Defined N/a 20b semi p-port. 421rwhp
11-28-10, 10:57 AM
#51
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^ The N/A 20B is honestly just something you have to want, all for illogical reasons. Dollar for dollar, you aren't going to even come close to the LSx engine for power output. Logan and others have made incredible progress lately on this front, but as we all know 450-500whp from even an LS1 is only a cam and heads upgrade away. As you said, the sound, feel and uniqueness of the 20B is what lures the few of us in, but in racing and to be financially sane, none of that really matters.
$20k will just buy the LS7 katech engine. Are you looking to spend 20k on the engine only or the entire swap? I am sure you realize 20K will not get you close on a LS7 full swap. Not just any 20b n/a can go to 10k. There is a ton of mis-understanding in this area. The cost goes WAY up in price for a 20b that redlines at 8500 and one that can go to 10k. The price is so much higher due to these three factors- apex seals must be ceramic ($2000) New housings are needed instead of used ones for the ceramic seals ($1800) and finally a Drysump front cover/ system must be used to supply oil that high in rpm ($4000). But if you are looking to spend $20k on a engine, then the 20b n/a is way cheaper. Even one built to 10,000rpm spec just like mine. Oh, and its torque to the tire that matters, and how long that torque takes place. Horsepower and average power in the shift range is what wins. Anyone that doesn't believe that can ask themselves why in japan there is 300hp class and 500hp class. No mention of torque. Even in nasa they place you in classes based off hp/ weight. Not tq/weight. With that said, the LS7 is a fantastic engine. I say the only solution is to build both 
and then give me a ride damn-it! lol
and then give me a ride damn-it! lolI might have missed it in the thread, are you sticking with the stock 5-speed or upgrading to something stronger like a T-56? I am curious as to whether a T-56 could shift acceptably at such high RPM's.
11-28-10, 11:48 AM
#52
My $20-25k budget is engine only. Pretty much everything on the car is getting upgraded so the total will be much greater. I would be looking to go dry sump on either the n/a 20b or LS7 as I will be doing some track/auto-x duty.
I might have missed it in the thread, are you sticking with the stock 5-speed or upgrading to something stronger like a T-56? I am curious as to whether a T-56 could shift acceptably at such high RPM's.
I might have missed it in the thread, are you sticking with the stock 5-speed or upgrading to something stronger like a T-56? I am curious as to whether a T-56 could shift acceptably at such high RPM's.
For roughly $15,000 we can build you a engine pretty much identical to mine. That includes the price of the JDM 20b as well.
11-28-10, 12:13 PM
#53
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Sweet job
Just wanted to say sweet job!
Two quick questions,
Where does this rank of the NA rotary HP score board?
Do you have any pictures of how the P-port manifold mounts to the engine/lower intake manifold?
Thanks!
Once the snow melts I will head down for a few pulls with my POS.
Two quick questions,
Where does this rank of the NA rotary HP score board?
Do you have any pictures of how the P-port manifold mounts to the engine/lower intake manifold?
Thanks!
Once the snow melts I will head down for a few pulls with my POS.
11-28-10, 06:14 PM
#54
You have to understand that instant hi torque on a light weight car makes it more traction limited. The torque curve of a rotary is more progressive which helps load up the suspension to react. V8 torque however is instant so the suspension doesn't get much of a chance to adjust in time to help for traction. Howard Coleman is the one who made some of the V8 swap guys aware for this in the Fd chassis. Truthfully a 2800 lb car doesn't need that much torque to be fast. I'm currently test driving my NA 20b right now with stock wheels and tires. Even with the so called low torque of a rotary, I still spin the rear tires on a 5 mph rolling start when I floor it in 1st. Now my tires aren't the best but this is something I didn't expect to happen. I built my own intake from scratch. My primary intake runners are very long for the bottom end and I have shutter valves that keep the secondaries closed till above 3k. Would a stock intake perform like this???? I have no idea since I haven't dynoed my set-up yet. I'm very very happy with my bottom end torque right now so far. And this is comming from a guy who worships the factory twin turbos.
11-28-10, 06:24 PM
#55
^Just to add to the above, I made the trip out today to defined autoworks and spoke to Logan about plans for my car, and he was nice enough to show me around and give me a ride in his 20B FD. I will say I'm very surprised at how well it pulled even at ~4-6krpm. Even without winding it out, it was still extrmely quick and responsive. The midrange is even better than I was anticipating. Also at WOT.. well lets just say I may have pee'd just a little. Sorry about the seat Logan Haha. Seriously the car was impressive though.
Haha. Seriously the car was impressive though.
11-28-10, 06:54 PM
#57
Just wanted to say sweet job!
Two quick questions,
Where does this rank of the NA rotary HP score board?
Do you have any pictures of how the P-port manifold mounts to the engine/lower intake manifold?
Thanks!
Once the snow melts I will head down for a few pulls with my POS.
Two quick questions,
Where does this rank of the NA rotary HP score board?
