i've set up a blow through system on a L20 running twin 40DCOE webbers on it and it works really well. All you need to do is run a rising rate fuel pressure regulator and run a blow-off valve before the carbi's also you'll need to run a good fuel pump ( I run a holley Blue ) The pump has to run 4-5 psi more than the boost your running. This set-up work's really really well.

For the cost of the rising rate fuel reg, the holley pump and the BOV I could build the whole drawthrough set up.

suck through or draw through will always be the cheapest, and give good value fo $$$ but has the most power limitations.
good for cheap power though

Thats the crux of the problem, most so called "Professionals" can't even set up a blowthrough carb properly, let alone tune it, and the costs aren't much shy of EFI.

Basically run either suck though for a couple of hunderd or EFI for a couple of thousand.

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I agree! Stuff in a big cam and have some fun. If drawthrough cant give you enough grunt, put it on the sqeeze. You might get a surprise how well it goes.

I set mine up at home and the fuel pump was second-hand for $80.00. The fuel pressure regulator is a holley blue modefied for $40.00 and I made up an aluminium plenum chamber for around $180.00 and bolted it straight on to the webbers, retarded the timing and went from a 15.6 at 75mph to a 13.9 at 96mph. Didn't have to tune the webbers at all.

I set mine up at home and the fuel pump was second-hand for $80.00. The fuel pressure regulator is a holley blue modefied for $40.00 and I made up an aluminium plenum chamber for around $180.00 and bolted it straight on to the webbers, retarded the timing and went from a 15.6 at 75mph to a 13.9 at 96mph. Didn't have to tune the webbers at all.

Thanks guys, I appreciate all of your help.
This SU syle carburetor, does it come stock on Datsuns, because mine just has the one barrell. Can you give me the exact numbers and stuff so I can maybe find one? Also, what type of needle adjustments do you do to the SU?

Also, Roddat, did you just blow through the webers without a box around them? I was just assuming you did.

If you guys could give me some detail about your carburetor setups for both draw through and suck through, I would appreciate it. bwp475s@smsu.edu

Not that I am ignoring the fuel injection guys, but I just want to have a little fun for a little cheaper, being a poor college student and all.

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One barrell?
I have never known of an "A" series Datsun passenger car engine to to be factory fitted with a single "one barrell" carb. GX's came with two "one barrell" carbs.
Can you read the make & model number on the carb? This has me intrigued.

Maybe it is not a one barrell. It looks like the one in the section "which carburetor?"
It looks just like the stock Hitachi 306. I thought this was a one barrell, but I guess I could be wrong. I was reading about it in the "which carburetor" section, and is it an SU style? What did the 1 3/4" SU come on? Sorry, I am just confused.