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Back from the dyno, out of timing and boost.

94GrandPrixSE

94GrandPrixSE

New member
Just got back from the dyno, it Made 288WHP and 288WTQ on pump gas at 17 degrees of timing (on a mustang dyno witch is about 30WHP and WTQ LOWER than a dynojet so lets just call it (320 lol). I'm pretty happy with the results but im aiming for 350 so I can sleep at night. I know everyone is going to say E85 but its a 20min drive and don't want the hassle of it all.

So first off im pushing the limits of my LQ4 MAF, im at about 11,300hz at the highest. Based on my research I can do an AFC but is there any downfalls? How do I tune for that? Theres a fixed one from ZZP looks simple to use, any thoughts? Im running a 3.0 pulley at 10.5PSI with no signs of real knock.

Secondly, 17 degrees is the most timing I could add without my WTQ dropping substantially. I found this disappointing as a see people run a ton of timing on these motors. I have tiny blips of kr but nothing over .5 (second gear pull). All my AFR's are dialed in.

Lastly, I just ordered a water/meth kit from AEM. Since I don't have the luxury of E85 I want to squeeze every HP i can out of this thing without having to go turbo. I know how difficult that is with all the parasitic loss of these blowers.

Any advice to help me get to that 350 mark would be greatly appreciated.
 


Those are good numbers.
LS7 Maf is an option too. Make sure you have the correct nozzle(s) for your setup.
 
Buddy mines going e85 he bought a 55 gallon drum to do it from and his own pump. What's your build list and mods?
 


The fixed afc works well. All you do is scale back your maf table. The only disadvantage is less resolution on the table, but it shouldn't affect you too bad with the fixed acc.

My biggest suggestion is to get some 130# springs. The 90's you are running, are too small for your cam and pulley.

If those don't get you where you want to be, you can work on making your intercooler more efficient.
 
the biggest problem with your dyno numbers is the fact that you did the pulls in 2nd gear. 3rd gear is the 1:1 ratio and will give accurate hp/tq readings. and another thing to consider is the 103 plugs, they don't last very long, like 3000 to 5000 miles.
 
Correction it was third gear pulls some reason I typed second.
Thats a sacrifice I'm willing to make for the 103s, I don't put more than 3000 on it a year so works out alright.
 
94GrandPrixSE said:
As far as the LS7 MAF goes, its just a matter of sticking that maf in a 4" pipe, re pin, and use Z06 MAF tables?
Click to expand...

LS7 MAF 15865791, Spectre 4" housing 9705, get a coupler and a MAF flow screen.
yes, it can be repinned. as far as the table, I have one for a 3800 if you need it.
 
GTPpower said:
The fixed afc works well. All you do is scale back your maf table. The only disadvantage is less resolution on the table, but it shouldn't affect you too bad with the fixed acc.

My biggest suggestion is to get some 130# springs. The 90's you are running, are too small for your cam and pulley.

If those don't get you where you want to be, you can work on making your intercooler more efficient.
Click to expand...

The 90#s being enough is definitely controversial. They have a very fast ramp rate and have proven to be very effective in the 3800 world. The biggest downfall is the ramp rate beats up the chains and dampeners. Luckily for me I pull the engine every season at least the last 2 and this winter again for a TEP trans so I do all that maintenance then.

As far as intercooler efficiency, you mean heat exchangers? I monitor all temps post blower and IC and under cool conditions add timing to the IAT tables or decrease them when hot just like an external IAT setup (just higher numbers) point being its running at 120ish degrees under boost which i find pretty decent. That should go down substantially with the meth.
 
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Javi said:
LS7 MAF 15865791, Spectre 4" housing 9705, get a coupler and a MAF flow screen.
yes, it can be repinned. as far as the table, I have one for a 3800 if you need it.
Click to expand...

Is that just a 07 Z06 maf table basicly? How much headroom will I gain over the LQ4?
 
SgtMarshal said:
the biggest problem with your dyno numbers is the fact that you did the pulls in 2nd gear. 3rd gear is the 1:1 ratio and will give accurate hp/tq readings. and another thing to consider is the 103 plugs, they don't last very long, like 3000 to 5000 miles.
Click to expand...

doing a dyno pull in 2nd or 3rd gear won't change the measured power significantly. Regardless of the gear, a chassis dyno is measuring the horsepower delivered to the drum / rollers, and deriving a torque value from that power measurement. In a 2nd gear pull you can run up to engine redline at a reasonable wheel speed, and probably see peak HP. The difference in 3rd from 2nd is that you have a more constant load on the engine to run through, maybe different powertrain loss, but at the risk of a higher wheel speed as you try to run up to a peak HP number as torque is falling off in the upper RPMs.
 
