HT383E into a K3500

[Tachyon]

I have seen a few things in searching for an answer here and there, that does prove that people have put the GM 383 motors into bigger trucks. Most the info I read says the HT383E motor is a direct swap for a 350, but mostly says in 1/2 ton trucks. I am looking for an answer and/or opinion about putting this motor in my truck, and if it’s possible, maybe a good parts list as well. My truck is a ‘99, CCLB K3500. It is absolutely all stock, with a NV4500 5 speed and 350 motor, with 345,000 miles on it. The truck is still running pretty good, but is starting to get a little tired, so I’m working on getting my list together and mentally prepared to take the plunge, and really hope to add more power over the 5.7, using the 383 if truly it is a candidate for my truck.

Thanks

As you can see from my signature, I have done this swap in a 3/4 ton truck. From my own research prior to this swap and from the people I've talked to, my best guess is simply that GM didn't bother to re-certify the emissions for this swap on anything but a 1/2 ton vehicle. I can confirm that it works great and there are no issues with the factory PCM or aftermarket tuners. In fact I'm fairly certain that there's no difference in the factory software between a 1500 and a 2500. I'm guessing the 3500 also.
I also looked at the 454, but that's not a direct drop in swap plus I was concerned about future inspections or emissions issues which the HT383E has no issue with.
Because of it's slightly hotter cam and roller lifters, the HT383E puts out power numbers similar to the factory 454 anyway. With minimal work, you can well exceed the stock 454's numbers fairly easily.
Stock 454: 290 HP @4000, 410 lb-ft @3200
Stock HT383E: 323 HP @3200, 444 lb-ft @3000

This is without other upgrades. Using G-Meter type tests mine is closer to 400HP/500lb-ft by adding good airflow from intake to exhaust, including headers, and a performance tune. Plus I'm still "legal". At this point I don't regret going with the HT383E over a stock 454 at all. Plus the HT383E has heavier duty components like forged crank, roller rockers, etc. which was my main reason for going with this swap, gaining a tough, reliable engine that would last a long time and tow like a son of a gun. All mission accomplished.

The only thing you'll want to watch is your RPM. With a stick it's easier to blip up past redline and I wouldn't want to do this to a stroker like the HT383E regularly. No biggie, just a thought.

 

[Supercharged111]

A lot of you guys seem to be forgetting that the HT383 ratings are with carb and headers, not spider injection, manifolds, and 1.75" head pipes.

 

[Christian Steffen]

A lot of you guys seem to be forgetting that the HT383 ratings are with carb and headers, not spider injection, manifolds, and 1.75" head pipes.

The gm numbers are probably with a good intake and long tube headers, really the perfect scenario. Plus they probably didn't have accessories.

Not downplaying the 383, but it's not going to make the advertised numbers without a fair deal of work.

 

[Tachyon]

A lot of you guys seem to be forgetting that the HT383 ratings are with carb and headers, not spider injection, manifolds, and 1.75" head pipes.

That's correct for the HT383, which is a completely different engine package. The HT383E is rated as a factory fuel injected engine using the original L31 intake, exhaust, and fuel injection. I can vouch for those factory rating numbers. I can also tell you that headers, performance exhaust, intake, and tuner will bring those numbers up significantly.

The numbers I quoted are right from the GM dyno sheet for the HT383E. In fact those numbers are higher than the original GMPP ratings which were based on a carburated setup based on the HT383. They now have updated, real numbers.

This is a solid motor with good power that makes great power with minor external addon modifications.

 

[shovelbill]

If the truck originally came with the 5.7, it won't be an issue. He should still get it tuned though, the change in displacement really needs to be accounted for; sure, it'll run off of the stock tune, but it won't be correct.

i concur.......i haven't had my truck tuned for monetary reasons....read; i haven't been able to even pay attention.....but i can can tell you, the difference is shocking, with the stock tune. she did learn a bit over time i can tell you....computers and O2's ain't all that evil s i thought..........and i sure as hell recommend doing the spider MPFI conversion BEFORE you do the engine swap..i didn't and i regret it......that's what's next on my mind....and the tune of course.

it's not only a difference in volume....there's a timing and cam difference as well.....

