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I have a 40,000 mile ho motor that I tore down and fly cut the pistons so I could throw some Vic jrs on there. I rebalanced and installed arp hardware everywhere. It is a blow through. I struggled with all kinds of ignition problems with the digital 7, and the CSU carb needs a bit more tuning for a momentary bog but it’s pretty close now and I feel like I won’t be wasting a ton of time on the dyno now when I go. I know people have gone higher but it seems 450rwhp is the line not to cross. I am currently making 7-8 lbs of boost and I’m running 22 degrees of timing at full boost. Cam is a nxhr282. 560 590 lift on a 112. Afr is 11.1 under wot. When I dyno it I was going to jet it closer to 11.5-11.8. I want to purchase a smaller pulley to make around 10 lbs but I was told not to do that and I should drop my timing down to 20 to be safe. Could I really be making 400 plus at the wheels right now? I have not taken it past 5000rpms yet and don’t plan on it seeing 6000. Hp numbers for people’s combos are all over the place. Do I need to get more conservative on my timing and leave the fuel there until I hit the dyno? Or should I get the fuel closer to that 11.5:1. Grab the smaller pulley?
 

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Discussion Starter #2
Quick note here. In California. 91 octane.
 

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it really depends on what the engine likes.

Theoretically, 11.8 should be fine on 10 pound boosted fox. I prefer to go 11.5 or even 11. For one it gives me a bit of a buffer, and the other reason is because I feel mo better about all of the cylinders getting enough fuel. Kinda like the Coyote engine that gets 2 less degrees of timing on number 8, i feel better knowing number 5 won't lean out on my fox.

I am running 24 degrees with my combo. I have a snow kit though.
 

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I’m with you. Like everyone else I want it all. Cam and heads are a bit big and is going to want to spin above 6000 but I don’t want it to. Trying to find the safe middle ground. How much boost are your running that with meth you are running 24? Stock block? What’s your max rpm?
 

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I’m with you. Like everyone else I want it all. Cam and heads are a bit big and is going to want to spin above 6000 but I don’t want it to. Trying to find the safe middle ground. How much boost are your running that with meth you are running 24? Stock block? What’s your max rpm?
In this heat, it is right at 9. In the winter, it will creep on up to 11. Seeing how my car is on stock suspension with just some subframes, I may even back it down a bit in the winter. I can feel the rear-end bind up in 3rd gear in the main tq curve...kinda scary on a street tire.

Yes, 24 with the meth. It could maybe handle it without but, this is a daily and i'm not trying to roll the dice anymore than I already am. It is a stock block. My MSD a9l has a 6 or 6200 chip in it but, i can feel it pulling timing at 5500. Once I feel the bump at 5500, I shift and it drops back to right into peak tq around 3800.

I haven't always ran it like this. I put 50k miles on my combo below with an sct professional tune. It had 21 degrees at 3500 and 20 at 5000 in the wot table. Those few degrees made a whole world of difference. If I get some dyno time soon, I may even be surprised.
 

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oh and don't rejet just yet, 11.0 is going to lean out when you add a degree. If you add two, it may lean out more than you like. So I would try the 1 first. make sure you have your combo pulling timing with high act's. The high act's will get you at 24 degrees
 

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just for reference:

I have been playing with the methanol on the car, making it smoother coming on instead of bogging. I overshot the mark at having it kick on at 4k. Went back and looked at the log and had 24 degrees around 3800 with no meth. My iat's never rose. they stayed right around engine temp @ 172 and 174. This was with 93 octane.

It is fairly hot here today. 94 now with 52% humidity.

granted it did speed up after peak tq, when the meth kicked on. Which is the opposite of what it felt like coming on earlier.
 
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