Title: Has anyone any thoughts on using the FK89 2° retarded? Post by: Jon on August 16, 2007, 11:52:03 am To me it looks like a good idea, might loose a few ponies on the top, but looks to gain more in the low to mid range.
Heavy street car with occasional racing. Heads are modified 48x40 CNC. Volume 78.4x94. CR 11.5:1 And what's the tightest quench height you have used with a DMS full race crank? Title: Re: Has anyone any thoughts on using the FK89 2° retarded? Post by: Diederick/DVK on August 16, 2007, 12:40:24 pm don't you mean advanced to gain more bottom end?
or am i retarded? ;D Title: Re: Has anyone any thoughts on using the FK89 2° retarded? Post by: Jon on August 16, 2007, 13:37:16 pm I have had best results with retarding, but I might be wrong... thats why I'm asking ;-)
Title: Re: Has anyone any thoughts on using the FK89 2° retarded? Post by: Jon on August 17, 2007, 13:13:57 pm To tell the truth I have only played with this in the engine analyzer software. And I got a boost in power in mid and low rpms with a 2° retard. But after reading your thoughts on it and reading a lot of other internet articles on the subject it just doesn't add up. Some how i got the opposite result.
This calls for more investigation and wrenching... Thanks!! Title: Re: Has anyone any thoughts on using the FK89 2° retarded? Post by: Harry/FDK on August 17, 2007, 14:42:12 pm Come on guys, more... I love to learn from this stuff. ;)
BTW, Jon any REVESTREKER news ? Thanks, Harry Title: Re: Has anyone any thoughts on using the FK89 2° retarded? Post by: louisb on August 17, 2007, 15:16:18 pm This is an interesting conversation. I have an Web 86B (sorta like an FK8) that is ground 112. The seller recommends running it retarded 4 deg sayings it will act like a Web 86C. I have been trying to decide if I should run the 86B retarded or just step up to the 86C.
--louis Title: Re: Has anyone any thoughts on using the FK89 2° retarded? Post by: Shubee2 (DSK) on August 18, 2007, 04:09:29 am To tell the truth I have only played with this in the engine analyzer software. And I got a boost in power in mid and low rpms with a 2° retard. But after reading your thoughts on it and reading a lot of other internet articles on the subject it just doesn't add up. Some how i got the opposite result. This calls for more investigation and wrenching... Thanks!! I hear Cedor advances his angle 110 cam for his name taking, ass kicking motors too. ;D Title: Re: Has anyone any thoughts on using the FK89 2° retarded? Post by: stealth67vw on August 18, 2007, 06:29:01 am He prolly uses Mountain Motor (tm) heads, hand ported with a lava rock epoxied to a drill.
Title: Re: Has anyone any thoughts on using the FK89 2° retarded? Post by: Jon on August 20, 2007, 07:36:22 am Wow... Cedor too... that makes two of you.... :o
Its a good think I asked you guys, cause it seems like I have taken a short cut in testing out advancing. Compared to 2° retard there was more to gain in drivability at 2° advanced. But that meant that I had to re-dial the cam for the sixteenth time, I even had to make new special offset disks to get it just right. A lot of work, but it felt rewarding in the end. I also got the squish height adjusted to 1mm, btw, rimcos decking was of by 0.31 mm but it was at lest parallel to the crank. Thanks for the tip... and the free torque ;-) Title: Re: Has anyone any thoughts on using the FK89 2° retarded? Post by: stealth67vw on August 20, 2007, 07:52:17 am I was playing around with Desk Top Dyno yesterday and it showed about 8 more horsepower with 4 degrees retarded with my combination but I know other wise. In past experimentations with my highly calibrated Butt(tm) Dyno ;D, my motors have like advanced valve timing. I usually run straight up to advanced 2 degrees for reasons Jim has mentioned. He's a fart smeller, I mean smart feller and his thinking makes logical sense.
Title: Re: Has anyone any thoughts on using the FK89 2° retarded? Post by: javabug on August 21, 2007, 17:43:00 pm On almost every VW motor I have built in the last few (5-7) years Does this apply to most cams across the board, or only ones with certain lift and duration measurements? I'd love to apply this to my stroker when the time comes...hopefully sooner rather than later. Title: Re: Has anyone any thoughts on using the FK89 2° retarded? Post by: javabug on August 21, 2007, 20:37:29 pm Thanks Jim. I know its not an exact science, and if something that works on your combo will work on mine is a pretty vague question until tested.
Title: Re: Has anyone any thoughts on using the FK89 2° retarded? Post by: Jon on August 22, 2007, 10:10:55 am That's why I like Engine Analyzer, don't have to do any math. ;D
Sure you spend a good few hours measuring everything and you need real flow data on both carbs and heads, but in the end it hopefully saves you the irritation of building a engine that's way of... and perhaps a few bucks too. I have tried Desktop Dyno to, but I have to say it feel like Mickey Mouse compared to EA, there is not half as much data going in to it, but I hear the result are pretty close to actual dyno testing. As the makers of EA is very clear about, this software is no "proof" of anything, it just gives you a trend... you see what way you are moving... Sure, nothing can replace real life testing and experience... but EA can replace the calculator at least :) My last engine would not rev past 6000, it was always a mystery until I entered it into EA.... just a bad combination of parts, but it still did 13.5 at the quarter mile. I think its a good tool for us new beginners at least... http://www.performancetrends.com/EA30.htm (http://www.performancetrends.com/EA30.htm) Title: Re: Has anyone any thoughts on using the FK89 2° retarded? Post by: Jon on August 23, 2007, 07:11:29 am It was a 78.4 x 94 with a FK 89 advanced close to 2°, Super flow heads with 42x37 flowed 190 cfm at 25" H2O, 5.4 rods, 10.5 CR, 3!! mm squish (came down from 13.5), IDAs tested with both 42 and 45 venturis, perfect lambda. 4 kilos flywheel and magneto. It pulled super strong up to 6000 rpm where it produced 183,5 hp with a max of 220 Nm, I loved to drive it on the street, just easy to drive. Had it on a chassis dyno and I saw an extensive fuel stand of at 6000 rpm, with fuel comming up of the jet holders in squirts. Seemed like it had reversed pulses at this rpms.
Title: Re: Has anyone any thoughts on using the FK89 2° retarded? Post by: John Rayburn on September 16, 2007, 06:26:19 am I would personally never run an 89 in a heavy street car even with 11.5 cr. It's just too much duration. I'd keep the advertised around 310 at the most, and a rod ratio in the mid 1.6's. I've always trusted the cam grinder and set my cams straight up. It's best to build in as much torque as possible to get your heavy car rolling.Good luck!
Title: Re: Has anyone any thoughts on using the FK89 2° retarded? Post by: AlGhia on September 16, 2007, 09:56:35 am Interesting thread this especially as anything to do with cams is a foreign language to me. I recently changed my cam from an FK89, seemed very flat in my 2161 ghia. Got a custom grind cam on recomendation but it does not want to rev past 6000rpm, so I have been tryin to learn what the specs mean. Cam duration is 296 and intake lift is 545 on 1.4 rockers, grind is vw190-107deg. There is more info but I am lost.
Any ideas what this means, apart from the fact I have an FK89 table lamp now ;D Title: Re: Has anyone any thoughts on using the FK89 2° retarded? Post by: John Rayburn on September 22, 2007, 09:54:21 am I'm always suspicious of a cam refered to as a "special" grind.
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