Indy Intake Manifold power bands and availability.
03 thanks again for posting the numbers. Apples to apples, against Buschur's stock ported intake with a stock TB: v1 +49whp/+46ft/lbs. v2 +54whp/+43ft/lbs. corrected to the stock intake run in Feb. I believe these runs were done with less boost than the other manifolds run in his magazine test. v0 numbers this week. Thanks, Indy
Last edited by Indy Evo; Jul 14, 2008 at 06:28 PM.
It's difficult to determine what to do here. IX turbo on E-85 on a car that is built for road racing and autocross, so I'm more concerned with spool and mid-range than top-end. I also lose power dramatically above 5500rpm due to altitude, so I shift at 6300-6400. I was considering porting the stock IM/TB, but I haven't seen a graph of those specific mods vs stock nor the V0 vs stock or ported. Then, I have to decide which combo would mate with the Green in the same scenario...hmm.
Warr, I say go green and v0 and be done with it. It's most likely going to be the best combo for top end power and quick spool down low. I think that any of these manifolds on a maxed out stock IX turbo are going to die off after 6500, the turbo is just out of gas up there.
Altitude, temps, humidity..........all play a roll in hp/ET's. I personally do not feel that they play as big an effect on a turbo charged car as they do on a naturally aspirated car.
I've told this story before. I'll tell it, briefly, again.
Early 2000's we were at Bandimere racing, 5800 ft. The best my car had ever run was a 7.9X.
We got there and the car wouldn't start. We pulled the head, found that my dumb *** had put the pistons in backwards and all the intake valves hit, bending them. A local guy ran and got me a new head gasket. I had no ring compressor so we gently pushed one piston to the top at a time, moved the crank around and spun the pistons in the bore so they were positioned correctly. Put the car back together, still wouldn't start. Compression was under 90 psi in each cylinder. We hit it with some starting fluid and it fired. I then held the engine on the rev limiter on and off for fairly long periods to try to get the valves hot enough to slam them against the seats and straighten them out. We finally got it so it would atleast start on it's own.
The car ran either an 8.1 or 8.2 there with the engine in that shape. So at most .2off from it's absolute best ever.
IF the car is tuned for altitude and turbo charged I don't think altitude will hurt the ET by much, if any.
I've told this story before. I'll tell it, briefly, again.
Early 2000's we were at Bandimere racing, 5800 ft. The best my car had ever run was a 7.9X.
We got there and the car wouldn't start. We pulled the head, found that my dumb *** had put the pistons in backwards and all the intake valves hit, bending them. A local guy ran and got me a new head gasket. I had no ring compressor so we gently pushed one piston to the top at a time, moved the crank around and spun the pistons in the bore so they were positioned correctly. Put the car back together, still wouldn't start. Compression was under 90 psi in each cylinder. We hit it with some starting fluid and it fired. I then held the engine on the rev limiter on and off for fairly long periods to try to get the valves hot enough to slam them against the seats and straighten them out. We finally got it so it would atleast start on it's own.
The car ran either an 8.1 or 8.2 there with the engine in that shape. So at most .2off from it's absolute best ever.
IF the car is tuned for altitude and turbo charged I don't think altitude will hurt the ET by much, if any.
It has about half the effect on turbo'd cars as it does N/A, but it's still a large effect. The larger and more efficient the turbo, the less it seems to matter, but when you're already at the limits of efficiency at sea level, then you have no way to compensate at altitude. The standard CF for SAE up here is usually in the 1.25-1.30 range as calculated by the weather station. This seems to be just right for N/As, but we cut that in half for turbo'd cars when trying to estimate sea level numbers. I just use uncorrected, but it's all just numbers.
Fact is I lost 40whp peak and closer to 50whp at 7k rpm when moving from VA to CO. Even with a retune and trying to raise the boost, I got no closer except for a little bit before 5300rpm:
Green line is at sea level just before moving. All the other lines are at altitude right after moving. Each line is a different boost/tune level - I kept going up until it was maxed. You can see the highest curve, which is around 28psi MAP. It gives me peak torque closer to the sea level one at 26psi, but notice how it falls right back inline with every other pull at around 5500rpm.
Huge loss in spool, big loss in peak whp, and huge loss in top-end as you can see the curves diverging as RPMs increase.
Fact is I lost 40whp peak and closer to 50whp at 7k rpm when moving from VA to CO. Even with a retune and trying to raise the boost, I got no closer except for a little bit before 5300rpm:
Green line is at sea level just before moving. All the other lines are at altitude right after moving. Each line is a different boost/tune level - I kept going up until it was maxed. You can see the highest curve, which is around 28psi MAP. It gives me peak torque closer to the sea level one at 26psi, but notice how it falls right back inline with every other pull at around 5500rpm.
Huge loss in spool, big loss in peak whp, and huge loss in top-end as you can see the curves diverging as RPMs increase.
When it comes to correction factors, I try to avoid comparing sea level cars to altitude cars and I'll leave it at that with regards to altitude.
Correction factors are for comparing one run to another on the same car on the same dyno. Exactly what this thread is about.
Correction factors are for comparing one run to another on the same car on the same dyno. Exactly what this thread is about.
The first two v0's are on the way to Buschur's for testing. They should be delivered on Tuesday in time for a dyno and on track testing by Trent-o-matic. AWD will get a v0, and v2 custom w/ 3" Wilson TB next week, stand by for more dyno and on track testing next week. 9sec9, and OKIX will be running at tonight at Tulsa for the first shakedown runs since the new build. Good Luck guys, Indy
