do you have to run an intercooler when turbo or superchring?

[nvawgn]

if you have a choice is it always a positive to run an intercooler when possible?

[camcojb]

if you have a choice is it always a positive to run an intercooler when possible?

Always better to run with one in most all cases. No, you do not have to run one. I substituted water injection on mine and made very good power without an intercooler on pump gas.

Jody

[nvawgn]

thanks camcojb, does detonation have alot to do with it as well?

[camcojb]

thanks camcojb, does detonation have alot to do with it as well?

everything to do with it. Compressing the air heats it up, and the higher the temps the less timing and boost you can run to prevent detonation. So you can run a blown engine with no intercooler but you have to run less boost and less timing, which means less power. Anything you can do to cool the intake air or absorb the extra heat (water injection) will allow you to make more power safely.

Jody

[64duece]

As Jody pointed out....cooler charge means more power per/lb of boost.

A few years ago we tested intake air temps on a well built 355" SBC running 18lbs of boost. We started our testing w/ 240* intake air temps and made 720hp. We made controlled pulls on the dyno and lowered the intake air temp to a respectable 140*. Our next pull was really lean indicating there was more air density. Once we added the fuel, we noted 807hp.

With our new intake air temps, the engine now responded to added timing. Our first 2* netted 20hp across the board. Our next 2* netted an additional 20hp across the board totaling 847hp. That's a 20% increase in power! We stopped there as the combination was out of fuel pump and injector.

[Blown353]

With our new intake air temps, the engine now responded to added timing. Our first 2* netted 20hp across the board. Our next 2* netted an additional 20hp across the board totaling 847hp. That's a 20% increase in power!

I think you just motivated me to go throw more timing at my car now that I have the intercooler installed... I've dropped my IAT's by over 80F with the addition of the intercooler so it should be able to tolerate a bit more timing. I like the idea of another 40 or so HP through bumping the timing, but I am worried about pushing my luck too far and having some detonation. :willy:

I did pick up another 6% injector DC after installing the intercooler and there is a noticeable seat of the pants difference in power; the 6% IDC gain with my 75pph injectors is approximately another 36pph of fuel.

Dennis, what kind of timing numbers were you running on that 355, and could you share the details of that combo? Just wondering.

[64duece]

We stopped at 28* total. Although, that combination had some left in it. The springs were done and that specific intake wasn't the best choice for that hp level. I'd say it was good for 900hp with some new parts and tuning. It wasn't worth chasing a new fuel system, springs and intake. We switched to a turbo setup just a few weeks later.

The basics were 355" SBC w/ Dart Pro 1's (ported to approx 225cc), 248/254 solid roller, Holley EFI intake, D1 Procharger running 18lbs thru an air to air. We had maxxed out an "early" A1000 with approx 504lbs/hr running 13.8V and 70psi fuel pressure.
http://img.photobucket.com/albums/v231/64duece/stuff/dyno.jpg

[californiacuda]

Do you have the numbers after switching to the turbo system, you should pick up another 100 if you make the same boost. The supercharger parasitic loss is substantial(as you probably already know).

[64duece]

No specific comparison was made due to the difference in direction after we went with the 90mm and then 98mm turbo.

We swapped the 355" (4.030x3.48) short for a 374" short (4.125 x 3.5) due to the need for additional parts strength. We also switched to a water to air core aswell.

I will note: We used the same heads. Upgraded fuel system, intake and just abit more camshaft. With the intercooler air temps now in the 110* range, we now were making 1000hp using just 14lbs of boost. We followed that with higher boost levels, ultimatly reaching 28lbs making 1660hp with a tradional 23* head.

I've tested several superchargers back to back in efforts to see the parasitic losses. I can say, running a much larger than needed blower will "cost" you some power. We saw differences of nearly 100hp from using a unit that was "properly sized" and capable of producing required boost pressure vs one being "turned down" to the same pressure level. Also, the average power from the turbo was superior to any of the centrifiguals we tested.

[Blown353]

Thanks for the info Dennis. The bit about using a blower larger than needed and the additional power consumption is good to know, but makes sense being that you are probably working in an inefficient area of the compressor map when you use a blower that's too large for the job.

I hear you on maxing out a fuel pump, I'm eating about 510 lb/hr right now going by the injector duty cycle numbers. I had to add a Boost-A-Pump to keep up as I was right at the edge of maxing my SX pump out.

Non-intercooled with the EFI my setup would only tolerate about 22 degrees max timing. It used to tolerate 27 degrees with the carburetor but after switching to the tunnel-ram style EFI manifold I had to take a lot of timing out of it. I haven't tried putting any more timing to it with the intercooler but that's on the agenda for this week. The only thing I don't like is I have no way of noticing detonation except for checking the plugs-- the engine & supercharger are just too loud to hear anything except severe detonation over, and if I can hear that it's too late. Any suggestions? It's easier to pick up light detonation on a dyno as you can see the torque curve "bouncing around" but tuning for max power in the car makes me rather nervous as I have no reliable way to detect light detonation in real time, only an after-pass plug check.

