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Hello everyone,
just wanted to share my recent build and results
it is a Darton sleeved 5.3 block 4.125x4.000
12.2:1 compression / only 18 degrees total timing on 91 didnt want to push it since it is running E most the time
.038" quench with .045 cometic head gaskets
prc 265 (upgraded stock ls7 head)
msd atomic ls7 intake (i ported and shortened runners 1.25 inches)
johnson 2126 reduced travel lifters / manley swedged 3/8 pushrods PAC 1207 springs
BTR stage 4 v2 cam (246-26X .662 lift)
deatchwerks 700cc injectors
"hellcat pump"
comp cams max lift bsr shaft rockers
holley 105mm tb
dougs 1-7/8 headers to 3" X and hooker aerochambers
mcleod rst twin disc
bottom end is Lunati crank and rods with DSS pistons. improved crank scraper and windage, melling high volume high pressure pump, katech c5r chain, trickflow underdrive balancer.
it made 630 on e85 (25 degrees total) and 596 on 91 with 18 degrees of timing (on 91) 506 tq on 91 and 525 tq on e85 (ethanol content was e70 at the time) this is in a 69 camaro with a f body t56 and a ford 9" with 35 spline axles. this is all running a holley terminator x and bowler harness for the t56. i just had it tuned this past friday and have about 100 miles on it since including an autocross event yesterday. this thing rips, the car weighs 3,072 lbs w full interior and a/c, audio etc. not a max effort build by any means but a very happy medium. it cruises in 6th at 1800 no problem and doesnt buck or lug at all... very top end happy, i'll add some pics from my phone on the next post.
thanks for reading.
Last edited by z0sicks07; Jan 19, 2026 at 03:12 AM.
You definitely have power left in the inlet pipe. That looks small for that and makes a difficult 90 into the TB.. I can tell you are space limited, but there is power there if you can figure out a bigger/better setup.
You definitely have power left in the inlet pipe. That looks small for that and makes a difficult 90 into the TB.. I can tell you are space limited, but there is power there if you can figure out a bigger/better setup.
i agree thats a 4" tube to the 105 tb it takes a shoe horn just to get that in there and the cyl head is less than 1" from the firewall
I was having some work done on a 408 magnum block a while back and saw a few engines and blocks they sleeved. I had a very good experience with them. No complaints
I see you are using the shaft rockers. Keep an eye on your valve guides - I have a very similar set up and ended up with a roller tip rocker as the LS7 guides did not like the scrub rocker once the valve spring pressures got up to like 450 pounds open. I have BR7 Brodix heads and the 1207x spring also and the Johnson lifters too cam almost identical. Engine dyno made 757 hp (6700 rpm) and 660 tq (5,000) with a 455 cubic inch and Mamo MSD. BTW Awesome looking car.
Last edited by Double06; Feb 16, 2026 at 12:35 PM.
I see you are using the shaft rockers. Keep an eye on your valve guides - I have a very similar set up and ended up with a roller tip rocker as the LS7 guides did not like the scrub rocker once the valve spring pressures got up to like 450 pounds open. I have BR7 Brodix heads and the 1207x spring also and the Johnson lifters too cam almost identical. Engine dyno made 757 hp (6700 rpm) and 660 tq (5,000) with a 455 cubic inch and Mamo MSD. BTW Awesome looking car.
thanks for the heads up, ill definitely keep a close eye on it!
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