expected more from my set-up
The A/F doesnt look like its tuned for NA. And if you dont know what the timing is, how can you make that assumption? It could be 19 degrees, when it may want 28 degrees.
The A/F doesnt look rich enough for FI but too rich for NA. It should flat line at 13:1. See where it starts to dip, right about peak HP?
Taking a little bit of fuel out of it, combined with getting the timing where it wants to be, hell you could be looking at 15-20 hp.
The A/F doesnt look rich enough for FI but too rich for NA. It should flat line at 13:1. See where it starts to dip, right about peak HP?
Taking a little bit of fuel out of it, combined with getting the timing where it wants to be, hell you could be looking at 15-20 hp.
Isnt tuning all about maximizing your combination? Why dont you start by spending some more time on the dyno, squeezin her? I've found big chunks of HP and TQ in cars that have previously been tuned. Spend some more time on the tune, get it to where you cant make any more, then see where you're at. I have tuned quite a few setups with Patriot heads, and 3 out 4 folks expect more. I don't know what the deal is with them, but they very seldom make GOOD power. That's the rub of a budget head in most cases. At any rate, I would expect 400-415rwhp with that setup based on similar setups on a dynojet.
Since you went to speed density did your tuner make sure to copy the high octane spark table values over to the low octane spark table? Once you pull the MAF off the PCM will resort to running on the low octane table for spark, which greatly retards timing. This could be a very plausible explanation on why you lost power. You need to have the table copied over.
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Since you went to speed density did your tuner make sure to copy the high octane spark table values over to the low octane spark table? Once you pull the MAF off the PCM will resort to running on the low octane table for spark, which greatly retards timing. This could be a very plausible explanation on why you lost power. You need to have the table copied over.
Unless you like to touch up your tune every so often and are OK if your car acts kinda quirky at moments (IAT heat soak, extreme outside temp change, etc, though retaining CL can help) then SD is probably not for you.
There is no perfect SD tune; remember the bias problem and lack of a suitable solution.
Last edited by Frost; Nov 2, 2007 at 01:18 AM.
Besides it takes out one more damn thing that you have to tune, thats why i took mine out, plus it looks better with a nice bellow in place instead.
You wont gain anything when going from good MAF/VE tune to a good VE only tune.
Hard to believe that someone can tune in SD and doesn't know this.... it's not like they are going to be skippng spark tables.
Unless you like to touch up your tune every so often and are OK if your car acts kinda quirky at moments (IAT heat soak, extreme outside temp change, etc, though retaining CL can help) then SD is probably not for you.
There is no perfect SD tune; remember the bias problem and lack of a suitable solution.
Unless you like to touch up your tune every so often and are OK if your car acts kinda quirky at moments (IAT heat soak, extreme outside temp change, etc, though retaining CL can help) then SD is probably not for you.
There is no perfect SD tune; remember the bias problem and lack of a suitable solution.
I dont find it hard to believe at all, there are so many so called "tuners" out there that dont know **** really so i dont doubt that situation one bit.
I never touch up my SD tune really, but I run it closed loop. OLSD is a whole different animal. Once you go open loop it is quirky and needs care from time to time.
1) That cam is small and not exactly designed for high peak numbers, especially HP.
2) You're in the same boat as me with these damn Patriot heads. They just plain suck.
My advice if you're looking for numbers closer to 400/390, swap the cam and absolutely swap the heads. I'm sure all of these guys are right that you will pickup quite a bit by working out your tuning issues, etc, but I don't see much of a reason for making much more than you did on the last dyno you mentioned. You have a baby cam and crappy heads.
For comparison, my car has similar Patriot Heads and a slightly larger cam (224/228) and put down 400/367 through a 12-bolt and driveshaft. This is with a lot of tuning time and keep in mind the slightly bigger cam. What really pisses me off about it is these cams are supposed to make great torque to the detrement of high hp peaks, but it wasn't the case in my car. Mine seemed to just plain suck as both. All I hear from EVERYONE is "swap the heads, they suck". Had it been my project and not the previous owners, I never would have bought them. I'll be fixing the problem as soon as possible.
2) You're in the same boat as me with these damn Patriot heads. They just plain suck.
My advice if you're looking for numbers closer to 400/390, swap the cam and absolutely swap the heads. I'm sure all of these guys are right that you will pickup quite a bit by working out your tuning issues, etc, but I don't see much of a reason for making much more than you did on the last dyno you mentioned. You have a baby cam and crappy heads.
For comparison, my car has similar Patriot Heads and a slightly larger cam (224/228) and put down 400/367 through a 12-bolt and driveshaft. This is with a lot of tuning time and keep in mind the slightly bigger cam. What really pisses me off about it is these cams are supposed to make great torque to the detrement of high hp peaks, but it wasn't the case in my car. Mine seemed to just plain suck as both. All I hear from EVERYONE is "swap the heads, they suck". Had it been my project and not the previous owners, I never would have bought them. I'll be fixing the problem as soon as possible.
