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Old 12-19-2008, 10:41 PM
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BayAreaEngineer
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Default Stroker tech

I sold my 90 in 03 via Devek...they did alot of work and had customers looking for cars. Regret having sold the baby, but had to crunch hard in a new job and it was taking up space and my wife had to park outside. Have not been on renlist for years....hope it a bit calmer nowadays.

So I am back looking for a nice 5sp to modify. Want an all motor options and want 400 rear wheel hp. Lots of owners and greg B all building strokers that make about 360-380 rwhp with stock components, but what I want to know is how did devek build the 400hp+ strokers. All the 400+ strokers used devek build long blocks and motors and all stock components. Even louie otts motor was built by devek.

What did they do that was so special?
does anyone know?

What is a lightweight lifter....are'nt they all the same?
Old 12-19-2008, 11:11 PM
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ShawnSmith
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The easy path to huge HP is from the Supercharger crowd - a couple of good sources including the lunatics somewhere out there near Green Bay, and some out west here. For vastly less money than a stroker, you can have 400, or even 500 rwhp and suprisingly good reliability.

As for what's going into the strokers, it's tons of really expensive pieces - far more than just a longer crank (which ain't cheap by itself).

Lighter valvetrain components such as lifters, valves, springs, etc allow the motor to operate at higher rpm, and give you more top end hp if you build the rest of the motor to match. I did not specifically need the lighter lifters on my car, but chose to go with them since they were available cheaper than the stock OEM porsche parts which were quite expensive.

Depending on the level of tune and your need to adhere to smog requirements, you can probably produce anywhere from 380 rwhp to well into the 400's. Cubic dollars and ability to not care about fuel/smog/noise/civility/reliability are all it takes.

We are dying to see how the dyno runs on my car go. I'm running through a slushbox, and I still hope for around 400 rwhp despite keeping stock intake, manifold, and street legal cats in the mix. Previous cars from GB already hit 400 rwhp through a slushbox, and he's been learning new tricks since that time.

I suspect if you have the money to order the full works from Greg's buffet, tie it to a stickshift, and allow yourself huge open intakes and exhaust, you can easily get above 400 rwhp. Your next question will be if you can manage to get the 450+ ft-lbs of torque to do more than spin the wheels in the first two gears.

I'm not shooting for absolute-top hp because I expect to be limited by traction, not top end hp.
Old 12-19-2008, 11:38 PM
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The top "dyno" engine Doc Brown makes is about 518whp....both Anderon and Fans engines are near this with stock brains, but the high flow CF intake.... Of course Tim Dey's Devek built stroker is about 515whp using a stock intake and stock brains...Louies is a pretty similar to Tims, being built by Devek but with stand alone brains controlling the ITB 50mm intake of Louies design.....to the best I know there is not a 928 motor out there that makes more HP than Louies right now (NA motors) His best run is 584whp....not bad for a street gas 6.5L...

By far the most interesting work lately in 928 engines is done locally to the bay area....Jim Morton and Dennis Kao have achieved some excellent results in Dennis 5.0L currently at 387whp....by far the highest dyno 5.0 NA motor around...& its got stock internals, other than modified cams....He did use the lightweight lifter in his motor, so that plus cams and a slight head shave all contribute to the excellent results...& his motor passed smog too!!!
Old 12-20-2008, 12:25 AM
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GregBBRD
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Horsepower is a funny thing. I can make my Mustang dyno read just about whatever I want it to read...you name it and I can make it happen....so I'm kind of dubious about some of the "silly" claims made out there. I can "tweak" the results so much, that I tend not to even quote numbers, unless they come from the same local Dynojet that we all use...around here....with the exact same calibration, each time. Kind of one of those "independent tests"...if you know what I mean. Now if everyone gathered at the same dyno on the same day...and did the same test....we might have some real data. Otherwise, I just consider it to be a bunch of bench racing, of little value. The other technique we use is pretty simple....bring it on by and we'll run one of ours against it....that pretty much always tell the real story. I think Rob can tell a story or two about running his 380hp stroker against 500hp supercharged things....and it's not a story that the supercharged guys like, very much.

