vortech 20psi +nos 50shot

[tpapenberg]

Guys I have a 97 cobra bult motor 8.8CR. It has a vortech t-trim intercooled. My IAT2 are around 125 degrees all the time. Sometime they spike to 150 on a 1/4 mile run at 20psi 6500rpms.

I installed a dry fan NOS nozzle about 6 inches away from the TB and after the IAT2 senser. I did becuase I didn't want the NOS to affect the air temp reading. I installed a 50shot in the nozzle and by pressure is at 900lbs at the NOS tank. I will richen the afr from 3 - 6.5K to 11.5:1 so when the spray hits it will be a AFR of 12 flat.

I use SCT PRP to tune my car. it runs about 16 timing at 15psi 5700rpms and 14timing at 20psi at 6500rpms. It's running 91 pump gas at a AFR of 12:1.

Here is the question. Is it cool to spray that 50shot from 3K - 6500rpms to help cool down air temps? Also, do I need to retard timing or is the cooling affect going work for me and my timing will not be affected?

Im kinda new to nitrious so Im not sure how 50shot will react as far as denotation on 91pump and 15 - 20psi.

 

[50_Dave]

kaboom!

 

[5.4 speedster]

of course it's going to lower your inlet temps big time but i am thinking that you will see almost double what the shot is rated at.

thats a pretty small shot... i doubt you will need to retard the timing

 

[KingCobra10Sec]

I'd raise that octane buddy

 

[04svtspray]

I'd raise that octane buddy

+ a million

 

[tpapenberg]

I have tested my old config with 16degree timing , 16psi with IAT2 of 130 (91 pump). I then put a 75shot on it. worked great. Plugs look new.

now upping to 20psi and 50shot on 91 is my goal.... possible ? Thinking on pulling 2 -3 degrees. I will be using a 50 shot instead of a 75 in this setup.

The things I have going for me is my intercooler, 8.8CR and knock sensers, able to retard timing.

Im sure I will get the best possible HP out of a higher octane but the focus here is pump gas 91 octane.

Thanks for your responses!

 

[oscareltemblo]

kaboom I second that.

 

[tpapenberg]

Since its a vortech the 20psi is the prak psi at peak rpm.

3K - 4psi
4K - 8psi
5K - 12psi
5.7K - 15psi
6500 - 19psi

Im thinking on spraying the shot in the 3K - 5K range when the boost is between 4 and 12. That should give me a good boost for the boost

after 5K im thinking boost only and cranker up to 6500 to reach 19psi. My shift point is between 6 - 6.5K so I will not be pushing 19psi ALL the time.. just at peak / peak.

91 octane.

 

[RixSikcobra04]

First of all, I think that's a great setup. That 50 shot is gonna really wake up the slight low end tq loss of the Vortech. As someone already said, it'll be more like a 75-100 shot with the blower. I got 194 rwhp/313 ft lbs with a 150 shot on leaded 110 eek: .

With that said, dude, this setup is already(IMO)pushing the envolope with 91 octane. Nitrous does NOT need/like alotta timing and it loves octane.

Power tune your ride(which it seems you've done), reduce the timing by 1-2 degrees for that 50 shot and PLEASE add a litttle octane. I'd run 100 octane with that setup myself...you will not be dissapointed with the results. You could probably get away with a little less, but why chance it. Take it from me, I've been there/done that when it comes to tryin' to get away with 91 and nitrous. I found, no matter how hard I tried to stay with 91, it became clear that n20 and 91 just don't go well together....period. My NEW motor will never see less than 100 octane seein' as how I love nitrous.

 

[tpapenberg]

Currently I tuned it to the point of 1 degree retard before ping at MAX load from 2K - 6K. I only ended up with about 18 (3.5K) - 14degrees (6K) of timing. This was with 19psi and 91octane. I did not add in the 50shot of not yet. The engine sounds awsome as is and I need to get it on a dyno to be sure im gettings all I can out of it. The plugs are ar94's and the AFR is 12flat. There is a very very slight blue that is on the ground straps that travel a little past the 90 degree bend. I think thats good right?


Later when it cools down I will dyno this car with the 91 to finish the tune and keep off the NOS. Then I will retune the car with 100octane and see what happens with boost, more timing and the 50shot NOS.

