BIGBOS

So when I get this Griffin FMIC, should I be expecting to lose boost along w/power?

Guess I better order that smaller pulley for sure

Pro Stock John

iTrader: (34)

Silver Bullet is running a 3.4 pulley so you might be okay to start.

You can put timing back into the engine and that will help bigtime. If you can put like 4-6 degrees more timing into it that's huge.

BIGBOS

Im at 22 degrees of timing for HP and 19 fot TQ PEAK

This is with the 100 octane I run straight and the 160 air temps.....

And the power I make is 462rwhp and 522rwtq, I'll still pulley it down to a 3.2" and try and max out the D-1SC....

I'm convinced I need a cam change though

S_J_H

BIGBOS, I don't think you should lose boost. The stock ati intercooler system is pretty convoluted with a zillion bends, radiator hose for piping and 2 small intercoolers. I think going with the Front mount and building nice hard piping should actually increase your boost and at the same time drop IAT. I'm not sure how much more timing you can add as 22 degrees is a pretty good amount already.

I fabbed up the new direct outlet piping yesterday. It is 2.75" out of the blower and then the first bend is 3" and the second big bend after the maf is 3.5". The blower should sense this as a straight piece of pipe and be very free flowing.Even more so then my last non intercooled piping that was only 2.5" constant area and IMO to small.
I also after each piece was welded, internally ported each pipe junction to make it very smooth and eliminate any lips inside from the butt welding process. Something I did not do with my last effort. Plus my last effort was still in draw through maf mode witch kept the blower very hot from recirculating the mondo bypass back into the blower inlet.
I am hoping to see some darn good boost and flow numbers. This is it guys, this is about as free flowing a G-trim setup on a ls1 your ever going to see! big 4" inlet and big direct output to T.B.
here's some pics of it. I still need to prime and paint. It will be interesting to see how high IAT's go and boost results.

XIII

This topic has me very intrigued. If I understand correctly you lost boost after adding the intercooler and based on some logs you are running slower. I have some questions based on those comments. There are just 2 possiblilities on why there is a substanial loss of PSI right? Cooler IATs and the intercooler restricting airflow. Obviously cooler IATs are going to lower the PSI due to the air contracting when cooled. That wouldn't cause you to lose power though right? The same amount of air is flowing into the motor (assuming no additional intake restriction) allowing you to make the same power. So wouldn't that mean that the power loss is most likely due to the intercooler restricting airflow? So in this case wouldn't a less restrictive intercooler provide better results since you don't have the option of using a band-aid fix by pushing more CFM with the blower?

S_J_H

Any intercooler of conventional design is going to be a restriction of some sort. The more pipe and bends the more loss due to friction .There is no way around this. Some will be better than others. When they rate an intercoolers pressure drop they certainly do not flow test it on a blower spinning 5000rpm over it's max impeller speed rating like I am doing.
IAT did not drop near enough to account for a 2-3 psi drop in boost down low. So it had to be the restriction or flow dynamics or Voodoo.

The interesting finding was how the intercooler really flattened out and dropped off boost response down low but it was not as bad up high. The restriction is going to be worse at high flow not better! So somehow it effected the flow and pressure buildup of the blower at lower impeller speeds. Why? I have no friggin idea

Increasing the blower speed is not really a band aid. That's just the way it is.Turbos do it automatically provided it is a large enough turbo. You really never know what the impeller speed with a turbo is.

But with a blower your controlling impeller speed by belts and gears. So pressure drop and restrictions are much easier to measure. Putting a probe before and after the intercooler is not a true way to measure blower output change because the system works closed loop.

I picked up a full LB of boost fabbing the 4" inlet vs the stock Vortech 3.5". Porting the blower was worth another .5psi. Redoing the outlet ducting was worth another 1lb. I have seen how restrictions effect this unit. I did a lot of work to get the flow and boost from this unit. So naturally I don't want to go backwards in output flow.
Like I said before, I still got a solid 11psi with the intercooler. Take a good look around and see how many ATI guys let alone G-trim guys get more than 11psi. So I do not believe it is really that restrictive. Just enough to upset flow out of this over spun unit.

I just want max power out of this little G-trim Unit. Might be a ego thing or I'm just plain obsessed about getting all my power out of this Blower. And that means dumping the intercooler.
I'll probably build another alky system. Plus I'll just program the pcm to pull timing with higher IAT's as a safe guard.
Steve

S_J_H

some good did come from all of this though. I learned just how benefical it was to place the maf on pressure side and bypass to atomsphere. That alone without an intercooler drops crusing IAT by up to 40 degrees!

