LVZ2881

iTrader: (4)

My previous experience building a motor was 15 years ago, building an old school 355 SBC for my '79 Z28. Just bought this TA a month ago, drove it for less than 100 miles and it looks like I spun a bearing. Still doing some diagnosis, but considering the metal in the oil im seeing in the heads, thats what it looks like. Having never really played with an LT1 other than bolt on stuff, I could really use some expert advice from some people who may have already built what I'm looking for.

Here's what I'd like to accomplish with the new motor. The car is my DD.
I'd like to wake up Friday morning, jump in the car to go to work, turn the A/C on, and have it fire up like a normal car, and actually pass a few gas stations on the way there. After Work, go to the track and run mid-high 12's (once the rear is upgraded with 4.10's), and be able to keep up with the newer LSx, 5.0 and Euro stuff. On Saturday, go pass emissions to register the car with no hassles, and then go auto-X.

My questions are these:
1. Can this be accomplished with a H/C/I 355?? I'm looking at going with this cam from LE: 223/230 .565/.565 112 LSA. - 1700-6100 RPM as he states this is the largest Emissions friendly cam he recommends, and using this in conjunction with some LE1 heads, possibly upgraded to the 2.0/1.6 valves, or the equivelant AI heads, and a ported intake. I would also uprade the rod bolts and to forged pistons. This is all provided the crank/rods in my short block are good.

2. option 2 is the 383 shortblock from either Clayton Racing or Golen.
How reliable are the Scat Cast Cranks?? I would then put the above H/C/I on this..

3. Also, what are the advantages to a 6" rod, and is the power increase worth the cost?


I would like to make 425-450 HP at the crank as I think this would accomplish my goals...
I already have Pacesetter emissions legal Lt's that need to be installed, plus the LS airbox stuff, and a 52mm TB.
I'm assuming an upgrade to a 58TB and larger injectors would also be required?
any suggestions??

OddballLt1

iTrader: (1)

Honestly, I would clean up and reuse your stock internals. That assumes that your block doesnt need a bore & Hone. Secondly, to run the 12s is very easy and doesnt require swapping heads or a cam. You can run that with Lt's, gears, CAI and Drs.

Powerwise to hit 420-450 at the crank, would be full boltons and a mild cam.

01fxst

I was in a similar boat. When I did the math it wasn't much more for a Golen street strip 383. It's been working out great. That would be my recommendation.

LVZ2881

iTrader: (4)

A golen 383 is something I'm looking into..I'm going to call a local machine shop tomorrow to start looking into the cost of having mine re-done and compare it.

ebeard

It's nice to see somebody intelligently ask for advice for a change. You even CLEAR goals for the car. As far as power goes, a H/C/I set up should be just what you are looking for and make power very close to your goals. AI or LE will be able to hook you up with a set up that will pass smog.

As far as the internals go, if you are going to do forged pistons you might as well do rods as well with arp bolts of course. They are going to be the weak link.

Most people will tell you that a 58mm TB isn't necessary. You should be able to easily meet your goals with stock throttle blades no problem.

If you did a good 355 with the forged rods/pistons and a good tune you would be in good shape for low 12's. Plus you would have a good candidate for nitrous when Ford starts boosting these new 5.0's

LVZ2881

iTrader: (4)

Do you have a recommendation on rods, brand/type, I or H beam?

ebeard

I just did a stock rebuild with a baby cam on my motor. Its been awhile since i've looked at that stuff. Forged rod/piston and stock crank is what I would do. As for brand and I or H beam IDK

RamAir95TA

iTrader: (2)

1.) Absolutely. One would probably say it's EASY. You can achieve the same goals (A/C, emissions, etc.) and shoot for an even faster goal (low 12s) if you really wanted to. You likely will not benefit much from a ported intake, but both Advanced Induction and LE will be able to deliver what you need - just give them a call.

2.) Avoid Golen if you can. Many horror stories regarding their workmanship (PM me if you're interested). For what you're looking to do, I would do a reconditioned stock crank, forged I-beam rods (H if you ever plan on spraying - they are heavier but strong as *****), and a good forged piston. I have forged Scat I-beams and SRP forged slugs in my 383 and they're holding up quite well. I would also use a local shop, one that you can work closely with on your build, since you have a very specific goal in mind (which is a great thing). And again, avoid Golen at all costs if you can help it.

3.) A 6" rod on a stroker motor increases dwell time and decreases lateral cylinder wall loading, which is great for a N/A build. If you plan on spraying (or staying with the stock 3.48" stroke) go with the 5.7 rod.

You will need larger injectors no doubt, and a 58mm throttle body won't HURT, but it is definitely not a necessity.

LVZ2881

iTrader: (4)

Does anyobdy have anything good/bay to say about Probe/SpeedPro/ or MAhle pistons??

I found three different piston choices that look like they fit the bill, and all are comparable in top design, and Approx. COmpression Ratio.

I'm leaning towards the Mahle Power Pak as they are coated and come with the rings and wristpins, for almost the same price as buying pistons and rings seperate.

Also, what are my options for timing chain and oil pump? I know I want a standard volume, higher pressure pump..

Is the LT4 chain worth the bucks, or are there better options out there?

I've heard I may need to grind my timing cover for a DR set-up, anything else needed to run a DR chain?

And finally, will going to a 2.0/1.6 valve upgrade be worth the $$ on my set-up using an LE1 head? I realize this is something to talk to LE and AI about, but I would like some independent opinions..



I will be calling a local race engine builder tomorrow to determine If I want to go with them. I like the idea of being able to sit down locally with someone to plan this build out...

RamAir95TA

iTrader: (2)

Mahle makes a good forged piston. Stock pistons are made by Mahle also, by the way.

If you want to run a double roller, you need to delete the water pump driveshaft, and run an electric water pump. The Cloyes 3145 is most popular nowadays for double rollers. You will need to grind the cover slightly to get it to fit, but it is a worthwhile modification.

On an LE1 head I don't know if there's much benefit to running bigger valves. On the other hand, the AI 200cc heads or LE2s would likely benefit. Like you said, talk to them about it.

RamAir95TA

iTrader: (2)

By the way, the LT4 chain is a very strong piece but incredibly overpriced. For 1/3 the cost the Cloyes is just as durable if not more.

JAKEJR

In my reading, I saw that GM re-designed the LT4 timing chain set to deal with the harmonics that creeped in at the higher RPMs of the LT4. I

haven't read anything on the Cloyes chain set though, whether it was designed to deal with the harmonics.

Jake

RamAir95TA

iTrader: (2)

Wat..

fex77k

iTrader: (2)

Yea, that's why I did a Progear and a EWP.

SS RRR

iTrader: (2)

Care to offer up a source on that?

96lt1m6

iTrader: (31)

Before you state what ET is easy to hit you have to know the DA in which the car will be running in or at....... We have tricky weather to deal with out here unless you only run in March or possibly April here thats when we generally see 1500-2600 DA


In all my years i have not come across the "harmonics" card i did however hear that the Lt4 HD chain was designed to better timing accuracy and durability over the single row at higher RPM.....The only timing device i know of that will affect harmonics would be a gear drive :puke: