main cap ?

93ty475

Donating Member
Re: main cap ?

scotts4 said:
my splayed bolt for my 4 bolt do not go into my water jackets .

Whether they went through or not, I guarantee you they got close....One of my four leaked, but I sealed all four anyway....
 

scotts4

ADDICTED
Re: main cap ?

i did not test it but i checked and there where no sines of it when i had the motor in it before i never got any coolent in the oil and i never lost any pressure with a pressure test of the cooling system all i used on the bolts was molly lube .
 

scotts4

ADDICTED
Re: main cap ?

yes he did it he has done tones of them . are you going to use him for your work ? give me a call
 
Re: main cap ?

This to me makes no sense. If this were all true I cant imagine why anyone would be doing it. I can maybe see the splayed caps drilling into the water jacket; but making the block weaker? Most engine failure is from moving parts. I know RPM and Capbell do 4 bolt main conversions. They know the 4.3L just as good as anyone and they have a record to proove it. I dont think they would waste their time with something that weakens a build. Yeah, the extra bolts might weaken the block in a scientific world but that does not out-weigh the gains of keeping the crank down.
 

bezerk

New member
Re: main cap ?

as i believe it makes the crank last longer, instead of weakening or strengthen the block itselve.
Also i had a misfortune with spun bearing with a leaking 4 bolt conversion.
not going to let out some names again, anyway, he kinda blamed me, and since than he uses RTV on the bolts. :dunno:
 
Re: main cap ?

Wouldn't a good shop know if they drilled into a water jacket? If you dont have splayed caps then problem solved. There are no jackets strait down.
 

bezerk

New member
Re: main cap ?

Wouldn't a good shop know if they drilled into a water jacket? If you dont have splayed caps then problem solved. There are no jackets strait down.

as some people say 4 bolt mains make a swiss cheese out of the blok doing it., i agree that non splayed caps are a waste of money, because you are going to put the tention on it 1 on direction verry close to eachother, as in splayed make the stretch go into an whole other direction and guide it away from the stock 2 bolts. than again, drilling into the waterjacket ain't no big of a deal if sealed.
 
Re: main cap ?

How is it a waste with regular 4 bolt mains? You still have more surface area holding the main cap down. not as easily twisted because the cap seating is wider. I agree splayed will be stronger. But I dont think un-splayed is a waste.
 

Synister

New member
Re: main cap ?

So whats the verdict on this? I'm about to get it done.. Are splayed 4 bolts caps getting into water jackets or should i just run the standard 4 bolt with main studs?
 

autoaddictions

Active member
Re: main cap ?

Ask yourself this. How much power am i going to make . If its less than 400 you wasting your money and there for HGAS. leave it 2 bolt. You will need to line bore the block for the 4 bolt mains.That adds alot of cost to the machine work as well.

My block Has splayed 4 bolt mains. I make at least 600hp I have no water in my oil!!!

Now the questions do you nitrate the crank or not?? does freezing it really make it stronger.
 

Synister

New member
Re: main cap ?

Ask yourself this. How much power am i going to make . If its less than 400 you wasting your money and there for HGAS. leave it 2 bolt. You will need to line bore the block for the 4 bolt mains.That adds alot of cost to the machine work as well.

My block Has splayed 4 bolt mains. I make at least 600hp I have no water in my oil!!!

Now the questions do you nitrate the crank or not?? does freezing it really make it stronger.

Good info thanks!
 
Re: main cap ?

Ask yourself this. How much power am i going to make . If its less than 400 you wasting your money and there for HGAS. leave it 2 bolt. You will need to line bore the block for the 4 bolt mains.That adds alot of cost to the machine work as well.

My block Has splayed 4 bolt mains. I make at least 600hp I have no water in my oil!!!

Now the questions do you nitrate the crank or not?? does freezing it really make it stronger.

I hear cryo treating is a gimmick. That's just what I found when I did the research on it. It might not be but there is a lot of contradicting info on this. Ask any cryo company for data on the before and after strength and they typically do not have any.
 

jharrison

New member
Re: main cap ?

I don't know about cryo-treating, but heat treating via nitriding does harden the metal and gives it more fatigue strength. Addmittedly I am no engine builder, but I do trust certain companies, RPM is one of them. If they do it on their high HP builds, there must be some advantage. I tend to use RPM's website as sort of a guide. Looking at their motors a nitrided crank will hold 600HP with 2 bolt mains. Adding splayed 4 bolt mains and block filler to the lower half will hold up to 750HP.

http://www.sytyperformance.com/inde...facturer_id=0&option=com_virtuemart&Itemid=26

"Nitriding steels offer many advantages: a much higher surface hardness is obtainable when compared with case-hardening steels; they are extremely resistant to abrasion and have a high fatigue strength." -about.com

My philosophy has always been "it's better to have it and not need it, than to need it and not have it". I would rather add the 4 bolt mains and nitrided crank even to a mild build just for that extra strength that may come in handy when pushing the truck later. Just my :2cents:
 
Re: main cap ?

How is it a waste with regular 4 bolt mains? You still have more surface area holding the main cap down. not as easily twisted because the cap seating is wider. I agree splayed will be stronger. But I dont think un-splayed is a waste.

The THEORY behind straight 4 bolt mains being a waste is that the main webbing is only so strong. Its THIN if you;ve noticed. If you machine it for a straight 4 bolt there is more clamping force but the main web can still move around and or get ripped out at higher power levels.

With a splayed cap you are fastening to the material near the pan rail and not the main webbing.
 

92 Ty 1173

Active member
Re: main cap ?

My machine shop does alot of dirt track engines and other race engines and insisted that a four bolt conversion was not necesary for me cause my expected hp levels were not real high and it would be a weekend warrior at the most. A good balance job and a good stud kit is all he reccomended. He's been in the business for about 30 years so I took his advice. And like auto addictions said it was quite a cost for the conversion, not only the parts but all the machine work. Just my .02.
 

Don W.

Stab it and steer it
Re: main cap ?

Splayed caps with bolts into the jackets here with no problems at all. At least not main cap problems... :)
 

turboj91

New member
Re: main cap ?

To back up Dave's theory with detonation, a great majority of the SBC "010" blocks (casting # above the oil filter on trans mount area) were installed in truck applications where severe duty was expected. Hauling a heavy load (or pushing if using a snow plow) would have more tendancy to detonate than a light load passenger car application.
 
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