US engine charactoristics

[XLR8928]

I am contemplating future mods on my 4.7L us motor. I was hoping one of our 928 scholars would be in the know.

1) What is the air flow registers (flapper) CFM rating, and the throttle body diameter?
2) Can I run a euro cam with the 4.5/4.7 us computer, and would I need to make any mods?
3) What are my options in the aftermarket?

As always, thanks
-Kerry

[stepson]

1)Someone will know the real answer to your first question, but I can tell you that it is too small. Barndoor flappy is restrictive.

2) Yes, you can. It will not gain it's efficiency to potential without changing the intake, throttle body, fuel mapping and exhaust.

3) Euro runners and throttle body, and Y pipe would be your best bang for the buck.

[XLR8928]

I realize that I'm running restrictions thru the intake, and small valve/port heads, ergo my power goals are modest. My main goal with the cam is to extend my torque curve into higher RPM. My current set up is: K&N air filter, tubular full length headers, dual 2.25" into 3" Y pipe, 3" exh thru a 3" magnaflow muffler. I am also running at 28 deg advance. Ultimately, I would be OK with 260HP. Got any euro stuff you want to part with (reasonable)?

[kelanel]

Euro heads and cams from an 84-86 + the spider upgrade (bigger ID but the same OD) with headers should get you around 280-290 from what ive read from one of greg browns older articles. The euro s intake throttle body is much bigger than the US but the AFM would not fit since it is designed around a maf.

If you wanted to truly invest in something like that, going toward a standalone ecu would be the next logical step if you adopt the euro TB since the maf can be switched out for hose and you would use a map sensor instead. new ECU with better ignition unit would allow for a much hotter spark (wider gap) and fuel/timing control to where its actually tune-able on a dyno.

[stepson]

Originally Posted by XLR8928

I realize that I'm running restrictions thru the intake, and small valve/port heads, ergo my power goals are modest. My main goal with the cam is to extend my torque curve into higher RPM. My current set up is: K&N air filter, tubular full length headers, dual 2.25" into 3" Y pipe, 3" exh thru a 3" magnaflow muffler. I am also running at 28 deg advance. Ultimately, I would be OK with 260HP. Got any euro stuff you want to part with (reasonable)?

HA HA HA. No I don't but stuff does come up on Fleabay sometimes

[harborman]

Unless you are willing to spend many $$$$$$, I would just do the muffler & pipes. The stock 928 has plenty of power as is. Why open up a whole new set of problems. Drive it and enjoy it.

[XLR8928]

Originally Posted by harborman

Unless you are willing to spend many $$$$$$, I would just do the muffler & pipes. The stock 928 has plenty of power as is. Why open up a whole new set of problems. Drive it and enjoy it.

I've already done the exhaust system, so At this point if I can find a stouter cam for the 4.7 I'll be happy. Danglerb said he has a '78-79 cam which has the same lift, but a little more duration (worth a few ponies) I'm still exploring the aftermarket as well. Since this is a replacement motor that I'm freshening up anyway, It's no big deal to change out cams on the engine stand
-K

[kelanel]

while you are hunting for cams, this might catch your eye. someone just put up a set euro S valves if you are interested, you would need to check if the same springs fit, and port your heads to match the new valves. that will definitely open it up a bit. FS: Euro S Valves - Rennlist Discussion Forums