Sauced

Alright so i am finaly rebuilding my 96z28s Lt1. Im buying a forged scat stroker kit and having my heads p/p by elliot. Im also going to have them set me up with a cam. The goal is 380rwhp. I need to know if i need new rocker arms and springs/lifters? If so recomendations would be great. Also want suggestions on headers .Thanks for any input.

grabbem88

If Elliot does your heads and cam he will match springs to the cam

Sauced

Perfect thankyou i was unawhare of that

Chimera96

Lloyds heads would come with springs. I assume he could also sell you RR.

Comp Ultra Pro Mags NSA RR

Might want to consider .080 thick wall PR. You would want hardened and run guide plates

Lloyd can likely set you up with all

87Aerocoupe

Also get ebay stainless long tube headers and a 58mm tb, 42# INJECTORS,I'd also look at getting an aftermarket 6 qt oilpan. This combo should make 410+ rwhp with a good tune from PCM4LESS.

Sauced

Thanks for the reply. Will a larger oil pan effect my oil pressure?? When i bought the car it seemed to always have lowish oil pressure.. i heard that was normal for the lt1s but has always bothered me. Anything i can do to make sure my oil pressure is better? Is it necessary?

Thanks for any input!

Injuneer

As an alternative thought.... you say your goal is 380 RWHP. You don't need a stroker for that HP level. You can make that kind of power with a 350-355 CI engine.

I would stick with the stock pan and stock pump. I run a stock pan on an 800 HP build, buddy of mine ran one on an 1,125 HP, 8,000 RPM forced induction build. But no, a larger oil pan does not reduce oil pressure. Oil pressure is determined in part by the clearances in the engine oil system, not the volume of the oil pan. A newly built engine should have good oil pressure. There is nothing inherent to the LT1 engine design that causes low oil pressure. Again, I run a blueprinted stock pump (but some of the newer GM castings may not be the best), with an 80 psi "white" spring. That gives you the pressure you need at higher RPM. The critical part in the oil system is replacing the stock plastic oil drive retainer with an aftermarket metal retainer.

I would also suggest that if you really only want 380 RWHP, you are barely over 32 #/HR injectors (assuming you're putting the power through an auto trans). I would use 36 #/HR injectors. They will be adequate for 500 HP at the flywheel.

A 52mm throttle body is more than adequate. GM used the 48mm throttle body on their 502 CI EFI crate engine. The shop that built my engine was able to show me with the engine on an engine dyno, fully instrumented for air flow, that I didn't need any more than a 52mm TB at the 500 (normally aspirated) flywheel HP level. The engine peaked air flow with the 58mm TB only 77% open. Increasing the flow area did nothing... the engine was getting all the air it could consume.

Sauced

Awesome stuff to know thanks!
Well 380 rwhp is the minimum hopefully hahah 400 of corse would be better!

And i know i can reach that with a 355 i just naturally went straight to the 383 stroke buttt am still at the point where i could change my gameplan to a 355


Any pros/cons of the two? I know the 355 will be able to rev higher and the 383 will have more torque but any other advantages/ disadvantages to consider?

This will be a street car and ocasionaly taken to the 1/4 mile track for fun

Also might add in i have the 6 speed manuel
Thanks for the help!

Injuneer

With the T56 it's even easier if you state your goal in terms of RWHP. I measured the actual losses through a McLeod Street Twin/T56/3" chrome moly driveshaft/12-bolt rear axle at a shade under 13%. 486 flywheel = 425 RWHP

Personally, I would focus on flywheel HP/torque. When I went to the TH400 I lost 35 HP at the rear wheels, due to a shade under 20% drivetrain loss. 486 flywheel = 390 RWHP. But the car was just as fast, with the right combination of stall speed and rear axle ratio.

It not all about peak HP at the rear wheels. For a street car, you want "area under the curve"..... good torque down low and over a wide range of RPM, rather than just peak HP up high.

Sauced

Yes to pull better through a wider span if the rpms right?

In that case the 383 would make that nicer curve right?
While the 355 generaly pulls mostly uptop in the higher rpms

Sauced

Yes to pull better through a wider span if the rpms right?

In that case the 383 would make that nicer curve right?
While the 355 generaly pulls mostly uptop in the higher rpms

Sorry If my questions have obviouse answers i am still a rookie

Thanks for the help