chiplee Posted April 6, 2008 Author Report Share Posted April 6, 2008 I just wanted to agree on a simple truth as a starting point for discussion. There is no debate needed regarding the simple truth I'm talking about, and that is that ALL THINGS BEING EQUAL, ie, weight, traction, blah blah, a given engine, in a given car will go faster in the quarter mile if it is tuned for higher HP. again, individual examples of exceptions to this rule do nothing really to strengthen either side's point. the thing I really want to get at is a sort of sweet spot for our cars, where we can expect a reliable 11-12sec street car. I'll experiment with that myself this summer though. oh and here's a pretty good article I've posted here before on the hp/tq discussion. http://www.vettenet.org/torquehp.html Link to comment Share on other sites More sharing options...
Chad Posted April 7, 2008 Report Share Posted April 7, 2008 It's a good read, worth while to anyone and everyone. I read that document about 5 or 6 years ago, I almost quoted the L98/LT-1 comparison, but I couldn't remember the source of the info. This document is where I came to understand the math behind torque vs. HP, and why it matters so much. Given the water wheel scenerio, it's a great example of how useless torque is if you can't make it at a high frequency (RPM). Link to comment Share on other sites More sharing options...
TainterRacing Posted April 7, 2008 Report Share Posted April 7, 2008 The reason it seems to have a lot to do with racing is if you have a high tq motor your Hp comes on sooner making a broad Power band. Link to comment Share on other sites More sharing options...
Tim_C. Posted April 7, 2008 Report Share Posted April 7, 2008 A problem we have hit on too, is we are too heavy to make torque the target unless you lose that weight, or substantially beef the drivetrain. That's another reason I welded up the mounts on mine. I want all the power possible to get to the pavement with little hop or slop that adds awkward stress on the axles, torque tube, trans, drive shaft, etc.... Our cars were made way too sloppy in the mounts. All you need is the rubber on the outer mounts of the trans. That's enough to absorb a lot of vibration, but keep everything from moving too far for its own good so to speak. Link to comment Share on other sites More sharing options...
Shelby Posted April 9, 2008 Report Share Posted April 9, 2008 for drag raceing the main target point your after is to keep the engine in the fastest posible rpm increaseing range while under full load , you rate of excelleration is what your looking for,, how fast the vehicle gains speed in what ever gear .. for drag raceing you need both tourqe and hp,, one to get the vehicle moveing in the least amount of time posible to do this you need tires that do not slip and with out unlimit'd cids you must turn to tourqe and lots of it in lower rpm but once you have the vehicle moveing you have to focus on the rate the engine is able to increase the vehicles rate of excelleration , this you do by shifting gears to keep the engine with in a set rpm range,, in order to do this you run past the optimum point and start back into it slightly below where you want to be a point was made about some cars runing slower with a lower diff gear,,the reason for that is simple the engine ran thru it's usefull power range to fast and was not able to put the entire power to the work of increaseing the vehicles speed, with the higher gearing it is able to stay in it's optimum range of rpm increasement or peak excelleration point honda's if you put the same gear in them as we use they'd all be 16 sec or slower cars , in reverse if you use'd the same 4.6? gears you to would be 17 to 20 sec cars ,, why cause your completely out of your usefull working range , you'd be max'd out arround 1/2 way thru the 1/4 and no more gears to shift to the point with our car is you have to drop some lower rpm tourqe or all you'l do is spin tires and make up the differance in the upper rpms gain rate of excelleration every thing is a middle ground you can't have it all , if you want to keep your car what it is and not a 2k lbs piece of tin thats fun at the strip but don't look at it driveing arround town , those pro drag cars are nothing prety nothing fancy to drive arround and show off in but your full body'd car with all triming and still able to strip the rubber off the tires at will can be a blast to drive maybe a better gauge for judgeing how your cars runing would be a G-force meter cause the higher you keep the g-force durring the run the quicker the car is gona be by the way those little g-tec meters do have a full time g-force indicator in them . data loging a run with one would point out your ideal rpm range in each gear be a huge help in learning the right time to shift out of or into a gear Link to comment Share on other sites More sharing options...
Shelby Posted April 12, 2008 Report Share Posted April 12, 2008 ?? not even a (that sounds stupid .....old man ) Link to comment Share on other sites More sharing options...
TainterRacing Posted April 12, 2008 Report Share Posted April 12, 2008 I think you have a good Idea on the G-force Idea there to find out when might be the best time to shift. Link to comment Share on other sites More sharing options...
