I'm assuming that the gas mileage isn't to good for that cam mod. Moving the cam back one tooth only brings the 2 closer to valve overlap. You might feel it pulling hard in early RPMs but power drop off is more significant before 5600RPM.
You may also experience detonation. BTDC isn't set right, just moving back one tooth I believe is around 7degress, that is more than the recomended 3 degress without proper ecu tuning.

 

You know so much but I see you have much to learn. I'm not changing when the Spark fires but when the Valves open and last time I checked Overlap makes Power. I haven't noticed anything drastic as far as the gas mileage goes and I've been putting a lot of miles on the car lately. I can pull up four 14 sec. quartermile timeslips that were done on this Mod and a couple of Bolt Ons. Hell before this I don't even remember seeing an All Motor KA breaking the 15 sec. barrier.

 

You missed my point... Spark timing is infact increasing your cylinder temprature. When you move the cam back one tooth you allowed for fuel and air to mix more LEAN (and infact since the valve has been RETARDED to open, not all the fuel is being used properlly in the atomization process, (you might also lose a sufficient amount of compression) your injection is set to go off at the proper time of lift for proper atomization), what you want is STOICH, if the mix becomes to lean by allowing it to compress longer, cylinder temprature increases. It could be dangerous for the engine. ( But then again I could be wrong)
I might try this mod myself to find out how safe it is, I'll read the knock signal off of the SAFC.
Too much overlap on NA is bad (horrible on fuel economy).

By any chance would you be putting this setup on the dyno soon????

 

id like to see power/safety of this mod as well, but if bigvinnie is correct, the leaning out of the motor could be contributing the the heightened performance that your feeling.

 

I think your'e over anaylizing this one. Anyone who has done the 4 tooth method knows that the Intake Cam is Advanced way more than the Stock profile, thats why it doesn't make any power untill after 5000 RPM. 3 Teeth puts it more in the KA sweet spot and with Cam Gears and Changing Base Timing I think we have a winner here. I always thought you had to pay to play meaning Gas Mileage is not one of my concerns, Power is. Plus I think the ECU can handle it because my Gas Mileage hasn't changed enough for me to notice it.

 

Tloof is a certified engineer and engine mechanic. I use to talk with him in the Z24i/Datsun 720club before I started over here in club 240 years ago.
Technically iof you want to properlly tune the 248 you can set it at 4 teeth as recomended and retard the timing with a timing sprocket 1.75degress which would set it to stock timing with the crank.

 

Vinnie as soon as you show me a Timeslip that is better than the 14.8, than all you are doing is talking out your *** because I drive my car everyday so how are you gonna tell me that I'm not making any power and you haven't even tried it for yourself. Stop talking in Theory and prove what you are saying.

 

I'm not talking out my ***. Tell that to the techs and engineers at nico. Not here to start whatever you think is beef, but the fact is that the intake vave is open during TDC, (it's all bad, and including part of the upward stroke)...

 

wel hey, im thinkin about swaping the 91 cams into my s14 too. but hey you said that you dont see all motor breaking 15s? wel i just happend to run a 15.30 on 1/4 with all bolt ons, full interior, old motor oil, and bad clutch. my reaction time was 0.6sec. im just saying i dont think it takes much to hit 15s with these ka's. but cant wait to see how the cams will perform. i'll post it when i do.

 

I hit a 15.3 also with a bad transmission, and my timing on the distributor was off. I was still rockin the stock cams...

 

My car ran 15's last year and I haven't had a chance to get to the Track this year but I bet I'm in the 14's now so we'll see. I'm not Beefin' with you Vin, I'm just trying to say for all the so called experts at Nico or anywhere else why haven't any of their cars got into the 14's yet. So the guys who want to talk about the same old Parts over and over again go ahead, but when someone thinks of something New or tries something out of the Box i'm interested. So why don't you get a good Transmission and by the end of the Summer lets see who really knows what they are talking about. Don't forget to get that Distributor Timing corrected.

 

It's all good man. I'm hittin the track shortly with a new ecu tune. Clocked my timing on a digi light about 19.50BTDC, (better responce on crappier fuel).
Still using the stock cams and hopefully a 14.8~15.00sec, and I might just have a freshly lubed trans ready to go.....

 

I bust your ***** alot Vin but you were probably the no. 1 reason I scrapped my KA-T plans and decided to stay N/A for the time being. Although Ivans new work is Motivating me in the other direction.

 

mmmmmmmm... for now i'm going to just do the 248/248 combo. when i see slips and hear more testimonials... maybe i'll mess with the 3 v 4 tooth method. gotta drive the 240 everyday untill i finish with school.

 

It wouldn't be to hard to check it out, and get a good dyno number for this. If you are running the dual exhaust cam either 3 or 4 tooth and go to the dyno you can do a few runs to get your baseline and then pop off the valve cover and move the cam, reassemble and go after it to check the numbers. It doesn't take long to adjust those cams. Wish I had the time/money to try some of this stuff.