it'll dip into 128 130 but only while cruising...something is wrong...on my boost gauge on idle i have 15 14 vacuum,

 

[getdowngranny]

Just out of curiosity, have you checked your fuel pressure? I was having a high BLM issue on and it turned out to be that my baseline fuel pressure was high by 5 psi. I turned it down and it seemed to have tamed my BLM's. Sometimes you have to work around the problem to find it.

 

[The Darkside]

Are you 100% sure there no exhaust leaks at the header to crossover connection? That's where my leak was due to the mating surfaces becoming egg shaped & no longer round... Seems your vacuum is a little low too....Get about a 2 ft piece of hose(I use a piece of old garden hose) & put one end to your ear & use the other end to search around the engine compartment for any vacuum leaks...Listen for hissing around ALL vacuum fittings & even all along those old hard plastic lines(they get cracks in them sometimes)...check all around the throttle body & around the headers & like I mentioned before, at the header to crossover pipe connection.....

 

[87chrisss]

how vacuum do you guys have on idle?

 

[mgmshar]

how vacuum do you guys have on idle?

My car's been in the paint shop, so I'm going from memory here, but my vac/boost gage showed about 14 at idle with transmission in drive, and a little higher in park. I always wished it was a bit higher, but have never found any vacuum leaks or other problems. My engine has a stock cam.

Keep in mind that your cam and injector type can affect vacuum at idle. If you run big injectors, the chip maker will usually run a higher idle speed, which results in slightly lower vacuum at idle.

Mike
Sent from my HTC Droid Incredible using Turbo Buick

 

[87chrisss]

My car's been in the paint shop, so I'm going from memory here, but my vac/boost gage showed about 14 at idle with transmission in drive, and a little higher in park. I always wished it was a bit higher, but have never found any vacuum leaks or other problems. My engine has a stock cam.

Keep in mind that your cam and injector type can affect vacuum at idle. If you run big injectors, the chip maker will usually run a higher idle speed, which results in slightly lower vacuum at idle.

Mike
Sent from my HTC Droid Incredible using Turbo Buick

yea i was always under the impression that my vacuum being near 14/15 psi on idle was fine

 

[87chrisss]

dont know what it could be i remember setting my fpr when i put the adjustable on it, but then i havent touched again, maybe its time to review it but i cant find my fp tester anywhere≥.. im going to buy a new one

 

[87chrisss]

well just checked my FP it was low near 35psi line off, i raised it to where its supposed to be 42 line off, not sure where to look from here..bl still 142 on idle