Do you have any pictures of how the P-port manifold mounts to the engine/lower intake manifold?
Thanks!
Once the snow melts I will head down for a few pulls with my POS.
^Just to add to the above, I made the trip out today to defined autoworks and spoke to Logan about plans for my car, and he was nice enough to show me around and give me a ride in his 20B FD. I will say I'm very surprised at how well it pulled even at ~4-6krpm. Even without winding it out, it was still extrmely quick and responsive. The midrange is even better than I was anticipating. Also at WOT.. well lets just say I may have pee'd just a little. Sorry about the seat Logan Haha. Seriously the car was impressive though.
Haha. Seriously the car was impressive though. Thanks for the compliments, glad it was enjoyable!2420lbs. I am going to remove some more weight this winter. Most likely in the muffler area. Heck each rear tire/rim weigh 55lbs! But 315's will do that :/
Last edited by GtoRx7.; 11-28-10 at 07:00 PM. Reason: added more
11-29-10, 12:53 AM
#58
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My PP20B, Jeff Kiesels old 3 rotor- 390 RWHP- It apears that your hp keeps climbing past 8500 whereas mine flattens out after ~8000.
Ill find the spreadsheet and send it if you want.
Ill find the spreadsheet and send it if you want.
11-29-10, 03:06 AM
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Yeah pretty much no synchro tranny will like life very long when taking 10k shifts all the time. T-56 will have a hard time over 8k. I am using a G-force t-5 transmission. Which is a straight cut gear, dog ring setup. 10k and clutchless shifting is a win/win
For roughly $15,000 we can build you a engine pretty much identical to mine. That includes the price of the JDM 20b as well.
For roughly $15,000 we can build you a engine pretty much identical to mine. That includes the price of the JDM 20b as well.
$15k sounds pretty good. This thread has definitely piqued my interest!
11-29-10, 09:44 AM
#61
I am not familiar with the T-5, I will have to do some research. Is it disturbingly loud with the straight cut gears? Do you street drive the car at all? I've read dog ring setups are a no-go on the street.
$15k sounds pretty good. This thread has definitely piqued my interest!
$15k sounds pretty good. This thread has definitely piqued my interest!
11-29-10, 12:46 PM
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If I'm not mistaken, his experience (at least with this N/A version) was that the peri-port gave better torque/power throughout the entire RPM range. I'm not sure whether the same would be true for turbo application or not, this concept has crossed my mind many times.
11-29-10, 01:16 PM
#65
If I'm not mistaken, his experience (at least with this N/A version) was that the peri-port gave better torque/power throughout the entire RPM range. I'm not sure whether the same would be true for turbo application or not, this concept has crossed my mind many times.
11-29-10, 01:38 PM
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11-29-10, 11:42 PM
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Another question occured to me..
with an ITB setup, do you still retain a IAC of sorts?
can you run ITB's and retain A/C and P/S for example...
is there a way for the ITB's to compensate for the load of the A/C coming on etc?
with an ITB setup, do you still retain a IAC of sorts?
can you run ITB's and retain A/C and P/S for example...
is there a way for the ITB's to compensate for the load of the A/C coming on etc?
11-30-10, 12:04 AM
#68
It is definitely possible if someone wanted to. Electromotive and others sell a IAC that uses dual barb fittings, and can be remote mounted. With the ITB's simply "T" together into a common vacc line, the IAC could splice into the source. Personally I ran P.S with ITB's (back in the day) and the load wasn't enough to effect the engine. A/C is a different story, but most standalones have a "a/c input" which can add timing when activated. That may be enough even without a AIC.
11-30-10, 03:40 PM
#69
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Could you clarify? Is it possible to run an air conditioner system with an engine such as yours? If not, that would be a serious pitfall for me since I live in a ridiculously hot place.
03-08-11, 08:58 PM
#72
There are more videos and a newer dyno run here-
https://www.rx7club.com/build-threads-292/non-turbo-428rwhp-fd-build-up-history-937570/
I should have some even newer stuff very soon to look at
https://www.rx7club.com/build-threads-292/non-turbo-428rwhp-fd-build-up-history-937570/
I should have some even newer stuff very soon to look at
03-19-11, 07:17 PM
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"Kits" that have p-port manifold/ ITB's
Keep a eye on our Website,
we will be offering "Kits"
that have the p-port manifold/ ITB's
already attached to stock lower manifolds,
and pre-made semi p-port Housings.
This will open up a whole new world
for turbo lovers and n/a guys alike
Where?
What WebSite?
we will be offering "Kits"
that have the p-port manifold/ ITB's
already attached to stock lower manifolds,
and pre-made semi p-port Housings.
This will open up a whole new world
for turbo lovers and n/a guys alike
Where?
What WebSite?
03-20-11, 08:30 PM
#75
Our website is www.definedautoworks.com
Take a look and you will see we have the semi p-port housings listed, and the manifolds will come very soon!