GTPer Posted August 26, 2014 Report Share Posted August 26, 2014 I've been thinking for awhile now. What good does a cold air intake or fenderwell intake do to a supercharged car? The way I see it is by the time the air is pulled through the intake and gets into the supercharger the air heats up when it is compressed. On a N/A car I can see how a cold air intake helps because that cold air gets directly into the engine because it isn't heated up by a supercharger. So won't an open cone intake be just as good as a cold air intake on a supercharged 3.8? Or am I missing something? Quote Link to comment Share on other sites More sharing options...
Nas Escobar Posted August 26, 2014 Report Share Posted August 26, 2014 The fact that ambient engine temperature is about 210F is the major thing. Sure it heats up, but would you rather have 70F air heat up to 160ish or reuse that 210F air? Quote Link to comment Share on other sites More sharing options...
GTPer Posted August 26, 2014 Author Report Share Posted August 26, 2014 I'm not sure what you mean by 70F air heating up to 160ish. Quote Link to comment Share on other sites More sharing options...
l67ss Posted August 26, 2014 Report Share Posted August 26, 2014 Im of the school of thinking "true cold air" intakes arre a waste myself. Sure you get colder air but damn all the restrictions. Also most come out near the road or tire, which ive never seen a cold highway when cold air is needed most, and by the tire its much easier to pick up moisture. I saw a thread on grandprixforums awhile back where they did side by side comparo of several cais compared to an hai, on the dyno the hai won by several hp. Think of trying to breath through a long crazy straw in a walk in fridge compared to breathing normal on a normal summer day Quote Link to comment Share on other sites More sharing options...
rich_e777 Posted August 26, 2014 Report Share Posted August 26, 2014 I'm not sure what you mean by 70F air heating up to 160ish. Surely you do not think that the air being pulled into an engine will remain the same temp.? You will be fine with a High flow cleanable Spectre drop in filter. Quote Link to comment Share on other sites More sharing options...
Euro Posted August 26, 2014 Report Share Posted August 26, 2014 Don't bother with a FWI. Open cone is fine. IMO it's not going to benefit you THAT much between the 2. Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted August 26, 2014 Report Share Posted August 26, 2014 doing some quick calcs using a gen5 M90/3800 as a basis: sucking in 70*F air at its peak efficiency of 62%(~6PSI at 6000 blower RPM with the stock 3.9" pulley that is 3,333 engine RPM due to 1.8:1 overdrive), the temperature of the compressed air will be 150.5*F. the same calc using 120*F air(reasonable for underhood temps on a hot day), you end up at 208.1*F. higher pressures will produce even more ridiculous numbers. you tend to end up compromising between tubing complexity/restriction and colder draw points..... or you can just keep the factory stuff seeing how it draws air from behind the headlamp(cooler) with very little bending going on. if you need more air than that, start modifying air paths into the area. Quote Link to comment Share on other sites More sharing options...
Schurkey Posted August 26, 2014 Report Share Posted August 26, 2014 Have any of you put a vacuum gauge on the intake system to see how much of a restriction the factory system actually is? First Guess: Not enough to care about. Quote Link to comment Share on other sites More sharing options...
94 olds vert Posted August 26, 2014 Report Share Posted August 26, 2014 (edited) The stock air intake system is fine. It does its job better than an open cone and even most or all CAI systems on the market. Most people with 97-03 GTPs add a CAI to make the whine of the supercharger more noticed. Edited August 26, 2014 by 94 olds vert Quote Link to comment Share on other sites More sharing options...
GTPer Posted August 26, 2014 Author Report Share Posted August 26, 2014 Yeah that's what I want, to increase the whine. It isn't noticeable at all unless it's a cold day or at higher RPMs. On my 97 GTP though the stock system is not fine. It has two big bends on each side of the intake tubing and the PCM blocks about 3/4 of the intake opening. That's why a drop in filter would do no good. Quote Link to comment Share on other sites More sharing options...
94 olds vert Posted August 26, 2014 Report Share Posted August 26, 2014 97s and 98s had an inferior intake compared to the 99+. The newer intakes have no bends. I have a wizaired intake in my gtp and I love it. The whine is nice. On a cool summer night gives a great sound. Quote Link to comment Share on other sites More sharing options...
GTPer Posted August 26, 2014 Author Report Share Posted August 26, 2014 This is what the stock intake box looks like. A big bend to get through the filter, with the PCM right in front of the filter then into the tubing then a small bend going to the throttle body. Quote Link to comment Share on other sites More sharing options...
