Today I completely tore down my lt 93 LT1. Everything looks good internally so now its time to spend some hard earned $$. I've been debating between a 383 & 355, and I believe I'm going to go with the 355 due to my $$ flow and the possibility of adding a turbo down the road. I would like to see 400-450 at the rear wheels and the ability to take a 150 shot. Here is what I'm going to get first for sure...

350 Scat Pro Comp Series 9000 Crankshaft
Eagle ESP 3D 4340 H-Beam Rods 5.7"
Wiseco Forged Pistons (flat, dish, domed, help me out here)

I'm really a cam dummy, I dont really know what I need but im sure ill have to get one size now, and another if I ever decide to go with a turbo. I know there is a lot of other things I need to make the 450hp and thats what I'm on here asking for you guys to help. I feel better asking advice then to try to experiment and wasting $$$. Also I'm going to go with new push rods and rockers. Any suggestions on anything here. Here is your chance to build a motor with someone else's money.

 

if your going turbo, they have forced induction camshafts that fit the specs to get the most power out of the engine.

 

450 NA will be impossible or close to it with a turbo motor due to the low compression you will need unless yoy go very radical in cam and spin it high (pointless on turbo motor).

If you build it for nitrous, thats not an issue. Build it 12:1 CR (maybe pop up pistons, depends on many issues, talk to your engine builder) Cam in range of 240/250 hydro roller cam if you want mostly NA power, and a set of heads flowing 280/220+ and you should be there or very close.

The above cam is a good NA choice. If you want a purely n20 motor, i think you want to widen your LSA and add some exhaust duration, but im not too much into the n20 stuff, so thats better left to someone else.

Ever thought about going solid roller with the cam? Could run similiar duration, but crank up the ramp rates, get more lift, and be more driveable with better vaccuum etc.

Pushrods = anything hardened will do. Im running comp hi tech (120 ish a set) and love them,

Rockers = comp pro mag, non self aligning hands down

dont forget guideplates, genuine GM suggested. Combo sells them at a good price

But... this is your motor not mine What kind of duty is this, everyday DD, street/strip, track queen. What kind of RPMS and driveability are you looking for etc. Fill us in

 

I should of gave a little more info on what I need it to do, sry. Well first off it will be a DD. Right now I only drive at an adv. of 6-10 miles a day, but it will need to make those occasional 40 mile trips. Here is the thing, my current car which is a 95 Camaro 3.4. I bought a friends wrecked 93 z28 with this motor. So yes I'm doing the whole swap thing. Both cars are an automatic, so no problems there exept chosing what stall I'll need when I get this motor built. I dont really do a lot of drag racing but I'm sure I will when I have this motor built. I just wat to be able to hit the gas and snap my head off And I'm not going to be constatly throwing nos into the motor, I just want it there in case of emergancy's. As far as rpms go I dont really know what a LT1 will run at because my 6 banger tachs 2000 at 55-60 mph. I'm sure the LT1 will be lower, but here I live I do have to do a lot of highway driving. Usually between 35-65 mph. I guess I just want a car with over all power thru the rpm range. But I'm up for any changes (gearing ect. ect.)

 

now is an important time for you to decided exactly what route you choose to go with this. Since you want to do NA for now with some N2O usage i would say to have the heads you will be useing to flow well but at a reasonable/cheap price. Figure some decently worked stock heads. Now you have decent HP+N2O when you need it. Now when you decide to go FI you have some money for some well done aftermarket heads and they can be specificaly done for your application (bigger chambers, ect.) with a nicely matched cam to complement this.
I find this route more reasonable to me becuase it leaves the professionals to do the work they do best; leaving you with a stout, dependable reasourse of HP.

Sorry about the rant but I have gone through a similar situation and i wanted to make it clear that you have to have your ultimate goals in line with the things you do to the engine now. There are big differences in NA and FI when high power is concerned. This is all being said from my money concious perspective.

-Fran

 

There is already one person on this board making 450rwhp. I think he had a cam from Joe and I forgot who did his heads.

 

Probably Lloyd...

 

If you get good heads, say lloyds for example, and tell Joe overton you want to make 450rwhp, hell do it no problem, but hell call you an idiot. Now if you tell him you want your car to be fast, it might only make 400rwhp, maybe less. Peak hp is bragging rights only, meaningless in the real world, never heard of dynoracing have you?

You want the most power under the curve. For example, you could get a sudden spike and it jumps from 380rwhp up to 450rwhp, well the dyno sheet says max hp, 450, but it doesnt mean anything.

Id shoot for 400rwhp, with a small CI, stock casting head LT1, I wouldnt hope for much more than that, if it is a GOOD motor, not a dynoqueen.

 

That's a good point jonaddis84. I would much rather have power all thru the bands then to have it all at say 3500rpm or what ever. This is an automatic so I really need to keep it in mind. I was up all night sick so I took off work today, im going to set here and plot exactly what im looking 4 and what i need to achieve that goal. And I also agree with ya Tony, if I want to go FI I can get me some real heads 4 that application with the right cam, and I should be right there. Because I know when its built I'm going to want it done down the road.

 

If you use a low-compression motor built for a turbo, you're going to have a hard time squeezing NA HP out of it.

If you're going from a 3.4L to a LT1, why even worry about all of that insanity?

Build a nice stock bottom-end heads/cam car, with a meaty hyd or solid roller and some heads from Phil (SkarodoM) (www.advancedinduction.com)

Mike

 

It was from Eric Bradby "Tin Shed Racing", and his board name is 97 WS6 T/A Conv

 

Yep, and that is a badass car too. I've got his old 306 cam in my LT1 now.

Another friend of mine just went with Lloyd Elliot heads for his stock 96 LT1, they look damn good too. I tried to get him to go with Joe and Eric, but he is kinda stubborn. I told him to go with what was proven to work. Quickshot is pushing 430+ and Gary is 452. Two locals with combos that are proven.

 

You need to remember 450rwhp is around 550 flywheel.My355 made 465 with a junk clutch .Going to the dyno this weekend with a new clutch,I broke down and bought a street twin,I hope its worth the money.

 

Weight is a major key in a motor in my opiion. I got the Eagle SIR LW 6.0'' Rods. I also went with wiesco pistons flat tops at 10.4:1 cr. Ill prolly run a LW crank as well. My engine is in the same goal as yours a daily driver. Plus i plan to run nitrous. I was thinking a 230/236 cam or 306. Just whatever you want.