PDA

View Full Version : Help with base tune up for a Race Aero turbo motor



RaceAeroMini
07-17-2006, 08:03 AM
I have bee lurking for years and I finally have my boat out of the corner of the garage and running in the driveway.
I have got it running well but I had a couple of questions.
1. I have the initial timing at 12 degree BTDC and total at 34 degrees. The engine idle speed goes up until about 20 degrees BTDC. It also is smoother with more advance.
What do you guys recommend for initial advance? I will want about 30 to 32 degrees total and will adjust the Mallory advance to get that total correct. It has been recommended to run the distribuer locked out at 30 degrees. I may still do that.
2. Where do the idle mixture screws usually end up? I started with all four 3/4 turn backed out. The carb is a Holley 9380 annular. The exhaust smelled rich and I closed down to 1/2 on primary and 1/4 on secondary. The engine doesn't seem to change idle speed except when they are closed all the way.
Thanks for the help.
Jim

RaceAeroMini
07-18-2006, 04:19 AM
I figured someone would have an opinion. Thanks anyway. I'll run it with 12 degrees initial and 32 total and see what happens.
Jim

schiada96
07-18-2006, 05:33 AM
I'd run it locked out at 30 and check for a vacumme leak

ColeTR2
07-18-2006, 05:58 AM
locked out 30 ~ 32. are your running pump gas?

RaceAeroMini
07-18-2006, 06:44 AM
For tooling around the lake with the wife and kids I am running pump gas. I don't have a boost gage as this was a minimalist ski race boat.
For running hard I run 100 LL.
Does anyone know how much boost I should be making. Rajay 301E10 turbos with some kind of cam. I am guessing an Engle TCS7. I can turn 6200 rpm with the gears in the box now, whatever they are.

RUSHIN ROULETTE
07-18-2006, 07:27 AM
I see about 14 lbs. of boost at 6000 rpm with 50% gears. I run 110 octane always.

MKEELINE
07-18-2006, 07:55 AM
You should really look at putting in a boost gauge, along with a fuel pressure, oil pressure/temp and water temp gauge(if you don't already). These will give you some basic info that can be very useful :) .Is your setup a single carb?

RaceAeroMini
07-18-2006, 08:36 AM
This is an 18' Hallett Mini with the radiused keel. It's an old ski racer. The previous owner was Richard Babcock. I've had it about eight years but I haven't run it since my number two was born - five years.
The engine is a 454 with 990 heads. The turbo system is a single carb race aero. Currently I have a Motorola tach, oil pressure and water temp. The previous owner said they ran 100LL fuel and it was fine for whatever boost it was making.
I am assuming the ski racing folks used this engine on a regular basis and it worked fine with this sort of standard setup. It's run fine without being taken apart for 20 years or so. I was told it was a Dunsmore boat. It is rigged like a flat bottom. Engine 29 inches forward of the transom with a 7 degree shaft angle.
What do you guys run for oil? Right now I have twelve quarts of Castrol racing oil, straight 30 wt.

RUSHIN ROULETTE
07-18-2006, 09:01 AM
I run 20/50 torco mpz racing.. 14 qts.

MKEELINE
07-18-2006, 09:39 AM
20/50 Valvoline Racing 12 quarts.

RaceAeroMini
07-18-2006, 10:39 AM
I ran it last night and didn't find any vacuum leaks. With the turbo system, there are lots of things to check. It will idle at about 800 rpm. I was happy with that. I have the mixture screws at 1/2 P and 1/4 S.
Is this normal or am I missing something?
Thanks for the help guys.
Jim

whale
07-18-2006, 02:39 PM
I have the same set up on a 21 foot Rayson Craft Day Cruiser. My set up has 2 - 750 Holleys...it also has been de tuned to 9 psi....it also has a MSD Multi step Retard set up on Hobbs Switches. I run 30 degrees total under boost. Engine is 468 BBC with Aul., open chamber heads and a mild Crower Fire Ball Cam. The Boat was set up in the late 70s and is running fine. I have the orginal paper work if you want I will fax to you just sent me your number......wayne

RaceAeroMini
07-19-2006, 05:06 AM
If anyone has any original paperwork on the race aero system I would appreciate it. Being in Michigan limits my access to folks who know anything about this setup.
I have gotton some new parts (the aluminum banjo bolts on the exhaust manifold) from Carson Brummet but I never thought to ask for any setup information.
Brummet by the way sent the whole set of bolts no charge. Great service and a nice guy to boot.
My fax here at work is:
(248) 542-3411