A carburator is a scientifically calibrated device designed to deliver the Wrong amount of fuel at a given moment, in anticipation of the next - David Vizard (writes alot of engine tuning books)

I thought it was a funny quote and worth the bucket of gasoline to throw on the fire

 

proof that ...

 

hahah its funny that david said that, since we are both very good friends...i need to call him ask him about this...LOL

 

nice rides have a 71mazda rx2 FI turbo and will never go back to all motor although turbo more$ its also more fun

 

If you want torque just get a V8, quit screwing around with forced induction. Turbos are for people who aren't man enough to admit they want displacement.

(did I do that right?)

 

coming in? no ... wait ... incoming ....





(did i get THAT right?)

 

a carb is about as efficient as the rotary

 

but then we fix the rotary with EFI...

 

If you want efficiency, get a carb.

If you want to be cheap and get the tuning right in the space of minutes instead of hours and many jets and gaskets and such, go EFI.

Seriously, I went EFI because I'm cheap. I miss the fuel economy though.

 

Here is some new video of my rx7 at Buttonwillow. It has a MOTEC EFI with a small BP 13B.

Buttonwillow: 6 total
http://www.vimeo.com/7074917

http://www.vimeo.com/7075241

http://www.vimeo.com/7075589

Fontana: 2 total (they are longer)
http://www.vimeo.com/5950934

http://www.vimeo.com/5950934

 

God I love that sound

 

Should sound even better next year

 

Car looks great

 

Love that car! Body is waaay coool!

Got an HP book that says "Webers go with Rotaries like Wine and Cheese."

gd

 

Budget and experience plays a big role when it comes to carb vs efi. I have soooo much history with carbs and can dial mine in to a dime with experience and my wideband. I recently bought a great 750 dp and will do the hp conversion for a total expense all in of about $300. To convert to efi, I need a standalone, have a laptop so that's okay, and need the right throttlebody, inejectors etc. So for about say $1500-$2000 I could improve my fuel economy and squeeze a couple more hp. Consider i drive my car 2-3 times a week in the spring/summer the fuel savings would cover the expense in say, 30 years.

Now a buddy did the carb conversion on a s4 n/a stockport looking to test for gains. He saw a little difference in top end but in the end the driveability and economy won the nod to return to factory efi. Mind you he wasn't tuning by a wideband and didn't have the 25+ years of carb experience i have. Nonetheless, it was a waste of time in my eyes.

For my application the carb is ideal, the raw fuel mixed with premix does wonders to lubricate my camden. When I upgrade to a turbo setup, it will have to be efi though.

 

can anyone post a dyno of a NA 12a bridgeport besides the like 1 or 2 I saw?
I'd like to see the hp and tq curves on a dyno

 

Yesterday i was on the Superflow dyno again. This time with Jenvet 50 mm throttle bodies compared to the 55 mm TWM throttle bodies i tested in January. My hope was to gain more torque and some more hp, but was i dissapointed! I lost 18 hp with the 50 mm tbs and 8 ft/lb I also had big knock and ping at 9000+ rpm with only 22L and 3 deg split. Engine has RX-8 10:0 rotors. Now my question is,could the MSD 100 ohm/ft cause crossed triggering leading and trailing and the problems with knock? Went back to 21L and split 5 degree and no knock. Have read that most BP and PP engines like 24-27 L, but not this engine Oh must mention that with 55 mm tb power was 320 hp and with 50 mm tb 302 hp but with correct fuel curve and a fuel additive to the V power 99 fuel 310 hp@9600 rpm was observed.
More testing on Monday with different exhaust headers diameters and lenghts. And the engine has a 3" HJS cathalyst and one rear silencer

/Lasse

 

What motor and porting? Is that an engine dyno or rollers?

 

^^ I'm guessing that hes using the Renesis since he said the rx8 10:0 rotors

 

for what it's worth, using Renesis rotors doesn't prove that he was using a Renesis. he alluded to it being either bridge or peripheral, which in and of itself doesn't prove anything either, but i think hints more to using Renesis rotors in an older-type 13B.

 

Better the engine breathes, less timing is needed... I´d like to know why such small split? And how went testing of new combo?

 

The motor is a 13B T2 block PP ported,with 45 mm id intake in rotorhousing. Engine was dyno measured at 300 rpm/second STP corrected hp

/Lasse

 

I was using the Renesis 10:0 cr rotors that was ceramic coated. Saw a maximum of 1580F at 9000 rpm.

/Lasse

 

Yes i think the engines that i build have hi velocity and therefore do not need so much timing. Remember that the inner dia of housing port is "only" 45 mm with a choke in the middle of intake to gain speed and velocity and ultimately good flow. This set up is for rallycross engines, but dragracing engines need a little different porting New combo on Monday did not gain any more hp unfortanately New PP engine to be testad in a few weeks

/Lasse

 

My mild half-bridge made more torque at 3200 than the street port made at peak.

Same engine, same ports except for the added eyebrow, and I switched intake manifolds because the engine actually lost power everywhere with the TII manifold.

The engine only made 175whp peak. But, it did that at 6800rpm