Were did I go wrong with my engine combo
#1
Staging Lane
Thread Starter
Were did I go wrong with my engine combo
I built an 383 ls1 trickflow 220s Fast 102 intake /tb tsp custom grind cam speced for my engine, 242/250 duration / .365/.353 -.620/.600 @ 113 lobe separation 1&17/8 long tubes and full tsp duel exhaust , yank 3600 stall. 9in with 3:89 gears , my t/a made 448/430 to the ground on a dyno jet , they tuned it speed density , the car feels real gutless driving around, won’t idle, even @ wot car feel like a dog , could it be the tune or is it over cammed? I called BTR the other day and they recommend there stage 4 cam .
Last edited by Rickys2003svt.cobra; 06-02-2019 at 01:13 AM.
#4
Staging Lane
Thread Starter
#5
12 Second Club
I won't claim to be an engine expert either, but I also think the cam is way too big. From what I have seen, the bigger cams make more hp at high rpms, but not much down low. If you are just driving around town, you are not using the "power band" that the cam is designed for. You probably never get the engine up to the rpms where you will actually feel the power. You would need about a 5k stall converter to get that cam up to it's power band.
If it were my car, I'd ditch that monster cam, and go with the BTR stage 2, or maybe stage 3. The smaller cams seem to make more "usable" hp and torque for daily driving.
If it were my car, I'd ditch that monster cam, and go with the BTR stage 2, or maybe stage 3. The smaller cams seem to make more "usable" hp and torque for daily driving.
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#8
12 Second Club
I don't care how good of a tuner you are, that car is not gonna idle worth a damn with that much overlap. Your tuner's skills can't compensate for poor mechanical combinations. Get a smaller cam, and you will be able to enjoy your ride. It will probably make more power with a smaller cam too.
#9
Cam is 10 degrees too big and the fast 102 tb is garbage. It's known to have idle issues. nicD knows all about it. A NW TB will have much better idle characteristics and tune easier and a smaller cam will be more make a lot more torque down low and idle nicer. Bigger is not always better.
#10
Staging Lane
Thread Starter
I shifted at 6500 rpms , the only reason I put this cam in is when I called tsp to have a cam that would work good on the street and make good power , and this cam would need a 3500 stall ,
#11
Staging Lane
Thread Starter
Cam is 10 degrees too big and the fast 102 tb is garbage. It's known to have idle issues. nicD knows all about it. A NW TB will have much better idle characteristics and tune easier and a smaller cam will be more make a lot more torque down low and idle nicer. Bigger is not always better.
#12
That cam isn't that big for a 383ci in my opinion, especially with the 3600 stall and 3.89 gear combo. I've seen people run similar cams in H/C/I 346ci engines on the street and those cars were definitely quick so in a 383ci I definitely wouldn't expect it to be a dog? To be honest I wouldn't even expect the idle to be 'super' lumpy with the 113 lsa, let alone struggling to idle and the dyno numbers look a little low for a stroker with nearly all the fruit too - not that I usually pay them much attention but it all does add up. Just my 2c..
#13
Staging Lane
Thread Starter
I don't care how good of a tuner you are, that car is not gonna idle worth a damn with that much overlap. Your tuner's skills can't compensate for poor mechanical combinations. Get a smaller cam, and you will be able to enjoy your ride. It will probably make more power with a smaller cam too.
#14
TECH Junkie
I shift my combo in sig at 7100 rpms and run a Pt4400.
When it acts up is it while coasting or is your foot on the brake?
#15
TECH Junkie
#16
TECH Junkie
Shifting at 6500 your combo has probably yet to peak. That combined with a to small stall and low shift extensions probably are not doing you any favors. Your shift extensions are probably around 5000-5200 rpms.
Now look at your dyno graph and see how much power you're making at 5000 rpms. Probably not much.
I would guess a 3600 was the minimum needed to have good driving characteristics but if you're looking to keep power in the wheel house you need to spin much higher and go with more converter.
Here is what im talking about. My combo with 7100 shift points and 4400 stall.
Now look at your dyno graph and see how much power you're making at 5000 rpms. Probably not much.
I would guess a 3600 was the minimum needed to have good driving characteristics but if you're looking to keep power in the wheel house you need to spin much higher and go with more converter.
Here is what im talking about. My combo with 7100 shift points and 4400 stall.
#17
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When you dynod what rpm were peak tq and hp? Typically a LS with stock length runners is going to peak 4800 and 6300. That will also usually result in numbers like 480/430. Bigger increase in power vs torque. Seems like your power may have peaked early and fallen?
Also what compression ratio?
Also what compression ratio?
#18
12 Second Club
What do you plan on doing with this car? If this is a race-only car, then just keep the cam. It won't matter how it idles or drives if you only need it to go a 1/4 mile at a time. If you plan on driving it around town, and not at the track, then get a much smaller cam. The BTR stage-2 would work well with your other parts, and make more "usable" hp/tq.
#19
Staging Lane
Thread Starter
That one has too much overlap for me, but I didn't build a "race car". I actually drive mine to work almost every work day. There's no way I'd have a BTR stage-4 in my car. The stage-2 is the biggest I would go.
What do you plan on doing with this car? If this is a race-only car, then just keep the cam. It won't matter how it idles or drives if you only need it to go a 1/4 mile at a time. If you plan on driving it around town, and not at the track, then get a much smaller cam. The BTR stage-2 would work well with your other parts, and make more "usable" hp/tq.
What do you plan on doing with this car? If this is a race-only car, then just keep the cam. It won't matter how it idles or drives if you only need it to go a 1/4 mile at a time. If you plan on driving it around town, and not at the track, then get a much smaller cam. The BTR stage-2 would work well with your other parts, and make more "usable" hp/tq.
#20
TECH Apprentice
I won't claim to be an engine expert either, but I also think the cam is way too big. From what I have seen, the bigger cams make more hp at high rpms, but not much down low. If you are just driving around town, you are not using the "power band" that the cam is designed for. You probably never get the engine up to the rpms where you will actually feel the power. You would need about a 5k stall converter to get that cam up to it's power band.
If it were my car, I'd ditch that monster cam, and go with the BTR stage 2, or maybe stage 3. The smaller cams seem to make more "usable" hp and torque for daily driving.
If it were my car, I'd ditch that monster cam, and go with the BTR stage 2, or maybe stage 3. The smaller cams seem to make more "usable" hp and torque for daily driving.