Tim_C. Posted April 18, 2008 Report Share Posted April 18, 2008 Yes, very good points as always Shelby! Link to comment Share on other sites More sharing options...
Shelby Posted April 23, 2008 Report Share Posted April 23, 2008 thanks Tim but it's not always ,, question do you or have you ever made a graft showing the lobe profile in relation to time and degrees and amount of lift on the roller and compair'd it to a stock cam profile ,, some thing has to be missing for the oem cam to out perform the roller,, it should be the other way arround unless we're missing something and i never try to act like i know it all,(altho i may sound like i am) most of the time i'm the least knowlegeable one posting but i like to move arround and look at things from a diff angle some times you get a better picture of the problem Link to comment Share on other sites More sharing options...
randomguy Posted June 10, 2008 Report Share Posted June 10, 2008 thanks Tim but it's not always ,, question do you or have you ever made a graft showing the lobe profile in relation to time and degrees and amount of lift on the roller and compair'd it to a stock cam profile ,, some thing has to be missing for the oem cam to out perform the roller,, it should be the other way arround unless we're missing something and i never try to act like i know it all,(altho i may sound like i am) most of the time i'm the least knowlegeable one posting but i like to move arround and look at things from a diff angle some times you get a better picture of the problem these cars are childish. we should all grow up. sigh :party0035: Link to comment Share on other sites More sharing options...
Dan Posted August 1, 2008 Report Share Posted August 1, 2008 Chiplee, Have you been able to further test your setup? Great info in this thread. Let's keep it alive with constructive ideas. Link to comment Share on other sites More sharing options...
chiplee Posted August 6, 2008 Author Report Share Posted August 6, 2008 Chiplee, Have you been able to further test your setup? Great info in this thread. Let's keep it alive with constructive ideas. The plan now is to have a roller cam made to 292 or slightly bigger specs. The problem is I'm in the middle of a very drawn out move from Woodbridge, VA to Ridgecrest, CA and I needed to spend 2 months in Virginia Beach on the way. Everything I own is either in storage or in the back of my 4Runner so it's all sort of on hold right now. The roller is just too nice to go back to a slip type but I want that power and torque back obviously. I'll also need to figure out just what is required to install a roller that big. If the head needs to come off then it will be a while. Link to comment Share on other sites More sharing options...
jawatech Posted August 10, 2008 Report Share Posted August 10, 2008 BEAUTIFUL! :thumbsup: Link to comment Share on other sites More sharing options...
chiplee Posted June 26, 2010 Author Report Share Posted June 26, 2010 (edited) So, ah... here's a little tasty tidbit. I think I just figured out that my WB O2 sensor has been bad, or going bad, or just generally unreliable ever since I installed the water/meth injection kit. I'm posting it in this thread because I installed that kit around the same time I installed Tim C's cam, which was the last cam in the three cam comparison this old thread was about. This means his cam might have been misrepresented in the comparison. For a while now my car just hasn't been running quite right, and recently it's gotten worse, a lot worse, like running lean and sputtering and my PLX device has just been stuck at right around 14:1. I remember it being leaner than normal on the dyno when I was testing Tim's cam, and though we were still able to tune it for the most part, it did seem like the A/F meter wasn't responding as well as normal. Even back then I suspected the water/meth mix was fouling the O2 sensor, especially since my O2 sensor is mounted way too close to the turbo, but the guys at snow performance said water was normal in the exhaust, and that O2 sensors can handle it just fine. Eventually I tried a new sensor anyway several months back, but for some reason it didn't change much. I just swapped in a new one again this afternoon and it's fixed, and I mean completely fixed. Rapid response from the PLX device and nice rich 20psi pulls, albeit on 100 octane unleaded since the water/meth bottle is empty this time. I don't know if I got a bad O2 sensor before or what, but this thing is pulling like crazy again and I love it. Long story short, I think Tim's cam might do better than it did when I dyno'd it a few years ago, and either way, I love the way my car pulls with it in. Edited June 26, 2010 by chiplee Link to comment Share on other sites More sharing options...