94GrandPrixSE said:
The 90#s being enough is definitely controversial. They have a very fast ramp rate and have proven to be very effective in the 3800 world. The biggest downfall is the ramp rate beats up the chains and dampeners. Luckily for me I pull the engine every season at least the last 2 and this winter again for a TEP trans so I do all that maintenance then.

As far as intercooler efficiency, you mean heat exchangers? I monitor all temps post blower and IC and under cool conditions add timing to the IAT tables or decrease them when hot just like an external IAT setup (just higher numbers) point being its running at 120ish degrees under boost which i find pretty decent. That should go down substantially with the meth.
Click to expand...

I ran 90# springs for a year or 2 with the xp cam. I was always chasing kr problems and just suffered from a lack of power. As I started to learn more about valvetrain control and geometry, I took a closer look at my car. It was really easy to see how bad the valves were floating by watching the boost gauge and then comparing map vs maf. If kpa is increasing and the maf has stopped increasing, you have valve float. No one recommends running 90's with the xp anymore. Yeah, they used to, but that was before we found out how much power you pick up from heavier springs.

As far as the intercooler, you probably won't see much of a gain on the dyno. But on a 1/4 mile pass, I'd bet your temps are creeping. A better pump is needed to keep the fluid moving through. (The flojet people use doesn't flow anywhere close to enough.)

Your next upgrade would be the heat exchanger, but if imagine the frozen boost unit is pretty decent.
 


130's seem to be a bit much for that lift, no?
XP 212/224 .325/.335 116
x1.65 = .536/.552 Lift

Is there a lift height which prescribes certain spring rates? Not being a jerk, just a question I've looked for and not found definitive answers for, lol
 
GTPpower said:
I ran 90# springs for a year or 2 with the xp cam. I was always chasing kr problems and just suffered from a lack of power. As I started to learn more about valvetrain control and geometry, I took a closer look at my car. It was really easy to see how bad the valves were floating by watching the boost gauge and then comparing map vs maf. If kpa is increasing and the maf has stopped increasing, you have valve float. No one recommends running 90's with the xp anymore. Yeah, they used to, but that was before we found out how much power you pick up from heavier springs.

As far as the intercooler, you probably won't see much of a gain on the dyno. But on a 1/4 mile pass, I'd bet your temps are creeping. A better pump is needed to keep the fluid moving through. (The flojet people use doesn't flow anywhere close to enough.)

Your next upgrade would be the heat exchanger, but if imagine the frozen boost unit is pretty decent

Did you test your spring pressure after putting some miles on the 130#s? I remember Will saying this My personal experience with 130# CompCam in my own vehicle, when I had the springs tested during a head rebuild, the springs had weakened to 115# at 1.80" when they should be 130ish. I couldn't quote the mileage but it was roughly a year of service time. Very disturbing so I never ran them again.
Click to expand...
 
94GrandPrixSE said:
GTPpower said:
I ran 90# springs for a year or 2 with the xp cam. I was always chasing kr problems and just suffered from a lack of power. As I started to learn more about valvetrain control and geometry, I took a closer look at my car. It was really easy to see how bad the valves were floating by watching the boost gauge and then comparing map vs maf. If kpa is increasing and the maf has stopped increasing, you have valve float. No one recommends running 90's with the xp anymore. Yeah, they used to, but that was before we found out how much power you pick up from heavier springs.

As far as the intercooler, you probably won't see much of a gain on the dyno. But on a 1/4 mile pass, I'd bet your temps are creeping. A better pump is needed to keep the fluid moving through. (The flojet people use doesn't flow anywhere close to enough.)

Your next upgrade would be the heat exchanger, but if imagine the frozen boost unit is pretty decent

Did you test your spring pressure after putting some miles on the 130#s? I remember Will saying this My personal experience with 130# CompCam in my own vehicle, when I had the springs tested during a head rebuild, the springs had weakened to 115# at 1.80" when they should be 130ish. I couldn't quote the mileage but it was roughly a year of service time. Very disturbing so I never ran them again.
Click to expand...

No I didn't. They were older comp springs. I put I think over 50k on them, and never had a float problem again. It's going to depend a lot on the quality of the spring you buy. I wouldn't buy comps anymore. Pac and Manley seem to do well.
Click to expand...
 
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