PDA

View Full Version : OS 91 C-SPEC -- compression ratio


Shannon Davis
04-05-2004, 11:15 PM
I have been playing w/ the compression ratio on my C-Specs. Both pumped and un-pumped. It seems to run a lot betterw/ less compression.

I run a viper head and coolpower 30%.

The lower compression lets me run a leaner mixture, and seems to have more power and run smoother. Also requires less tuning.

I think I have been running too rich in order to keep the engine from pre-igniting. It doesn't make sense to me to run the mixture too rich to fix an engine that may have too much compression.

Has anyone else had any experience w/ this????

Al Magaloff
04-06-2004, 05:43 AM
What you're doing is changing the ignition timing. Play with plugs, too.

Shannon Davis
04-06-2004, 07:10 AM
Yea- I know- sort of. I had a long talk w/ a friend of mine- kremlin. He is head of the engine department at Prototype Technology Group- the BMW factory race team. He explained a lot to me-- what do you know??

Thanks Al

kremlin
04-06-2004, 01:05 PM
After having a conversation with Shannon on his C-spec engines. A couple of questions have come to mind.
1)Is a glow fuel engine a compression ignition engine aka diesel?
2)Is a glow fuel engine a catalyst ignition engine: hot platinum / alcohol reaction?
3) Combination of #1 and #2?
4) Temperature of glow wire and pressure in cylinder effect on ignition timing?

If you guys have any input jump in I would like to understand what is going on.


Brian

Al Magaloff
04-06-2004, 06:20 PM
Yes to numbers 1&4.

ttrip06
04-07-2004, 08:20 PM
Yes to numbers 1&4.

The other thing to know about these motors is that nitro does not like to be compressed.

Look around the web for some of the older articles that Bruce Bennett wrote. He was able to make 10 cc (60 size) motors pull as hard as most todays big blocks. 5 years ago.

Look at most of the guys drag racing. Ken J., Ron Lund, and myself are all running motors that Bruce helped modify. These motors as of last years IRCHA were still out running the big blocks. If BB ever gets back to chopper and starts work his magic on the 90's look out.

Later,

Trip.

Shannon Davis
04-07-2004, 11:48 PM
ttrip- is there any way you could find those articles and post here or a link. I know I could do it but have my hands full w/ the site/work right now. If you can help--I THANK YOU IN ADVANCE.

ttrip06
04-08-2004, 07:43 AM
Shannon

Give me a couple of days and I will post them. Its a holiday weekend and I am going to be busy.

Trip

Shannon Davis
04-08-2004, 08:16 AM
ttrip06--thank you very much-- i do apreciate it. I will do some searching also and see what I can come up with- maybe we will get different returns to our searches.

Thanks