Rogue_Ant

What kit are you talking about?

Mongo

Josh, I don't remember you guys making a 928 kit. If you are eventually, I am sure some of the 16v guys will be curious about it on here.

Rogue_Ant

We don't have a 928 kit, which is why I am confused as to what Mark tried to use..?

I haven't followed the 928 stuff much, as I thought all the 928 guys just went with the Shark-Tuner offering?

Mongo

Sharktuners apply only to the 32v cars with LH 2.2 and 2.3 versions.

There is no current tuning product available for L-Jetronic cars, yet...

James Bailey

Not to worry Mark has a similar effect on most......

Mongo

I LOL'd and choked on my lunch.

mark kibort

we are talking about an AFM to mass air meter conversion kit. it uses the Mustang MAF and some tuning contoler and interface to the existing ljet. problem is the voltages were way off and couldnt make it work
so , after battling it for a while, i sent it back

It was the 944 guys that steered me to a company in arizona. dont rememeber who.

Jim.... you just cant help yourself...... funny!

danglerb

There are voltage remapping devices, one of the 928 Turbo guys uses them. Simple device, no idea why it costs like $500 but takes an input voltage and remaps it to any output voltage you want.

Unless you do a LOT of work, more than just cams and exhaust I don't see the barndoor meter as major weak link on an early 928.

Most HP related exhaust mods LOWER bottom end torque because of reduced exhaust velocity at lower RPMs, at best most are neutral or shifting torque band higher.

Landseer

Here's the cliff notes on simple addition of 85/6/6.5 headers:
Remove exhaust manifolds and pipes.
Mount the later header units ( you need some crush rings )
Bolt the DS header to the DS downpipe.
Apply torch to where DS pipe enters cat to soften it.
Bend that pipe so the cat is recentered in the tunnel.
It will be clear, then, where to cut off the PS downpipe in order to fit a short spacer pipe, effectively moving the PS flange to where it meets the PS 85 header.

MIG or TIG the spacer into the PS downpipe.

Pretty straightforward job. Use a variation of it for whatever downpipe arrangement you are trying to adapt to. I use the 928 downpipe/cats because up til now they've been throwaways for the X-pipe guys. In fact, I just move the 32 valve cats to the earlier cars --- my version of a high flow cat.

danglerb

I've got a couple dual cats, a stock one, and a fabbed single cat, the issue with the adapter is that both side of the factory flange have the pipes at an angle and the adjustment is 2.25" straight back, and I don't like \-\ in the middle.

I wish I had better luck on the factory dual cats, bought two so far, one has a cat totally missing, the other has a cracked cat tinkling on one side ready to fail.

I also have two new Calif Catalog Magnaflow cats I am thinking of having made into copies of the factory dual cat with the offset for 85/86 manifolds built in.

Plus of course before I put everything in I want a bunch of it Jet hot coated.

mark kibort

what we have found, universally, is that the exhaust mods change the HP torque curve upward evenly by about 7ft-lbs from beginning to end. the most of the time you loose HP or torque, is when you change the cams

the barn door AFM is not the restriction, its the size of the opening. if you could find a larger one and adapt it, it would sove the problem.. that really being,its a restrictor. think of it like having a restrictor plate , like in racing. its only 3.xx square " . I forgot the exact dim.... but, its like having a 50% restrictor plate compared to the euro or other CIS versions.
its one of the reasons why a 79 4.5 can make near the same rear wheel hp as the 4.7 US with the Ljet. (besides the cams being a little better.

I have NEVER seen an exahaust mod lower bottom end torque and HP on a 928.

if you want to post the HP curves you have, lets see them? I have quite a few that show a shift up , universally of the hp and torque for both an exhaust mod (less restrictive) and headers.

Landseer

Exhaust mods can make the 16 valve cars sound amazing. Even with the 32valve factory cats I'm adding, combining to a big single, some sort of resonator and a big 3 inch single out the back is worth giving up hp, torque and cash. Just for the sound.

123quattro

I would agree. I've got a lot of compliments on how my car sounds. I'd describe it more as a rip than a rumble. It wasn't what I was expecting when I built the exhaust, but was pleased none the less.

Mongo

This is exactly what I did to my S4 to model the 16v soind as close as I could.. Single 3" after factory cats. I really, and I mean REALLY like how a single pipe exhaust sounds over duals now.

Not sure what the gains are but there sure as hell is no loss in power and grunt.