That's correct for the HT383, which is a completely different engine package. The HT383E is rated as a factory fuel injected engine using the original L31 intake, exhaust, and fuel injection. I can vouch for those factory rating numbers.

The numbers I quoted are right from the GM dyno sheet for the HT383E. In fact those numbers are higher than the original GMPP ratings which were based on a carburated setup based on the HT383. They now have updated, real numbers.

with the exhaust we have and it air intake, i have the Volant to your K&N, wold you think we could gain an additional 5%-10% with your tuner as opposed to a full Black Bear reprogram?

i gotta go back and re-read your build up thread......you did get the same numbers GM posted at the rear wheels as i reacall.....or very close.

 

[Tachyon]

i concur.......i haven't had my truck tuned for monetary reasons....read; i haven't been able to even pay attention.....but i can can tell you, the difference is shocking, with the stock tune. she did learn a bit over time i can tell you....computers and O2's ain't all that evil s i thought..........and i sure as hell recommend doing the spider MPFI conversion BEFORE you do the engine swap..i didn't and i regret it......that's what's next on my mind....and the tune of course.

it's not only a difference in volume....there's a timing and cam difference as well.....


with the exhaust we have and it air intake, i have the Volant to your K&N, wold you think we could gain an additional 5%-10% with your tuner as opposed to a full Black Bear reprogram?

i gotta go back and re-read your build up thread......you did get the same numbers GM posted at the rear wheels as i reacall.....or very close.

I'd love to get a full tune, but I really don't know the local players well enough to trust one and spend that kind of money. Frankly I've been pretty happy with the Hypertech tune. It was never my intention to hotrod this truck, just to get a bulletproof reliable engine with more towing power. The extra power I've gotten over what I expected has just been a happy bonus. Though it's nice having a 6000+ lb vehicle that feels like it weighs half that.
I'm not sure why, but for some reason this swap and the HT383E in particular really don't get the respect they deserve, particularly considering you end up with a fully emissions legal truck that passes any inspections you can throw at it. Something that's more important every year as regulations tighten.
The other nice thing is that the engine clearly has the strength and potential for much more power. I had thought that some head porting, higher ratio rocker arms, and matching springs would really perk it up and I have no doubt it would handle a Paxton type supercharger for someone that wanted to really perk things up.

And we both totally agree on the importance and value of doing the MPFI spider conversion when doing this swap. So worth it.

As for the power numbers, as I said, I was surprised to get confirmation not only in the factory GMPP power numbers initially, but in significantly higher numbers once I added the mods that I've added to let the engine breathe and get fuel. No regrets.

 

[shovelbill]

what's funny...talking about emissions. when i bought the 383 i was ordering the ceramic JBA headers(with EGR), single sided JBA CAT back and the Volant air box at the same time. those items i got from Auto Anything, was the best prices i ever found at that time.....
Jegs sent me the engine but wouldn't send the high flow Magnaflow CAT setup, neither would Summit as NY is a ****** CARB compliant state.....i couldn't even put the part in my shopping cart........when i called them about it they said "nope, not to NY"

i ended up getting it from a Magnaflow "outlet" in Canada......it was shipped from a warehouse the US though, Colorado i think.....and i got it for $317 as opposed to the $500+ that the others wanted. technically the HT383E is not Carb compliant either, go figure.

 

[Christian Steffen]

That's correct for the HT383, which is a completely different engine package. The HT383E is rated as a factory fuel injected engine using the original L31 intake, exhaust, and fuel injection. I can vouch for those factory rating numbers. I can also tell you that headers, performance exhaust, intake, and tuner will bring those numbers up significantly.

The numbers I quoted are right from the GM dyno sheet for the HT383E. In fact those numbers are higher than the original GMPP ratings which were based on a carburated setup based on the HT383. They now have updated, real numbers.

