['70basketcase]

Refreshing my LS7 454 , keeping mostly stock bottom end except I milled down the solid domes to 10.2 SCR with h Brodix RR 270 ovals 110cc head, should use Air Gap RPM intake and 850 DP.

But I may repurpose the heads and intake for another build in a few years and may install a set of ported 2.19, 1.88 781s and Qjet RPM intake after.

Cam is small but I like oldschool cams, its a UD 402A3 Solid lifter with 160 dur @.200 so its a street friendly cam but still some intensity to it.

To take advantage of the good flowing 270 Brodix RR ovals at higher lift, I plan on running 1.8 HS rockers VS 1.7.

Ive done that numerous times on race engines without adverse effects ( actually reduced wear at the lifter) but what about street only use? Anyone with real 1.8 rockers experience on the street with SFT cams?

Please dont tell me about wiping lobes with SFTs

Peter

 

[mrpaticular]

SFT here.
For street only I would leave it alone. If you do move up you should recheck pushrod length and coil bind just for piece of mind.
Rick

 

[-SS454-]

What are the full specs of the camshaft now?

The Brodix RR270 heads basically plateau around .600 lift on the intake, and like .550 on the exhaust.

 

[David Bates]

What are the full specs of the camshaft now?

The Brodix RR270 heads basically plateau around .600 lift on the intake, and like .550 on the exhaust.

Current Lunati p/n 30110513: Gross Lift .586"/.600", Duration @ 0.050" Lift 243°/251°, Advertised Duration 276°/284°, LSA 110°, ICL 104°, 0.026"/0.030", 2400-6800RPM range.

 

[-SS454-]

Current Lunati p/n 30110513: Gross Lift .586"/.600", Duration @ 0.050" Lift 243°/251°, Advertised Duration 276°/284°, LSA 110°, ICL 104°, 0.026"/0.030", 2400-6800RPM range.

I don't think going to a 1.8 rocker would be worth it, at least not on the exhaust side. Putting it on the intake side only narrows the split a bit, and the RR270s like a large split between intake and exhaust.

 

['70basketcase]

I've used that cam in 454s with 049s or 781s many times, probably my fav cam in a stick shifted iron headed street BBC. I have the Brodix RR 270s sitting on the shelf and would like to use em, but since they flow better than most home ported irons , I thought about the 1.8s since I have to get new push rods and rockers anyway.

As for coil bind the heads are good for .700 lift, this is really a "smallish" cam even with 1.8s.

Peter

 

[427L88]

Yeah, I LOVE it too! ( and not you and Mr Bates). My thoughts, that cam is pretty darn intense the way UD ground mine, so.... I wouldnt mess with it. Have you run lash down to 21-22 yet? THATS FUN! ( Harold told me .021 is as tight as he'd recommend for the "100,00 mile" service life.Tighter may not let the ex valve cool down as much ) If fact, with my enduro runs ( long highway travel) he preferred it down that tight. Really quiet @ .022", almost sounds like gentle piston noise.

Anyway, that's the "vernier dial in" effect I'd focus on, lash.

 

['70basketcase]

427L88 I hear you, I have played with lash before even went tighter than .021 on that cam with more strip oriented car where longevity isn't an absolute priority. I was going to run ported 781s and Qjet on it but I just wanted to maximize the cam if I end up using the Brodix heads and 850DP

 

[427L88]

, probably my fav cam in a stick shifted iron headed street BBC.

Peter, dare I say that's only because you've never tried it sucking air through properly prepped alloy heads! The 3rd iteration of the L88 used that cam , set in+6 as per UDH working a fresh set of 074 GM alloys. HOLY That's when it whacked my buds 509 Camaro at the track. GREAT CAM, regardless of metal! Those heads were drama prone due to porousity, but DANG! they made power.

PS, on the 781s on a chiily but salt free winters day, the clutch stuck on my first real ROMP, and it must have bounced off 8000 before it went BANG! and grabbed. While slightly flustered as to why, that lingering "sound track" of that lil 427 sucking air at high revs was near priceless. Overrevving with 1135 cfm of tripower on top comes WAY too fast! That cam runs GOOD and stable. ( Isky 8005a + Ti retainers)

And again, the cam's designer Mr Brookshire told me that .022 was PREFERRED for my long trips @ 3000 rpms to the various Chevelle shows, so dont fret. The "banging" if I went past the , what 026/028 setting was more of a concern. Oddly the old cam, a Crane commander hated being tight, although any trace of solid cam tapping disappeared. ( it may have been TOO tight), but loosened up, with quicker valve action, WHOA!

Sorry for derailing the thread here, I miss my UD 276/284 ! Being raced this summer at a track near me!

 

['70basketcase]

Yeah I like the rev happy nature of that cam the LS7 always been shifted at 7000+ , I also run a steel flywheel and Blowproof bell because I like my legs, The 402A3 also sounds proper in old BBC too. Im oldschool , cant help it. lol

 

[427L88]

ROCK ON!

 

[mrpaticular]

I run my lash at 24 and 26 and use the eoic go no go method. Very time consuming.
Rick

 

['70basketcase]

I find lash setting time somewhat zen

 

[427L88]

that's where i was cold lashing, other that the hot lash check to know the hot/cold delta.

 

[mrpaticular]

I find lash setting time somewhat zen

Same here but the go no go you are constantly changing feeler gauges. Last summer I dropped one down the hole in the top of the head into the lifter galley. Now I plug all holes with a paper towel.
Rick