This is probably going to be a long post. Anyway-- dyno day today, and it was a mixed bag.
Results were good, however not the improvement I was expecting. Part of this has to do with 1) an underestimate of my engine as it was and 2) whatever problem sucked 90hp out of the equation between the dyno room and the drag strip.
I am happy that: I prevented catastropic engine failure ahead of time (my springs were installed .100" off, each one, giving me about 100lbs on the seat), and the valves were rotating in their retainers bad enough to really muck the locks and retainers. I am also good to know that my 20" case 4-year fiberglass blowout dynomax super turbos make just as much power as smaller, louder mufflers.
The engine idles very smooth at 1000rpm for the size of the cam (287/291 256/260 .643 112 (the 113 turned out to be a typo)). He said probably 900 rpm in gear when it gets back in the car.
I don't have a graph with me, but the general jist of things was about 555-565hp @ 6000(depending on which dyno test, I didn't stick around for the final pulls) hp, and 500-550 ft-lbs of torque from 2500-6000, we ended the highest dyno pull at 6200. No more clicking hydraulic lifters.. Once I get some info from the website I have on a few things, I will host video from today, nothing special, but an x-pipe exhaust connected to an engine...
the engine is very sensitive to jet changes, could care less about timing from 34* to 40*.
The shop that did it says a stick car behind an engine that has been on their dyno makes about 30hp less on the chassis dyno, which puts this engine, I think, at about 510ish hp @ the rear wheels.
The chassis dyno is up in the air, the shop has less time to finish my cam swap, the chassis dyno is in a city that is closer to me than it is to them, so I may do it on my own.
I know there will be serious disagreement (I think anyway) about his "engine dyno" to chassis dyno theories, but, I understand where he is coming from and why and think they are pretty on spot.
was the 20hp and 25 ft lbs worth it? not sure, probably not, but like I said, if I knew the engine really had more guts to it..
I got to see how quick the engine would run through the gas from the accelerator pump and bowls, so I am still pretty confident that it was a fuel delivery issue that slowed me down so much. We have not ruled out a bad torque converter killing me all along, but...

All I have to say is that that the hydraulic roller was extremely competetive at this rpm range, and I'd probably do just as well since my max RPM for any real reason is 6000ish, but... no more clicking lifters.

Ok.. long message.

Night folks..

Matt

Originally posted by MadMarv:
This is probably going to be a long post. Anyway-- dyno day today, and it was a mixed bag.
Results were good, however not the improvement I was expecting. Part of this has to do with 1) an underestimate of my engine as it was and 2) whatever problem sucked 90hp out of the equation between the dyno room and the drag strip.
I am happy that: I prevented catastropic engine failure ahead of time (my springs were installed .100" off, each one, giving me about 100lbs on the seat), and the valves were rotating in their retainers bad enough to really muck the locks and retainers. I am also good to know that my 20" case 4-year fiberglass blowout dynomax super turbos make just as much power as smaller, louder mufflers.
The engine idles very smooth at 1000rpm for the size of the cam (287/291 256/260 .643 112 (the 113 turned out to be a typo)). He said probably 900 rpm in gear when it gets back in the car.
I don't have a graph with me, but the general jist of things was about 555-565hp @ 6000(depending on which dyno test, I didn't stick around for the final pulls) hp, and 500-550 ft-lbs of torque from 2500-6000, we ended the highest dyno pull at 6200. No more clicking hydraulic lifters.. Once I get some info from the website I have on a few things, I will host video from today, nothing special, but an x-pipe exhaust connected to an engine...
the engine is very sensitive to jet changes, could care less about timing from 34* to 40*.
The shop that did it says a stick car behind an engine that has been on their dyno makes about 30hp less on the chassis dyno, which puts this engine, I think, at about 510ish hp @ the rear wheels.
The chassis dyno is up in the air, the shop has less time to finish my cam swap, the chassis dyno is in a city that is closer to me than it is to them, so I may do it on my own.
I know there will be serious disagreement (I think anyway) about his "engine dyno" to chassis dyno theories, but, I understand where he is coming from and why and think they are pretty on spot.
was the 20hp and 25 ft lbs worth it? not sure, probably not, but like I said, if I knew the engine really had more guts to it..
I got to see how quick the engine would run through the gas from the accelerator pump and bowls, so I am still pretty confident that it was a fuel delivery issue that slowed me down so much. We have not ruled out a bad torque converter killing me all along, but...