This is a solid motor with good power that makes great power with minor external addon modifications.

My bad, didn't realize they had one specifically for the efi trucks.

i concur.......i haven't had my truck tuned for monetary reasons....read; i haven't been able to even pay attention.....but i can can tell you, the difference is shocking, with the stock tune. she did learn a bit over time i can tell you....computers and O2's ain't all that evil s i thought..........and i sure as hell recommend doing the spider MPFI conversion BEFORE you do the engine swap..i didn't and i regret it......that's what's next on my mind....and the tune of course.

it's not only a difference in volume....there's a timing and cam difference as well.....


with the exhaust we have and it air intake, i have the Volant to your K&N, wold you think we could gain an additional 5%-10% with your tuner as opposed to a full Black Bear reprogram?

i gotta go back and re-read your build up thread......you did get the same numbers GM posted at the rear wheels as i reacall.....or very close.

Yes, they can carry the long term trims over, but it still won't be perfect. The fueling when in PE is what really needs tuning.

And I know there was more than a straight volume change. The reason I bring up volume is a great deal of the fueling is calculated off of the volumetric efficiency table; which references the cylinder volume to know how much air the engine is consuming, then cam and compression changes are also going to mess with it. Bottom line, the VE table should really be retuned, along with the MAF.

And then not to mention that there is likely a fair deal of power being left on the table by not tuning the timing.

You guys can run how you want, if it works for you then more power to you; but if the OP can he should have the truck tuned to really take advantage of the new engine.

 

[Supercharged111]

That's correct for the HT383, which is a completely different engine package. The HT383E is rated as a factory fuel injected engine using the original L31 intake, exhaust, and fuel injection. I can vouch for those factory rating numbers. I can also tell you that headers, performance exhaust, intake, and tuner will bring those numbers up significantly.

The numbers I quoted are right from the GM dyno sheet for the HT383E. In fact those numbers are higher than the original GMPP ratings which were based on a carburated setup based on the HT383. They now have updated, real numbers.

This is a solid motor with good power that makes great power with minor external addon modifications.

Show me, because I'm not believing the rating with stock tune, intake, and exhaust in a 1500. Not in a million years.

http://www.chevrolet.com/performance/crate-engines/small-block-ht-383e

This page doesn't specify how the engine was equipped to make those numbers.

 

[shovelbill]

My bad, didn't realize they had one specifically for the efi trucks.



Yes, they can carry the long term trims over, but it still won't be perfect. The fueling when in PE is what really needs tuning.

And I know there was more than a straight volume change. The reason I bring up volume is a great deal of the fueling is calculated off of the volumetric efficiency table; which references the cylinder volume to know how much air the engine is consuming, then cam and compression changes are also going to mess with it. Bottom line, the VE table should really be retuned, along with the MAF.

And then not to mention that there is likely a fair deal of power being left on the table by not tuning the timing.

You guys can run how you want, if it works for you then more power to you; but if the OP can he should have the truck tuned to really take advantage of the new engine.

thanks for your reply......yes, i do understand the VE tables...that's how i tuned my space ship Harley, by the VE tables.....it's close, but i never put it on a dyno.

my mechanic does have a dyno.....i was there the other day going over all the **** i need done on my frontend...not to mention my a/c controls.......but i know he'll do a real good job on the tuning, just don't know what he'll charge me for a true dyno tune....in reality if i just save a few more dollars i'll get a WAY better product than if i go with the Hyprchip deal.....not that's that's a bad option......buy once, cry once for real.......

i couldn't believe the difference in tune i needed JUST from a cam change in my pretty modified Dyna........

imagine the XR750 Harley motor....she was sucking in 115% on the volumetric efficiency.....now that's sure maximizing. intake and exhaust are CRITICAL for a real proper running machine.

Show me, because I'm not believing the rating with stock tune, intake, and exhaust in a 1500. Not in a million years.

http://www.chevrolet.com/performance/crate-engines/small-block-ht-383e

This page doesn't specify how the engine was equipped to make those numbers.