350 Vortec Head Track Test Update

[af2]

From the best of my recollection with a turbo 400 when the shift selector is in 1st or 2nd gear it applies one or the other of the bands in the tranny . This was designed to induce drag on the drums helping with engine braking. In "drive" the bands are not applied. This needs to be addressed or else its like racing with your foot setting on the brake pedal in 1st and 2nd gear. I would have to search for my B&M trans pak instructions to find out what it was that I did to fix this. It might have been a check ball or a hole to drill. That is why some aftermarket Valve bodies have no engine braking they address the issue in the valve body. Dan

No band ever! 2nd gear is on it's own. That was one problem was, I have seen multiple failures from racers going to neutral at the end of the 1/4 mile and sending the drum though the floor as it spins 3 times the exit rpm.

[1980RS]

Still proves that Mark can make another smallish head into a ET killer machine.

Go to a divisional at Bir next year. Lots of guys do it.

Not going to happen in 2023, I was just told this week that NHRA canceled the Div 5 races at BIR next year. That sucks.

[Bigchief632]

Still proves that Mark can make another smallish head into a ET killer machine.

Go to a divisional at Bir next year. Lots of guys do it.

Not going to happen in 2023, I was just told this week that NHRA canceled the Div 5 races at BIR next year. That sucks.

Yes, that is really disappointing.

[ClassicComp]

Whats crank and rods do you run in this engine Mark?

[vortecpro]

Whats crank and rods do you run in this engine Mark?

GM cast crank, Callies rods 5.7

[ClassicComp]

7700 in the lights is putting it to the test

[1980RS]

7700 in the lights is putting it to the test

Bet that car had it's tongue hanging out at the end of the track for sure.

[vortecpro]

NEW BEST

60 1.381
330. 4.29
660 6.75
660 m 99.5
1320 10.69
1320 m. 122.1
https://youtube.com/shorts/8bV4CQBHr1E?feature=share
https://youtu.be/tP-vErEdyVA

[steve cowan]

NEW BEST

60 1.381
330. 4.29
660 6.75
660 m 99.5
1320 10.69
1320 m. 122.1
https://youtube.com/shorts/8bV4CQBHr1E?feature=share
https://youtu.be/tP-vErEdyVA

Great job Mark,
Was the good air available as you had wanted?

[vortecpro]

Thanks, NO its never how I want it. It was 1300 DA, 29.52 Baro, 50 GOW, cross wind. Now a great day at this track would be: 0 DA, 30.04 baro, 30 GOW.
The one thing I can say is this, Xtreme motorsports track IS THE BEST TRACK I'VE EVER RACED AT, they don't screw you on track prep, they don't limit your runs, owned by racers for racers. They let you do what you need to do, on the best surface I've ever raced on, bar none, 25 PSI tire pressure and I could have run more, where you gonna do that? We are very lucky to have this track 160 miles from us, and I will never have one hand tied behind my back ever again racing in Colorado"s horrible track prep combined with their 10,000 feet DA and 23.6 baro. And as a nice little bonus I got in some betting on a street race at the track

[289nate]

That’s great. Good on you. People forget we don’t just build an engine. We have to build something for it to go into that deserves much more attention.

[econo racer]

Mark I tried a 357 sbc vortec heads. with 373 gears a 4K TCI. 268 comp extreme flat tappet with proper springs etc. RPM intake 750 holley and the best I went was about 13.3 1/4. Man mine was a failure. weighed about 3500 lb. I went back to the 400.

[sjre]

Mark I tried a 357 sbc vortec heads. with 373 gears a 4K TCI. 268 comp extreme flat tappet with proper springs etc. RPM intake 750 holley and the best I went was about 13.3 1/4. Man mine was a failure. weighed about 3500 lb. I went back to the 400.

Do you really think this is a stock vortec headed 355 ? This is more a high end stocker motor with alot of tricks done to engine and drivetrain. No matter what !

[steve cowan]

Agree,
People trying to learn including my self should study the video,look at where the converter and gearing puts the rpm from the hit,through the entire run.
In the sweet spot.
It's all in the 60ft,you can't make it up in the back half as the mph tells us that.

[skinny z]

It would be interesting to see an RPM trace over an entire run. I suspect the RPM window is very tight.
This ties into a conversation earlier where I compared my weak ET vs predicted HP. I said 400 to 425. Vortecpro countered with "probably less". More like 350. Then it dawned on me that this was really a discussion about average HP.
It made a lot of sense at that point and it directed me to not just make more HP (which I hope to), but keep the rev range where it needs to be for a higher overall average.