So a run starts out with much cooler initial boost. Also the blower runs much much cooler since it is not recycling hot air back into the inlet, and re compressing it.
I learned the hard way putting a bigger bypass on a recyled system only makes for even hotter temps!
I'll have some logs by the weekend. Maf is in same location so maf flow comparison will be fairly valid this time.
Steve

BigPlanTransAm

thats what i was thinking at first but he said its a book about intercooing specifically

S_J_H

well tested out the new direct piping today. Saw 10psi and then it blew out of the coupler. I need better clamps.
It's about 85' out today. Cruise IAT was 108' and then by only 90mph it hit 190'
I'm not sure at what point the pipe blew off and how much more boost was in it. It doesn't really matter.
190' IAT is hotter than I expected to see at only 10psi for such a short burst. I'm sure had the pipe stayed on and I ran it out to about 120mph+, IAT would have been well over 200'.
Looks like my budget intercooler was removing a lot more heat than I thought.
hmmm what to do.....

Shinobi'sZ

Go back to your IC and use it with the Water/Alky injection, it is cool that you gave it a shot..but not as cool as having an IC..literally.

I was having problems all along believing that not having an intercooler would be better than having one. I have never seen IATs that high with both twin IC and a Single IC setups. But than again you are going to have higher IATs withot the IC. Unless I am mistaken you were depending on the Water/Alky injection to prevent pre-detonation not lower IATs. Did it work??? Did you get KR?

Yes I was talking about the book "Maximum Boost" by Corky...in fact he emailed me not long ago about intercoolers. It is well documented in other Turbo and Supercharger design and testing literature.

S_J_H

This was the first time I ever ran the motor with no intercooler or alky with the 2.5" pulley.. 190' is the hottest IAT I have EVER seen with my combo in 3 years.
With alky and no intercooler on a cool day, IAT hit 170'. So the alky did not do that much for charge cooling which is why I built the intercooler. Charge temps actually measure much lower with a water/alky mix. But I suspect that is because the water is just wetting the sensor, as the charge temp is under the waters flash point.

The intercooler kept IAT to about 135' with 85 ambient temps.

It's safe to say the intercooler I built is worth about 70 degrees charge temp reduction with room temp water.
I'm still thinking about all of this.

Got Me SOM

iTrader: (2)

Running no intercooler will make you lose power.

direct quote from vortech:
About Vortech's Aftercooler:
The most effective means of reducing forced induction air intake temperatures is by using an air to water aftercooler. Air to water aftercoolers are currently being used by OEMs like Ford and Jaguar for supercharging systems. This superior air cooling technology is proven to reduce air intake temperatures by as much as 200ºF with minimal pressure drop. Air to water aftercoolers provide cooler, denser air charges allowing more timing, more boost, reduced chances of engine damage due to detonation and excellent drivability without the surge problems that are associated with air to air intercooler systems. The Maxflow Power Cooler utilizes a closed-loop water circulation system with a front mounted heat exchanger that allows for effective street operation with minimal boost loss. Gains of 25 to 100 additional horsepower are possible depending on the application, engine, and boost level. This system also allows the use of ice water for drag racing providing even greater performance. Installation is easy, stock ground clearance is maintained, and the optimal placement does not restrict engine radiator airflow.

Each system features an exclusive double pass, low restriction, air to water core, Setrab heat exchanger, heavy duty water pump, molded plastic polymer water tank designed to hold water or water and ice, and all necessary mounting brackets, hoses, and supporting hardware. Battery relocation is required on most applications. Complete bolt-on kits are available separately or as part of a complete Vortech supercharging system at a greatly reduced price. They are 50-state emission legal per CARB EO #D-213-15, OBD-II computer compatible and backed by a 90 day limited warranty.
This system features a fully integrated air to water aftercooler approach to charge cooling. Vortech chose the air to water system primarily because it closely maintains the boost level found at the compressor.
Vortech's Maxflow Power Cooler is the aftermarket's first street/strip, air-to-water charge cooler system. It utilizes a closed-loop water circulation system with a front mounted head exchanger that allows for effective street operation. Power gains up to 100 horsepower are possible depending on the application, engine, and boost level. This system provides cooler, denser air charges (discharge temperature decrease is approximately 100 F @ 10 PSIG), allowing more timing with less fuel required. (Greater air discharge temperature reductions are possible with higher boost levels and/or the use of ice chilled water in the reservoir).

