My New Pump Gas 505!
 

Dynoed the new motor yesterday, made 8 pulls, last one we tried 26 degrees, 7th was the best for the day@28 degrees timing and 112 BLP jets, we stopped there as it was heat soaked, hopefully finish it up later today and pull it higher to see what it looks like up top, I'm totally stoked with the new build and the early numbers its showing! 91 Octane and same KRE D Ports from last motor

https://i.imgur.com/i9y3WiB.jpg

Looks great!


Congrats!


:)

Very nice

Very impressive! I see that it liked 29 degrees timing best, and I've read and heard others say the same thing. For some reason the engines I've built with those heads always showed they liked around 32 degrees best on the dyno. Don't really know why. Congratulations though, great numbers!

Good job Darby! Nice build.

Congrats, good job

Awesome !

Something I've learned from a few dyno sessions - be sure to use you own timing light at the dyno session and not rely on the dyno operators light. I had an experience where there was a slight difference between the 2(his was a dial back and mine a old conventional). Great numbers either way.

Thanks Brad! I agree, I brought mine to use, and once were done i'll verify what mine says compared to his, and well also be using my digital7 ign box and coil, that way its how it is when in my car, yesterday was his 6al analog box and tower coil, and we only did that cause we knew it worked to get the tune in order for the most part.

Nice
Did you just up displacement and maybe cam change?
Will be interesting to see how the car picks up.

Great numbers. What is the cam and what are BLP jets? What was the BSFC numbers?

Awesome congrats! What cfm on the heads?

Good numbers! Now get that thing in the car for some shake down runs!

Bruce, Cam change also, 55mm LSM Cam, Ls FIRING Order, .904 morel bushed lifters

55 mm LSM cam, ls firing order, 270/276@112 LSA, Bolaws Performance carbs .112 orifice size, The one earlier pulls showed a avg of .415!! She's efficient as hell!

Heads on a tight flow bench and a 4.18 bore were 325@700, Probably about 335-340 on this bigger bore.

Thanks Skip! That's the next plan after we find its final numbers, we haven't even pulled the covers and relashed the valves yet :)

Great numbers bro.

Nice results, Darby!

Darby, so how fast will it push the Grandville, instead of the Firebird?...……….LOL

BTW nice numbers!!!

An average of 0.415 BSFC is incredible. What A/F readings were you getting? I know my car has the best times at 12.8 A/F.

If I still had it, pretty damn fast ,lol

They were pretty much where they were with last motor high 15 low 16, Just The BSFC Is even better on this one. He goes by EGT and how the plugs look as well, Those afr numbers aren't accurate, but he knows his dyno and knows that Doms always read high.

Nice build!

uh 8s Darby. Nice combo.

Nice numbers Darby. I see the numbers were still climbing . Never tried any pulls past 6400 RPMs ?
Its going to be a blast your first time out at the track.

Thanks Conrad! Troy were gonna pull it higher today , stay tuned!

Darby, did you dyno the last motor? What size is the carb?

NICE!
Great build! Should be a lot of fun.

Great power.

What head flow?

our ET / MPH computed from your vehicle weight of 4500 pounds and HP of 728 is 10.69 seconds and MPH of 126.42 MPH.

Pretty baddass "little" motor with d ports.:)

Nice build Darby. Have fun

Darby, at .415 BSFC your engine is 10-15 percent more efficient than an average high performance engine (.38-.39). Well done! Measuring EGT verses A/F ratio is a far more accurate picture of combustion efficiency. Higher EGTs = more complete combustion and more HP. What stroke are you runnIng?

Yes I did Scott, it made 651@6500, same carb on that motor that’s on here, my 1050 Dom.

Thanks!! We made some more pulls today, and they were a tad higher on avg at .423 still not bad!! 4.25 stroke.

Final numbers today! I’m pretty excited about this motor!! Plugs look Awesome for pump gas!!

Good job Darby! Great numbers.

Very impressive numbers on pump gas and D ports!

Nice job!

Thanks guys! Here’s one of the runs
https://youtu.be/fAwafpKSbEw

.458 BFSC at 6800 rpm for an NA non Diesel engine is incredible! Spark plugs are dead on.

Nice build Darby

Nice,somebody knows something about good machine work and parts.

Nice build there Darby. 650 to 750 at a higher RPM I assume. What else are you changing when this motor goes in?

Probably his underwear after his 1st launch

Possibly Bud! lmao

Peaked 100 Rpm sooner then old motor, torque was actually 1-200 higher on this bigger motor, Lenny has my numbers for the conv change. I've changed a lot on the car to help with added power I added sub frame connectors, and lost some weight to offset the added weight of the block!! It may end up a tad lighter well see.

That thing will be a hand full on the street.

That 666 max torque with the .6 added on might scare him at night too.:eek: