Hey guys. I've been looking at this topic for a while and been asking questions already here and there, but I am still pretty clueless what I should get.

I am building a car for road racing and some cruising (not daily driver). So far my drivetrain consists of SPEC Stage 3 clutch, T56 out of 97, 3" Al driveshaft and 4.10 10-bolt. Engine is the missing piece right now. Will go with 2055 headers.

I am thinking of getting a short block (with decent parts) and selecting my own cam/heads/intake. This is where I need help picking parts and sources. Most common question here would be "it only depends on how much you are willing to spend" and I agree with that. So to start the discussion, let's start at $6000 (if needed, I can go comfortably go as high as 8 grand). What would you do, given this target price?

Right now the only things I am considering: 1) Holley 750cfm double pumper. 2) I want power band go to ~6000 rpm, maybe even 6500 rpm if I can keep the car streetable.

There are a lot more questions, but for now, what do you guys think should go with?

 

I would build an L98 with an Lt4 hot cam, Performer RPM Aluminum Heads, and for road racing purposes I would make it fuel injected and use the holley stealth ram system(Dont ask me why, but when I think of road racing I think fuel injection). but if your going carb I would use the RPM air gap intake. This setup will easily spin to 6000 and will make at least 400 hp. Good Luck.

 

8k? Do the LS1 setup. The engine is all aluminum (much lighter, so better weight distribution between front/back), can pull higher octanes, already a stout engine from the factory. You'll get a 6-speed from that too, but the LT1 T56 wont match up.

I'm sure whatever you end up doing you'll have fun in the end

 

Id get a 350 or 383, forged bottom end, lunaty cam, 1 3/4 short hedders and LT1 intake.

HYDRAULIC ROLLER, Fair idle. Good for high performance street use.
2000-6400
298°286°
227°234° @50
478".480"

That cam is also compatible with blowers & nitrous.

 

LS1 or LS2

 

Blown or TT LS1.

 

thanks for the responses, guys. Apparently LS1 (2) is a favorite for a lot of people. The reason I didn't want to go with that block is 1) not sure if you can put a carb on it and 2) since LS1 is so new and different from previous gens, most parts for that engine would be more expensive just for that reason whereas older 350 is pretty common.

Without getting into arguments which way(carb vs. efi) is better , for this car carb is something that I want to go with.

I want to go with a 350 that will bolt up to my LT1 T56. So given this, I figured either crate or short block and go from there. What I didn't like about crate motor is that you are pretty much stuck with what they select for you. ZZ4 tops out around 5200.

That leaves buying a short block and going from there. Now question of the day: what should I look for in a short block? As I understand "forged" means good, right? What about ZZ4 short block? I've also read you could go with a chrome-moly (sp) crankshaft, but that stuff can get rather expensive rather quickly. What advantage does that give you?

 

k, just read that Hypereutectic pistons are cast. that's not good, is it? - I want to leave open the idea of adding a turbo or supercharger at a later time.

 

A hyper piston isnt as good as forged that is for sure.

You can carb an LS1 here is the link :

http://www.edelbrock.com/automotive/...manifolds.html

Scroll about halfway down and there is a picture and a description. It comes with an MSD setup to run the stock ignition, so no worries on that. Looks like a cool setup, something I am going to try someday. I havent seen any dyno numbers with it yet, but I am sure it will perform impressively.

 

I saw a deal about this on TV one day. They didn't lose any power by going to carb, they may have even gained a little but I can't remember for sure. I think it would be a great way to avoid the wire mess involved with an LS1 swap.

 

GM Performance parts 385,just bolt it right in carb and all

Or dis one
http://www.sallee-chevrolet.com/Chev...s/safrzz4.html

 

Start from scratch....350 block bored .030 over, forged stroker crank, forged rods, forged pistons, a good set of alum heads (better heat rejection), intake manifold and cam (flat or roller?) matched to your desired power band. Then all of the "little" things...oil pump, timing chain, rockers (I would go SS or CM rollers), push rods...gaskets.
As long as you don't go hog wild you'll have a VERY stout engine for less than the 8k max you stated.

By starting from scratch, you'll know exactly what's in your engine and how strong it is.

 

well, considering I never planned on LS1 and already have T56 and $500 clutch for non-LS1 engine, I'm probably going to stick with the original plan.

Morley, I am leaning towards what you are proposing. The only thing I want to start off with a short block so I don't have to mess with assembling that stuff and all the clearances/tolerances involved with that.

The question becomes where can I find a short block with all forged bottom end? Anyone know of a good place that sells quality parts?

Actually I am still not sure about pistons. I read some place that hyper pistons are lighter than forged and for most applications (up to 500hp) would work better? Is that still true or are the forged pistons they make now would be just as light? -- if that's the case maybe ZZ4 short block would not be a bad choice.

