197.6whp @ 8250 rpm...NA...

I

Installshield 2

Gothenburg Superiority
well guys, I finally got the engine in temporarily in and running...

I was awarded one pull at Penn State's college of engineering chassis dyno on Sunday the 22nd (other than the couple to tune it)...The system runs just like Penn State's motec controled brake dyno if you remember the past threads I made about the engine. it uses MS Excel to create a graph, which is similar to any commercial dyno. I have no indication of how high or low this dyno reads, I have never seen any other cars used...but I saw from the graph that it correctly uses the function to determine hp...197.6whp @ 8250 and 148.2 lb/ft @ 4200 rpm (steep curve, I know)

I hate to hurt my own credibility, but I have not yet been emailed the graph yet...the printer for the graph had been malfunctioning that weekend, so they said that they would just email the file...I will post it as soon as I get it hopefully this week...

Also this thread will go through every single modification made...

I also got to run a 1/4 mile once...more on that to come...Andy, I think you will like it...

but the engine computer was only borrowed, I haven't got to purchase mine yet...we installed a Motec and utilized only the very essential sensors and ran a seperate MSD ignition system for the dyno...we tuned it on the dyno for just WOT...the alternator was completely left out of this equation...the belt was still on, but the drain was entirely on the battery...after the 5 or so tuning pulls, we had to recharge the red top Ultima...so realize this whp number is with absolutely no alternator load whatsoever...the stock ecu was pulled an we used a fully custom harness for the essential triggering and stuff...no light, no dash functions (guages, stock tach, we ran an autometer comp tach off the crank triggering with its own power source so I had an idea of rpm just for safety)...the car was totally undrivable other than that...we just briefly street tuned it to check if the 13.1:1 compression was even feasible for street use...we kept it rich for safety, and ran out of time before we had it towed to the track...

this was only the beginning...that peak hp will be far less for street use simply because I am parking the fuel cut right at 8000 rpm...until I do something about the crank...I am looking for 180whp for street use, a little more is fine...but I have to have the reliability...

sorry gentlemen...comment away...I will have all the information anyone needs in days to come...my senior thesis is due tomorrow at 330 and until them I can't really justify being on here typing huge threads and stuff...I will check on often (I have to be up all night anyway) and answer questions...but I don't have time to list everything done to the engine and evereything until this weekend...
 
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omg wow. nice stuff. damn 8250rpm huh. some serious work to let that puppy breathe.
 
haha FB...your source is now a traitor...no its no big deal, I just wanted to wait until My Exedy clutch is installed and I have my own ECU to test it...

also, technically I wasn't driving...my friend from school was, I just mpeg'd it...that should be up soon hopefully when he gives me the slip and the camera...so without the slip, I can't even remember the exact time and mph...I know it was a poor launch though, like just under 2.5 60'; and also that the car was right up on 97mph or so by th end...


just so you know he let me in on some secrets of your own too (naughty)
 
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stock crank yes...but cross drilled, slightly knifed with new close tolerance custom bearings...The crank was then rebalanced after we determined overall mass of the assembly...In all honesty, the crank more or less has a relatively easy time with this from what it appears...the weight savings, and slower piston acceleration because of the higher rod ratio of the new assembly put relatively insignifant amounts of additional stress on it (hopefully)...so aside from the increase of about 40 lb/ft of torque and its torque rate (i.e. HP), it isn't seeing as much additional stress as you would think...

head wise, its a "stock" FS-DE head...and obviously a bunch of other stuff...as far as running equipment: two custom cams, Eibach spring kit, stock valves but 3-angled, and shims for correct lash...The head recieved polished exhaust ports as close to stock as possible (obviously some is removed to mirror it) and some porting and deburring of the intake ports...the intake manifold was port matched and has the VTCS removed...but a J-spec intake manifold is on the way anyway...

the rpm is simply the rods and pistons though, aside from the valve springs...a custom 8mm iirc longer than stock rod was used with custom pistons with tiny ass crowns, swedish gapless rings, and a custom 19mm titanium wrist pins (two mm above stock)...the rods and pistons were both cut out of forged aluminum for weight savings. the static CR is 13.1:1 and affective rod ratio is up to about 1.54...

the engine produced a max of something like 218 SAE BHP on a brake dyno nearly two years ago...its just finally in the car...refer back to those threads though also for more info on the build, I may have used some wrong numbers because I haven't really needed to talk about this since then...but in a nutshell, longer rods, moved the piston pivot up on the custom pistons to maintain deck height, and put a channel under the piston crown to allow the thing to still pivot correctly...

reliable? not sure yet...but revs will be cut down a few hundred rpm for street use to at least help...the high compression and small crowns makes this thing somewhat of a rotary engine in terms of detonation...i.e. it hates it, and one bad one may do it in...so I am taking the tuning of this thing extremely seriously and slowly...
 
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That is so awesome :D I'm glad to hear you are making progress, especially where not many people want to touch. Perhaps you will help clear the way, slowly ;)

Can't wait to see updates in the future!
 
So are you using the stock valve locks/retainers? i know earlier you said it was the eibach springs, do you have the specs on the cams? were they sent to crower for there regrinding process? What size exhaust are you running? were the pulls done in 4th gear or 3rd? was this on pump gas?(91 or 93) and What was the a/r ratio around for the dyno?(12.5:1 or around 13.0:1) What was the overall spark advance around? sorry for all the questions but i am trying to get some more knowledge for the future...
 
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