[6pack] [TR] Compression boost

[Sally or Dick Taylor]

Rick---The MSD-BTM inition unit works well in retarding the spark timing. This Martel Bros. unit includes a remote control timing adjuster that can be mounted anywhere you choose. One can dial in the amount of retard based on the boost pressure sensed. I.E. anywhere from .5 degrees per pound of boost up to three degrees per lb. of boost. (Max. of 20 deg. of retard)  A vacuum hose connects from a port on the intake manifold directly to the BTM. You can Tee off this line to an in-cockpit gauge, of course.
 Much more reliable than knock sensors, for the TR6.

This sort of tool allows one to dial in a little more initial spark advance for when off-boost, knowing that some safety is there when cylinder pressures "spike"!

Dick


-----Original Message-----
From: Rick
Sent: Monday, June 16, 2008 10:58 PM
To: Jeff Scarbrough, Raymond Hatfield, triumphs at autox.team.net, 6pack
Subject: Re: [6pack] [TR] Compression boost

I have a knock sensor on my fuel injected supercharged TR6. It's mounted
near where the ignition coil once lived but is now disabled. It was very
effective at retarding the timing but because these solid lifter engines are
so noisy it was far too sensitive. Even tuning it's sensitivity back it
would often retard the timing way too far causing the engine to stumble.
Maybe someday I'll look into trying it again, perhaps on the other side of
the engine away from the valve train would work a tad better? As it is now
the engine is 7.75:1 running high test gas with up to 8.5LBS of boost and
timing at times is as far out as 34 degrees and no pinging. Without boost it
would run out to 36 degrees but I worried about burning a piston and
chickened out setting it back to 34 max.

Rick Patton
75TR6sci
rick at pattonmachine.com



> -----Original Message-----
> From: triumphs-bounces+patton=suscom-maine.net at autox.team.net
> [mailto:triumphs-bounces+patton=suscom-maine.net at autox.team.net]On
> Behalf Of Jeff Scarbrough
> Sent: Monday, June 16, 2008 6:12 PM
> To: Raymond Hatfield; triumphs at autox.team.net; 6pack
> Subject: Re: [TR] [6pack] Compression boost
>snip

 >gasoline.  Never pings with mid-range or hi octane gas.
>
> Yes, but doesn't your Miata have a knock sensor that retards the
> timing upon detecting a ping?
6pack at autox.team.net
http://autox.team.net/mailman/listinfo/6pack

http://www.team.net/archive

You are subscribed as tr6taylor at webtv.net