SR20 with carbs?

shifty · Post by **shifty** » Tue Oct 03, 2006 2:59 pm

After going to the JCCS and seeing all the SR20-powered cars, as well as talking to folks about them, I think my next project will be to put together one of my '67.5 1600's with an SR20.

I really like the U20 in my '69, but after driving my friend's '60 TR4 with an overbored 2.2, I'd really like some grunt. His car pushes you back in the seat in every gear and sounds great - like a half-v8!

My car will cruise all day at 75-80 mph, but lacks grunt. I'll admit to being a bit nancy about putting my foot in it, but I'm afraid of that timing chain eating the engine!

A motor I can flog without worry would be really nice, but I like the look and sound of carbs. Is it nuts to try to carb an SR20?

I'm also not really a fan of turbos, I know modern ones are better, but I don't like the lag. Is there a supercharger available?

I should be looking for an S14 or S15 SR20DE with 5-speed, corrrect?

Thanks!

spriso · Post by **spriso** » Tue Oct 03, 2006 3:22 pm

Is it nuts to try to carb an SR20?

No, it is not nuts to carb an SR20, but part of the sweet thing about EFI is the fact that you will have a smooth running car, that is not too fat or to lean, and will give you the drivability of any modern car.

There is nothing better than going outside, hitting the key and having your roadster start and idle perfectly. No carbs, no cold-blood running issues, just super sweet power delivery no matter what the temperature, or altitude is.

I should be looking for an S14 or S15 SR20DE with 5-speed, corrrect?

Any of the RWD SR20DE enignes will do-- even the 140hp S13 models. Yes, you will pick up more power and have a newer engine with the S14/S15 engines though.

And remember, I sell motor mount kits as well as alternator mount kits for SR20 swaps into Datsun roadsters!

Good luck, and please don't hesitate to contact me with any questions about the SR swap into the roadster!

Michael Spreadbury
spriso.motorsports

datsun65 · Post by **datsun65** » Tue Oct 03, 2006 6:52 pm

Leigh,

You can also go KA24DE or even KA24E with carbs (Though I prefer the EFI).

Check out Dan Gallmeister's built KA24E engine with carbs (btw a few months ago he was looking to sell...don't know if he sold it, or not)

datsunfreak · Post by **datsunfreak** » Tue Oct 03, 2006 7:21 pm

shifty wrote:A motor I can flog without worry would be really nice, but I like the look and sound of carbs. Is it nuts to try to carb an SR20?

I don't think so.

FYI, I can get you what you need if you are serious about doing it.

datsunfreak · Post by **datsunfreak** » Tue Oct 03, 2006 7:22 pm

FYI, those aren't carbs. That's EFI...

datsun65 wrote:Check out Dan Gallmeister's built KA24E engine with carbs (btw a few months ago he was looking to sell...don't know if he sold it, or not)

shifty · Post by **shifty** » Tue Oct 03, 2006 7:28 pm

Nice! There is something that really appeals to me about popping the hood and seeing some big, honking carbs.

I saw a picture years ago of a 1.6 Miata running SU's.

Are those Webers or Mikunis?

datsunfreak · Post by **datsunfreak** » Tue Oct 03, 2006 7:33 pm

shifty wrote:Nice! There is something that really appeals to me about popping the hood and seeing some big, honking carbs.

They sound pretty mean too.

shifty wrote:Are those Webers or Mikunis?

Mikuni 44s.

Pretty much everything in that photo is for sale if you're interested. You could have the first running carb'd SR in the US.

datsun65 · Post by **datsun65** » Tue Oct 03, 2006 8:59 pm

urg

I shoulda paid attention

Crazy Backyard Builder · Thu Oct 05, 2006 2:23 am

Leigh,

You should hear what a NA SR20de sounds like, sounds great sort of like a set of carb's. It all depend's on the way the intake piping is made.

Besides once you go to the work to put an SR in you might as well run the injection that comes with it. Carb's are getting pretty expensive nowaday's, plus the price of a manifold. Never mind the tuning time and finding someone with a supply of jet's. The injection is a more cost effective route.

Just my 2 cents,

CBB

datsunfreak · Post by **datsunfreak** » Thu Oct 05, 2006 6:46 pm

Crazy Backyard Builder wrote: Carb's are getting pretty expensive nowaday's, plus the price of a manifold.

Well, I'm selling a pair of rebuilt carbs and the manifold for about what a set of carbs goes for on ebay.

datsunfreak · Post by **datsunfreak** » Thu Oct 05, 2006 9:23 pm

FYI, carb'd SR is sold. I'll leave it to he who bought it to crow about it.

shifty · Post by **shifty** » Thu Oct 05, 2006 11:39 pm

Yep, I bought John's engine! So I guess I'll find out how well it works (and sounds!) and whether it is nuts.

I suppose I can go back to injection if need be.

But I do get a perverse sort of pleasure out of pulling the "starter circuit" knob (remember with Mikunis it is not a choke) on the U20, turning the key and hearing that big sucking sound.

GoldHawg · Post by **GoldHawg** » Fri Oct 06, 2006 3:10 pm

anybody know where there are pics of the frame cuts that need to be made for the SR20DE? I would love to see how much cutting is involved, and what strengthening needs to occur around those spots.

Thx!

Seth W · Post by **Seth W** » Mon Nov 06, 2006 6:32 pm

their is a preaty good how to on the 240 forums about doing those on a KA http://240sxforums.com/forums/showthread.php?t=58363 you'll have to register though. basically you use 01' or higher Suzuki GSXR 1000 or 750 Throttle Bodies

TurboRagtop · Post by **TurboRagtop** » Mon Nov 06, 2006 8:11 pm

OK, call me a carb Nazi, but having run both carbs and now EFI in my roadster, I would never go back to the carbs. Not even for money.
Remember what the auto industry learned about EFI; when they eliminated the carbs, suddenly the warranty claims for upper cylinder problems (rings) and prematurely worn bearings dropped like a stone. WTH? they asked themselves, (scratching their skinny bald heads) then research showed that the cold starts, accelerator pump events, etc. that come with carbs tended to wash the oil out of the upper cylinder/ring pack and contaminated the oil with gasoline, such that if you weren't RELIGIOUS about oil changes, well... your engine would be all done by 80K - 100K.
With EFI, the high-mileage durability almost doubled. Warranty claims went to the basement.
This is not my opinion, it is empirical data, not predictions.

Something to think about. */end anti-carb rant/* LOL

Datsun Roadster Forum-311s.org

SR20 with carbs?

SR20 with carbs?

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