94 olds vert Posted August 26, 2014 Report Share Posted August 26, 2014 Moving the coolant bootle isnt a big deal and would be worth it. Quote Link to comment Share on other sites More sharing options...
GTPer Posted August 26, 2014 Author Report Share Posted August 26, 2014 I know I would get a closed iintake like that like from ZZP or Thrasher but then I also gotta buy a 99+ coolant bottle and move it. I wish I had a 99 or newer it would be so much simpler. Quote Link to comment Share on other sites More sharing options...
Heartbeat1991 Posted August 26, 2014 Report Share Posted August 26, 2014 Also of note, rubber intake tubes will shrink a certain amount under vacuum. A solid tube will not. As Robert Saar pointed out, a 60 degree difference in air temp will likely out weigh any curved restrictions. In either case, colder air is more dense, and packs more power. Quote Link to comment Share on other sites More sharing options...
l67ss Posted August 26, 2014 Report Share Posted August 26, 2014 Im of the school of thinking "true cold air" intakes arre a waste myself. Sure you get colder air but damn all the restrictions. Also most come out near the road or tire, which ive never seen a cold highway when cold air is needed most, and by the tire its much easier to pick up moisture. I saw a thread on grandprixforums awhile back where they did side by side comparo of several cais compared to an hai, on the dyno the hai won by several hp. Think of trying to breath through a long crazy straw in a walk in fridge compared to breathing normal on a normal summer day again Quote Link to comment Share on other sites More sharing options...
Heartbeat1991 Posted August 26, 2014 Report Share Posted August 26, 2014 Again. You can't really compare a human breathing through a straw in a refrigerator to an engine. Quote Link to comment Share on other sites More sharing options...
GTPer Posted August 26, 2014 Author Report Share Posted August 26, 2014 So you guys are saying a short straight open cone is better than a long bent fwi even if it draws hotter air? Quote Link to comment Share on other sites More sharing options...
GTPer Posted August 26, 2014 Author Report Share Posted August 26, 2014 So it looks like there's some division as to which is better. Quote Link to comment Share on other sites More sharing options...
Heartbeat1991 Posted August 27, 2014 Report Share Posted August 27, 2014 So you guys are saying a short straight open cone is better than a long bent fwi even if it draws hotter air? I don't think so. But I think that's that L67SS is saying. The air will be warmed up as it passes through the engine bay, and more so in the supercharger. The colder the air is to start with, the colder it will be when it gets through the intake. The warmer it starts, the warmer it will be when it gets through the intake. colder = better. Hence the purpose of an intercooler. Quote Link to comment Share on other sites More sharing options...
94 olds vert Posted August 27, 2014 Report Share Posted August 27, 2014 [video=youtube;-jbfz8I9sBE] This is what my car sounds like. I love that whine. You will not gain any power with a CAI heck you may actually lose a HP or two, but if you want a whine then yes get a CAI. A 1997 and a 1999 GTP have the same HP and TQ figures the different air intake had no affect. Car with stock air filter the whine is hardly noticeable[video=youtube;R2ZdQBDG83I] . Quote Link to comment Share on other sites More sharing options...
GTPer Posted August 27, 2014 Author Report Share Posted August 27, 2014 An air intake doesn't really compare to an intercooler though. A little cooler air from an intake is insignificant to the temperature difference an intercooler makes. But I see what your saying about the warmer the air starts the warmer the air gets and vice versa. I guess what I wanna know then is, is the difference in IAT from an open cone and a fwi really that big to be significant compared to how hot the supercharger gets the air anyway? Quote Link to comment Share on other sites More sharing options...
94 olds vert Posted August 27, 2014 Report Share Posted August 27, 2014 Maybe this will help... [video=youtube;gCi2yo4UqPI] Quote Link to comment Share on other sites More sharing options...
l67ss Posted August 27, 2014 Report Share Posted August 27, 2014 Again. You can't really compare a human breathing through a straw in a refrigerator to an engine. actually it is a good comparison as the same air you breath is the same air running thru the car and will react similar Quote Link to comment Share on other sites More sharing options...
Heartbeat1991 Posted August 27, 2014 Report Share Posted August 27, 2014 actually it is a good comparison as the same air you breath is the same air running thru the car and will react similar Not exactly. I don't run better on colder air. And my lung capacity is far less than an engine. The length of the intake tube is irrelevant to an engine. It inhales and exhales at the same time. The amount of vacuum created doesn't diminish with length. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.