Another 7.4 l29 cam question...

[felskee]

I cannot for the life of my get a consistent answer on what is needed on a cam swap for a 97' 454.
Some people say you can use the stock stuff, others say adjustable is the only way to go...milling valve guides, not milling etc.
Would like to clarify for the next guy so it has all the information in one spot.
I know what cam i want, i just need some guidance/ part numbers on:

springs/retainers/etc.
pushrods
rockers/studs
lifters

TIA

 

[Scottm]

Check my build thread below. I ported my heads, had the guides milled down, went to Comp springs, spacer cups and retainers, and the Comp rocker studs and magnum rockers for full adjustment. The stock gen 6 7.4 cam is absolute junk, no lift, no duration and an absurd 116 degree lsa. I wanted a Comp cam 1.5 years ago but they were backordered til the cows come home. So I had my stock cam reground at Delta last year for more lift and duration with less lobe sep angle. The Comp cam I want is a 01-411-8, and they will be back in stock in Feb. So I ordered one and I'm waiting til then to put it together.

99 L29 454 build

I made a few posts on my 454 rebuild and hop-up in the general vortec thread that really should be in a new thread, so here it is.. My 97 K3500 extended cab dually has 230,000 hard miles, so I bought a L29 7.4/454 from a rolled suburban to rebuild and swap in. It allegedly had under 20k miles...

www.gmt400.com

 

[Schurkey]

Gen 5/6 has "net lash" lifter preload as delivered from GM. If your cam has the same base-circle diameter as stock, you're good-to-go with the stock rocker studs, rocker arm, pivots and nuts. Provided, of course, that the overall lift doesn't get you into trouble with coil bind, retainer-to-seal clearance, etc.

When I put L29 heads on my boat, I converted to adjustable rocker studs using the stock base thread, I scrapped the valve rotators on the intake and exhaust valve springs in favor of rotator-eliminator shims. Gotta be careful on the intakes, the eliminator shims can interfere with the radius between the valve guide and the spring pocket. Had to grind clearance into four intake spring pockets. I also used Comp Cams Pro Magnum steel roller rockers, but probably wouldn't have "needed" to.

 

[Piratehunter]

I used the comp cam 01-415-8, 911-16 springs, 612-16 locks, 4779 rotator eliminaters, 748-16 retainers, 4514 stud kit, 504-16 seals, GM performance roller lifters ACDELCO HL121, 3/8” push rods 12368081,
and the 5/16” thread x 3/8” pushrod guide plate 12562369. Started with the comp rollers, but they were very noisy, even when properly adjusted, sent them back and put the GM perf rollers in. I used the stock rocker arms. Pay attention to how the rotator eliminaters seat. The base circle on the stock cam and mine was net .006 different, so might not have needed the adjustable conversion, but did that anyway.

97 454 L29 build plans

I'm getting ready to rebuild this 454/7.4L L29 motor and want to run the mods past you guys for recommendations. I've been researching all the other build plans and results already to get me started. 1997 chevy K2500 7.4 vortec 3/4 ton long bed truck, NV4500 5spd manual trans, mainly used for...

www.gmt400.com

 

[Scottm]

Pirate, that is a fair amount of cam, 218/224 at .050. What kind of vacuum at idle do you get? What's your ecm and how does the tune manage idle?

 

[Piratehunter]

Updated part numbers above Don’t know about the vacuum pressure. Used the stock black box with a blackbear tune. Runs like a graped ape

 

[felskee]

I used the comp cam 01-415-8, 911-16 springs, 612-16 locks, 4779 rotator eliminaters, 748-16 retainers, 4514 stud kit, 504-16 seals, GM performance roller lifters ACDELCO HL121, 3/8” push rods 12368081,
and the 5/16” thread x 3/8” pushrod guide plate 12562369. Started with the comp rollers, but they were very noisy, even when properly adjusted, sent them back and put the GM perf rollers in. I used the stock rocker arms. Pay attention to how the rotator eliminaters seat. The base circle on the stock cam and mine was net .006 different, so might not have needed the adjustable conversion, but did that anyway.

97 454 L29 build plans

I'm getting ready to rebuild this 454/7.4L L29 motor and want to run the mods past you guys for recommendations. I've been researching all the other build plans and results already to get me started. 1997 chevy K2500 7.4 vortec 3/4 ton long bed truck, NV4500 5spd manual trans, mainly used for...

www.gmt400.com

did you machine the guides?
also pn for pushrods and rockers

 

[Piratehunter]

Didn’t have to machine the guides down. Reused the stock rockers. Pushrod number is above.