That is a lot of carb data for all those fuels.I guess you don't want to leave the lid open on any of those fuels for very long.

Andy, did you back to back c16 vs Q16?

At around that power level I've seen about 35hp myself.

Yes, we did back to back X16 to Q16 and picked up almost 30 hp. It takes a little bit of carb work to switch between fuels. BLP set me up with a carb that will switch between 2 circuit for race gas and then 3 circuit for Q16.

I also pulled a little bit of timing out of the motor and that improved things. With less timing the wide bands went leaner and the motor picked up some power. I think I might have had too much timing in it before which might be why the heads got hurt last time.

We're going to try C45 today. The recommendation is more fuel and less timing so I'll follow what VP says and we'll see how it goes.

I also think the cam I have in the engine is too big. We're down a little bit of power from the smaller cam that was in it before. Doesn't really surprise me, at this power level the intake port is probably the choke point and not the valve lift. Valve lift is .890 gross which is probably more than it needs.

Is that the Crane cam you had done?

As I recall, that had pretty long duration.

What ignition timing did you have it at?....and what did you back it down to?

I originally had 36 degrees on race gas but backed it down to 34 and the engine ran a little better. With the Q16 I took another degree out to 33. With the C45 I dropped it down to 31 but after some testing we went back to 33 which worked the best.

Yep, I have a 282/288 Crane in it now with 481 lobes. The last cam was a Crane 280/286 with 452 lobes. I think the smaller cam made more torque but it is hard to compare. Last time I ran this engine was 3 years ago and the dyno was configured differently. So we could've lost some power from the camshaft, or the dyno cell, or the tuneup. I know I was running more timing and leaner mixture 3 years ago but I also hurt the cylinder head so I might have been on the ragged edge with that old tuneup.

Here is a video that shows a couple of pulls on Q16. Correction factor is 98% so we were correcting the power down all day. Engine ran strong all day. Oil filters were very clean so the engine isn't making any trash. The dry sump holds right at 10 inches of vacuum in the pan so not super high vacuum but enough to free up some power and keep the engine dry.

https://www.youtube.com/watch?v=2zTAGAy081o&feature=youtu.be

I loaded the 514 info into Controlled Induction and it recommends a 271/278 cam with .450 lobes and 109 lobe centers. So I'm about 10 degrees bigger than what Rick Jones thinks I need.

Any type of build I do along the lines of that motor is going in a bracket car, and pretty much all of my customers want motors that are relatively easy on parts/low-ish maintenance.

So, I end up coming at the cam situation from a different angle for that type of application.
The 470 TF testing showed that a faster valve opening rate and more lift do not always bring with them extra power. They pretty much always bring a little(a lot?) of extra wear and tear on the valvetrain.

Instead of looking at how much "more" power can be had from a higher lift, faster rate cam, and/or higher ratio rockers, I often think about how much power will not using something with a fast rate and high lift cost me? And, will the car still run the desired number while using a valvetrain that's easy(er) on parts?

Many times you're messing with 20-30hp(or less) difference between something that will live hundreds of passes with valvetrain parts and spring pressures that are more "middle of the road".
On a typical low-9 to low-8 second car, 20-30hp doesn't change the ET very much, but can make a noticeable difference in the maintenance and parts replacement costs and schedule.

Another aspect of running the motor in the car vs the dyno is, sometimes the cam is determined more by what the typical, or necessary rpm requirements are to get the combination to work well, and not solely by what makes the biggest number on the dyno.

I agree with that. If I was building a bracket motor then I'd go with a lower compression ratio, wet sump oiling and a softer cam. I'd probably stick with the other parts but perhaps a 1050 carb rather than the larger 1250 I have on there now. Engine would probably still make 825 hp but it would go rounds and last all season.

This engine was an R&D exercise to see how much power I could make with the EZ heads. I have some more tests to run with this combo then I'll pull it down and change the pistons over so I can run pump gas.

Yep, I'll take a more dependable w/a bit less power over max hp/high maintenance build unless it's an all out effort. I called Tim at Bullet because several on here said I could do better w/a different cam, well after a small discussion and my specs Tim said he didn't feel the additional power would be worth the added maint. My Isky roller is still kickin azz and is a pure joy to drive and very dependable w/less aggressive ramps............

Andy, do you have a good idea about how much power the dry sump is worth, not including the crankcase vacuum(you could get that back with a vacuum pump)?

I guess I wouldn't have thought there would be a 75+hp loss by running a slightly lower CR(13.5-14:1), a more valvetrain friendly cam, 1.7 rockers, wet sump oil system, and a vacuum pump, but I don't remember what you found the dry sump was worth.

I do not know for sure. I think the dry sump was worth more than 50 hp but some of that came from the pan vacuum so you could get that back with a vacuum pump. I think I'm going to try a wet sump on here just to find out. The dry sump is a killer setup but it is a hassle on the dyno. Lots of lines to hook up and it takes time to prime everything and then drain it all when done.

A big box type pan, or a regular car pan for the wet sump test?

I'll probably swap on the Milodon pan from my 470. That setup seems to be working just fine on the 470 with nice solid oil pressure across the entire pull. I think everything will fit on the 514 but I'll need to verify.

Here is a link to the article on the Hot Rod mag website:

http://www.hotrod.com/articles/modify-carburetor-run-oxygenated-race-gas/

Going EFI on this engine. Should be fun or if not fun then at least a learning experience.

Who's EFI are you using?

You may just cure yourself of carburetors.

Kevin

I'm waiting for the Holley HP system to arrive. They don't make a Mopar version so I'm getting the universal setup with a 4500 throttle body. I sent this intake back to Wilson for the bungs and fuel rail conversion rather than trying to do it myself.

I made my own trigger wheel and I'm in the process of getting a cam sync built. Should be up and running by early April.

The Holley system was on universal backorder for weeks and weeks but it finally showed up and I'm getting ready to fire it back up. Rich (Fast Man EFI) is flying into town to help with the dyno session so that should be fun. Lots of new parts this time around so I'm sure we'll be trouble shooting right and left.