SBC 383 500ft/lb torque build

[NewbVetteGuy]

If you want a lot of torque, you can always drop one of these in it. I made the prototype cams for it.
https://cumminsengines.com/nissan-titan

Or turbo charge the 383.

Or this freak-of-nature: https://www.trucks.com/2018/01/15/detro ... up-engine/


Adam

[randy331]

Don't think it will happen, unless you have more ci.
https://www.speed-talk.com/forum/viewtopic.php?f=1&t=43195
Remember this one?

That's an expensive and not very good example of a good tow engine.

Randy

[Orr89rocz]

Don't think it will happen, unless you have more ci.
https://www.speed-talk.com/forum/viewtopic.php?f=1&t=43195
Remember this one?

That's an expensive and not very good example of a good tow engine.

Randy

Its towed 14,000 lbs just fine and got 10.7 mpg doing so if i recall. I’d say that works pretty darn good

[gottago]

I thought the OP was looking for near stock looks and the best he could do with that?

[77cruiser]

Don't think it will happen, unless you have more ci.
https://www.speed-talk.com/forum/viewtopic.php?f=1&t=43195
Remember this one?

That's an expensive and not very good example of a good tow engine.

Randy

I think it was built for dual purpose tow & some performance, like tuning up a diesel but not having one.

[gnicholson]

Ill tell you what i would do for a simple sbc that would tow great. 383 or better yet 406. Vortec heads 9.5 to 10 to 1, small cam on a tight 106 single pattern cam installed four degrees advanced. Qjet 15/8 headers and a 2.5 into 3 inch single exhaust. I built one just like this and although it wasnt dynoed it felt like it had 100 more inches pulling a 5000 lb trailer. Mileage was avg without a load but was very good pulling a trailer.

[mtmvette]

Ok... lot of good info. I think I read somewhere that the GM crate 383 made a little more than the advertised torque of 444. Granted these numbers are not equal unless every engine was dynoed on the same machine at the same time. If GM makes an over the counter 383 engine with 450ft/lbs, surely some one could tweek it with a cam and tricky cam timing???? Just thinking.

[GARY C]

Don't think it will happen, unless you have more ci.
https://www.speed-talk.com/forum/viewtopic.php?f=1&t=43195
Remember this one?

That's an expensive and not very good example of a good tow engine.

Randy

Its towed 14,000 lbs just fine and got 10.7 mpg doing so if i recall. I’d say that works pretty darn good

In the context of the thread I think it's a good example that 500ft lb 383's don't grow on trees even if it's a money tree.

[GARY C]

Ok... lot of good info. I think I read somewhere that the GM crate 383 made a little more than the advertised torque of 444. Granted these numbers are not equal unless every engine was dynoed on the same machine at the same time. If GM makes an over the counter 383 engine with 450ft/lbs, surely some one could tweek it with a cam and tricky cam timing???? Just thinking.

Given that example you are prbably looking at + or - 6 ft lbs.

[randy331]

That's an expensive and not very good example of a good tow engine.

Randy

Its towed 14,000 lbs just fine and got 10.7 mpg doing so if i recall. I’d say that works pretty darn good

In the context of the thread I think it's a good example that 500ft lb 383's don't grow on trees even if it's a money tree.

They may not happen easily, but if I spent that much, I'd expect better results.
I think the OP is unlikely to get 500 lbs or even 475 within what he has posted. Non roller block would suggest hyd flat tappet, that won't help.
The vortec heads are good choice but in un ported form aren't gonna produce the tq he's wanting.

For a build like the OP is talking about, I wouldn't focus on full throttle power, but how to make good power over a wide rpm range, and mainly at part throttle. It will spend 99% of it's time at part throttle.

I've built a couple of those type of tow engines recently that I'm happy with.

Randy

[GARY C]

Its towed 14,000 lbs just fine and got 10.7 mpg doing so if i recall. I’d say that works pretty darn good

In the context of the thread I think it's a good example that 500ft lb 383's don't grow on trees even if it's a money tree.

They may not happen easily, but if I spent that much, I'd expect better results.
I think the OP is unlikely to get 500 lbs or even 475 within what he has posted. Non roller block would suggest hyd flat tappet, that won't help.
The vortec heads are good choice but in un ported form aren't gonna produce the tq he's wanting.

For a build like the OP is talking about, I wouldn't focus on full throttle power, but how to make good power over a wide rpm range, and mainly at part throttle. It will spend 99% of it's time at part throttle.

I've built a couple of those type of tow engines recently that I'm happy with.

Randy

Not cheep for sure but I wouldn't consider it poor by any means, it would be interesting to know if a single carb set up would have hurt the power. I think in the rpm range I would have opted for a little smaller head but I may be wrong.

[RevTheory]

Ill tell you what i would do for a simple sbc that would tow great. 383 or better yet 406. Vortec heads 9.5 to 10 to 1, small cam on a tight 106 single pattern cam installed four degrees advanced. Qjet 15/8 headers and a 2.5 into 3 inch single exhaust. I built one just like this and although it wasnt dynoed it felt like it had 100 more inches pulling a 5000 lb trailer. Mileage was avg without a load but was very good pulling a trailer.

This is probably about right. It is what it is...

[bigfoot584]

Ill tell you what i would do for a simple sbc that would tow great. 383 or better yet 406. Vortec heads 9.5 to 10 to 1, small cam on a tight 106 single pattern cam installed four degrees advanced. Qjet 15/8 headers and a 2.5 into 3 inch single exhaust. I built one just like this and although it wasnt dynoed it felt like it had 100 more inches pulling a 5000 lb trailer. Mileage was avg without a load but was very good pulling a trailer.

I built an engine similar to this, 383", 10.4 cr, 180cc protopline alum. heads,
airgap intake, 226/226, lsa 108 HR cam with E85 on the dyno made 492 torque, 450 HP,
would've like to try 91 or 93 octane fuel but didn't have any with at the time.

[ptuomov]

Don't think it will happen, unless you have more ci.
https://www.speed-talk.com/forum/viewtopic.php?f=1&t=43195
Remember this one?

That's an expensive and not very good example of a good tow engine.

Randy

It may be expensive, but why do you say it's not a good for a tow engine?

[gmc406]

Going from a tired old 350 with 300ft/lbs on a good day to nice fresh 383, is going to absolutely no comparison.

Just build the 383 and get what you get. You won’t be disappointed, even if it “only” makes 450ish ft/lbs. The 383 will do what you want.

Or go 406 and get just a little more.