All I have to say is that that the hydraulic roller was extremely competetive at this rpm range, and I'd probably do just as well since my max RPM for any real reason is 6000ish, but... no more clicking lifters.

Ok.. long message.

Night folks..

Matt Sounds good. Keep up the good work and let us know how things turn out graemlins/beers.gif

The shop that did it says a stick car behind an engine that has been on their dyno makes about 30hp less on the chassis dyno, which puts this engine, I think, at about 510ish hp @ the rear wheels.
You are going to lose alot more than 30HP between an engine dyno and a chassis dyno/drag strip, 15-20% loss should be expected,and is reasonable...that's why we don't race dynos. HP and Torque numbers mean nothing, give me a timeslip everytime graemlins/thumbsup.gif

Matt,will you be ready for LVD next Sunday?

I don't think so Chris, I think we found another piece of the puzzle, the converter spit its innards into the transmission so right now I have a 12" loaner from teh trans place to use, plus I haven't been able to inspect/check everything else on the car.

Rapid Robert, I know we don't race dyno's but the way I got explained it is that the gross percentage theory of HP loss is essentially junk. It is just people who get "650 hp" on a engine dyno then get "460hp" on a chassis dyno were never making 650hp.. Now, if you were to ask me right now if I really think it is making that much power at the rear wheels I'd say no, but if the dyno operator is being honest about how he is doing the run, then you consider the fact that my exhaust, with my mufflers, with my accessories were running on the engine, the picture becomes a little different.
This guy has done alot of very high hp blown motors and says without alot of fanfare that behind a stick most of his motors never make more than 30hp less on a chassis dyno.
I don't think its a linear function, a ZF 6 speed takes x horsepower, and a 12 bolt takes y horsepower, and overcoming rotational masses at the wheels and other resistance takes f hp and that x, y, and f are always the same in any car behind any motor that uses those components, but I don't think its correct to say that a total driveline loss of 15-25% can just be given out.
I am considering a chassis dyno to see what the story is, a better way to get this figured out would be a run at the track, but the shop still thinks I should invest in or borrow an A/F meter.
Everyone is entitled to their view on parasitic driveline loss, I am not sure I am in this camp quite yet anyway but we can all think different about it. I think he has tested enough engines on his dyno to know what a stick shift car will have for a loss to a chassis dyno.

Time to make a phone call..

Matt

Matt,without considering HP,what is your ET goal with this car?

11.5x-11.99 in "as is" street trim.

I pulled a 12 flat at LVD last year, even if I just got 20+ hp from a cam swap and I really am not going to "find 90" (i'm not so sure myself..), I am pretty sure my ET streets are out of the question because I'm not roll bar legal...

So I redid my goals to just pull up to the track and click of a sub-12..

I don't really care what the numbers are either, he said with a velocity stack, using air from outside, running a faster test (400 or 500 rpm a second) and dragging the engine down from RPM (a la a magazine test) I could stick 80-90hp on what I had. So its sort of a pointless #, and from what I gathered, chassis dyno's aren't so useful for automatics either...

matt

Marv,

I would agree that many people over-estimate their HP. However, I strongly dis-agree that a 550-560 flywheel HP engine will only see 5-6% loss on a chassis dyno. There is no way, I've done way too much chassis dynoing.

The only way this could happen is if the engine dyno is underestimating the HP and the chassis dyno is over-estimating it. Also realize, they can make these dyno's say whatever they want by entering different correction factors.

Jody

Originally posted by MadMarv:
It is just people who get "650 hp" on a engine dyno then get "460hp" on a chassis dyno were never making 650hp.
Matt I may fall into this category. My car weighs 3,700lbs on a digital scale with me in the driver's seat. My car only made 464RWHP, but a staggering 587ft lbs or torque! Sure, you can say that the torque numbers are exaggerated by the converter, but at the end of the day 587ft lbs is what the tires are seeing. I don't know if my engine makes 650HP, but I do know it runs 10.60@127 in the right conditions. Take the dyno stuff (engine and chassis) with a grain of salt. I've made 50 or more pulls on two different chassis dynos with my car and the numbers are never near what I would have expected based on the cars track performance EVERY weekend. I only use the dyno as a tuning aid to tell whether the changes I'm making are adding or removing power.

