So guys tell me what you think of my mild and "budget" 383 build.
This was my first build so I didn't want to go too crazy ($-wise) and end up with a trash heap on something I messed up and I learned a lot (especially about buying motors with bogus parts.... ...on the forum )


But anyway...

-1970's 4 bolt main 350 bored 30 over
-Scat 400 crank
-GM Pink Rods
-Speed Pro Hyperuetectic Pistons (12cc dish)
-LPE 213 cam: 224/234 .496/.520 w/1.6 112cl
-Ported Dart Pro1's 200cc
......flowing:
lift int exh
.0200 138 101
.0300 197 152
.0400 240 183
.0450 256 194
.0500 268 200
.0550 280 206
.0600 283 210
.0650 285 210
-Mildly ported LPE Superram with all pieces portmatched and matched to a 1205
-LPE longtubes
-7 qt track pan


I think/hope this should make a fairly strong yet very streetable combo, I also think with those heads and intake I left a lot on the table with a mere camswap. Ohh yeah, I have been coming up with CRs of around 10.0.

So guys, what do you think?
Am I going to have a beast or a sick dog? (Predictions?)

If there is just a glaring mistake please point it out, as like I said, this is my first time.


A pic of the mock-up I took last summer (though I have swapped heads and intake from this picture)


The engine build/swap will resume hopefully in about a month.

 

It looks and sounds like a runner. Let us know how it works out.

RACE ON!!!

 

I think it will be a very strong runner, I went ahead and put that combo in Desktop Dyno, here it is. Also, who ported your Dart's? It looks like they got some good numbers out of them.

 

500 lb of torque at 2000 rpm? Arn't those big block numbers?

If correct, those numbers are sweet!

 

Those are great numbers eh?
Only one problem, I forgot to mention...the camshaft is flat tappet not roller.
That should bring it down a little.

Travis, Thanks A TON for running that DD. I was curious what I should expect, would it be too much to ask to get you to run it one more time with a flat tappet instead of the roller cam?

Thanks guys!

 

USAsOnlyWay: I think it will be a really strong runner, what is it going in?

Also, I'll ask again, who did the port work on your heads, and are the intake valves 2.05"?

No problem on the DD, Here are two more with the hydraulic cam setting and the solid flat tappet cam setting. I think the hydraulic is a little on the low side of what you'll actually see.

Hydraulic


Solid

 

Dah sorry I didn't answer before, I thought I did.

More performance in Charlotte did the work on the heads.

I believe the valves are 2.06 & 1.65.

Also, it will be going in an 86 Corvette!

Thanks again, I sure wish the numbers were more reflective of the roller...man that makes a big difference!

 

I think DD is a little optimistic with rollers and pessimistic with hydraulic flat tappets. It sounds like it will pull hard, I think you'll be pleasantly surprised when you take it out and hammer the loud pedal.

 

sounds like it's going to be fun

 

Excellent, I will keep you guys posted when I get back home and resume....look for it in about a month or so!

And THANKS!

 

What brand headers are those? Are those merge collectors?

 

LPE headers.
Made by Lingenfelter for C4s, they stopped producing them a few years ago. These were recoated recently by HPC. (In utah I believe)

Merge collectors, as in they all come into one 3" pipe? Yes they are, there is also a hole for an 02 sensor.

 

A merge collector necks down into a smaller diameter before the collector's end. Man that is bad description.

 

I get it though. Thanks!

Zix, no I believe it is 3" straight.

 

-GM Pink Rods
-Speed Pro Hyperuetectic Pistons (12cc dish)

With so many choices of modern forgings I would skip these two items. You can buy rotating kits in all price ranges. I've bought some kits from www.flatlanderracing.com

You want to keep your compression up with that much cam. Mid 10's are not a problem.

 

Just reading this thread and wanted to ask a few questions. I'm intrigued by the 383 and have seen a couple pull on the chassis dyno at Carlisle. I love the broad torque band of this motor and they also seem to sound different to me.

Besides a rotating assembly, what additional requirements are necessary to stroke a 350? Assuming $450-500 for a cast rotating assembly, what additional machining costs are involved and or, other work and parts to complete a good 383 short block?

If all other things were the same on a 350 vs a 383, what would the gain in TQ and HP look like on the 383? What does the strock have to do with HP and TQ, aside from a longer stroke increasing cubes?

Does anyone know why GM never offered a 383 in a truck or a car? I love the TQ band of the motor. What's the downside?

 

Gkull, thanks for the input, let me explain a bit better about the choice of Hypers and GM pink rods.

I bought the shortblock on the forum, it was advertised as having forged TRW pistons, when I recieved the shortblock I noticed the pistons did not look like they were forged. I pulled one of them and found it was a Hyper.

There was no effort on the seller's end to try to reimburse me at all for the crock-of-S#$# he sold me. Also besides being misleading about parts, the guy also shipped it to Seattle, WA. We agree to my house as the shipping destination, ~300 miles away. So I borrowed a friends truck and drove over to pick up the motor. He never reimbursed me for the HALF of the Gas that we agreed to.... ~35$, (I thought that was very fair the amount of trouble it took me to borrow a truck, drive over on a weekday, load up the engine, and drive back). The engine was also supposed to be shipped in a crate...it was shipped ON a crate. As in, it was in a black garbage bag on top of a wood palette also when the engine arrived it was missing two lifters. He told me to go buy them myself... I pulled apart the motor, upon inspection I found that the crank bearings were pretty badly scored. The seller insured me that the motor was under 5k and in perfect condition... I had the rods and pistons checked, they were OK. So since the Hyper pistons had pressed in rings, my mechanic said chances are, we would break them trying to take them off...so I decided to just reassemble with a turned crank and new bearings as I wanted to build this on budget and I couldn't afford to do anything else at the time ... (Read: Trying to do this while going to college) So anyway, that is why there are the GM pink rods and Hyper pistons.


I know that forged pistons would be safer, stronger, and so forth and I will definitly use them next time. For now though, this will have to work. Hopefully it does...

 

"Pink" rods are forged.

RACE ON!!!

 

Dah! I meant to say pistons...
However, I didn't think that they were forged anyway?
Hmm, thanks CFI!

(note: the crank is just a scat 400 cast crank)

 

USAsOnlyWay: I wouldn't get too worked up over the rotating assembly, it sounds like it will be just fine. And that Scat Crank can take a lot of abuse.