Whats the new hot engine combo for rx7

[Exidous]

My primary motivation was that I was finding full used LS7 rotating assemblies for ~$1000-1200. Leaving only the block. I have not looked in the last year or so and aftermarket may be the only option now.

A 416 doesn't allow you to have an RX-7.0 :-) I've also seen a few dyno results on the tech that seemed a bit underwhelming.

[atli126]

A ls3 would be a dream and plenty for me

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[largeorangefont]

A ls3 would be a dream and plenty for me

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You can easily make LS3 level power with a lightly modded 5.3-6.0 Cathedral port setup.

[largeorangefont]

My primary motivation was that I was finding full used LS7 rotating assemblies for ~$1000-1200. Leaving only the block. I have not looked in the last year or so and aftermarket may be the only option now.

A 416 doesn't allow you to have an RX-7.0 :-) I've also seen a few dyno results on the tech that seemed a bit underwhelming.

A LS3 based 416 with any mild cam is going to make more power than a stock LS7.. period. I don't know what would be underwhelming. The LS7 is a great engine, but is not magical.

The stock LS3 with an ASA cam makes 525 HP. My 5.7 stockish LS1 will with stock heads and the same ASA cam is marking around 470 HP.

[ZDan]

A 416 doesn't allow you to have an RX-7.0 :-) I've also seen a few dyno results on the tech that seemed a bit underwhelming.

IMO "RX-6.9" is a modestly decent joke...  But I'm 6.8...
Anyway there's nothing magical about the 11 cubic inches between 416 and 427.  All else equal (same cam/heads/intake/exhaust/etc.), 427 will make 2.5% more torque in the low-end/midrange, and between 0% and 2.5% more power up top, depending.   If anything, swapping a 427 bottom end into setup that was "underwhelming" with 416 cubes will be even less impressive as far as hp/liter.

[atli126]

A ls3 would be a dream and plenty for me

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You can easily make LS3 level power with a lightly modded 5.3-6.0 Cathedral port setup.

I found this. Pretty wild on a 5.3 or bored out to 6.0

http://www.trucktrend.com/how-to/engine/1208tr-5-3l-bow-tie-builds-mild-to-wild/

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I assume my 5.3 with the 225/225 cam, h/i/e  somewhere around 400 crank... My car dynod 330 at lsfest a few years ago

[kinger]

Wanted to bump a 2 year old thread just for fun!  To recap lots of 'destroking' talk to get higher revs, followed by lots of ITB set ups as a dream motor. 

So going into 2020 - Whats the new hot motor? 

I'm currently looking at 4.125+ bore motor with a 4" crank, and heads with a lot of flow at low valve lift numbers (<.300) to really maximize TQ in a NA application. 

Also loving the idea of a LSA blower on my current forged motor.  Sell the FAST and large TB and have $1K into it seems like a deal any gear head would love.  Used to hate the hood mod idea but now maybe I just leave it off and paint the ZR1 lid black LOL.   

The car with NT01s bites so hard with my dainty 460WTQ my TC doesn't even kick in.  Feels like it needs more even though my face is melting as I surge to 100 in a blink of a gear change.  God these are fun cars! 

[largeorangefont]

I have a complete LSA blower minus the lid if you are interested.

But to be honest, more low end power is probably not what you really need unless you want to go widebody with bigger tires. Once you start spinning the NT01s you can go to drag radials, but those affect the handling of the car. From there you don't have a lot of choices as your traction control cripples the power of the car.

Much more than 500/500 to the tire these cars start becoming un-driveable and/or the compromises you have to make to drive them makes you not want to drive them.

Put a 50-100 shot on it and run it

[gnx7]

The LSA blower and related parts will add around 100lbs to the front end.... they also heat soak very quickly and take a LONG time to cool off.... if you are going to do it... go turbo and you can have boost by gear/time and no heat soaking issues.

Resleeved alum 5.3 from Texas Speed to 4.155 bore or bigger (4.185) with a 4" stroke running the best heads you can afford would be a hot n/a motor.  Or just buy my 441ci setup with AllPro heads/intake and make 800hp n/a with a streetable road race cam.  https://ls1tech.com/forums/market/1915086

If you need crank/rods I sell Molnar parts and they are made from a better grade steel than Eagle, K1, Compstar, Lunati Voodoo cranks that are also forged overseas.  The Molnar parts are finish machined in the USA and Tom rates them at 1500hp and less.  My machinist has been VERY impressed with their quality and tolerances.

[SOB Racing]

No offence to anyone, but I'm sick of seeing LS swaps.   They are in everything these day.   Don't get me wrong, Solid tech, bullet proof and cheap cores.

I've been looking at the VW/Audi 07k 5 cylinders to replace the 4g63 Turbo in mine.   Put a big turbo on it and be different.

Just stating to stimulate conversation...

[atli126]

After selling my fc. I miss the hell out of my lsx setup now that I have my boosted miata.

Im thinking of buying a 15+ LS3 Camaro

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[paul_3rdgen]

The K series honda motors seems to be interesting as well.  2.5L 4 cylinder turbo charged,  light weight, and packing enough horsepower to make it a fun track car.

[digitalsolo]

I kinda wanna put a Honda K series in RWD form in a little Triumph or MG.   Something that weights 1600 lbs and has 300 RWHP would be a ton of fun.

For an RX7, I can't see anything better than an LS3 with nice heads right now.   Spin it 7500 RPM and put a Magnum behind it.   For a fun car, forced induction has no purpose unless you like dicking around with stuff.   And this is from a guy that turbocharges everything he owns.

[paul_3rdgen]

I’ve been looking into the option.  Lol.  K series making 600rwhp.... fast, light and turbo charged noises.  Lol.  Only issue is that your kind of pushing your luck, back to having a high strung motor that could fail. 


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[cool]

After selling my fc. I miss the hell out of my lsx setup now that I have my boosted miata.

Im thinking of buying a 15+ LS3 Camaro

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That is exactly what I did.  I picked up a 15' 1LE just over a year ago.