 

They can make forged pistons that are really light now around 300grams. That is way lighter then you could get with a casting, since you can't make them as complicated.

I'd go forged though its only $100 or so more for some Speedpro coated and forged pistons.

http://www.wheelermotorsports.com/en...hortblock.html

 

Piston type convention:

"Cast" - pistons formed by pouring molten aluminum into a mold to form the basic piston shape. The aluminum alloy used has a silicon content at the eutectic point (the percentage of silicon at which the metal goes from solid to liquid with increased temperature without any solid/liquid "slury" phase).

"Forged" - pistons formed by forcing the aluminum unmolten into shape using forms. The metal grains are deformed in a "flowing" fashion, increasing strength. Uses a different aluminum alloy than cast pistons.

"Hypereutectic" - pistons formed by pouring molten aluminum into a mold to form the basic piston shape. The aluminum alloy used has a silicon content above the eutectic point (hence, the "hyper", which means "above" or "over"), which gives the material more strength - but less ductility. The casting process used keeps the metal completely molten until it has filled the mold.

Casting forming methods are cheaper to do than forged processes. It is the improvement in the casting method that has allowed the use of the stronger hypereutectic aluminum alloys in the casting process, producing a stronger product than older conventional cast alloy pistons, at a cost close to the conventially cast pistons. It is the reduced ductility of the hypereutectic pistons that makes them less desireable than cast or forged in power adder applications - detonation is more common in those situations, and detonation is a shock event - reduced ductility reduces the material's ability to withstand shock.

 

so in short the answer is "yes"

Ok, being a smart *** a little. five7kid, always liked your answers. And for everybody here just want to say you guys rock. I hope you don't find posts like this annoying (kinda a little repetitive), but I am learning a lot here and unfortunately, you can probably tell, I am not even close to being done.

Thanks a lot everyone.

Looks like I want to look for forged bottom end. Now next question will become cam/heads. I know with cam you make a spec and then find a cam. But with heads, I think you find the head and then have to look for its specs. Is there a good resource that lists what's available for us? I would probably be looking at aluminum ones.

 

Can we assume that the $6000-8000 budget is for the engine only, and that you will not be using a power-adder?

If so, then hypereutectic pistons would be fine. SDPC has a Fastburn 385 w/Hot Cam that puts out 430 ponies for $5000. Accessorizing that would put you right at budget.

Or, find a 350 block, get a 383 stroker kit, use Fastburn or AFR heads, get it completed for about the same, perhaps slightly more, money.

 

Yes, the budget is for the engine only, no power adders. For now I just want to build this thing n/a and see what I get out of it.

ME Leigh, I took a look at that website, they sure have some cool things there. This this combo caught my eye. The only thing that's weird is that it says 355, but crank has a stroke of 3.750, I did the math and that adds up to 383 (I think that's the mod five7kid was talking about) Also it comes with a comp cam that has no specs, I can only assume that you can tell them your own specs, maybe? And they come in either 5.700 or 6.000 rod length. What effect does that length diff have on the engine? With 64cc heads, this engine would be about 9.5 compression (I think). Would that be good for pump gas?

five7kid, I looked at the Fastburn 385 and it looks pretty decent. Since I am not buying the engine for a while (still have to rebuild things, paint a car and put suspension back on), I want to do some looking and asking around and come up with my own optimal parts list and then see how close that would match one of the crate engines. If it is relatively close I may decide to go that route, but otherwise, I'd like to stick with things I choose.

The reason I want to stay away from hyper pistons is 1) may do power adder later and 2) they don't like detonations as much. if I do have few detonations for one reason or another, at least it is nice to know forged pistons would hold up better.

 

Nice thing about a crate engine is that they come with a warranty and all the high price machine work is already done and there balanced
I just recently spent 1500 just on machine work alone for my 383 and yes it still hurts

 

From spdc2000 website, ZZ4 crate engine page:
I thought only replacement engines had 1 or 2 year warranty, not performance ones.

I know there is machine work involved. That's why I want to get an assembled short block since at that point (as far as I knew) all of the machining, decking and balancing was done. Then I would assemble the rest.

 

You are correct, get a good shortblock and add some good heads, and a good cam and you will have a good engine.

 

no warranty,well that sucks.

Makes sense though i guess when your buying performance they no your gonna stand on it from time to time

 

I just pulled a calculus book that hasn't seen the light of day (or table lamp) for the last 5 years and decided to figure out the effect rod length has on the engine. And the funny thing is that I actually did

I have an excel spreadsheet that has all the formulas, but for now will post the image of the chart. [at some point I probably should make the thing available to everyone so they can play around with the numbers]

Basically it looks like piston velocity is always the greatest at 65* ATDC. Shorter rod will have higher velocity at 65*, but speed will drop faster as it approaches BDC. Longer rod will have lower velocity at 65* but later on it will be traveling faster as it approaches BDC.

