Datsun Roadster Forum-311s.org

I have been kicking the can for a long time to do a SR20DET swap on my 66 Roadster, or to use the parts I have (5 main block, U20 Rods and Pistons, Cast iron 1600 head, U20 5 speed) to build a R20. I would need all the intake stuff still for the R20. SO I am wondering if anybody has kept track of the cost to do just the basic SR swap with nothing fancy extra... if that is possible.

I did a cost analysis and it was cheaper than I would have guessed for a NA SR20DE. Its still in the $10K+ range to have it done. IIRC its about 50/50 labor/parts.

I would suggest going with the R20.

Shant performed his NA S14 SR20DE swap for under $5k:
http://www.311s.org/phpBB3/viewtopic.ph ... t&start=15

Figure $1800-$2500 depending on SR20DET variant + plumbing

Alvin wrote:Shant performed his NA S14 SR20DE swap for under $5k:

50% of $10K sounds about right for the parts for a NA conversion........

If you have to pay someone to do it, it can add up quickly. But if you have basic fabrication skills, and like to tinker, then they can be done for 5-8K depending on what you want to do.

There is lots of good write ups in the Engine Swap section on this site-- including a tutorial that I wrote that should help you along the way.

If you need conversion parts, we carry it all! http://www.spriso.com

Michael

For the R20 I would suggest you use your R16 rods and custom pistons. Lose the excess weight. 200 - 300 grams per cylinder will make a noticeable difference in acceleration, less noise/vibration, choose your compression ratio (suggest 9.5-9.7:1 for pump gas), skirt coatings...NOT a big dollar item!!

First, consider if you are doing DE or DET.. Massively different fabrication problem. Huge difference in complexity.

There are a lot of little things that need to be dealt with to do it right. They all add up.

We always say at the shop "...SR20DETs are twice the work, twice the cost, but twice the fun..."

-m

Thanks all! If I did the swap, it would definitely be a DET. Other than specialty coatings, I would be doing all of the work my self. I have all of the tools and skills to get almost all of the work done. The ironic problem I face with the SR20DET swap is I Know i will be after more power since I know the engine is capable, but then I would be looking at a RX-7 GSL-SE or custom ford 8" rear for strength and obtainable LSD. I also love the Idea of a stock'ish looking R20. I have been a slow car fast guy for a long time (Air cooled VWs).

If you are a slow car fast kind of person, consider if you really need all that power.. This is with 200ish HP against a 500hp Subaru and a well driven Ferrari..

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Pretty good for 200 hp for sure. Looks like another 75-100 hp would have brought you around those cars in time.

I started assembling all my DET swap items last January such as Spriso mounts, Big brake kit, Rotors, alum-Calipers, stainless exhaust pipes/flanges and V-band clamps. Picked up a low mile engine and had it fully forged internally and the head port matched etc. Tomei cam set and metal head gasket.
I'm still looking for the RX tranny though. ( Anyone know of a unit in SOCAL ?)

I'll be doing all the frame fab etc and will try to keep a tab on costs .

Another 100hp would be nearly undrivable on track.. We can only really fit a 205 tire under the fenders and drive it hard unless you make pretty extensive body mods.. Its wildly fun and exciting to put mid 300s hp through a 205.. In a straight line you are sliding.. Corners become something you avoid, which is a sad thing with as much fun as it is to really drive these cars..

I could have passed that Subaru the first lap. But without a full cage and suit and all, I am not willing to stuff the car into corners underneath people without some acknowledgement that I am coming.. I waited until it was clear he was not going to give me a point by, then I pulled out in front of him and blocked down the straight.. The reality is another hundred horse was not going to deal with that car. It was just too fast in a straight line..

All that said, if the plan is to go embarrass Porsches on PCH.. go for about 350.. And hold on.. I suggest a strong steering wheel and a radar detector..

I would start with making the car handle and stop. Shocks, bigger brakes, vented rotors, light weight wheels, not just plain old alloys, 3 or 4 link rear suspension, composite leaf spring or double adjustable coil overs, watts link, sticky tires and put the rest back to spec.

My friend Steve, who has worked with racers and enthusiasts developing engines etc for years, has always talked about "balance" when it comes to power, and has warned about over powering the car or throwing the weight off such that it is no longer as much fun to drive. I think RCMike states that well.

RCMike wrote:All that said, if the plan is to go embarrass Porsches on PCH.. go for about 350.. And hold on.. I suggest a strong steering wheel and a radar detector..

Well said Mike but we must not underestimate the thrill factor involved in spanking the midlife Mustang and Corvette crowd too!

Jon