Small tune

Looking for a 20 to 25hp tune... I'm using a super power shot plate and would like to pick up a couple tenths... last year Drag week the heat was a 100+ and in the finial bracket race they take a tenth away from your average... My average was 11.62 and they dial me at 11.52 and in the heat was running hi 11.60's... would be nice to have that small tune to pick up the differents

We run a digeset box with ours to run the h/u index class. Other wise you have to some of the very small jets in the 20's. Like goes in a fogger. Start adjusting from there. Never used anything that small but I'm sure it would work.

Question, if they take a tenth away from everyone, and all the cars should slow down in the heat, would it not come to consistancy of the cars, and driver? I would personally be scared to breakout on the nitrous, trying to shave a tenth or two. I may be totally off base, with my question, just curious. I think the smallest fogger jets are around .020 or .024, and would make closer to 40 or 50HP, if a 48-50 pill is 100-125HP? If you go this small, make sure you have good clean nitrous and fuel filters, as the micro jets can stop up easy with a fleck of dirt.

A single 20-22 would be pretty close to 20-25 shot. Maybe Steve will chime in but that is a guess based upon what a fogger flows in lbs per hour with those jets.

That is very well possiable. I was dividing the nos jet's from the 125 hp power shot by 2 as a base. Most of those number's, I think were based on a stock 350, so it should be alot less on a warmed over big block.

supervel45 wrote:That is very well possiable. I was dividing the nos jet's from the 125 hp power shot by 2 as a base. Most of those number's, I think were based on a stock 350, so it should be alot less on a warmed over big block.

Cubes don't matter with nitrous on these small shots. You can't just divide by two. Think of it this way, you have a 2" water hose and a 4" water hose. Does the 4" only flow twice as much? No.

I know, it's justed a guesstimate. He have to experiment anyway, to fine tune. Do you think he can dial it into a teenth?

I do know small hits make a lot of difference,, I use a tune from Monty Smith that he called 50hp 42n 36f 5.5fp 30* total timing... that tune drops my ET .5 and the 125hp tune drops .8... that tune is 65n 52f 5.5fp 28* total timing.. I thought of using my digest and only spray a 50hp couple seconds and play with that

quick 52 wrote:I do know small hits make a lot of difference,, I use a tune from Monty Smith that he called  50hp 42n 36f 5.5fp 30* total timing... that tune drops my ET .5 and the 125hp tune drops .8... that tune is 65n 52f 5.5fp 28* total timing.. I thought of using my digest and only spray a 50hp couple seconds and play with that

                                                                                                                                        I have always wondered about the actual horsepower, versus jet size, in relation to cubic inch and volumemetric efficiency of an engine. I feel like the horsepower ratings on nitrous jets, or tunes as they are called now, are somewhat genetic, or ballpark. If they where taken on a dyno on the engine they are used on and in a certain tune, grade of fuel and atmospereic condition, then I would believe the amount housepower that they add. You said that you wanted to pickup .1 tenth of a second, with the possiabilty, of a breakout, in a serious competition. I would test this idea quite a bit first, before I lined up for any money, myself. It just adds to many more varibles to the car for consitisy, in my opinion. I would slow the car down a little from the start of the rounds, through timing, or some other method, and then dial in the tune you took out when the final round comes up, if you can work it that way.

quick 52 wrote:Looking for a 20 to 25hp tune... I'm using a super power shot plate and would like to pick up a couple tenths... last year Drag week the heat was a 100+ and in the finial bracket race they take a tenth away from your average... My average was 11.62 and they dial me at 11.52 and in the heat was running hi 11.60's... would be nice to have that small tune to pick up the differents  

You said final round of the race. What if you put a 150-200HP shot, with a momenty with switch, and used it 3/4 or so, towards the end of the track, and only enough to pull a fender lenght, if necessary, or cross the finish line first? I know this is a totally different stratigy than you are wanting, and is it even workable? I am not familar with drag week rules, but I am curious if this could work? If the other car is spraying, and sandbagging, I could see it causing him to breakout, as well as you breaking out also. The idea you proposed, and the ideas, I suggested, are fancy forms of sandbagging, and reverse sandbagging, in away, just as changing you dail in the final round to keep it interesting, in the quise of fairness I think. It would seem that it would be better to have a big shot at end track that you could cross the finish line first with, even if it meant the possiablity breaking out, than depending on a tenth of two from the start, that may cause consistacy problems, and can't be turned up to cross the finish line first, if need be? Let me know what you think.

supervel45 wrote:

quick 52 wrote:I do know small hits make a lot of difference,, I use a tune from Monty Smith that he called  50hp 42n 36f 5.5fp 30* total timing... that tune drops my ET .5 and the 125hp tune drops .8... that tune is 65n 52f 5.5fp 28* total timing.. I thought of using my digest and only spray a 50hp couple seconds and play with that

                                                                                                                                        I have always wondered about the actual horsepower, versus jet size, in relation to cubic inch and volumemetric efficiency of an engine. I feel like the horsepower ratings on nitrous jets, or tunes as they are called now, are somewhat genetic, or ballpark. If they where taken on a dyno on the engine they are used on and in a certain tune, grade of fuel and atmospereic condition, then I would believe the amount housepower that they add. You said that you wanted to pickup .1 tenth of a second, with the possiabilty, of a breakout, in a serious competition. I would test this idea quite a bit first, before I lined up for any money, myself. It just adds to many more varibles to the car for consitisy, in my opinion. I would slow the car down a little from the start of the rounds, through timing, or some other method, and then dial in the tune you took out when the final round comes up, if you can work it that way.

This is why we flow systems. This is actually a lot more simple than people make it out to be. This is just basic stoichiometry involving some simple molecules and once you know how much oxygen is being released and fuel being added, saying you have enough ignition, then the actual horsepower is easy to figure.

The faster your car is on the engine , the more N02 it takes to make the same drop in E.T.

My car runs 5.40's on engine and a 100 hp shot hardly does anything to the E.T.

Does it improve your 1/4 mile ET ?

Never tried that............... I'm already turning to much through the 1/4 now.

IDT-572 wrote:The faster your car is on the engine , the more N02 it takes to make the same drop in E.T.

My car runs 5.40's on engine and a 100 hp shot hardly does anything to the E.T.

I have had the same experence also. I was always told an engine, with high VE, that runs hard , will take more N20 to make the same difference than a less efficient VE engine. I have a turbo/super charger design book with some serious math caculations, that if every variable of the engine combo was plugged into, and they where correct, would give you a pretty close HP number. On a 5-600HP engine, 25 HP is splitting hairs, so all the input data on your combo ( the physical engine you own ) would have to be pretty exact. I personally don't care what the exact HP is, I just use jet sizes and HP numbers a reference, and starting point. The TUNE is what counts, and not killing or wounding the engine, is what I worry about.