6 degrees retarded
 

I realize that this is a difficult question, but I am just after a general idea. If a motor makes ~600 hp at 34 degrees and that is found to be the most hp, how much would the motor loose retarding it 6 degrees, for nitrous lets say.
Is there any other info that would help?

Thank you

Re: 6 degrees retarded
 

Adam

If thats where the engine makes peak hp normally asperated usually you need to take engine time away to keep you out of the detination factor,when using nitrous.Detination occures ATDC usually between 10 and 14 degrees ATDC JMHO from my findings.

Running nitrous usually you start safe and tune by watching the spark plugs and reading the heat and fuel mixture to reach the "sweet spot"

I am not debating if I should take timing out or not, I am just curious what effect it has on hp before you throw the nitrous at it. What if the motor made max hp at 34 and you dropped it down to 28 for nitrous and left it there rather than setting it back and forth. How much power would you loose?

Thanks, Adam

That i can't answer,I don't know how much hp you would lose,and it would depend on how and when the nitrous would come on into the run.

Then running around the pits having the timing fixed at 28 it may be a little sluggish,I would think you'd want to run the engine with some type of a timing retard when the nitrous was activated,not just fixed.

Sounds a little complicated the way you want to run this engine,you could get into trouble doing things this way,you need to start safe and work your way back up to optium hp,the Et's and MPH will prove this.

Tuning nitrous requires small movements,with timing,just not guessing you got it right,you are going to get in trouble the way you want to do it

firestone, tom is right work your up on the tune he's been doing it for a long time and know's his chit. i can give you some examples from yrs of dynoing but in no way is it to be use as every engine does the same thing. my 555 in my chevelle has 850ish hp with 38deg of timing and with 30 deg of timing it made 730hp. the engine in the duster is a 410cid and it made 500hp with 37deg of timing and 420hp with 30deg of timing. but here is the big differents the engine in the mustang was a 420cid sbc with 34deg of timing it made 900+ and with 30deg of timing it made 690hp.

Find someone with a chassis dyno in your area that has a wide band A.F. meter.you can get close on jetting and timing with only a few runs and far less chance of piston damage.leave your timing at 34 and get a retard device to work with the N20 you will be much happier.Bill

I understand what you are asking. You dont want to have to be adjusting the timing all the time from running N/A to nitrous right? You will lose power by retarding it N/A. I had a bbc and I had it timed a 36 and bumped it up to 42 and the car picked up nearly a tenth so it will definatley slow down. If you sont want to have to manually reset the timing when you want to use nitrous I would suggest buying a retard module and then you can just change the chips and dont have to mess with the distributor.

Impossible to answer question.

Each engine will exhibit it's own peculiar charastics pertaining to timing and timing changes.

Some are extremely timing critical and others are not. An example is one I tested not too long ago that was set at 31 deg in the initial testings. After we got some color in the plugs with numerous jetting changes we bumped the timing up by 3 degreees and lost considerable hp and torque. We moved it down by two deg and it came alive with the best nubers in all rpms. We moved it down two deg and lost much power in hp and in torque. REsult is that it wantted what it wanted and even two degrees ruined it either direction. On the other hand I have seen engines that respond sloyly to timing changes and even a 4 to 6 degree difference doesn't change things a bunch.

My suggestion is the same others said. Get the motor to where it is happy and by electronic retards only retard it when using nitrous.

Ed

There is a few problems with it. First off it is a rule of thumb to run 1 degree colder on plugs per 100 HP of nitrous. That along will affect performance when running N/A. The second is you will need to drive to the pits with this setup on motor. If you tow it you still need to start, roll to the water box and so on. Since the motor is using colder plugs it has a tendency to foul the plugs out from running rich. Then after all of this you still need to get on the convertor. This will add to the richness. If you remove more timing it will only effect this process more. When your nitrous activates it could get very ugly (depending on your nitrous level). Personally my motor ran best @ 29 degrees of timing on motor. Below 3000 RPM I would run 40 degrees of timing to keep the plug clean and not load up. This allowed me to drive to the line, do my burnout and get on the convertor very quickly. After 3000 RPM I ramped the timing back in. Remember electricity is faster than anything we know. So dont be afraid from removing and adding timing.. It will be the first thing that happens when the nitrous comes on (if everything is wire correctly). The above example of ramping timing was done with a digital box and I know a lot of people dont have them. But I was just using it as an example of what can be done..

Thanks a lot for all the replys, that helps a lot.

Adam