Looks like longer rod is better because between 65* and 180* it has more area under the piston speed, so I would guess it should suck more air in than shorter rod would.

so any of this make sense?

 

oh yeah, piston position above crankshaft (I am not fixing the typo in the gif ) is a set of curves at the top. piston speed are the bottom curves (negative because piston is moving down)

 

if I had it to do all over==well you can have my 8000 dollar 327 for 5200 dollars, and I would go get a 540 short block for 4000 and add a dicent set of heads a small call red line of 5000rpm and a 850 holley 4150 for way more streetable hp and tork

just my 2 cents

later and
GB

rick

 

go ls1 if you really think you want an ls2, just get the ls1 outta the z06 basically same engine, only it will be a little cheaper to get a hold of right now and gotta go t-56 look on ebay you can find these things all day long with the tranny and computer for less then 8k

 

I really appreciate everyone's advice here, but I am really not looking for what engine to build. I already know what I am building. I am not looking for LS1 (or LS2), nor am I looking for anything lower/bigger than SBC 350. Nor am I looking at an EFI setup.

What I want to do is start with a pre-LS1 350 short block and build it up with best combination of parts that I can come up with and then top it off with holley carb (probably 750). What I was hoping from the thread is to discuss what this combination might be.

Right now it looks like I'll get an all forged, pre-assembled bottom end. Next question I am looking at is where do I get the list of available heads for a 350? People talk about heads here and there, but how do they decide which ones they'll go with?

 

There are a lot of different factors people go on, probably first and foremost is price vs the performance they are looking for.
You need to know some things about your eingine build in advance, desired operating RPM, cam, induction, compression ratio, what type of fuel (89 or 92 octane or racing fuels), Perimeter or center bolt valve covers, the list goes on.

 

yep, this is why I am here. I know head selection depends on all that. What I don't get is how it depends on all that. That's why I am turning for help to you guys so that someone could explain how all these thing effect head selection. Let's take what I have so far and explore that.

bottom end: All forged parts. flat top pistons. 350 bored over .030" inches with 3.750 stroke crank (according to my math that's 383) I was originally thinking of building a 350ci engine and shooting for 400 hp but for extra 100 bucks it would seem to be a shame not to go with 383 (although don't think rear end is going to like that too well)

price vs the performance: Complete engine roughly at $6000. Will go higher if price justifies the added value (comfortably up to $8000) vs. good performance. I would expect at least 450 hp out of this thing, hopefully a little more. reasonable?

desired operating RPM: 3000 to 6500 rpm. Unless this will kill drivability. I don't mind downshifting, but I would still like it to pull somewhat under 2000 rpm. If that's not possible, then hopefully 2500 to 6000.

cam: I figured match the cam to the heads and rpm since it is much easier to find a cam with desired specs. If I had to pick one now, how about solid roller 236/238 110 LSA

induction: not sure what this is. carb? In that case, Holley 750 double pumper

compression ratio: I think with 64cc heads that short block from wheeler motor sports would give something along the lines of 9.5. No one confirmed that, but does that sound right?

what type of fuel (89 or 92 octane or racing fuels): it should be streetable, if I can get it to work with 89 that would be a bonus, 92 is fine. Just for street would 89 be fine as long as you don't do any WOT driving? Reasons I want to look at aluminum heads are 1) lighter and 2) hopefully would run a little cooler to help keep detonations down.

Perimeter or center bolt valve covers: what is the difference? (i.e. advantages/disadvantages, not "one has a bolt in the center") Which one would be better?

the list goes on: what else you got?

 

Sarting with your C.I.D. of 383, carb induction and RPM of 6500, you want a head with 195+cc runners to feed it air.
9.5:1 compression will be very streetable on pump gas with either iron or aluminum heads. If you are set on aluminum heads, look into either CnC Trickflows or AFR's, both are proven performers and will flow more than enough for your application. With the heads comes the decision on valve cover type, center bolts are much less prone to leaking but require narrow, self aligning rockers and you are somewhat limited on your chioce of valve covers. With perimeter bolt covers you can use the more widely available rockers and covers (center bolts were on the factory roller engines).
For daily driving I would personally go with hydraulic roller cam/lifters (others will disagree) it is quieter and requires less maintenance.

Going on your basic engine specs, desktop dyno puts you at a max HP of 449 @ 6000 RPM Max torque 428 @ 4500-5000 RPM.
These figures are at the crank using AFR 190 heads. A pretty respectable engine.

With CNC trickflows 434 HP @ 6000 419 torque @ 4500-5000