4 bolt or 2 bolt? Ken what do you think?

I am sad to tell you that I have seen while installing a bigger oilpan, that I have a 2 bolt block.

I know a 4 bolt block is better than a 2 bolt block, but the most 4 bolt blocks are damaged, and I can have a used one.....instead of using my own engine.

The tuner says that, using my engine, made it new inside, JE pistons, balance and bore the thing, compression ratio 1:8, I can put a Whipple charger on top of it and boost 500 hp.

he says: the 2 bolt can do fine, don't go futher than 6000 rmp.


Please comment.

[-=Jeff=-]

Originally posted by johnny
I am sad to tell you that I have seen while installing a bigger oilpan, that I have a 2 bolt block.

I know a 4 bolt block is better than a 2 bolt block, but the most 4 bolt blocks are damaged, and I can have a used one.....instead of using my own engine.

The tuner says that, using my engine, made it new inside, JE pistons, balance and bore the thing, compression ratio 1:8, I can put a Whipple charger on top of it and boost 500 hp.

he says: the 2 bolt can do fine, don't go futher than 6000 rmp.


Please comment.

Johnny, are you changing the fuel in jedction for the whipple charger?

As for the Block, you could use your blocka nd have it drilled for Splayed Main caps.. this will be stronger then OEM 4 bolt blacks as the outer bolts are canted into the block.

Another thing you should do is use ARP Main studs instead of bolts.. again for strength.

What is the complete combo that you have planned?

[Ken]

If you're going to use a two-bolt block and modify it to fit four-bolt mains, use a truck block; it's got more meat. Two-bolt main blocks though, are good for up to around five-hundred horsepower if you don't spin it outrageously fast (kept around 6500 rpm).

_ken

[hotrodd]

Just my opinion but 2 bolt does'nt crack out like I have seen on 4 bolt. I turn 5800 on 2 bolt and about 375 horse with no problem's.I know this can be a heated subject, but is what I see. Right now I would much rather have a way to put that clip on the clevis pin that connect's the brake pedal to the master cylinder! Man that can be testy,also I found a nut behind another that held the booster and a nut that held the wiring harness in place. double nutted,couldn't see good enough that it was that way and the fight was on and I finally walked off and came back and found it and got everything under control.Thought I was going to have to say heck with brake's and drag my feet like Fred Flinstone

[Ken]

I may look for it later, but I posted a few comments from Chevy High Performance magazine here several months ago. Basically, it stated the same things we're telling you Johnny. Run a search for it (two-bolt vs. four-bolt or something like that.)

_ken

So, it is true, 2bolt could be better than the 4 bolts. And modifed it to the 4 bolt is better than the original 4 bolt.....mmmmmmmmm.........I ask around.


Jeff,

The setup I have in mind is a compromise between hp and money. I wanted the 427 small block from Bill Michell, but a don't have the money for it. At the other hand, I aready run 172 mph with the vette...awsome fast!

So my compleate setup will be:

355 cid low compression 1:8 use JE pistons, also better rods, lifters, balance and blue print the thing......other cam....

remove the LPE SuperRam and build a whipple charger on top, modified the manifold for injection....I have already a sequential injection :t

I use my Edelbrock performer heads and crane roller rockers goldseries, tpis headers 1 3/4 ", B&B triflow 2,5" exhaust, no cats, no airco, no egr.......electrical waterpump and electrical steeringpump.....58mm TB holly

Boost at 0,5 bar = 6 or 7 psi (than I do not need a intercooler or a aftercooler)


I hope for 100 ph more at the rearwheels.....is about 465 hp under the hood......I think the vette will pull as fast in 5th as it does now in 4th!!

But don't forget...there are also other mods you have to do at your vette besides enginepower....like brakes, shocks, etc.....

[Ken]

Hey Johnny, I like your new signature, but I'm beginning to wonder if you can "pump up the volume" anymore in a street-based Corvette. Awesome man!

_ken

I was at the factory of the Whipple chargers...hehehhehehe....and I can buy there the biggest single charger compleet with pully and pressure vale for less then 1200 us$, hehehehe....this baby boost max 1,2 bar on a 350 cid....and 0,5 bar on a 427 cid......and from about 1500 rmp...all the way up!

When it is installed.......takes a while.....I inform you.

[Twin_Turbo]

The later 2 bolt blocks are better castings than the 4 bolts (except for 010 020), they have a hicker nickel & tin content for better pouring during casting. If you convert your 2 bolt to a splayed 4 and fill 2/3rd of the waterjacket with some block rock you will have yourself a motor that will be very sturdy, very near to a bowite block (not counting advantages on the bowtie like priority main oiling and enlarged oil galleries)

Do have the block bored and honed after filling, the curing will warp the cylinder bores.

A STUDDED! 2 bolt will hold up to around 500Hp, it's revs that kills bottom ends, this is especially true for stock rods. Bearing clearances are critical.

If I were you I'd have my block prepped w/ the correct deck height so you can set quench height w/ the head hasket, this will severely minimize the tendency to detonate.

The critical part is keeping the cap on the block, studs do a better job at this. If the cap comes off a tad the crank will break, especially forged cranks. Cast oens can handle less load but they flex a little. Not saying cast is better here but cap retention is more critical in a block /w forged crank.

Think bearing clearances, don't cut corners.

On the honing part, either step hone the block to the smoothest finish possible so you can run moly rings and stainless steel top ring. If you want any significant amount of boost think about having the block O-ringed and 400 gaskets.

Marck