Only 3 PSI??

So my 74 year old dad wanted a hot rod. Took an 86 MK VII drivetrain and stuffed it in his 84 LTD (the fox platform one). I thought it would be cool to get him a base 5-6 PSI blower kit since they are only about 2 grand. His AOD shifts @ around 4700 RPM. Pretty low, but thats what it is (dad likes to drive fast for a 74 old, but he is not going to constanttly do the AOD shuffle, he's just not interested :-)). If I run it out to 5500, I can barely squeak aout 5 PSI out of it. I tried a 3.12 pully instead of the stock 3.33 pulley in hopes of getting a little more boost @ alower RPM. Still only 3 PSI boost. Vortech tech is pretty useless so far. Could I be getting belt slippage @ this low an RPM/boost??

Also, I run a turbo kit of my stock engine 86 capri. The kit recommended to run 6PSI extra fuel pressure for each pound of boost (using stock injectors). I run 10 PSI boost witha total fuel pressure of 100 PSI and it runs perfect. Even when I wring it out in first and manage to get 5 PSI boost on my dads car, I only get around 57 lbs of fuel pressure with a 12:1 FMU. This sounds low to me??

Thanks in advance

The base 5-6 PSI blower is the A trim, which produces less CFM than an S trim does. Because of this, the thing is pretty much maxed out by 9 or 10 psi before it becomes a heat pump. I'm pretty sure the standard pulley on it is made for 5.0s to reach about 5 psi around 5,500 RPM. If the air induction into the blower is restrictive, it will lower its boost ability, but putting a tiny pulley on it to make a lot more than its standard boost is going to make it a less-efficient blower.

As far as the air/fuel stuff, I have no idea.

Thanks for the reply. This is the kit I got

http://www.superchargersonline.com/p...er=V4FA218-010

Supposedly, according to Vortech, the A-trim is no more. This new base blower (V-1, SC-trim, not sure what it's called really or if it's based off the S-trim??), is supposedly good to well over 10PSI. I don't want to make more than the 5-6 PSI boost, I just want to make it at a lower RPM than 5500. If that is what you mean, that I would be over-revving the blower to do that, then I won't attempt it. I would assume though, if the head unit is really capable of 10 PSI or more @ 5-6000 RPM, then it should be capable of 5 PSI @ 4500-4700 RPM. From what I'm reading, unless I get a valve body and/or a shift kit, I can't easily raise the AOD shift point, so I want to lower the point max boost comes in to match the tranny shift point. So much easier to change boost with the turbo kit on my car, thats for sure :-).

Thanks again

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Originally Posted by Shane's93LX

The base 5-6 PSI blower is the A trim, which produces less CFM than an S trim does. Because of this, the thing is pretty much maxed out by 9 or 10 psi before it becomes a heat pump. I'm pretty sure the standard pulley on it is made for 5.0s to reach about 5 psi around 5,500 RPM. If the air induction into the blower is restrictive, it will lower its boost ability, but putting a tiny pulley on it to make a lot more than its standard boost is going to make it a less-efficient blower.

As far as the air/fuel stuff, I have no idea.

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Are you fuel injected? Double check your hoses etc. and look for leaks. Is the blow off valve stuck open partially? It should start making boost around 3,000 RPM and Max out around your redline of 5,500.

joe