The N/A stock motors do go flat between 2500 and 4000 rpm ... You can definitely tune that out when you go boosted.

I think the JWT C2 cams are better for us. My understanding the guy had FI 3.5 turbo's. I would have used the JWT C1 cams on that engine. You can see the torque curve in the video. It's flat and comes on hard down low. Too much for my liking. He will struggle with traction down low for sure. Looking at your graphs the 3.357 is the reason your dyno graphs read low. Doesn't matter if the car is not in the correct rpm range for the quarter mile. The less shifting is also better for 1/4 mile. A 3.5 diff would be better for you I beat. MA can fix that up for you also with a quick change diff and custom subframe. LOL

The machine shop is working on my engine now. They were honing the cylinders Tuesday last week. Hopefully it will be done by the end of the month. I don't want to travel up that way until after New Years anyway. Way too many people on the road. I will do it if they call and want the car.

My worry is the weather. MA likes to drive test them on the road to double check the tune, etc. This will be a challenge in the dead of winter. Finding good days to do so will be tough.

This build is all new territory for me and I've been making decisions these past 5 years based on research and the technology available at the time.
Tried my best, but it's still an educated guess tho'.

I did consider the 3.5 FD (from the 350z) but it was too close to the 3.692 OEM gears in the car... so I went with the 3.357.
As it was - the OEM 3.692 gears were just about useless launching the car.

I did check out that video you posted earlier - looks like Dynosty did a great job on the build and tune.
One of the things I look back on and regret a little is not going with the 10:1CR.
I had 9.5:1 in the IPP built motor that AAM managed to grenade.
Daelen talked me into going back to the OEM 11:1 CR for their build.
Right now I'm going to live with what I have - been way too long as it is.

The DynoLog Sheet does show a hump in the Torque curve at 4300 rpm, and flat spot in the neighborhood of 5000 rpm.
Will have to see how that works out in real life.
I'm sure/hopng it can be corrected if needed.

11:1 is where you want to be. I wouldn't build a 10:1 engine. No need to with the tuning/fuel we have today. That is old school thinking. Your rear gears are going to move the torque curve up. If you had the 3.69 gears it would be at 4000 rpm. A flat torque curve is what you want. You also have to note the mainline dyno is going to show lower than the dynojet that was used in the video. I think you are fine. Get it on the drag strip and see how it does. That is the real proof.

From my understanding the bigger the overlap the higher the back pressure, which should cause spool to be sooner.

I would put the more aggressive cams on the bigger turbo setup - meaning I would use the C2 Cams with the 3.5 Turbos.

Small turbine = less overlap. Large turbine = more overlap.

It all depends on where you want to move the power under the curve.

Spooler this is very interesting. You're pretty much talking about my build. I went 10:1 with the C2 cams and a bigger turbo. Still tuning it now with Seb but you're absolutely correct with the Cams helping with spool.The 6870 spools faster than the 6266 did by a long shot. Also if I WOT in 6th gear cruising 70 I'll hit 12psi before it hits 4500rpm. I had a problem with traction for 3rd gear WOT logs but switching to R888R's solved that in short order. Just moving on to E85 on Map 1 so pretty soon we'll see how it handles boost and E85. I don't think I'll be done tuning for a bit but as soon as I amI'll be throwing it on some rollers to see where it sits. I've guessed at 800rwhp but after feeling the hits ridiculous boost I'll be content with a 750 on corn and leave it where it sits.

Interesting reading these last posts from you guys ...
I've test driven the car twice now on local roads - When the motor was 10:1 with no cam the torque came on real quick and was flat out to red line. With only a little goose on the throttle and into 3rd gear it wanted to spin the huge M/T's.
It would have been nice if the motor held together.

With the MA-M 11:1 and the JW2 cams it didn't seem that 'touchy' on the throttle.
Both test drives didn't go WOT or over 40mph but I felt the power want to come on.
Brian at MA-M did a short test drive before handing the key over to me.
I heard him lean on it when he got it on to the street in front of the shop.
It sounded good but I didn't get to see it accelerate.

The 71/63's did spool quickly.

Got an email from MA-M today and they are anxious to finish up the build.
Waiting on the 6 point Roll Bar from RPM Rollbars.
Still planning to winter it down there since the weather gets ugly up here in N.J.
The car would only be sitting till spring anyway.

I am sure they are wanting to have it completed. I have had cars sit at the shop for a while myself and the day they leave is a good day. I was glad to see them up and running and on their way. My understanding is they have a lot less space as they did before.

I have experience with this playing with my 04' 5.9 Cummins dually. Swapping turbo's and trialing 2 different cams for Hamilton Cams. It is a little different but still the same.

True, the Z has a shorter wheel base so I can see why you're saying you'd want the spool to move.

Did you ever mention which Xonas you ended up getting?

They are the FI 2.5's. They are a GT30 frame turbo. I don't remember the Xona numbers off the top of my head. They are a custom Xona turbo.

Always good to have a little more headroom! :yum: