HT502 compatible with L29 intake etc?

[TexasAggie]

I've been eyeing the HT502 crate motor for my '99 Suburban... current 454 runs fine, but leaks a bit and has ~185k miles. Would love more juice under the hood and like the idea of a crate motor so that the truck doesn't have to be down for months during a rebuild.

I've done a fair amount of interweb research but haven't found anything definitive.... Is the HT502 a drop in replacement for the '96-'99 Vortec 7.4? Will the intake bolt up? Does the block and heads have all the sensor holes, etc? I would expect to have to do a few upgrades to the fuel system and PCM programming, exhaust, etc, but I would do these things with any engine swap. Not looking for anything more than what the HT502 is rated for. 500+ lbft would be awesome!

Let me know what y'all think. I'm not in a hurry... trying to do all the research to understand the pros and cons of each option before deciding anything.

 

[454cid]

I can't address the need/want for power, or specifics on the HT502, but are you thinking 185K is high mileage for a 454? I'm almost at 300K miles, and yes it does leak, but runs fine..... hopefully, next week when I'm off work, I'll address some of the leaking (valve cover gaskets that have likely turned to stone).

 

[TexasAggie]

No, not high mileage... I don't drive it a ton and am sure I could get another 10 years out of it. Just itching for more power!

 

[yevgenievich]

Mostly everything should swap over. Intake will need some work done to it to get advertised hp for 502.

 

[OCD INC]

I've been eyeing the HT502 crate motor for my '99 Suburban... current 454 runs fine, but leaks a bit and has ~185k miles. Would love more juice under the hood and like the idea of a crate motor so that the truck doesn't have to be down for months during a rebuild.

I've done a fair amount of interweb research but haven't found anything definitive.... Is the HT502 a drop in replacement for the '96-'99 Vortec 7.4? Will the intake bolt up? Does the block and heads have all the sensor holes, etc? I would expect to have to do a few upgrades to the fuel system and PCM programming, exhaust, etc, but I would do these things with any engine swap. Not looking for anything more than what the HT502 is rated for. 500+ lbft would be awesome!

Let me know what y'all think. I'm not in a hurry... trying to do all the research to understand the pros and cons of each option before deciding anything.

So have you done the swap yet? did the l29 intake work? I am considering this swap as well.

 

[yevgenievich]

So have you done the swap yet? did the l29 intake work? I am considering this swap as well.

I have l29 intake on 488 and it does run out of breath around 4900rpm

 

[Supercharged111]

I have l29 intake on 488 and it does run out of breath around 4900rpm

Richard Holdner has a video where he dyno'd the stock L29 intake vs a carb'd intake, stocker started to choke at 4500. My truck pulls happily to the 4700 shift point, thinking I may bump it a smidge. They are most definitely done before 5000.

 

[yevgenievich]

Richard Holdner has a video where he dyno'd the stock L29 intake vs a carb'd intake, stocker started to choke at 4500. My truck pulls happily to the 4700 shift point, thinking I may bump it a smidge. They are most definitely done before 5000.

Took a look at the logs, at 80ish % throttle, MAF lb/hr rate drops off around 4k rpm and almost flat lines about 4700-4800rpm. But my tune is not all on point yet either. I was hoping to limp alone with stock intake until boost can take care the deficiency of the flow. However, at about 2900 rpm it feels like kick in the back and pulls hard until around 4k rpm where it starts to drop off. I also do not remember what a stock 454 drives like any more either.

 

[TexasAggie]

So have you done the swap yet? did the l29 intake work? I am considering this swap as well.

Negative. Been poking around looking at different possibilities, but really just dreaming at this point. Probably will have to wait until the current 454 gives me trouble. Sure would be fun to drive around with more power under the hood though.

 

[lukeapre]

Love to hear if anyone does this swap. Looking for a "bolt in" swap for all the same reasons in my 99 2500 sub.