[64duece]

No problem.

The timing #'s sound right. We were at 24* prior to adding an intercooler. I have a firend w/ a 406 SBC running upper 20's on pump gas with his blowthrough system.

You hit the nail on the head as for timing/detonation. My best advice is to stay conservative. :D Have a couple sets of NGK's on hand (we used 9's hot-air and 8's with cooler temps) and you should be able to read the ground strap. Pull all 8, keep a real close eye on the porcelean and sneak up on it. Tuning via mph is still a good process if you know your car and are willing to weather correct.

[Blown353]

You hit the nail on the head as for timing/detonation. My best advice is to stay conservative. :D Have a couple sets of NGK's on hand (we used 9's hot-air and 8's with cooler temps) and you should be able to read the ground strap. Pull all 8, keep a real close eye on the porcelean and sneak up on it. Tuning via mph is still a good process if you know your car and are willing to weather correct.

Thanks again Dennis.

Wow, those are cold plugs. I think I'm running BKR7ES plugs at the moment; I'm trying to balance street driving vs "beat on it" driving and the 7's seem to be OK; if I cruise the car lightly they look a little loaded up (even though I have the engine running quite lean at light loads) and if I beat on it then shut it down they look a little on the hot side but not scorching hot. Think I should go a little colder? I am running water injection so that is probably helping my plug choice quite a bit.

Still wishing an ion-sensing knock detection setup was cheaper than $20K or so. :lol:

[64duece]

Most of our stuff is pure race, not much idle cruize time :D I've run the 7's in the mid boost levels (10-14) and did have them in at 18lbs without "noting" problems but, I wanted to work out the timing without having a glow plug being a cause of problem. I played it safe and went to the 9's, they we're a little cold for sure. The 8's were fine, I was playing it safe.

I'll probably run 7's in my twin turbo 565 street beater. defiantly want to keep the plugs clean in there. It'll never see more than 12 to 14lbs and has water to air w/ heat exchanger.

[Diesel77]

To answer the question, no you dont need an IC to drive the car around and will make decent HP most of the time.

[boosted6]

As Jody pointed out....cooler charge means more power per/lb of boost.

A few years ago we tested intake air temps on a well built 355" SBC running 18lbs of boost. We started our testing w/ 240* intake air temps and made 720hp. We made controlled pulls on the dyno and lowered the intake air temp to a respectable 140*. Our next pull was really lean indicating there was more air density. Once we added the fuel, we noted 807hp.

With our new intake air temps, the engine now responded to added timing. Our first 2* netted 20hp across the board. Our next 2* netted an additional 20hp across the board totaling 847hp. That's a 20% increase in power! We stopped there as the combination was out of fuel pump and injector. In your last sentance, That would not have happened if you were using Methanol Injection! 1). Methanol Injection would pick up where your fuel system falls short seeing it's a fuel and another injector! with this said that also means it lowers your injector duty cycle quite a bit and you don't have to wory about intercooler heat soak.. Plus you loose the weight of the intercooler and don't spend a fortune on race gas...
ALOT of possitives to Methanol Injection.. :D

[camcojb]

In your last sentance, That would not have happened if you were using Methanol Injection! 1). Methanol Injection would pick up where your fuel system falls short seeing it's a fuel and another injector! with this said that also means it lowers your injector duty cycle quite a bit and you don't have to wory about intercooler heat soak.. Plus you loose the weight of the intercooler and don't spend a fortune on race gas...
ALOT of possitives to Methanol Injection.. :D


and some negatives. For example, if you're using the methanol as additional fueling as you state, and there's a failure in the system or you run out of alky then you have a good chance of damaging your engine. Many people do not tune for it for that very reason, although then you are losing most of the benefits of running alcohol injection (the ability to run more boost and timing on pump gas). Although I run water and/or alky injection on all my forced induction builds, running an intercooler is never a bad idea. There are cases where an intercooler is very hard to package, and the alky is a great way to go Actually, for heat absorption straight water is even better, but you lose the additional fueling and the slight octane boost of using alky.

My opinion, run both if possible.

Jody

[boosted6]

, and some negatives. For example, if you're using the methanol as additional fueling as you stated there's a failure in the system or you run out of alky then you have a good chance of damaging your engine. Many people do not tune for it for that very reason, although then you are losing most of the benefits of running alcohol injection (the ability to run more boost and timing on pump gas). Although I run water and/or alky injection on all my forced induction builds, running an intercooler is never a bad idea. There are cases where an intercooler is very hard to package, and the alky is a great way to go Actually, for heat absorption straight water is even better, but you lose the additional fueling and the slight octane boost of using alky.

My opinion, run both if possible.

Jody To reply to the bold print above. I like to try and eliminate Negatives!! Thats why it's nice to have fail safe's built into your system! I have several on mine. I have a LOW LEVEL sensor so you won't run out of Methanol (it's not that hard to check the tank before you drive it!)..
The low level issue. If you have an injection system installed, it must have a functioning low level warning device. If left to chance, at some point you will guess wrong! Whether it’s a light behind the dash, on top of the dash, a factory “Low Warning” etc., the location must be clearly visible.

