There use to be a 500 hp 355 at 2600 lbs race car. It would hang with 430 challenge cars. The sound was insane!!! http://youtu.be/lDicz7UG5HY
Adding lightness is always a great answer. The most powerful car that I owned (which was not all that powerful) had only 320 HP at the rear wheel and weighed 2200 lbs. Unfortunately, I was limited to a very small tire (235/50R16) and as a result it would leave rubber everywhere. On the dragstrip it was respectable for a street car (12.76@115mph), but it was very quick on a relatively short track (6 speed gear box [4th was 1:1]- w a 3.606:1 rear end).
Over the last 3 years I have been going to COTA (Circuits of the Americas) with the PCA Group down here in Texas and each year my driving skill improves. The car has slowing gone from Street to Challenge (minus the solid bushings & Exhaust). We return this May with Fabspeed race headers + Full Challenge Exhaust. This should be an exciting development as I have data for all 3 years and after this is all said and done I will post the gains. We all want more torque if were racing out on track, all modern Porsche's & Ferrari's just launch out of the turns and there is no way the F355 can improve on that to catch them. Weight reduction would be the only answer to improve should you want to do that. Not me. I've been in a 2016 Cayman GT4 with serious mods and it's FAST! I will be running with standard Cayman GT4's to see just how well it is compared to my 355F1. Can't wait! To me the mods you need for sure are: 1. BMC air filters 2. Fabspeed secondary Cat Bypass 3. Cat Bypass pipes Here is my vid chasing a 2004 Porsche GT3 last year. https://www.youtube.com/watch?v=1Ak3TPVuisM Ciao, Stanislaus
Dynojet Reserch: Red curve: Stock 355 with sport exhaust : 301 rwhp Green curve: F430 Challenge : 428 rwhp Red curve: F355 Challenge : 400 rwhp Image Unavailable, Please Login
The stock seats are nearly 50 lbs each, you can get seats that weigh 1/2 that easy. The stock muffler is also 50 lbs and is a boat anchor. I think that I am probably somewhere between 250 and 300 pounds lighter than stock right now (not counting the turbo system). I am hoping for about a 10% overall weight reduction when I am done with it. That's without any exotic materials like carbon fiber. I would be happy with 2800-2900 lbs (although less is always better), unfortunately some of the parts going in are not going to reduce weight at all. The turbo alone is a 35 lb brick and there is no way to change that.
Amazing power from that F355 Challenge. For the record, my F355 Challenged dyno'd 292 RWHP on a Dynojet near me. I would love to get an extra 100 wheel HP. Any idea what they did?
Yep I replaced them with modern Sparco EVO seats and it's got a Tubi which is being replaced for a Challenge Race type. At some point I would like to make as many of the OEM Steel brackets into aluminum, sure it might not be as safe but, it's my car for the track. An extra set of doors with all the guts taken out would be nice for track day, then swap the loaded one back for city usage... sounds like to much work! ;P) I should get a lighter battery as well.
I would like to get mine dyno'd to see what I got? Would really like to get the GruppeM intake but, the price is just hard to pay!
From reading this thread, it appears many of you are looking for torque. Bottom end grunt. Trouble is the 355 engine is just too small to provide it. It's a tiny little thing at 3.5 liters. Give it a break! She is working awfully hard as she is in stock form!!
Slightly disagree, the motor just needs a little bit of boost and higher octane fuel to make a boatload of torque. Anyone who thinks that you can't make a ton of lowend torque from a 3.5 liter motor needs to drive my F150 with the 3.5L ecoboost motor. How you accomplish that is a matter of personal preference. A positive displacement 2.3 liter/rev twinscrew supercharger would certainly wake up the motor down low. A pair of small turbos would likely do the same. The problem is that at a compression ratio of 11:1 you have to either get higher octane fuel or decrease the compression ratio of the motor. Although, no one has suggested it, you could even boost low end torque by adjusting the valve timing at the expense of high end power (unless you retrofit some kind of variable valve timing, complex and expensive). Sent from my SM-G920P using Tapatalk
I had a huge amp and sub box in mine. Took it out and car felt like a passenger got out 40 pounds you will feel a difference. One of my challenge cars is stripped to the bone, it feels lighter pushing around then a full dresser Harley. Loosing all the weight you can really adds up fast in these cars
I found a number of dyno sheets on the web. The problem is comparing different sheets from different machines on different days. When I looked at various sheets on the web the majority were in the 290-300 rwhp on a Dynojet and 320-330 rwhp on a eddy current dyno (Mustang, Dyno Dynamics, etc). I prefer the Dynojet because there are limited ways for the operator to play with the numbers. The eddy current machines can be made to read whatever the operator wants them to and requires some guess work in the input stage (ie: car weight, etc.) The Dynojet is just a big roller of a known weight that spins and the power is calculated by how fast the roller is accelerated and spun.
