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Hello, I have an 01 trans am with an ls3 416 stroker. Just got done & put on a dyno & made 380ish to the wheels Which from what I’ve seen 416s usually make 500+. And the guy that tuned it said it’s on a mustang dyno & has a stock ls3 intake & that’s usually what he sees 416s make. But I have a couple friends that have 416s and they made around 560 with a stock intake so I call Bullshit. What do you think? I’ll post all of the details about the car, which I know I’ll forget something so just ask and, keep in mind, I’m deff not a car guru, Still learning.
01 trans am
416 stroker built by Thompson motorsports, which build sheet is in the pictures
Stock ls3 intake
65 or 62 lb injectors
92mm NW throttlebody
ls3 CNC ported heads
T-56 6 speed with monster stage 4 clutch
MWC 9” 4.56 gears
Thank you for your opinions.
Mustang dynos are heartbreakers. LS3 intake good to about 6500rpm (maybe).
My car made 460 on a mustang but ran a 9.91 @ 136. (It takes about 600rwhp to do that) with a LS3 intake.
Mustang dynos are great for tuning (much better than a Dynojet)) so don't get hung up on numbers.
How does the car feel? Either the dyno is reading very low or something is wrong. See if he has other numbers of other cars/combos to compare with. The shape of the graph looks good. Strong tq & the power carries well to about 6750rpm.
How does the car feel? Either the dyno is reading very low or something is wrong. See if he has other numbers of other cars/combos to compare with. The shape of the graph looks good. Strong tq & the power carries well to about 6750rpm.
Well, I drove in a friends trans am with a 416, just to compare and his seemed to pull significantly harder.
That's a healthy cam. Should be at least 470 to the wheels assuming the pushrod length is right and all 8 cylinders are firing.
Time to check the plugs (getting spark on all 8?) heat gun works to see if there's a dead cylinder. If all are firing, time to pull the valve covers and check lifter preload and pushrod length.
What do you mean by 65 "OR" 62lb injectors? You don't even know what they are? So obviously you didn't get them flow matched. Big mistake. Could be your problem right there. If all 8 cylinders aren't running exactly the same, one or two rich/lean cylinders are gonna pull the entire engine down.
Hi there, When I first built my 421 earlier this year I used a stock LS3 intake on it and the truck went 10.80's and was out of air at only 5800. After talking to a few members I switched to a LSXR high hp intake and I'm now running 10.42 and it pulls as far as I want to push it. I traded some torque down low for horsepower up top which is a good trade off on a stroker and my ET reflects that. The stock LS3 intake is a fine piece for stock but a stroker requires more air.
No the Dyno isn't the problem unless the operator put in the wrong inputs. No the injectors being flow matched isn't the problem unless 1 or more injectors flat out isn't turning on. No the intake manifold isn't the problem. When you're down 100 or more rwhp some is majorly wrong like missing cylinders or cam timing is WAY off.
08-28-2018, 10:48 AM
416 made horrible numbers!! What’s wrong? 
