My Blue Printed engine in my Scorpion can now rev over 9000 RPM with the right cams and carbs of course
I was reading this post for a while and checked my 308 carb drysump euro today, here is a picture of the inside of the airbox. Car is stock with no modification... You can even see the light coming from the scoop... There's no grill on mine. (1979) Image Unavailable, Please Login
Yep, that would be a Euro box....LOL! Welcome! The namplate on the snout is also a rare, early wonderful feature...!!!
Has anyone out there compared a factory airbox with the individual carb filters? I've tried them but did not quantify the difference (if any). I know the hot air is supposed to make a big difference, but have never seen any hard numbers. would also be interested in hearing anyone's experiences with using the individual filters, wire mesh or open trumpets. I will say from the time I ran individual filters, they are very loud!
Russ, just saw the engine .....looks fabulous! Looks like powder coated headers and coil overs for the suspension. Very impressive. I like the idea about individual filters for each carb inside the air box. My air box has two snorkels for what it's worth. I have to reread the thread. Ciao, George
Here's a data point: I previously was running the individual filters that I bought from Russ years ago (and yes they are loud). I had 55 idle jets with them and thought that I was running a little lean because I had the idle adjustment screws out about 5 to 6 complete turns to get my highest idle. I decided to put the original airbox back on with 60 idle jets. The adjustment screws were out about 3 to 4 complete turns for the highest idle. I thought this was good until I drove it. Apparantly this was way too rich. The plugs loaded up (I believe) and the car stalled several times. I had to rev it around 2000 to 3000 at a stop to prevent it from stalling. I have since gone back to the 55's and all seems good. When I did have the individual filters on, I did a test and the engine compartment temp was only about 10 degrees higher than ambient. Except, when at a stop the temps went higher because of no air flow. I'm still going to keep the individual filters in hopes of building an air box around them that would possibly use the engine lid as the top cover (that won't be for another 6 months soonest). I do think that it breaths better with the individual filters, but would like the cooler outside air, as well as the ram air effect.
Very interesting. It was shown a few years ago that there is negligible effect from the ram air, other than to just keep cooler outside air flowing in. Ten degrees is an amazingly low difference seems to me - I guess that was with the open duct blowing air on the carbs. If you can keep the temp difference that low, I'm pretty sure that those individual filters will outflow about anything - and keep the V of the engine open for airflow and carbs cooler. As Hank says, it is amazing how loud the induction can be on these cars. So Hank - how's that boy doing?
Hey Russ, Happy holidays to you and your family (as well as everyone else in Fchat land). Lucas is doing great thanks. He is a little over 3-1/4 years old. Still not potty trained yet though . Yeah, I think the way to go would be to build an air box around the individual filters...cut down on the induction noise, cooler air, and the negligible ram air effect. I hope to "install/test" some euro cams that I bought from Scott Mcgahee a couple years ago within the next few months. Any suggestions that you have on jetting would be greatly appreciated. I'm going to dyno before and after. Again, I got dibs on your motor if/when you decide to sell it .
Henry, if you design an air box would you make it with 2 snorkels to get a ram effect from both side? Based on the photos it appears that air is pulled from only one side. Merry Christmas and a Happy New year to Russ, Paul, and of course Henry. Ciao, George
Hi George, Unless the car is always operated in very cool climates, you are going to need the left hand scoop to provide cool air to the oil cooler. If you use both air ducts for cabs, you are really going to need to cool the oil. regards, chris
Thanks Chris. Theoretically, if you could pull air from both sides would you generate more hp. right? My oil cooler sits under the radiator, and I have a double snorkel air box. I'm thinking individual filters for each set of air horns inside the air box and leave out the stock oval air filter. Also other modifications are in line for the air intake, but probably not pertinent to a Ferrari thread. This thread has been most interesting for me in terms of reducing air restriction to and within the air box. Thank you everyone! Ciao, George
Hey George, Actually, I hadn't thought about scavenging air from the other side. Let's see...if the ram air is negligible from the one side, then a little more from the other side would be a little more than negligible . I'll take a look at the driver side snorkel and see how easy/hard it would be to tap into that duct. If it isn't too hard, then why not. Please keep this in mind though, I've been thinking about doing this for about 3 years now and have not got around to it yet...let's see Lucas is a little over 3 years old. Might be a correlation
Just based on what I have seen, it's not about pressure but about flow. If you keep the stock filter, I would bet that a duct from the other side would help. Making fresh air more available to the "far end" of the air filter would just have to help. With mine, I removed the stock air filter and substansially narrowed the stock airbox, so the airbox is really an open plenum with a cone filter at the entrance to the duct, so different situation depening rather on air velocity. Image Unavailable, Please Login
Hi Russ, I am posting the below paragraph in the M section, however in principal it can apply to any engine. As a side note, in my case both snorkels are on one end. I have read that the oiled [as in K&N] filters let too much dirt in[ don't know if that applies in your case]. I ran a K&N on the Z for years and switched back to stock, with no perceivable difference FWIW. While I have things apart, does anyone have any thoughts for, or against ceramic coating [aluminium color of course] the intake manifold on the outside to reduce the inside air flow temperature? Also, how about honing out the intake runners as well, to a slippery smooth surface for better air flow. I noticed that the two metal gaskets [above and below the carb spacers] have a slightly smaller I.D. than the other I.D.s thereby restricting air flow into the manifold. Matching everything up ought to give me at least a .2 hp increase. LOL. Ciao, George
One of the tenents of porting I have learned (and I am very basic) is that airflow hates to go from a smaller diameter to a larger one. Therfore, the air carriers should always stay the same or steadily get a bit smaller, say on a 5 degree taper. This way flow continues and picks up velocity driven by the air behind it. The venturi in the carb amplifies the vacuum signal, and is shaped to provide the least resistance possible. So when you look at opening up your manifold, it should match the area of the base opening of the carb (port-matching) and steadily decrease to the port area of the head. and just to be complete, make sure the ports match and there is no gasket sticking out - this actually happens A LOT. In the system I have, this same concept was applied to the air box. Starting with the area of the base of the K&N cone filter, it smoothly transitions to the same area, or a little bit smaller at the cross section of the airbox, delivering a velocity of air driven by the combined suction of the carb bellmouths. The combined area of the carb bellmouths is then just under the cross sectional area of the box, then each induction path is port matched and tapers to the valve. Anyway, be careful that you do not have the air go from a smaller area to a larger area in the runner, as that really kills flow. Another thing is air hoses and tubes with non-smooth walls, like the corrugated stock hose on the K-jet cars - that also really kills flow Image Unavailable, Please Login
Nice engine, mine is heading in that direction. Are those wire retainer clips holding the wires attached to the cam cover or just loose?
What do you guys think about having my idle screws out about 5-6 turns for best idle? Is that an issue or is that OK? I've heard others say they should be out about 3 turns.
