Not 2fast? 1997 Riviera SC, whats the problem?

Hello all fine people!

Here I have some headache... My wife drive supercharged 1997 Riviera and my daily commuter is 1994 Park Avenue Ultra, which as you all know have older Series I supercharged motor in it. You know power is 240hp versus 225.

Soo, my devastating problem is, that 1994 Park Avenue is much faster than '97 Riv!!! Why o why? Can it be some MAF related problem?

Both engines are bone stock, Series I seems to have little smaller SC pulley, but it looks stock. I suspect MAF in Riv, because I know it can be "clogged" or something like that..

Ofcourse both are serviced with new filters and plugs and such, but Riviera doesn't even burn these 245 meats from the stop (ofcourse traction controll off), but PA happily ignite rubber and my smile!

What type of gas does your wife put in the Riviera?

weight can change a lot

As of weight, these two weight pretty close, so not an object. Gas is high octane european standard E98 comparable to premium gas in U.S. So its not an issue either.

gearing maybe

A "C body" Park avenue Ultra is about 350 pounds lighter than a Riv. A C body Park Avenue weights about as much as a Regal GS. That is why the 1996 Park Avenue Ultra (first and last year of C-body/Series 2 motor) is the fastest stock park avenue ultra year.

arttu80 wrote:

I suspect MAF in Riv, because I know it can be "clogged" or something like that..

Ofcourse both are serviced with new filters and plugs and such, but Riviera doesn't even burn these 245 meats from the stop (ofcourse traction controll off), but PA happily ignite rubber and my smile!

If it is a dirty MAF sensor then a $5 dollar can of MAF cleaner can fix that in 10 mins.

The Riviera may have an issue that Oldman's Riv had, where the boost Bypass was faulty and was constantly dumping boost not allowing the supercharger to build up more than 3 pounds. He ran with this problem for about 1 year and a half just thinking that he had for some reason a weak motor.

I would advise that you hook up a boost gauge and see how much boost your RIV is getting. If I recall correctly, it should be around 8 pounds of boost.

Buickman104 wrote:

arttu80 wrote:

I suspect MAF in Riv, because I know it can be "clogged" or something like that..

Ofcourse both are serviced with new filters and plugs and such, but Riviera doesn't even burn these 245 meats from the stop (ofcourse traction controll off), but PA happily ignite rubber and my smile!

I would advise that you hook up a boost gauge and see how much boost your RIV is getting. If I recall correctly, it should be around 8 pounds of boost.

agreed, you would probably not break traction on dry pavement without getting full or near full boost.

Clogged fuel filter perhaps?
Air filter, also if you recharged it, the red oil can come off and coat the maf

A suggestion to consider the normal tune up items.

Plugs
Wires
Cleaning maf and iac sensors along with a throttle body cleaning.
Check exhaust for clogged cat or too much back pressure

Ah, thanks a lot "Buickman104" for advice on bypass valve and stuff, I absolutely try to hook boost gauge as soon as I can!

As for normal tuneup items, they're fine. New plugs, ALL filters and such, so it's very probable that supercharger isnt up and going! Good advice man!

But I just couldn't agree about weight figures you provided, as base curb weight for Riv is 3690lbs and same year PA Ultra (1996) is 3642lbs. And this is from my 1996 Buick Brochure!

Oh, btw mr. "urbsnspices", Isn't "Fear and Loathing in Las Vegas" best movie of all times!

arttu80 wrote:

Oh, btw mr. "urbsnspices", Isn't "Fear and Loathing in Las Vegas" best movie of all times!

I'll step in and answer that.
..Yes.

arttu80, although it may be other mechanical things, keep in mind that the series 1 supercharged engine coughs up its horsepower at a much lower RPM than its younger brother the series 2. Stock for stock, a series one will almost always beat a series two off the line... however that advantage gets quickly lost once the series 2 hits its horsepower RPM. Once you have a modified series 2, however, the series two will often surpass that initial off-the-line trait of a series one.

Edit:FYI .. the smaller pully you noticed on the series one is because of its less efficent blower. The m62 on the PA puts out about 1 litre of air per revolution, vs the 1.5L of the M90. Also i believe pre 95 m62 blowers were again less efficent than that of the 95, so a 2.5" pully was included vs the 2.8 of a 95 M62.

arttu80 wrote:

Ah, thanks a lot "Buickman104" for advice on bypass valve and stuff, I absolutely try to hook boost gauge as soon as I can!

!

i believe you can disconnect a vacuum line off the FPR or BBV and blip the throttle cable - the vacuum/sucking should change to blowing/boost.

Thanks Karma for good facts!

Karma wrote:

Edit:FYI .. the smaller pully you noticed on the series one is because of its less efficent blower. The m62 on the PA puts out about 1 litre of air per revolution, vs the 1.5L of the M90. Also i believe pre 95 m62 blowers were again less efficent than that of the 95, so a 2.5" pully was included vs the 2.8 of a 95 M62.

your right the 94-95 M62 had Teflon added to the rotors, it made the clearances even closer thats why its more efficient them the 92-93