454 stroked to a 496

[Bwear]

I am needing to rebuild my 454 in a 2000 chevy 4 door. I am thinking of installing a 496 stroker kit when I do. I am going to have the heads redone. A new cam. Injectors. And hoping to have blackbear tune it. Will all of this work together with stock heads and intake? Wanting suggestions on parts and info if anyone has done it. What can I look at torque numbers over the 454? Still wanting to tow. So no crazy cams

 

[Schurkey]

The L29 heads are flow-limited. Add more displacement, and the peak RPM goes down.

I had L29 heads in my boat. 454, bigger cam. The heads were all done at just over 5K RPM. Cam should have been good to 6K+.

 

[L31MaxExpress]

The L29 heads are flow-limited. Add more displacement, and the peak RPM goes down.

I had L29 heads in my boat. 454, bigger cam. The heads were all done at just over 5K RPM. Cam should have been good to 6K+.

I feel the manifold is probably more flow limited then the stock heads though. With its long runners it is going to dictate the power curve far before the heads. I have always wanted to send one to extrude hone to get it flowing even what the stock heads flow. A dual plane intake and a carb provides a substantial horsepower gain but gives up midrange torque even with the stock cam and stock heads. I think a 496 with a little more compression and a well matched cam could easily crank out another 100 ft/lbs or more from off-idle through most of the midrange.

 

[8flat]

Hey Bwear I am literally in this exact thought process, planning out a rebuild of my '94 454. Machinist is trying REAL hard to talk me into the stroker kit because it not only makes more torque/hp but makes a nice and tidy "square" engine, one of the reason the 8.1 was such a good platform (I had one, and still regret selling it).
So, biggest question is do we ditch our peanut port heads. Well, I'm working with a cam designer, PM me if you'd like his name, dude is really good. In a nutshell, the PP heads on a 496 with a good roller cam upgrade actually work slightly better off-idle up to about 3800RPM as compared to a big oval port head (781 or 049). I can send graphs if you'd like. The big ovals pull out ahead in the 4,500rpm range and at 5 or 5,500 perform way better. But for my use case, just pulling trailers, I don't care to rev it that high anyway.

My machinist HATES this idea though. hahaha I think he's rolling his eyes at me, thinking "damn kids and their computer dynos". He swears I need to go with better heads that flow more than the peanut ports.

 

[454cid]

Hey Bwear I am literally in this exact thought process, planning out a rebuild of my '94 454. Machinist is trying REAL hard to talk me into the stroker kit because it not only makes more torque/hp but makes a nice and tidy "square" engine, one of the reason the 8.1 was such a good platform (I had one, and still regret selling it).
So, biggest question is do we ditch our peanut port heads. Well, I'm working with a cam designer, PM me if you'd like his name, dude is really good. In a nutshell, the PP heads on a 496 with a good roller cam upgrade actually work slightly better off-idle up to about 3800RPM as compared to a big oval port head (781 or 049). I can send graphs if you'd like. The big ovals pull out ahead in the 4,500rpm range and at 5 or 5,500 perform way better. But for my use case, just pulling trailers, I don't care to rev it that high anyway.

My machinist HATES this idea though. hahaha I think he's rolling his eyes at me, thinking "damn kids and their computer dynos". He swears I need to go with better heads that flow more than the peanut ports.

You have a Gen5 TBI. The OP has a Vortec engine and doesn't have the same heads that you do. He already has large oval port heads.

 

[LC2NLS6]

I had my 93 gen V 454 rebuilt, 9.2:1 domed pistons and kept my low flowing peanut ports. She pulls hard to 5000, which is fine with me, and over a better head, I bet I won't see much of a gain under 5000, it at all. Weiand dual plane alum peanut intake and Holley sniper EFI. Comp magnum 215/215 .566/.566 lift 110 LSA hyd roller cam. Comp 911 springs and comp roller rockers with custom short polylocks to fit under the stock valve covers. Tons of low engine speed torque and good around town and getting on the highway. Go look at richard holdeners BBC videos on youtube. He does Gen V vs Gen 6 454 w/ cam, etc upgrades, 496's etc too.

 

[8flat]

You have a Gen5 TBI. The OP has a Vortec engine and doesn't have the same heads that you do. He already has large oval port heads.

**** sorry, I missed that, you're correct. Those are good heads on the Gen6 from everything I've read.

 

[8flat]

I had my 93 gen V 454 rebuilt, 9.2:1 domed pistons and kept my low flowing peanut ports. She pulls hard to 5000, which is fine with me, and over a better head, I bet I won't see much of a gain under 5000, it at all. Weiand dual plane alum peanut intake and Holley sniper EFI. Comp magnum 215/215 .566/.566 lift 110 LSA hyd roller cam. Comp 911 springs and comp roller rockers with custom short polylocks to fit under the stock valve covers. Tons of low engine speed torque and good around town and getting on the highway. Go look at richard holdeners BBC videos on youtube. He does Gen V vs Gen 6 454 w/ cam, etc upgrades, 496's etc too.

After reading your thread a while back, I asked a cam designer I know (Lee Atkinson) to run these scenarios through his software last week. PP heads actually make MORE torque and about the same HP everywhere under ~3800RPM. It wasn't a lot more, only about 10ft lbs, but it was definitely noticeable on graphs. The PPs really only fell apart as compared to 049s at around 4700rpm or so. But I'm like you, I'm building a toy hauler, not a drag car, having the power taper off quick at a 5k redline is really no problem at all. My machinist thinks I'm crazy, but unless the dyno software is completely wrong, the PPs work quite well.
Cool stuff. I bet your gen V runs like a champ. Lee's cam ideas were very similar to your cam specs.
One question: did you have to drill out the heads to accept studs for the roller rockers?

 

[LC2NLS6]

After reading your thread a while back, I asked a cam designer I know (Lee Atkinson) to run these scenarios through his software last week. PP heads actually make MORE torque and about the same HP everywhere under ~3800RPM. It wasn't a lot more, only about 10ft lbs, but it was definitely noticeable on graphs. The PPs really only fell apart as compared to 049s at around 4700rpm or so. But I'm like you, I'm building a toy hauler, not a drag car, having the power taper off quick at a 5k redline is really no problem at all. My machinist thinks I'm crazy, but unless the dyno software is completely wrong, the PPs work quite well.
Cool stuff. I bet your gen V runs like a champ. Lee's cam ideas were very similar to your cam specs.
One question: did you have to drill out the heads to accept studs for the roller rockers?

No they are drilled from the factory, with factory guideplates on the gen V. Had to have the poly locks shorter to clear the valve covers though.

On a trip to town and back, I'm over 4000 rpm exactly maybe 3 times for maybe 1-2 seconds. Most of the time its 2500-3000 rpm cruising.

 

[yevgenievich]

L29 style oval ports. But still thinking of changing to brodix ovals.

You must be registered for see images attach

You must be registered for see images attach