May Prelim question/comment.. Nissan SR20DET in STU

[Hammer]

Does anyone know which SR20DET motor they are trying to get approved for STU.

[Greg Amy]

Pick your poison; you can run the Blacktop if you want. Just recognize that the TIR is going to pair down the output possibilities while you're generating a lot of heat.

Focus on maximizing torque.

[Matt93SE]

My vote would be S14 blacktop or S15.. You get a better head with the S15 engine, but you also pay a lot more. Both of them have a ball bearing T28 which will help spool and get the torque moving quicker. Plus the T25 on the red top runs out of air pretty quick. Since we're limited to stock turbos, the T25 just can't make the power needed to be competitive whether it has a restrictor or not. Well, at least not at weights attainable by the S14 chassis. (I don't see being able to get the car under ~2600lbs w/ my fat arse.)

When there's local boys putting down ~400/420 in a 2900lb Pontiac, it's going to be incredibly hard to make the SR20 competitive at 2700lbs with a 31mm restrictor that will give you roughly a max of ~300hp.

[Greg Amy]

Solstice with the LNF has to run 2820# and a 34mm restrictor, and it has to remove -2mm for RWD. That's a 32mm hole; there's no way they're putting out even close to those numbers for STU.

If you can get the S14/S15 chassis down to 2675#, then you're running a 31mm hole. 1mm down but also 135# down.

The old SR20DET would be hard-pressed to compete with the technology of the Ecotec LNF, but in general this isn't a terrible pairing. And, if someone builds one and demonstrates it, it has the opportunity to drop that -2mm.

Build it.

[Hammer]

If you were starting from scratch in building one, which chassis would you use. I am thinking of building one versus converting my ITA 240sx. I am looking at trying to find a Nissan for a national class for the runoffs at Daytona next year.

[Matt93SE]

I wouldn't start from scratch- I would buy my S14 that's for sale and drop an SR in it. replace the 8 yr old coilovers, and you'll be well on your way to a competitive car. (I bought an EP RX7 that is/was quite a bit faster for the price it would take me to put an engine and suspension into the 240SX, and EP is quite strong here with national-level competition at every single race. STU is lacking in tough competition, so it doesn't make a ton of sense to me to spend a bucket of money to make it faster with little competition to run against.)

The S14 chassis is a touch bigger and heavier, but it's also a stiffer chassis and has better geometry in the rear subframe so you can get better corner exits. With the 5-lug hubs, you also get better wheel bearings that last a lot longer than the S13.

[Hammer]

I will keep your car in mind when doing my research. Distance from Orlando will be an issue

Initial feedback from friends is the s13 hatch may be the chassis to use.