bfellows

Just a little info needed from anyone running a Murf supercharger, or with more technical knowledge than me (shouldn't be too hard to find around here!)

My '88 S4 most probably does not have an in tank fuel pump fitted (https://rennlist.com/forums/928-forum/321778-does-my-88-have-an-in-tank-fuel-pump-fitted.html) as such I need to know if it would be beneficial to retro fit a pump as part of my install?

Feel free to be as technical as you feel and any advice appreciated!

(Please, no fighting just cause I mentioned the "S" word )

Ketchmi

Depends on how much boost you are wanting to run. If you are staying underneath 9psi, you shouldn't have to do anything other than make sure your filter is fresh.

Kevin Michael

9lbs. intercooled or 9lbs. non-intercooled?
Kevin

bfellows

Stage 1 non intercooled kit with whatever the standard pulley is? Filter is always changed as per service guide.

Ketchmi

You should be fine as the factory fuel pump seems to "run out of gas" at about 450ish rwhp. I just had one flatten out at 480 rwhp.

Hey Kevin, glad you are finally putting some boost to the ground. I wouldn't run 9psi without an intercooler, but if you did...either way. The engine is seeing 9psi one way or the other, it needs enough fuel to provide a proper mixture for the amount of air being force fed and 9 psi is 9 psi. Cooler is always better and you can overfuel a bit to compensate for no intercooler but I would not recommend it at all.

stuartph

Bert


Nice one

When will you have her up and running

bfellows

Order is being placed 2nd week in February! I've been steadily uprating brakes and generally making good (TB, waterpump, various hoses, filters, leaks, service etc) over the last 12 months or so. Just have to finalise shipping details with Carl and then I get to release the full Bwaaa potential!!

Fitting should be completed within a week or so of delivery as i'm in the lucky position that the father in law specialises in rebuilding race car engines and has a fully specced machine shop with full diagnostics and 2 full size lifts!

Any advice on the whole import experience? What to expect?

By the way, thanks to all above for the advice!

stuartph

Bert


Are you going for the polished supercharger or non, i've got the polished and it looks great. I'm gonna use 42LB injectors and a sharktuner to control the fueling and not use an FMU thats my choice.

The import was very smooth shipped and delivered in just under a week, i got my stage 2 from tim not carl, but i've got smaller stuff off carl and he is great guy also.

Oh and expect a nice big box

bfellows

Going for non polished - to be honest the rest of my engine bay would let the polished charger down, (much powder coating still to do) as I mentioned above, father in law has top end machine shop, so polishing at a later date is not a problem. My only concession to fashion at the moment will probably be blue silicon hoses (vain, but i like the look!)

I'm trying for a basic install at the beginning - hence standard injectors and no intercooler - get up and running, iron out any problems and then upgrade once i'm happy with each stage. I've gone hell for leather on projects before (cars, bikes, planes) and ended up throwing vast amounts of time money at problems and never being satisfied with the final result.

I'm guessing 285's on the rear will probably be an early purchase though..........

stuartph

I think that will be a good idea

I went with 295's on the back

SMTCapeCod

I know Devek used to offer a Bosch high-er performance fuel pump for very large (for 928) output powerplants. I've come across a unit billed as high performance on EBay UK as well....might have been a Sard unit.
Someone on EBay US has started to market Walbro pumps. These are an absolute mainstay of the tuner market for some marquees, and are reliable performers. Typically a little louder than stock. But you would need to do enough homework to know the output volume/pressure of the stock pump, and your target, in order to select the right Walbro. And then get the right fittings. I thought I remembered somebody that said the heck with it and bolted a big 'ol Aeromotive Sumo on their 928. Which also brings to mind another option- aeromotive and a few others make electronic controls that key off of the TPS or another indicator of throttle/load and jack up the voltage to the fuel pump at times of highest demand. Just make sure your regulator is up to the task!
I imagine that the internal pump might help up to a modest level of additional input, then I would think it might be an added restriction.

Jim R.

Bert,

With a stage 1, you should be fine if your pump is healthy. I've had a stage 2 on the stock 2 pump system (replaced both 2 years ago) with no issues. I don't think the small pump does all that much for total flow, but probably helps with hot starts, etc. I may upgrade someday, but it has not been necessary yet.........


Jim