Took 70 lbs of sheit out of my car when I yanked the sound system - honestly who installs that crap in an exotic performance car?!!! Then replacing the stock exhaust system with Goth's saved me another 35 lbs. 105 lbs lost baby. Woke the car up like you could not believe. That is the equivalent of adding 10 HP. Which brings me to anther subject - observed HP. You can add HP to the engine, but the net effect of it on the chassis, especially one that has been lightened, is not reflected. This is where observed HP comes in. I added about 23 HP to my engine on the dyno, but lost over 100 lbs. This translates to a 33 HP gain. Plus, my Serie Speciale has Kevlar seats that save about 75 lbs over stock. Performance-wise, my car should reflect observed HP of around 40 HP over a stock '93 or '94. Compared to an earlier model, my engine has more HP and a more aggressive drop gear, so that would add more observed HP. In theory, at the track, my car should perform like a stock early 348 with about 50 more HP. But this is all theoretical. The point is that we shouldn't get hung up on the absolute numbers. It's more about how the car performs under the same conditions as compared to before the modifications. This is where a drag race scenario makes more sense for this test. Cornering is great for track events, but won't give you a clear indication of observed HP. Let's talk dynos. There are several different models we have seen used by the Brotherhood and the results are widely ranging. It matters little what number you get. What matters is the difference in the numbers after your modifications. If your Dynojet measured 254 stock and now it says 284, that's pretty damned good. Put your car on a Dynopak and it may read 300 HP. A Mustang might show 290. Who cares?! Just be consistent with your use of dynos. Even if the input data is entered wrong, as long as the same data is used in your before and after runs, it works (sort of). Optimally we would want the inputs to be as accurate as possible, however. We are after the before and after numbers, not who's car measured the most. Except for Ernie, of course.
I think it matters to establish you have a good baseline. If you put the car on and get 254 and the next time it gets 284 after some mods, but in reality you just didn't have a fully seated sensor or you did a major that fixed cam timing that was off, you'd delude yourself into thinking you gained 30hp from your mods when you actually just fixed a problem on the stock vehicle and gained nothing from the mods. As temperamental as these cars can be, I think it's important that your baseline number is correct or in the ballpark.
Having actually owned a shop and done a considerable amount of dyno tuning, I would say it is critical that you have a dyno that is repeatable and well calibrated to the conditions, and the only way to ensure that repeatability (at least until you have considerable data on the dyno and how the operating parameters affect it's readings - like altitude and weather corrections) is to have a consistent test mule that you can use to sanity check the machine (along with the proper calibration tools to set the dyno up correctly in the first place). Dyno calibration is critical when you have significant time intervals between testing. As noted above, if I wanted to, I could have made my dyno spit out whatever numbers I wanted (I had a Mustang MD-250). To be honest, the numbers being spit out are really unimportant, it's the consistency of the machine's measurements that matter. The numbers are just relative, and don't mean anything meaningful except in relation to themselves and only if the machine is consistently able to measure the output of the vehicle strapped to it. Properly calibrated and properly corrected, the test mule should put down the same power number every day (within a reasonable margin of error) assuming that the motor is operating at steady state with all components appropriately warmed up.
Good luck on getting Kip.........he is a no show kinda guy. I remember that even Bill said he was a nightmare to get anything done for that car him and David C. built. Maybe years later he has changed his business practice.
Did you stop to think why they weigh so much? There is a very good reason seeing that you have a Spider. If you know how to modify your car(it will no longer be a functional Spider) you can put in a regular cf race seat.
I know all the secrets used to build that engine with the exception of the Motec engine management data....which by the way requires you to plug in your lap top at every race to re-tune for current conditions....that is how things are when your engine tune, to achieve that level of hp, is so close to the edge of extinction. You also have to bring your "A" game when modifying the monocoque chassis to get under 2600lbs wet........it is bad news to find your construction mistakes only after wrecking at race speed.
Would that engine build benefit from running a much more modern ECU? Would it make it streetable or would it simply be too aggressive?
The MOTEC unit they were running was a current up to date system......this engine build/tune was way to aggressive to run on the street. You could de-tune and make it streetable but would loose that high hp/torque number. The engine mechanicals were very good.....close to a TODA but did not have the TODA modified cams(lift/duration).
