Engine build suggestions please!

[7t500]

Feasibly, around $750-1k for the near future. Ideal for long term is new cam, RPM heads, rockers, maybe after all of that. I've been trying to do upgrades in phases and ensuring what I do will make current configuration better while also playing well into the end goal.

 

[Curiousyellow71]

Thanks for the update. It's good to hear of progress.

A 470 with a 268xe has got to a big change from your old 383.

My suggestion in your budget buy a dynamic 9 1/2 torque converter. Tight for street driving and keep the 3.55s rather then gearing deeper. Other companies have good luck with the 9 1/2 but the lupo's are mopar guys.
Install a new hydraulic cam but get a mopar grind instead of a comp cams xe. I don't know what you have for springs and compression to recommend a cam...plus it will probably all change if you upgrade the heads.

Did the 268xe come out of your 383?

Where do you think your peak power is at with the 268xe now?

 

[7t500]

Springs are Comp 911-16 (https://www.compcams.com/single-outer-valve-springs-1-524-o-d-1-110-i-d.html). Current compression comes out to about 9.5:1 with the 906 heads.

Yes, the cam came out of the 383 and if I had to estimate, I would be guessing peak power is around 425 hp, 450ft/lbs.

The reason I was thinking lifters now is that those will be an upgrade I need to make when I go with new heads/cam anyway and I would assume that I would see some gains over the stock stamped steel I am running now. I would ideally want to do both cam/heads at the same time and make sure to match the cam to the heads.

Yet again, these are my thoughts and what makes sense to me but I am willing to listen to those better versed than I in hopes I can learn

 

[BSB67]

Honestly, you can probably go in any direction now. As you mentioned, be sure today's actions are aligned with what you're final goal is. What is the final goal?

Its not clear to me what gear you have now. I probably would not mess around with a gear or converter at this time unless you have a 2.76 in it now and you plan on a huge cam in the next phase.

Also, earlier you mentioned having a 274 cam. What happened to that? Maybe I missed it.

What do you have now for exhaust? A good 2 1/2" mandrel bent exhaust with fresh mufflers is always good. If you have a cross flow muffler, replace them periodically. They'll deteriorate.

I would consider buying the heads next, then the cam and rockers together in the next phase. This way you'll get a clear picture of the motors performance with this cam, and help you make the right cam choice. You won't see any performance gain with new rockers now.

What pistons did you get, and what is your compression distance?

 

[Darter6]

The first time I built my 65 Belvedere, I did a 451 stroker using a 400 block Edelbrock RPM heads. Went with a TKO 5 speed and 3.73 gears. Very fun car on the road and drag strip.20 mpg and 11.90's at the track.One of the best combo's I ever had.

 

[7t500]

Final goal is a killer street car and capable cruiser. I have 2 gear sets, a 2.94 and a 3.55. The 3.55 is pretty noisy so I usually run the 2.94 and would love to have a quieter 3.55 or 3.73 to run.

I was mistaken with the 274, I thought that's what I had but I found the cam card in my files and I've got a 268.

Exhaust is a 2.5" mandrel bent x-pupe setup with ultraflos. The full exhaust setup is only 2 yrs old.

 

[BSB67]

Final goal is a killer street car and capable cruiser. I have 2 gear sets, a 2.94 and a 3.55. The 3.55 is pretty noisy so I usually run the 2.94 and would love to have a quieter 3.55 or 3.73 to run.

I was mistaken with the 274, I thought that's what I had but I found the cam card in my files and I've got a 268.

Exhaust is a 2.5" mandrel bent x-pupe setup with ultraflos. The full exhaust setup is only 2 yrs old.

 

[wyrmrider]

not that I like the old UBHarold 268 xe
use what you have if you have it- the 284 would be better
for either map out the torque curve and see how you like it as duration determines your power curve
run a compression check - keep good notes so you can estimate how big a change to make when you get a new cam
DO NOT do roller tip lifters without the B3 kit i.e save your money for the lifts you are involved with
you can buy a new cam - actually several for the price of roller rockers and a B3 Kit
The last 383 stroker with 906 heads I did I got a custom Crower
about the same seat duration as the magnum cam but .525 lift stock rockers worked fine
more lift with most pocket ported stock heads does not help much
The 268 will be "too small" for max HP but so what- you are going to change it later
keep track of where the intake closes- map it out with a degree wheel and check the comp catalog there is one where you can find timing at .006

 

[biomedtechguy]

Springs are Comp 911-16

Same springs I put on my stock 452 heads, 440 6bbl, heavy rods, steel crank, valve reliefs notched flat top pistons engine. Definitely a Purple Stripe cam, most likely the 292° /.509 cam. I also put the CompCams hydraulic flat tappet lifters in at the same time, and 10° Comp locks and retainers.
Old springs were worn out, weak pressure open and closed, as I suspected.
With the new CompCams parts, and the same old cam I described, my engine wants to, demands to go to 6,200 RPMs.
I have my shift light set at 5,800 and the rev limiter set at 6,200.
I can't wait for a chassis dyno session to see if what I "know" my butt dyno is telling me is true, or how far off I am. It would seem like the engine power would roll off sooner, and it may, but it sure doesn't feel like it!
Good luck!