Correct.
Did you notice anything wrong with my math?
Time to go Stage II!
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Did you notice anything wrong with my math?
X2
When and if you do this and make it live then i will believe your a super tuner and you will get my respect. I would never challenge your ability as a tuner again
That's alright, Gene. It doesn't bother me what others think of me. I just hope someone is picking up something useful they can use, or I'm just making something that they've always wondered about clearer to them.
That's alright, Gene. It doesn't bother me what others think of me. I just hope someone is picking up something useful they can use, or just make something that they've always wondered about clearer to them.[/quote]X2
When and if you do this and make it live then i will believe your a super tuner and you will get my respect. I would never challenge your ability as a tuner again
I respect that.
What about the 1200 RWHP Cal asked you about? Will this be your goal?Dusty Bradford
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- May 24, 2001
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Yes. It has to do with the average hp put to the tires through the entire pass. If having 4% slip requires a motor to drop 2000 rpm on the gear change it may run slower than a converter that drops 1400 rpm and slips 8%. If you had dyno numbers on a combo such as this you would see the average power was lower through the pass from it falling to much on the gear change.
There's a problem with the equation you're using.Wow! I guess I missed a lot today. Slow morning at the shop, Donny? You missed the point of my post. Much like your SIM, I can juggle the numbers however I want. I could say your making 857 rwhp and the engine is making 30% more 857 X 1.3=1114hp OR I could say that the calculator is actually off 5% the other way rather than only running the variables only in one direction. I just wanted to make sure 5+bhp/cid is your bottom line
Are you expecting over 1200 rwhp with new combination?
Are you changing the convertor or are you hoping the extra rpm's will help it couple better with the extra 400hp it will be seeing?
Why are you willing to take the new combination to the dyno when you were so against taking the old one, especially as hard as we tried to convince you of the benefits of going?
857 x 1.3 = 1114 Not correct.
857 / .7 = 1224 Correct.
Two very different results. My equation is adding back in drivetrain losses. The other equation is only adding back in 30% of the 857. That's not the correct answer for what we are trying to examine, which is drivetrain losses.
If you're going to show incorrect equations, you should at least explain to others why it's incorrect to prevent confusion, or the spreading of incorrect equations for coming up with drivetrain losses.
Question 1: That's a little high.
Question 2: I'm going to start off using the same TC. I think it's going to be real close to what the new engine will need. I do expect it to couple much better with the extra rpm. Slippage may still be the same, though.
Question 3: You didn't need to convince me of the benefits. I realize it will speed tuning along. I just wanted to see what I could do without a dyno. I did grow up in a time where dynos were not very common and I managed to tune my high school racer to an impressive performance level without a dyno.
I guess I just wanted to prove to myself that it could still be done with all the electronics. I proved it can be done very effectively, but it was more difficult than it would have been if I had used a dyno. It required me to think up some very interesting ways of loading the engine.
Besides, I experimented with countless fuel curves, since I was learning how to pattern just a basic, well working fuel map. If I had to pay for all the dyno time that my car would have been sitting on the dyno while I re-patterned the fuel map to try a different tack, I would have spent a small fortune. Figuring out a way to tune the car without having to use a dyno did pay off not just from the money I saved on dyno time, it allowed me to really take my time with my experimenting with the fuel map, not feel rushed, and really learn what didn't work and what worked better.
My experience tuning my car without a dyno came in very handy when I lately had to tune a car on a caribbean island where there was no dyno to be found on the island. About three runs down the track and the tune was at a point where I could give the owner instructions over the phone as they moved the boost up higher, after they removed the intake and sent it to me so that I could fix the aux fueling system for them.
There was another tuning job I did where the owner of the car insisted that the car not be put on a dyno. That was another situation where the time that I spent tuning my car without a dyno paid off.
