Okay so, I am thinking that its time to step up in the game.
I am bored of the current mods I have, I think its time to upgrade! My car already feels slow.
I currently have 3k.
I am thinking about getting Headgasket, Headstuds, Taking out the 2.5" pulley, switching it for a 2.9" and and leave the meth.
I will probably be boosting like 15lbs with the 2.9".
However I will probably be able to run like 25 degrees of timing with the 30 70 meth windshield washer fluid. (right now I cant get more than 21 or ill get knock, im thinking its because of the boost)
Now my question is,
Would I have to lower the timing if I want to run a say a 75 shot.
So My future mods will include.
On top of the ones I already have,
75 shot, headgasket, headstuds, Spec stage 3clutch, and about 21 degrees of timing on 30 70 windshield washer fluid.
Im thinking that should put me around 350whp and like 300wtq.
What do you guys think..................
I mean, the motor wont run hot at all, its actually gonna be running pretty cool.
What do you guys think...................................

 

you will have to back timing off. hypereutectic pistons do NOT like nitrous. id say drop the timing 5 degrees across the board of the area you are going to spray. normal timing deduction is 2 degree's per 50 hp applied.

i never ever followed this rule. i just added soem 110 octane and cranked the timing. but thats me, im silly like that. how ever, i have not sprayed a force inducted car.

 

soI guess there really isnt a need for meth then. Will I have to run like 18 degrees of timing and then ill be okay for the nitrous.

 

whats compression on these motors.. i think its like what.. 9:1? if you run nitrous.. how big of a shot are you thinking of b/c you will be fighting that..


2.9.. im hitting around 16.5-17#atm

 

compression on these motors is 9:5 1.

75 shot after headgasket and headstuds.

 

hm.. you will probably be alright.. but i wouldnt do it buts thats just me.. if you were gonna go toward nitrous as your power maker.. i would probably buy 10.5:1 diamon heads and drop the pulley to > 3.x and run a larger shot.... thats what you gotta decide pretty much... Blown cars need low compreesion.. Nitrous cars want High compression.. so you gotta compromise.. or drop the boost a good bit and make up more in giggly juice.. bui have never built a 4-cylinder motor and im kinda suprised we are at 9.5:1 so.. ditto..

 

compression is irrelivant on forced induction vehicles anyways.


thats a whole nother battle i don't feel like fighting right now.

anyways. when on the juice, there isn't a need for the water injection. one or the other, hell you can wire up the master switch to shut off the water injection when the nitrous is armed. just a relay trick here and there. or do a three way switch. center being off for all, up being water on, down being nitrous on. this way they are not all on at the same time

 

You're right about the nitrous, but don't forget the boost. With 9.5:1 compression plus the final cylinder pressure when boost is added in, I think it would be good. If he went 10.5:1, plus boost, plus nitrous, we're talking some high cylinder pressures (Not a bad thing, but definately something to think about; at least he has the studs and headgasket).

Personally, if I were to run nitrous in a similar setup I would use stock compression forged pistons (Not too high, not too low), 3" pulley, and 50-75 shot. The less nitrous, the more boost you can get away with and vice versa (as far as mechanical strains due to pressure). IMO, using the stock compression (middle ground) will be good because then your compromisation will come with the boost and nitrous, which will allow adjustment without tearing into the engine at the same time as it simplifies one of the variables.

I also would highly recommend getting a cam ground specifically for your application because you will have alot of exhaust to expell. If you think about it, you'll have nitrous cooled boost entering your intake, it will find it's way in for sure; all of the exhaust exiting on the other hand needs a well paved highway to truck through via your cam profile.

 

True, a good tune will let you get away with more than you'd think.

 

nod.. but i was thinking reverse the main power adder and raise compression.. we know the m62 is pretty much out of good efficiency over like 16 lbs.. and we know on avg we get approx 6-10hp/tq for each decrease in pully size.. so boost stupid low.. like 6-8# but build high compression and make up all of that boost power wiht a larger short (100-125).. maybe i just didnt come across what i was saying well.. basically.. a Nitrous car with an added supercharger

 

yeah I know, I cant remember when it was the last time I actually sat down and took the time to tune my car right, Im just too lazy and its a long process I dont feel like going through. lol.

 

thats just insane man, Crazy how you pulled that off!

 

75 shot with a 2.8 got me 307 WHP, with timing you might get another 10-20 HP (depending how much you add and what octane gas you are running.

You will need 100 shot before you break into 350's

 

i was running 16 psi, 22 degrees, no knock, and 91 octane.



now i have no idea, im just lazy

 

No, I understood what you were going for perfectly. I was just stating the inverse. Both ways would work; like I said, less boost more nitrous, less nitrous more boost, and dial in the compression ratio to a comfortable level.

 

the thing is that, in these cars, more boost wont really mean nothing with the M62, so we need more nitrous than boost.

 

anybody have any idea how much it would be to install a headgasket and headstuds.

 

A local shop wanted $680 , so I did some shopping and got a GM tech...he did mine on the side for $400.