Reseda Dyno Day - Results

[RoninLB]

Originally posted by dd74
Ron: are those horsepower figures (210/154; 230/172) for the 2.7?

[DIN] HP/kW 210/154 2.7 Carrera

[SAE] HP/kw 230/172 2.7 Carrera

[rdane]

Originally posted by turbo6bar
Dane, in looking at the dyno graphs for the 3.0s, I noticed your engine does not make good torque until 4000 rpm, but it holds great to 5500+, while the stock engine's torque drops off quickly, but also builds torque a little sooner. Did you 20/21 cams cause a loss in driveability at lower rpms, or do you always keep rpms above 3000-3500 anyway.

I printed the graphs Jurgen and it looks like the torgue numbers start pretty much at the same place. I am 135 @ 3K while the other runs are 2 @ 145 and 1 run at 155 @ 3Krpm. (we need more numbers) Not sure what 10 ft/lb of torgue is really like Tom's torgue zooms out of spec for an SC's numbers I think. But as Superman says about his 20/21s the cam is much more driveable around town. I wholeheartly agree. I pull rollings stops now in 2nd and easily drive 2nd around town. Not as easy or as fun with the original cam. 1st zooms to redline as does 2nd and so on. I know between 4 and 6K I really have fun with the riciers on the freeway. I have 190K miles on my engine (and the oil consumption that goes with it) with the original P&C so that maybe why my torgue #s are down. I'll show the data when i change the P&Cs out. But it won't be the same size or compression P&Cs so it isn't much help.

Looking at the graphs, Porsche HP is NOT cheap.

No kidding! But a cam, exhaust and muffler did get me to 215 @ the crank.

If Webers will add 20-25HP to a 3.0, will custom EFI also give the same?

I keep seeing high numbers on the Webers. I suspect it will be more like 10/15 unless you go to a pretty radical cam and piston set.

Looks like Wayne can set us up on the PMO carbs so I'll let you know how that turns out.

cheers,
Dane

[dean]

Originally posted by rdane
I would like to see a bunch more dynos on 3.0s though.

[Langers]

Originally posted by jluetjen
Did you notice that the torque curve for both the MFI and the DME engine dipped when the air-fuel mixture made a sudden dip. I wonder if these represent opportunities for improving the torque of the engine?

I noticed that too.....very interesting.....very noticable on Tyson's car but then again that is MFI and it's very hard to get the space cam 100% correct.

[KTL]

I love Dean's post.

A dyno chart and nothing else. Nothing else needs to be said. 320-something HP............ NICE!

You want HP? Force feed your motor with a well designed turbo system. Not cheap, but effective and efficient.

[ValveFloat]

Damn Dean, that thing needs some fuel. Seems pretty lean for boost and that kind of power.

[dean]

You are correct sir. It is lean. I am not driving it until I do the EFI thing. And that is coming up soon. Woo-hoo.

[mjshira]

Jack, What year is your 3.6? What a great result! Especially considering you have not had that engine apart!

[Bill Verburg]

The most usefull aspect of the day is the comparison between the 3 different setups. As I have posted before comparison #s from different dynos on different days w/ different normalizing routines are IMHO almost useless. Here you can compare back to back runs which will show the comparative strengths of the different engine/ chassis combos and the relative ability of the chip to add hp, Though it is troubling to see that different gears were used(perhaps i misread that part?), the mathematical renormalization of the results obtained in different gears w/ different tire heights is one of the many possible sources of error. It would have been nice if the scale of the different runs was the same so that a visual comparison of the 3.6 vs the others was possible.

I am certainly looking forward to trying one of Z/S or is it S/Z chips myself. Nice job guys!

[dean]

Originally posted by KTL
I love Dean's post.

A dyno chart and nothing else. Nothing else needs to be said. 320-something HP............ NICE!

You want HP? Force feed your motor with a well designed turbo system. Not cheap, but effective and efficient.

Kevin,

Thanks

Bill,

I was wondering about the different gears also. I thought one should use as close to a 1:1 ratio as possible. In most cases 4th gear.

[Tyson Schmidt]

Bill, we each tried two different gears, then on the third run, chose the gear that gave the best results. David and I both have the same ring and pinion, and the same ratios. Jack has an 8/31 ring and pinion and close-ratio gears, so it is tough to find a similar gear.