Matt,seems to me you're going thru quite a bit of drama to run that ET (no offense either) You've run that number before too.
As I've said before,you need to work on your 60 ft.Your motor makes power,you just need to hook it. Its good you went into the motor and found the valve spring issue though.

>>The only way this could happen is if the engine dyno is underestimating the HP and the chassis dyno is over-estimating it. Also realize, they can make these dyno's say whatever they want by entering different correction factors.>>

either way its just a number, but I do feel that if I met a builder that underestimates their dyno #'s, I do think that this person would come as close as possible, like warning me the mornings numbers were going to be higher than the afternoons because of the weather..
Just a very no-frills experience from a very no-frills person. Unfortunatley I don't have a stick car, but he did tell me if I was going to do the chassis dyno thing that I might want to do it with my "loaner" converter because it will less skew the #'s than my looser one. I don't know if I will, the dyno he uses is about an hour from me, there is one closer but I don't care for how the guy operates.
I am still a little weirded out on the diagnoses on the trans, I would have much rather heard any number of things than the trans person is almost sure it had to be the converter because there was no where else in the trans for that much metal to come from.

Matt

Way more drama than I intended. Its not like I go out of my way to do this either, maybe I should find a different hobby.
I think there is a pretty good chance I could have avoided all this because I have the feeling that I would have been quick enough with a properly functioning converter to go sub 12 if I could pull off a 2.0 60' on my p315s, and I have hit 2.1's on the radials, so I figure a little technique and some luck, it might happen.

Not sure though.

matt

And I can tell you that a bad converter will cost you more E.T. and power than you can imagine. I had one of my cars on a chassis dyno with a dead converter and it lost 200 rwhp!

Good luck on yours. The right converter is super important, and not a place to save money on a car shooting for ultimate e.t.'s. Buy the best you can afford.

And again, all I was saying on the chassis dyno versus engine dyno is there's no real way to lose that small of an amount of power between the two. I've done a handful of back-to-back tests from engine to chassis dyno and the least I've seen lost is about 17%. I'm sure there are drivetrains that may lose a little less, but not 5-6%.

Good luck!

Jody

Matt,you should contact Steve Oldani and have him get you a convertor..don't give up the hobby!
..get a new convertor and get some slicks or DOT slicks and go from there.

I am going to talk with the company I got it from, I got it last year after I asked them to restall the converter I had bought from them a few years ago.
Jody, were any of the back to back dyno runs done with accessories and mufflers (in this case headers, my x pipe, midpipe, mufflers and 10" of "tailpipe")? Just a thought, I'm not really sure how much power they are worth.
I got an email from my web hosts and they said they sent me the wrong login info, I'll see if I can post the video of a dyno run (nothing too exciting) when I get some spare time tonight. I have to say I was so worried about the x-pipe sound, and I think I sort of like it actually..

Matt

Originally posted by MadMarv:
I am going to talk with the company I got it from, I got it last year after I asked them to restall the converter I had bought from them a few years ago.
Jody, were any of the back to back dyno runs done with accessories and mufflers (in this case headers, my x pipe, midpipe, mufflers and 10" of "tailpipe")? Just a thought, I'm not really sure how much power they are worth.
I got an email from my web hosts and they said they sent me the wrong login info, I'll see if I can post the video of a dyno run (nothing too exciting) when I get some spare time tonight. I have to say I was so worried about the x-pipe sound, and I think I sort of like it actually..

Matt The few I've seen were done as exact as possible; even to the point of bolting up the Cobra sidepipes on the engine dyno of one I witnessed.

The only way to get a true loss is to do the engine dyno in the same config as the it will be in the chassis. I've seen guys make 700 HP on an engine dyno and 470 in the chassis. Problem is the engine dyno was open headers, no accessories, etc. and the car had tons of accessories, smallish exhaust, etc. So it's not fair to compare at that point.

The right converter will really wake that car up!

Jody