So i know there's a few posts like this one but I would like some advice and tips on my specific build.
I am building a gen 1 350 chevy that i plan to turbo. Im hoping for 600 horsepower to the rear wheels with a lt1 t-56. Its going in my 1980 GMC Sierra. I want it to be pretty driveable but I don't plan on it being a daily driver

Im still in the early stages of my build so any and all advice is appreciated. Im starting with a '74, 4 bolt main 010 block, .030" over and it was decked about .010". I have a pair of 76cc cast heads with 1.94/1.6 stainless steel valves. With a MLS head gasket this puts my CR around 7.8:1
Forged pistons with a 20.4cc dish and heavy duty chevy connecting rods. I also have a stock crank which i'm debating whether or not to use. Im considering investing in a forged scat crank. Any advice on what i should do?
Im going to keep the engine carburated and plan on using a Demon 750 blow-thru carb. Not sure what ignition system i should use yet.
I haven't bought a turbo yet. Do you guys know anything about those ebay turbo kits? are they junk or will they do what they claim? My other choice would be to find a used turbo
I could also use some advice on a cam to use, oil pump, bearing clearances etc. Any advice helps at this point.

Thanks in advance!

 

You know, the best thing to do is decide how you want to make the combination to make the power and the fuel you will use primarily. My personal favorite ( emphasis on personal ) is strong NA motor with a low boost turbo for gasoline. Put together a strong bottom with great heads, cam and induction so that she runs like a beast without boost, then add just enough boost to do the job. This way she'll live a long time.

On the other hand, there's the mild NA/high boost combination. Build for strength, low rpm ( 6000 rpms and under ). Because of the high pressure and lower rpm, get the tune wrong and you push gaskets and break stuff. Most civilized to drive, emphasis on torque, great for heavy vehicles, smooth to moderate idle.

The main thing is to build the combination to be as detonation resistant as possible. With modern ignition and boost retard you can run more compression than 7.8 to 1 static with iron heads.

Take a look at the LS engine. It has awesome heads, fast burn chambers, free flow induction and exhaust and a 6 bolt bottom. Take those principles and apply them to your Gen I ( as far as having the top end is concerned )

 

This thread may help you decide on a few of your questions.
https://www.theturboforums.com/thre...enade-part-2-to-come?highlight=grenade figure

Warning though, it's a HUGE read!

 

I would definitely consider switching heads. The ones you have are probably about the lowest performance heads there are for a small block Chevy. With your dished pistons, a good set of aluminum heads with 64~68 cc chambers would make more sense. Smaller, better chambers make more power, and do so more efficiently, and the aluminum makes it more detonation resistant. If you do read the Grenade thread above, IIRC, each significant power increase came with the addition of better heads.

 

Definitely step up the heads. Those old truck type castings won't do you any favors at all. Personally I haven't used the Demon blow through but I know a couple of people who have and were pretty disappointed by it. One went with a hangar18 DIY holley and one with a CSu and both were way happier.

I have some of the parts you'll need from swapping to an FI build. Let me know if you need anything. May help sifting through a ton of options.

 

My carb is a Demon 750 I converted to E85 and blow-through myself, works pretty good so far.....

 

It inspired me too!
Still haven't finished my car but I'm probably 75% done. I had 2 sbc' laying around and ended up building the best motor I could by combining the best parts from each motor. By "best" I mean least shit!

So my combo as ended up being a 2 bolt 357cui, scat 9000 crank, scat I-beams, old trw replacement pistons(forged), Summit 1103 equivelant cam, edelbrock performer rpm heads 185cc/70cc , torker intake, Horsepower Innovations blow through e85 carb, EV hat, 83mm turbine BW S480, China 60mm gate, 50mm bov, msd 6530 and hvac11 coil, th400, 2500 converter, 3.55 gears(want to change to 3.08)

Only performance goals are to kill tires from a roll! Lol

 

Some progress pics of mine...

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So it looks like, according to the GRENADE SCALE, you have a 1400hp combo! Go for it! She's gonna fly! 8 seconds for sure!

Gonna run my old girl on E85 on the street and spec E85 or E100 when it's time for the money runs. On gasoline she'll be too touchy. Besides 35 to 40 psi boost you can't mess around.

 

You guys are crazy you drive on the wrong side silly.. That's awesome

 

So i ended up spending the money on a forged 4340 crank and h beam rods. Decided to buy ARP main bolts as well. My goal is 600 horse to the wheels with a t56 transmission and id guess somewhere around 12 pounds of boost will be where i want to be. Its going to be intercooled and i plan on running 93 octane. Any other suggestions on budget heads? The set i have is completely redone, bigger valves and low compression. Also any other suggestions on carbs and ignition systems?

 

Well if carbureted I would suggest going with the MSD 6AL BTM kit they give you everything you need for around $900, I have the whole kit minus the coil, that I would sell for much cheaper, everything is new in the box.

As far as the carb it seems that CSU and C&S are the ones that have there carbs really dialed in to work properly, definitely want a boost referenced fuel pressure regulator otherwise you starve your carb under boost. I also have one of those if you were interested, its an aeromotive 13204.

Basically I got talked into going fuel injection after already buying the whole setup for carbed.

Definitely think you should go with aluminum heads, and if you can afford it Inconel exhaust valves for some insurance, probably not a big deal at 12 psi but if you wanted more power later it would be good insurance.

I don't know the latest and greatest formula for gapping your rings for boost but be sure to look it up and file your rings!

Cam goes in straight up

Have fun with your project!

 

For budget heads I would try White performance, procomp heads, would probably want to upgrade the exhaust valves

I think you mentioned something about ebay turbo kits, and I would say the only one worth bothering with is the cxracing kit for 60's chevys about $1800 and doesn't look perfect but its looks way better than anything else on ebay and would probably only require a few mods for your application, they are cheap turbos and cheap waste gates but sometimes the budget calls for cheap...