The reason for putting this new build on the dyno, is just because I'm real curious to see what the numbers will be with this build. Especially after getting the surprise I did with the last engine. When I pulled off that 8.7 with the Stage I, you have to realize that not only was the fuel ratio leaning, but even more surprising is that I had a few cylinders that had been leaking down a lot. One cylinder was leaking down about 60% for a year before that run. At that point, when I finally realized that I had something pretty unique, why torture the engine on a dyno just to get a number when you know you have multiple cylinders with big leakdown numbers? It just didn't make any sense to me. I would end up with a dyno number that would have not been a true representation of what the engine was really capable of putting out had the engine been in better working order, and the tuning was basically done.
So even though you might not be getting as much hp through the TC due to the additional slippage, you are getting a better avg. hp through the gear changes due to the better fitting rpm drops.
What are you predicting for RWHP?
Inquiring minds what to know..
[/quote]We already know that I'm hoping for 1,530 bhp.
The big question is, what is my drivetrain losses percentage? lazaris has given us his estimation of a range for drivetrain losses with an automatic. My range is a little different. I am by no means an expert on this subject, but I feel that it is possible to have more than 22% drivetrain losses. I have no data to back up that assumption. I just have a gut feeling about it.
I'm going to use 23% for drivetrain losses with the present TC that I plan on using.
1,530 x .77 = 1,178
Dusty Bradford
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Yes. The goal is to keep the engine is it's sweet spot for most of the pass. If it really makes power from 7000-8000 you don't want a super tight converter that drops the rpm down to 6000.
I was thinking of moving to a 3.42 or 3.55 gear, but I think I'll start out with the present 3.73 first. They're in the car, might as well see what the car can do with them first.
You finally understood my point. Much like with your Sim, numbers can be manipulated. Why do you think you were "surprised" & "doing the impossible" and had to keep modifying the Sim and lowering your HP/CI?
Bottom line with me will always be the time slip.
Bottom line with me will always be the time slip.
lol What? I finally understand? As if I finally had a revelation, an epiphany that a sim is not accurate. Com'on. After playing with sims for over 14 years, probably closer to 20, you really think that I finally figured that out through the grace of you showing me the light. Shows what you know about me, Cal. Not much, obviously.
You and I agree on one thing, I suppose. In the end, it is the time slip that counts. I do have plenty of those.
Next time you get the feeling for playing with numbers, make sure you use the right equations, OK?
I already know that Tony thought the calculator was low (conservative) by maybe up to 5%.
I'm just curious, Gene. The above statement you made. Which figure did you find to be lower by 12 hp? Was the dyno number lower? Or the calculator number?
The HP calculater says 1062 RWHP
Using the dyno numbers and weight the et calculator says 7.81 at 174.3 Mph Pretty dam close..Real time numbers are 7.72 175 Mph and dyno number is 1050 RWHP.What sort of tires did you use on the dyno?The HP calculater says 1062 RWHP
ET streets and used them the rest of that year at the track. I put Good year slicks on this year and picked up .07 in 60ft
I've seen the videos of your car on the dyno. Those big tires were ET streets? I saw another early video where it looked like the Goodyears were on the car before the car was even finished.
I'm just learning here, so excuse me if I come up with questions that seem elementary. Don't big oversized tires on a dyno eat up some of the rwhp?
I knew what I was doing, I guess you can't grasp my point
Example: You're now going with the low end of your hp spectrum and your "gut feeling" has drivetrain loss creeping higher. What is the ci of your new combination?No, I guess I didn't grasp your point. Usually when someone presents an equation, it's because that's the equation they're used to using. I could only assume that, since you seemed to consider the correct equation, the one I presented, to be funny math. I still don't know where you pulled those 30% drivetrain loss and 30% TC slip figures from. Anyway, I'm glad that you do actually understand that my math was correct. You really had me going there.I knew what I was doing, I guess you can't grasp my point
Do you blame me for making my realistic goal 1,530? Do you think I'm wrong for doing that? Do you really think the higher end of the range is more realistic? Is the higher end number the one you're hoping for?
Drivetrain losses. What do you mean I'm creeping the number higher? Higher than what? Higher than someone elses estimate? When did I actually make a guess about what my drivetrain losses are before I stated the 23%?
The new cid will be 228.07. Just a slight bore and hone for the new pistons. Same short stroke.
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