Guys,
I'm going with a forged 383, LE2 heads, and a D1 with the SDCE tensioner. Since the motor is apart I'm contemplating whetheror not to spend the extra $500 on a 4 bolt splayed main cap conversion. I talked to the engine builder and he said if it was his car that he would just go with ARP main studs and that the caps were overkill unless I was planning on making more than 650 rwhp.

What do you guys think? I don't know if I plan on going with n20 or maybe upgrade to a F1 blower in the future.

-B

 

There is only good in doing the coversion. I have a 400 small block and an LT1 that I am converting to splayed 4 bolt with arp Studs. It may be overkill but in the end I feel its worth it!

 

he has a valid point,it is similar to putting a 9" in your car instead of a 12 bolt,its a matter of personal preference along with possible upgrades.
another way to look at it is,if you are building an engine to beat on it,it should be able to withstand the abuse.you will be using a steel crank its heavier than a cast steel crank and yes a studded 2 bolt will handle the added power and stress however,using a 4-bolt or splayed conversion will provide the strongest hold you can provide especially with an EVERYDAY block casting..
drag racing:normally aspirated
2-4 bolt block good idea(properly machined)
eagle ESP rods
JE/SRP forged pistons
machine shop that builds race engines
eagle steel crank or lunati dragon slayer
BOOSTED APPL.
no doubt a 4-bolt or splayed
when boost comes on,nitrous is activated the stress your engine goes through would really freak you out!its gotta be in place...

 

From the specs I got on your motor from Lloyd you pretty much HAVE TO do a 4 bolt cap conversion.

A D1SC @ 15psi with ported AFR heads can get you into 650rwhp range....

If it was me I don't know if I would keep speaking to that engine builder, that's just scary that he would build a blown 383 that's 500hp+ easy and not do that.

Bret

 

Nice to find that my cam grinder speaks! If thats the case I'll go ahead and tell the guy to do the 4 bolt splayed conversion. I am assuming most people are going with the Pro-gram caps on number 2,3, 4, and going with ARP main studs on # 1 & 5?


-B

P.S. The heads I have are LE2 ported stock castings. If its not too much trouble can I touch base with you in regards to the specs on the motor?

 

He was asking about a 4-bolt SPLAYED cap, not a 4-bolt cap.

Either way, You don't really need splayed caps unless you're running well over 1000 horsepower or something absurd like 7500+ rpm.

You could just get an LT1 Vette or LT4 block and simply upgrade the caps and bolts.

 

Okay now i'm confused....

-B

 

I would spend the extra 500 and not have to worry about it.I am getting it done and I likely will never see over 650 rwhp(with N2O) on my car but it is solidroller and will be spinning it kinda high(7000-7500 or so)

 

Don't be confused.... just go ahead and do the 4 bolt conversion.

Use ARP studs on all the mains.

This is a a straight 4 bolt cap



This is a splayed 4 bolt cap



If ya got some questions, e-mail me.

Bret

 

blown383 just go with the 4 bolt main setup, (comes standard on the LT1 vette's) 4 bolt splayed is suppose to be stronger and like Kraest said its really only needed with a 7500+RPM motor with around 1000 HP.
4 bolt splayed is nice but not needed 90% of the time IMO. Just be sure to use ARP Hardware in the motor .

I have a similiar setup, LE ported AFR LT4 heads, Ported LT4 intake, Monoblade, Victory racing 9:1 Forged 383 and we are just going to use a 4 bolt main setup (NOT splayed) and I have a D1 kit coming in the mail with a FMIC setup. Should make around 650-700RWHP in the 12-15lb range.

Not to confuse you but, what if I said 2 bolt mains was stonger than 4 bolt mains SOMETIMES, but that is a little more advanced I suppose

 

I bought a 96 Vette block that came with Oliver Billet 4 bolt Mains with ARP studs and bolts. I got lucky my block was already machined for a 396.

 

I'm calling BS on the 4 bolt is not needed 90% of the time Ben.

If you have 500hp or more in any form you can easily hurt the motor, especially on something like a stroker with heavy parts or a strong NA setup with a 150 or more shot.

I've seen way to many guys do it.... just because there are a lucky few, doesn't mean it's a good idea.

Bret

 

I just put the order in and the engine builder quoted me $625 on top of the other machine work.

$120 for the ARP main cap stud kit which includes the bolts for the outter splayed holes.

$350 for the machine work

$155 for a set of Pioneer billet splayed main caps. Anyone ever use the pioneer billet caps?

-B

 

Once again, you're misreading. He said 4-bolt SPLAYED isn't needed 90% of the time.

Mike

 

Sounds about right. I paid around $600 to have my 2-bolt block converted to a 4-bolt splayed.


I've only heard of Pioneer audio equipment

I used Callies crank, rods, and caps on my 396.

Mike