LM7 5.3 build question...

[riz]

what would it take to get my
lm7 5.3 up to around the 400hp range?

RIZ

[LS short box]

400 rear wheel HP or 400 crank HP?
400 crank HP. A cam, headers and a good tune.
400 rear wheel HP. A cam, headers, good heads with a bit more compression and a tune.
Pretty much any bigger cam will need better valve springs and push rods.
Depending on the size of the cam a "good" stall converter would be nice.

[cj847]

Search Richard Holdener on U tube. He has 400, 500, 600 hp tests. RWHP will be 75-100 less than engine HP.
My criticism of him is all of his test is on engine dyno. That means the engine is not running any accessories (ie no alternator, no water pump, no power steering pump, no AC, etc). For example an LQ4 is 330hp factory rated, but on his dyno it is 395-400 hp bone stock with just headers.

I built am LM7 with a cam, springs, headers, stall converter and tune. It should have been about 400hp but I never had it checked. NOTE: literally all of the gain was above 4500rpm.

[biketopia]

LS engines like RPM, don't be scared to have the power come in around 3200+, this is where a slight change in converter paired with a bigger cam can help make the combo really shine. Like said, cam, long tube, headers and good tune will get you 400hp at the crank. Some lightly ported factory heads that are milled a little to bump compression if you can run 93 octane will get you to 400 wheel. What is the use of the vehicle?

[riz]

not sure what this one is going in yet.... I just picked it up for a great price.

I have an LQ4 6.0 being built going into an 81 C-10 short box truck.

RIZ