 

[RixSikcobra04]

Currently I tuned it to the point of 1 degree retard before ping at MAX load from 2K - 6K. I only ended up with about 18 (3.5K) - 14degrees (6K) of timing. This was with 19psi and 91octane. I did not add in the 50shot of not yet. The engine sounds awsome as is and I need to get it on a dyno to be sure im gettings all I can out of it. The plugs are ar94's and the AFR is 12flat. There is a very very slight blue that is on the ground straps that travel a little past the 90 degree bend. I think thats good right?


Later when it cools down I will dyno this car with the 91 to finish the tune and keep off the NOS. Then I will retune the car with 100octane and see what happens with boost, more timing and the 50shot NOS.

Your ground timing seems to be right based on your ground strap:thumbsup: .

If I were you, I'd stick with your current timing profile(maybe pull a degree or 2 throughout the band), add some 100 octane and a 50-75 shot, and hold on. The 100 octane will barely(if at all)hurt your perfomance off the spray. N20 will net ya ALOT more gains than just increasing timing for power.:burnout:

 

[tpapenberg]

Do you think if I mixed 91 and 110leaded 50/50 to get 100octane?

Do those fuels play well together?

$2.50 gal for 91 + $6.00 gal for 110. = 8.50 /2 = $4.25 per gal for 100octane. not too bad for daily driver...

 

[ogbatman]

kaboom I second that.

I'm with the big bang theory.:rockon:

 

[spyder1337]

I'm running a d1-sc on a built 8.8-1 cr 4v with 20-21 psi at 6k (valve springs are floating) 17.5 degrees of timing on 93 pump gas, hitting it with a 100 wet shot on 110 octane 19 degrees of timing. I would say you're brave to hit the car on pump gas on top of the blower.. playing with fire man.

 

[white98snake]

Hmm yea up the octane and pray

 

[tpapenberg]

I'm running a d1-sc on a built 8.8-1 cr 4v with 20-21 psi at 6k (valve springs are floating) 17.5 degrees of timing on 93 pump gas, hitting it with a 100 wet shot on 110 octane 19 degrees of timing. I would say you're brave to hit the car on pump gas on top of the blower.. playing with fire man.

If your at 20psi with 93 at 17.5degrees then Im just as safe with 20psi at 12 degrees (120 - IAT2) on 91 octane. So it is being done as far as boost and pump gas.

As far as a 50shot. Well, yes I would have to say im playing with fire specialy with 91 octane. I know the 50shot helps cool the IAT temps alot and gives a little kick. I did it at 16psi, 91octane, and a 50shot from 3 - 6.5K and it gave me about 60rwhp extra. My timing was at 16 - 15 from 5K on up. I might of been living on borrowed time but spark plugs and EGT's looked real good for what I was doing. I then changed pulleys to spin the SC faster. (So i might not need the NOS shot)


Now im at 20psi at 6.5K.

I think I might hold off on the NOS and just dail in the timing on the dyno for the 20psi at 6.5K. Save an engine What kind of octane would I need to get my timing up to 23 since that is the MBT? I will NOT be using Nitrious for the tune.


PS. My timing curve for 91 pump at 20psi(6.5k) was 2K - 15, 3.5K - 18, 5K-15,6.5K-12. Worked like a charm with 8.8CR and IAT2's below 130. AR94plugs.

 

[RixSikcobra04]

Do you think if I mixed 91 and 110leaded 50/50 to get 100octane?

Do those fuels play well together?

$2.50 gal for 91 + $6.00 gal for 110. = 8.50 /2 = $4.25 per gal for 100octane. not too bad for daily driver...

You'd have 100 ocatane on a 50/50 mix of 91/110 leaded. Get Sonoco leaded 110, it has an essentially identical specific gravity as pump gas(about .725). That's what I do...I am actually closer to about 106 octane on a regular basis since I seem to be constantly putting 110 in. I run a 150 or 175 shot so I need the little extra detonation protection. It's simple, dude...I know it's hard to retard timing because you could lose a tiny bit of hp BUT just know you will gain tons more on the spray. 100 octane and 2 degrees tard and your car will be REALLY happy with that setup. You're daily drivin' it so you'll be sprayin' when ya race, right?...you'll hardly even notice the difference off of the spray.:thumbsup: