Chevy 2 bolts VS 4 bolts

[Jesus]

Hello all,

I have a doubt about the chevy 2 bolts engines and 4 bolts engines.
I know that 4 bolts are stronger, but how much?, wich is the limit in power and torque for a 2 bolts?,

As far as I know many 350 and 400 sb have two bolts and works fine as well as all the LT1 and LT4 engines that are very powerfull.

Jesus
GD, next summer will be finished, I hope.
Granada, Spain

[robert]

It isn't a case of how much power, it is a case of how long will a tuned 2 bolt last for. My advice is to go for a 4 bolt, that was there are no dramas when you decide you want more HP, and that will happen.

The next question is splayed caps or not. Personal preference is for splayed caps as they spread the load a bit better.

2p as usual.

Robert
Forum Admin

http://www.cobraclub.com/flags/UK.gif

[kdavies3]

Hi Gang!
I have to agree with Robert on this one. I'm sure you can find lots of reading matter that will say a two bolt is fine.
As the man said for how long? maybe for it's life in a low tune engine, let's face it there's a reason why those chaps at GM went to four bolts.
As did those very nice chaps at Rover go to cross bolts (I was one of them).

Bottom line if are producing a lot of BHP and Torque and more importantly using it regularly, I think you have to go four bolt.

JMHO. :7

cheers

Kev Davies

[daxv8man]

Whilst we are on the subject of Chevy engines, all of you that have bought
350 Chevys. Can you give me the price you paid for it, and was it a turnkey
engine , who from? and have any of you imported from the States ? and again
who from. this is for some research I'm doing. I know there are various options
on the 350 but i will compile a list of details as i recieve them, this will
hopefully give me an engine that is the most popular to use in a Cobra.
thanx for your help.

Graham

HAPPY BLASTING

[chris m]

Graham,

This would be useful information for me too, would you produce a summary of the options/costs(ish) so we can all take a look?

Chris

[JimT]

The more important issue is the quality of machining performed on the block, a well checked/machined 2-bolt block is good for over 550bhp when good quality studs are used and torqued up correctly.

I concede that 4-bolts ultimately are stronger but I don't think its worth worrying about unless your constantly revving over 7000rpm with nitrous or a blower (ie. racing), under such conditions I'd be more concerned about the quality of my con rods and big end cap studs.

Jim.

(with a 2-bolt block :P )

[daxv8man]

The reason i ask is that it's still cheaper to import than to buy here,
if there was a demand for it i can import engines from the engine factory.

So i would want to know what spec and what engine was wanted, i could do this
every three months ,if any one was interested.

Graham

[mikey]

If you have a two bolt mains, it is a relatively simple task to change it to 4 bolt at a later stage. You need to buy the caps and have the block machined and tapped to take the longer caps and bolts. Preference is for studs if you are going for power. Its not about strength it is to do with the stress distibution characteristics of a stud and nut as opposed to a bolt.
Mike.

[kdavies3]

Hi Graham,

I shipped my 383 ci stroker in from Florida "theenginefactory.com".
Supposedly 450 HP and lbs/ft of torque. Matt Walsh there was very helpful throughout and arranged shipping etc.

Total cost £6100 including all taxes, duties and shipping costs.

Price includes air cleaner, chromed alternator, pullies etc.

Hope to fire it up this coming week.


There are people a lot closer to home who can supply engines, EDA, Real Steel, Repower etc.

There have been a number of posts on the subject recently.