Isn't a tune/recalibration needed when you move to bigger injectors?
With 405hp on tap, our C5 Z06 project wasn’t exactly suffering for thrust, but with modern factory Corvettes pushing 450+ up to over 700hp, there’s always room to improve when it comes to the get up and go.
Our first stop on the way to more power was an intake manifold from F.A.S.T., widened with a 92mm opening. Currently we’re using the stock 75mm throttle body with an adapter—since we only like to upgrade and test one thing at a time—but the 92mm opening gives us lots of room to derestrict the intake tract down the line.
Installation was fairly simple, if a bit tight. There’s a couple of fasteners toward the back of the engine bay that will take a while to get out, just live with it. Likewise, installation of the F.A.S.T. manifold is straightforward, but snug. The 92mm manifold is about as tall a manifold as you can get under the stock cowl of a C5 without lowering the engine using shorter mounts or modifying the cowl area using a saw and/or hammer. For clearance, you’ll also have to flip the manifold pressure sensor to face the driver’s side of the car, rather than the passenger side. It’s simply a matter of sticking it back into the manifold facing one way instead of the other.
Since we were disassembling the fuel system anyway, we also took the chance to replace our stock 24lb/hr injectors with a set of Deatschwerks 45lb/hr injectors. While our stock injectors could have kept up with the fuel demands of just an intake manifold change, we were future-proofing ourselves a bit with more modifications in mind down the road. Those stock 24s are good for a few basic bolt ons, but don’t give you much tuning room when you start to get into stuff like long tube headers, and especially more aggressive mods like cams. The Deatschwerks injectors are simple drop-in pieces that fit like a glove and ran perfectly right out of the box.
Our reward for this wrenching and a bit of tuning was seven additional peak horsepower and four additional pounds of peak torque (on a very stingy Mustang chassis dyno). The best part of this graph, though, was the broad-spectrum torque we picked up all the way across the rev range. There was additional torque from the beginning of the test all the way through to the rev limiter. That translates into more thrust where and whenever you hit the gas, and we like that.
Isn't a tune/recalibration needed when you move to bigger injectors?
^^^ Like he said, this has to be without tuning right? Numbers seem low, but it is on a Mustang dyno
Can I have the old intake for a challenge car
Patrick said:Can I have the old intake for a challenge car
I asked first on the instagram post...
That's a lot of money for not very much gain
In reply to StuntmanMike :
We did re-tune the car after adding the intake and injectors.
jwagner said:Isn't a tune/recalibration needed when you move to bigger injectors?
'07 MX-5
The answer is maybe. The stock ECM has a bit of leeway, but plugging-and-playing probably won't be a best case scenario.
We tuned both pre-install and post-install. On our car, there just wasn't much there with tuning alone. This could be due to the age of the motor (nearing 100k), or just the factory tune being fairly good to begin with, but we didn't find more than a couple hp with tuning alone.
StuntmanMike said:^^^ Like he said, this has to be without tuning right? Numbers seem low, but it is on a Mustang dyno
A notoriously stingy Mustang dyno, at that.
were any pedestrians harmed in this testing?
That's not very impressive. 2% gain, pretty much all over 5000 rpm. What's the run to run variation look like on this dyno?
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