The only exception to this rule is on professional race applications that require foam added to the fuel cell to prevent excessive sloshing. In these applications it is common for fuel, water, oil, and other liquids be inspected after every run.

Ok, we’re sure system has liquid. Now another “what if”.

Second:
System test. A “fail safe” injection kit MUST have test button readily available for diagnostics. our PAC controllers feature a low-pressure test of the system. It’s important to note that this is NOT a full pressure test that could potentially hydro-lock an engine.

Ok, we tried the test button and the air/fuel changed. Now what?

Third:
Diagnostics. A Progressive System: This feature allows the system to begin spraying early with very low pressure and substantially before detonation assistance is needed. Once spraying begins an LED light is illuminated, indicating system activation. As the signal (MAP/MAF/Boost) to the controller increases so does the drive to the pump. Once the system pressurizes, the LED color will change from red to green. This indicates the system now has developed pressure and that hoses, connections, and pump are in proper working order. The “rate of change” from red to green give a predictability of the system. Any noticeable changes to this “transitional time” will be an indication of a system issue.

Examples:
The filter clogs…the system will transition from red to green instantly.
Nozzle clogs. (oops, can’t happen…we have a filter.) Someone pours a bag of sand into the tank…system lights up red, can’t make pressure, no green condition.
Bottom line, a well-designed, basic setup provides a simple, easy-to-diagnose system that is RELIABLE.

Scot w.

[camcojb]

To reply to the bold print above. I like to try and eliminate Negatives!! Thats why it's nice to have fail safe's built into your system! I have several on mine. I have a LOW LEVEL sensor so you won't run out of Methanol (it's not that hard to check the tank before you drive it!)..
The low level issue. If you have an injection system installed, it must have a functioning low level warning device. If left to chance, at some point you will guess wrong! Whether it’s a light behind the dash, on top of the dash, a factory “Low Warning” etc., the location must be clearly visible.

The only exception to this rule is on professional race applications that require foam added to the fuel cell to prevent excessive sloshing. In these applications it is common for fuel, water, oil, and other liquids be inspected after every run.

Ok, we’re sure system has liquid. Now another “what if”.

Second:
System test. A “fail safe” injection kit MUST have test button readily available for diagnostics. our PAC controllers feature a low-pressure test of the system. It’s important to note that this is NOT a full pressure test that could potentially hydro-lock an engine.

Ok, we tried the test button and the air/fuel changed. Now what?

Third:
Diagnostics. A Progressive System: This feature allows the system to begin spraying early with very low pressure and substantially before detonation assistance is needed. Once spraying begins an LED light is illuminated, indicating system activation. As the signal (MAP/MAF/Boost) to the controller increases so does the drive to the pump. Once the system pressurizes, the LED color will change from red to green. This indicates the system now has developed pressure and that hoses, connections, and pump are in proper working order. The “rate of change” from red to green give a predictability of the system. Any noticeable changes to this “transitional time” will be an indication of a system issue.

Examples:
The filter clogs…the system will transition from red to green instantly.
Nozzle clogs. (oops, can’t happen…we have a filter.) Someone pours a bag of sand into the tank…system lights up red, can’t make pressure, no green condition.
Bottom line, a well-designed, basic setup provides a simple, easy-to-diagnose system that is RELIABLE.

Scot w.


Scot,

you obviously have a nice system, but there can still be failures, and a guy running through the gears at wot may not see the light changing, etc. Don't get the red to green instantly deal if the filter is plugged, seems like a red light is a better indicator of trouble. Now I have to watch how fast the led changes............I do know it's tough to watch lights/gauges when going wot with a 1000 hp street car. Unless your system would automatically cut boost and change the timing if there was a failure then you're still depending on the guy noticing the leds. I am not knocking it, as I said I use one on every build including my current twin turbo. Haven't tried yours, but have used 4-5 different ones and other than features they all seem to work well.

Also, you really should consider becoming a site sponsor. :yes:

Jody

[boosted6]

Scot,

you obviously have a nice system, but there can still be failures, and a guy running through the gears at wot may not see the light changing, etc. Don't get the red to green instantly deal if the filter is plugged, seems like a red light is a better indicator of trouble. Now I have to watch how fast the led changes............I do know it's tough to watch lights/gauges when going wot with a 1000 hp street car. Unless your system would automatically cut boost and change the timing if there was a failure then you're still depending on the guy noticing the leds. I am not knocking it, as I said I use one on every build including my current twin turbo. Haven't tried yours, but have used 4-5 different ones and other than features they all seem to work well.

Also, you really should consider becoming a site sponsor. :yes:

Jody The LED's are placed right by your boost gauge or the gauge you would look at the most.. but Your right, there can still be failures on anything but the more fail safe's taken, the better. I will become a site supporter and pay for advertising when the funds are better. right now i'm recovering from a ankle fusion and recovery is 3-4mo. short term disability only goes so far.
Scot w.