Weber 38 dgev jetting

[Dirttrack510]

As most of u know I race a datsun 510 wagon on a dirt track(new season starts this weekend). I'm running a L16 with flat tops. Has anyone else ran a similar setup and has a idea where to start with jets on my 38dgev weber? I just don't want to buy a ton of extra jets i'll never use.

Any info on a starting point would be great.

[erichwaslike]

i can get back to you on this, we just did my dads 521 w l16 and checked my 521 w l16

[racerx]

have you got a hold Pierce Manifold in Morgan Hill..theys hould know what jetting.

[Dirttrack510]

Ok, i'll check that out

[banzai510(hainz)]

I had one and just bolted it up and ran great.

However it was over jetted(came of a Land cruiser FJ40)  the intake manifold got black inside and I could see the valve had buildup on the back of the valve in 40k miles.

 

never opened it up to get a jet # reading

[Dirttrack510]

Mine runs pretty good, but it bogs a little when I floor it. I called pierce and they have jet numbers.

[banzai510(hainz)]

but it bogs a little when I floor it.

 

Unfortunatly I think thets the way it is as a SU set up the slides keep the is OVERLY bogging out as it keeps the air vol higher. as RPMs go up the better. SUs dont have accel pumps either.

On the mechanical 38/38 if you open up to fast you equilize the pressure and NO GO.

You have to learn how to use it to get the top performance.But it does have a accel pump.

 

I always had troubles on hills trying to cluth it just right or it would have no power/kill it. Once off ilde it was fine. But in a high gear and slamming on the Gas isnt going to help.

[racerx]

Many moons ago, I had opportunity to run 38 on my Datsun 510 cuz knew someone with Toyota ol school Celica selling one but I think it's just too much gas for Datsun 510s.  This was confirmed by Pierce manifold awhile back.  Even for old school Celicas, had a 75, which is a 2.2 (20r)...only needed a 32/36 weber.  Bigger carb does not really give you more HP...

[Dirttrack510]

Keep in mind this is a full on race motor with 11:1 compression 572 lift , big valves, header, full port and polished head, matched port manifold, etc... I started with a 32/36 and it wasn't flowing enough air and fuel and was cutting out around 6500 rpm. With the 38/38 I can turn just under 8000 rpms. I'm just looking for a little more throttle response. Pierce said the 38 weber should be just right for this engine, I just have a lot of carb mods to do to get it perfect. :)

[racerx]

Keep in mind this is a full on race motor with 11:1 compression 572 lift , big valves, header, full port and polished head, matched port manifold, etc... I started with a 32/36 and it wasn't flowing enough air and fuel and was cutting out around 6500 rpm. With the 38/38 I can turn just under 8000 rpms. I'm just looking for a little more throttle response. Pierce said the 38 weber should be just right for this engine, I just have a lot of carb mods to do to get it perfect. :)

That was not described earlier but if that's the case then a 38 may be for you.

[Dirttrack510]

 

That was not described earlier but if that's the case then a 38 may be for you.

Sorry, my bad. I just wrote full race motor. Anywho... Only 2 more days till race session :)

[racerx]

Sorry, my bad. I just wrote full race motor. Anywho... Only 2 more days till race session :)

Good luck and have fun..BTW how much HP do you think/know your engine is making?