And the really nice thing is that they just run and run. I've got one running around our area that has 27,000 miles on it now....as a primary car for an attorney....who drives a whole bunch...and he has only let us change the oil once! Still has the same spark plugs that we assembled it with...along with all the other pieces. Haven't touched it, except for the oil and the filter.

I've been really heavy into the design/construction of a new intake system for the later engines, for the last 4 months. It will be ready to "test" 1st of the year. That will "open" up the bottleneck on these engines (hopefully). There's one thing I do know after 4 months....Porsche did a pretty damn good job building a intake system that fit in the given area and did what they needed it to do....it's not a simple thing to improve on!
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Old 12-20-2008, 01:36 AM
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Charley B
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Originally Posted by GregBBRD
And the really nice thing is that they just run and run. I've got one running around our area that has 27,000 miles on it now....as a primary car for an attorney....who drives a whole bunch...and he has only let us change the oil once! Still has the same spark plugs that we assembled it with...along with all the other pieces. Haven't touched it, except for the oil and the filter.
So he puts out the bucks for a stroker and only changes the oil once in 27,000 miles?

I guess I'm a real ***** when it comes to oil change intervals.
Old 12-20-2008, 02:02 AM
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one might assume that there's been an oil change once in 27k miles, probably around 15k...

or we could make less rational assumptions.
Old 12-20-2008, 02:45 AM
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Originally Posted by ShawnSmith
one might assume that there's been an oil change once in 27k miles, probably around 15k...

or we could make less rational assumptions.
Less rational. However, some of today's oils are very good.
Old 12-20-2008, 02:51 AM
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Charley B
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With a new built engine, what would be the longest you should run before replacing the original (breaking in) oil?
Old 12-20-2008, 03:52 AM
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I think my experience is pretty typical of most strokers with little mods on the top end. I think a modified cam like Dennis would easily put the engine over the 400rwhp range. as it is now, i estimate it near 385 (seems like it is stronger now that the fuel ratio is a little leaner). I wont know for sure until we hit the dyno again to get the fuel ratios right. (really fat after our last dyno run ).
The lifters are not going to do anything, as its all going to come from the little cam mod on a 85 cam, and intake work. Certainly heads will do a lot too, as most of the devek strokers had the bigger valve heads. IN fact, their engine had near 380rwhp with the big valve heads and gt cams, so it didnt get in the 420rwhp until some other tuning changes were done.

mk
Old 12-20-2008, 04:12 AM
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Originally Posted by Charley B
With a new built engine, what would be the longest you should run before replacing the original (breaking in) oil?
1000 miles. That did happen, in all fairness.
Old 12-20-2008, 04:19 AM
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And the shortest??

mk

Originally Posted by GregBBRD
1000 miles. That did happen, in all fairness.
Old 12-20-2008, 05:33 AM
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RyanPerrella
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Originally Posted by GregBBRD
Less rational. However, some of today's oils are very good.
i would love to ask a ton of questions about strokers Greg, but since you mentioned oil, may i just simply ask what brand you prefer or recommend for your engines, and for those of us still stuck with a measly 5.0L?
Old 12-20-2008, 06:03 AM
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There are cars in Europe with recommended oil change intervals of 30k kms - that's almost 20k miles. Strangely, they neither use Amsoil (sorry, Mark, had to say this ) nor do they fail frequently.

Jiffy Lube would not survive in that environment... one may wonder, what type of (crappy?) oil they use that must be replaced after 3k miles.
Old 12-20-2008, 09:53 AM
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I change the oil at a rate of 1 quart every 500 miles in my GTS......

But a stroker this way comes.
Old 12-20-2008, 12:12 PM
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Originally Posted by GregBBRD
.....
I've been really heavy into the design/construction of a new intake system for the later engines, for the last 4 months. It will be ready to "test" 1st of the year. That will "open" up the bottleneck on these engines (hopefully). .....
Is this intake something that a 5 liter supercharged engine would benefit from and if things turn out as you hope will it be made available for purchase to the public?


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