PDA

View Full Version : Information on GN engines


summoner
10-16-2004, 12:05 AM
Heya i'm from Aus and have a few queries regarding the engines in the 86/87 GN's

What is the max boost these can run with a stock bottom end on pump fuel, whats the max RPM for a standard engine?

Keller
10-16-2004, 12:39 AM
Heya i'm from Aus and have a few queries regarding the engines in the 86/87 GN's

What is the max boost these can run with a stock bottom end on pump fuel, whats the max RPM for a standard engine?

Aus...trailia? G'day! :cheers:

Everything depends...

Any stock, unopened TR motor with a stock or mild turbo on it will be limited to 15-16 PSI as you run through all gears with a typical street profile chip in it with average 93 octane pump gas. Fuel varies, and some areas only have 91 octane as their top blend. Caveat emptor.

Chips can have adjusted profiles, alcohol injection systems are getting very popular, unleaded or leaded racing fuel is always an option. In a 'race trim' 20+ PSI is not unusual, and 24+ with a more aggressive turbo is not uncommon.

With a stock, untouched motor, 5200-5300 RPM is about all you want to go. Maybe just a hair more, but you run the danger of joining the DOTC - see http://www.gnttype.org/techarea/pictureguides/blocks/DOTC.html for details. If you want to avoid this, and you are planning to be running beyond the high-to-mid 10s (roughly 600 HP range) regularly, you can girdle the bottom end like (http://www.gnttype.org/techarea/pictureguides/blocks/8687girdleblock.html ) which has permitted these cars to go welll into the 9s, or go with a "Stage II" block from the Buick racing program (http://www.gnttype.org/techarea/pictureguides/blocks/38stage2.html) - much more meat.

summoner
10-16-2004, 05:06 AM
thanks heaps for the info :D

we run the same 3.8l engines in our commodores(albiet without a turbo.. boohoo hiss) so i've always thought about a turbo conversion on 1 as a project. At present though I am more leaning towards finding a t-type or GN and importing it into australia as a project car, would be unique here :)

Keller
10-16-2004, 02:35 PM
There are some GNs and Ts in Europe. UK, Scotland, Finland, Norway, Sweden, etc. I had the privledge of meeting up with a few members of our original mailing list while I was in Altrincam, UK on business. Two GNs driving down a urban British street catches some attention. And riding in the passenger's seat of a LHD car in a RHD world caught mine!

There is also a gentleman (Con Liapis, I believe) that lives somewhere is Australia and owns several *RHD* GS' from the early 70's. He ordered some of our videos I had made in PAL format for our friends in other lands. He and his cars were featured in several newsletters from the GS Club of America.

I think a GN or T would be just the ticket for spanking a Monaro or Falcon XR8!

FlyinGN
11-08-2004, 12:22 PM
You can run a whole lotta boost. (25 lbs or so) with a stock bottom end.. As long as you run race gas or an alchy system.. Don't expect the motor to last 100k miles tho lol..

Frank


Heya i'm from Aus and have a few queries regarding the engines in the 86/87 GN's

What is the max boost these can run with a stock bottom end on pump fuel, whats the max RPM for a standard engine?

jsta6
11-25-2004, 12:12 AM
Check out "wheels" magazine, Feb 1987. I have copied it to our clubs web site. Right mouse click and choose "save target as", or "save to disk". It is 8.5MB is size. Check out the engine pic on page 45.

http://www.sftbc.com/files/wheels%20feb%2087.pdf