Each system features our exclusive dual pass, high-flow, air-to-water-to-air cooler unit. The front mounted heat exchanger (cooler radiator) uses a low-restriction plate/fin design and is manufactured from high-grade aluminum. The water reservoir is roto-molded of high-strength plastic polymers for durability. It features an easy fill, wide mouth design for the use of water, ice or a combination of both. Also included is a heavy-duty water pump, mounting brackets, hoses and hardware.

Effectiveness is a term often seen, but also often misused. Strictly speaking, effectiveness refers to the steady state thermal performance of a heat exchanger, and is highly influenced by the flowrates on both the hot and cold side. Numerically, it is stated as a percentage and refers to how close the discharging hot air temperature is to the incoming cooling (fluid) temperature. Thus, it can only be evaluated under fully stabilized, steady-state conditions where the hot and cold side flowrates are carefully controlled and monitored. Vortech tests their charge coolers exactly in this manner to determine legitimate effectiveness performance. As such, typical effectiveness values of 70-85% + are routinely measured. Let us explain.

Having liquid on the cold side of the exchanger results in several very important advantages. First, water is over 9 times more conductive than air, so, the overall heat transfer coefficient is dramatically improved - many times per unit fin area over air-to-air. This affords a much more compact heat exchanger design. Secondly, the pressure loss on the air passage side is greatly reduced by the reduction in heat exchanger size and by the "open" fin area design. Compactness allows the cooler to be placed directly "in the run" from the supercharger to engine - little to no increase in ducting length occurs so ducting losses are absolutely minimized meaning charge density is maximized. Having a reservoir of cool liquid on-hand takes advantage of available thermal mass or storage of the coolant itself, i.e., the vast majority of boost/power demands are typically of short duration, resulting in very little overall temperature rise of the coolant itself. As the coolant is continuously circulated, cooled and stored "at the ready" at close to ambient temperatures, the charge cooler is always afforded Maximum Cooling AdvantageTM.

Better charge cooling - Aftercooler can achieve over 80% effectiveness.
Compact - Aftercooler is positioned "in-the-run". Short and direct ducting absolutely minimizes frictional losses (boost loss).
Supercharger boost and parasitic drive power does not have to be increased to overcome boost loss; supercharger will be making less heat in the first place and consume less power doing it.
You get more horsepower per supercharger PSI of boost.
Consistently cools the liquid system, even when not in boost, for charge cooing on-demand.
Ice water provision for competition.

S_J_H

Using a 20GPH alky nozzle would probably get me to 150' charge temps with no boost loss from restrictions. All that alky would make for great detonation prevention and no doubt is going to make more power than intercooled on gas only. BUT that's a lot of alky to rely upon!


According to Stealths density ratio calulcator- http://www.stealth316.com/2-turbotemp.htm

with the intercooler, even with a 3psi loss the overall density ratio is still a bit higher using only 60% IC efficiency -
I'll run the math myself just to make sure this is right. I need to figure out how much boost loss is from temp reduction alone before I make any more decisions.

S_J_H

Well I did all the math and I should have done it before I jumped to conclusions my intercooler was a restriction!
I guess I just did not understand the GAS LAW very well.
Doing the math equation for a Cooling of the air from 13psi/170' IAT to 118' IAT results in a pressure or boost drop of 2.3 psi from temp reduction alone. Just about exactly what I saw with the intercooler vs no intercooler + alky spray.
The intercooler is not a restriction and the boost loss I see is to be expected from the charge cooling effect alone. The intercooler probably only has a .5psi pressure drop.
The equation is P1/T1= P2/T2 using absolute pressure and temperature numbers.
For instance cooling 10psi boost at 190'F down to 135'F results in pressure dropping to 8psi ,which is shown as the equation- 24.7/650 = 22.7/595 .
Density ratio the same for either case also at 1.42
A 100 degree rise in air temp from 70' ambient results in ~2.75 psi increase.

The slightly slower logged runs may be a result of different a/f ratios and the effect of the old alcohol injection system.
So my boost loss is fully explained and the intercooler is not a restriction! Case closed.
Intercooler is going back in.
Steve

Got Me SOM

iTrader: (2)

yayyyyyyyy

slow

iTrader: (7)

I figured that you would go back to intercooled.

Ryan