What makes the most sense is to find you own best gear, and go with that one. After all, the only horsepower number that matters is the one that that shows what actually gets to the ground. What would be nice though, is if we were actually able to calculate parasitic loss.

[Bill Verburg]

My point exactly, any difference in gearing, whether from gear selection , axle ratio or tire height will affect the #s.

Theoretically for a comparison to another car to be validly made all of the #s need to be massaged, the technical term is renormalization to a baseline condition. Other variables are the usual atmospheric STP.

It should be obvious that the best #s will come from the lower gears. There will be discrepancies because of the variable grip/slip between the tires and rollers, that is why the Dynapack is preferred because it eliminates that varible.

Along those lines Dean's post is relevant, 4 ^th is the preferred gear for most chassis dyno runs because it is 1:1 in most 911s, thus eliminating another potential variable in the evaluation process. If any other gear is used, it, along w/ the final drive ratio and tire height need to be included in a renormaliztion procedure for a meaning ful comparison.

[Schrup]

Originally posted by bigchillcar

Would the use of a Euro 2.7 or SC fuel distributor and porting the heads improve anything or just reduce my available cash? Ryan

I've been thinking along these lines, a track guy suggested that after I pass my last smog test next year, & after I back date my exhaust I can find some additional gains if I went with a Euro distributor & injectors. Any thought, don't really want to get into internals unless I have to, mainly looking for bolt on HP for now. Any thoughts. TIA

[RoninLB]

Originally posted by pschrup
Any thought, don't really want to get into internals unless I have to, mainly looking for bolt on HP for now. Any thoughts. TIA

I'm only a fly on the wall on this thread. But

I think the non-O2 '78-'79 CIS, the '78-'79 intakes, and proper ignition advance may give you 200hp in your '80 with it's high compression ratio, instead of the present 180hp

[rdane]

I passed Washington emissions with my '79 this year and the SSIs in place. That is the most cost effective update for HP on an SC.

You'd be hard pressed to pickup 20 HP elsewhere.

[emcon5]

Originally posted by pschrup
I I can find some additional gains if I went with a Euro distributor & injectors.

Injectors for all SC engines have the same part number.

All 78-79 SC fuel distributors (engine types 930 03/04/05/06/09/13/15/19) have the same part number. (911.110.225.01)

The late euro (type 930.10 204HP) SC has a different number (911.110.977.00) than CIS.Lamda US/Japan models (type 930.07/08/16/17, p/n 911.110.971.00), but is not directly compatable with CIS w/ Lamda systems, there is an extra fuel line from the frequency valve, which ROW cars did not have.

It is also worth noting that the 204 HP ROW 930.10 had the same small intake ports as the 180HP us model engines.

Tom

[911pcars]

In regards to the simple addition of SSI heat exchangers:
"You'd be hard pressed to pickup 20 HP elsewhere."

IMO, I don't think one can conclude this much HP advantage using SSIs alone. It'd be difficult to A-B compare early and late vs SSI heat exchanger systems on a same day dyno test, although I'd like to see one.

Sherwood

[rdane]

Sherwood I agree. I should have left the comment that SSIs are the most HP improvement for the $. I doubt any one addition will get you 20 HP on a SC. Although I keep getting told Carbs will give you 20/25 hp alone.

[dd74]

SSIs are one thing, what I would like to try out are actual race headers; maybe in the realm of Bursch headers.

1) As Tyson and I discussed, SSIs will provide some gain over stock pre '75 heat exchangers because the SSIs are true equal length, while the OEM h/es are "almost" equal length.

2) Headers, despite their lack of heat (and potential weight savings because of the missing heat "shroud") might provide additional gain to the SSIs as they come in different sizes for 2.7s and 3.0s.

[dd74]

Also I need to post an addendum to Jack's initial post:

1) My car is equipped with a Triad dual-in-dual-out muffler - not a Monty muffler - along with '74 OEM heat exchangers

2) Oh, and my last name is spelled "on," not "an." (French-Canadian by descent - not Armenian as would be the case with "an.") Everyone gets this wrong, however.

Lastly, if tire size is of any issue, the tests were run with recently installed 205-50-15 Yokohama EVS 100 tires on 15x7-inch rims front and back.

Thanks.