JayR_NYC Posted July 4, 2010 Report Share Posted July 4, 2010 well they never sent me the files but here's a look at the pull with the SAE correction factor applied. Again, to get an accurate comparison, I'll have to either make, hey wait, I have the old graph files. I'll just make them SAE and post them up for comparison. I'm a genius. I see it as 33.6HP gain for about a 2 ft/lb torque loss. Not too shabby. I bet this cam degreed would yield even more HP gain but actually start to lose some torque but I'm pretty happy with it where it is. the other thing I notice is that this cam is bringing torque on about 200RPM sooner and keeping it on about 500rpm longer, which probably explains why the car "feels" so much faster. It basically broadened the power band by 700 RPM. on the stock cam torque is above 300ft/lbs from 3400rpm to 5000rpm. with the 292 it's above 300 from 3300rpm to 5500 or even 5600 it looks like on one pull. Here's the new one with the 292 <img src="http://webpages.charter.net/chiplee/300a.JPG" border="0" class="linked-image" /> and the old one with the same SAE correction and 5 smoothing like we used today. Compare away <img src="http://webpages.charter.net/chiplee/stock%20cam.JPG" border="0" class="linked-image" /> hey chip...wats ur engine set-up????....i just want an idea how much hp my starion might have Link to comment Share on other sites More sharing options...
chiplee Posted July 4, 2010 Author Report Share Posted July 4, 2010 hey chip...wats ur engine set-up????....i just want an idea how much hp my starion might have most of the important details are in my sig. The key power parts are the tube header, 3" exhaust, O6H-20G, MPI, Roller Cam and Magna M6 head. Most of the rest of the stuff is supporting mods. Link to comment Share on other sites More sharing options...
Komeuppance Posted July 4, 2010 Report Share Posted July 4, 2010 So... supposedly someday soon start some second setup study session sans skewed sensor significance?? -Robert Link to comment Share on other sites More sharing options...
chiplee Posted July 4, 2010 Author Report Share Posted July 4, 2010 So... supposedly someday soon start some second setup study session sans skewed sensor significance?? -Robert Alliteration^5, dig it. And it's not as easy for me now that I don't live 10 miles from a shop with a dyno, but hopefully, yeah. This cam rocks. I took out the extra fuel we put in on the dyno trying to get the af ratio down and it really came alive. Was reading full "rich" (richer than 10:1) before I did that. Even at 11.5:1 it's impressive. Working fuel delivery issues now though. Link to comment Share on other sites More sharing options...
Shelby Posted July 12, 2010 Report Share Posted July 12, 2010 ok update on cars performance now with the 3:90's sounds likeit starting to come togather o you can see the full advantage of the lower gearing and what roller cam are you useing now ,, one of Tims roller 's ?? Link to comment Share on other sites More sharing options...
chiplee Posted July 13, 2010 Author Report Share Posted July 13, 2010 ok update on cars performance now with the 3:90's sounds likeit starting to come togather o you can see the full advantage of the lower gearing and what roller cam are you useing now ,, one of Tims roller 's ?? Still Tim's cam. The 3.90s are almost all positive. They do shorten the already miserable 1st gear, but they make 2nd and 3rd really really fun. Even with warmed up sticky tires on a hot day at 20 to 21psi boost a 2nd gear roll on from 20mph gets super squirrely as it struggles to gain traction. It just keeps pulling. Link to comment Share on other sites More sharing options...
Shelby Posted July 13, 2010 Report Share Posted July 13, 2010 i'm gona try and bend the rules a bit witha post i'm gona make here in this forum,,and would like your input Link to comment Share on other sites More sharing options...
Shelby Posted July 13, 2010 Report Share Posted July 13, 2010 well made the post, internet hic up'd and 20 mins work gone http://www.starquestclub.com/forum/public/style_emoticons/default/blink.gif Link to comment Share on other sites More sharing options...
chiplee Posted July 13, 2010 Author Report Share Posted July 13, 2010 well made the post, internet hic up'd and 20 mins work gone http://www.starquestclub.com/forum/public/style_emoticons/default/blink.gif Ack. I hate that. I really wish the boards were able to retain field inputs when you click the back button. Actually I don't know if that's a board problem or a browser problem. Link to comment Share on other sites More sharing options...
turbosigma Posted July 13, 2010 Report Share Posted July 13, 2010 Quick Question :- Does your roller cam still stick out the back of the head? The stock magna had it to drive the water pump. I'm using it as my cam trigger to the ecu, so still need it. Link to comment Share on other sites More sharing options...
chiplee Posted July 14, 2010 Author Report Share Posted July 14, 2010 Quick Question :- Does your roller cam still stick out the back of the head? The stock magna had it to drive the water pump. I'm using it as my cam trigger to the ecu, so still need it. No, but I've had a few custom cams that came with it. The blanks had them because they were for caravans and other stuff too. I always just cut them off or got the caravan seal. Most all of the cams available are regrinds now, not cut from blanks. Link to comment Share on other sites More sharing options...
Recommended Posts