Billet main caps and RJC girdle?

[newtownhood]

My project from hell keeps getting worse. My factory main caps have disappeared, and I may have to buy new ones. The problem is I'm using an RJC girdle and it seems it was designed to work with flat factory main caps. Any ideas? I have another block with stock main caps that I could steal, but I still have to get it line bored at that point. I guess that would be cheapest scenario? How stout will my setup be with a girdle, billet caps, Eagle Crank and Rods?

 

[Scott Atk]

Lots of people are using billet caps with an RJC girdle. No problem.

 

[kidglok]

i think that regardless of the caps (stock/billet) they still have to be machined to fit with the girdle.

 

[NarcGN]

my motor has both an RJC girdle and billet main caps. may be overkill but it cant hurt..

 

[TurboBuRick]

Way overkill to use billet caps with a girdle.

RL

 

[jasjamz]

I have yet to see a stock main cap break on a girdled motor. The rear one is going to be expensive if you lost it too.

 

[newtownhood]

Oh, the replacements sets don't include the rear one? FAWKKKKKKK! I thought the girdle was designed to be used with flat OEM caps without necessary machining? Are there any "flat" billet cap sets? What kind of boost are you running narc?

 

[NarcGN]

Motor isn't together yet. Still waiting for the doc to install my head gaskets. I'm thinking 20 to 25 pounds boost when done nothing too crazy. Gonna be mostly a street car. I'm gonna do a E85 conversion too

 

[charlief1]

Oh, the replacements sets don't include the rear one? FAWKKKKKKK! I thought the girdle was designed to be used with flat OEM caps without necessary machining? Are there any "flat" billet cap sets? What kind of boost are you running narc?

Caps are priced individually usually. Most guys just replace the 2 center caps and go with it. To use the girdle you have to machine the caps to the block first then to the girdle. There's no way around it.

 

[pacecarta]

centers steel main (#2-#3 ) sell as a pair around 160,
front steel main (#1) is sold seperately .. around 75,
rear steel main (#4) ... cottons shows 346

all caps whether stock or billet need machining for a girdle and the rear cap needs to have spacers welded around the bolt holes
if the caps arent original to the block all caps need to be fitted to the block and need to be line bored

if the stock caps were with the block they could be machined and a line hone should be all that would be needed

the install for the caps with a girdle goes like this...
weld spacers to rear cap
machine the new caps to fit and install
cut the caps for girdle (can be done on the motor so no shims required )
install girdle and see if you need to machine the pan rail (if caps were cut in block they can check and cut rail if needed )
reinstall girdle and torque ..now do a line bore and hone
take it all apart and install the crank ,bearings and rear main seal
install the girdle

unless you are looking for 9s the the two centers are usually enough ... but needing four caps and the required machine bill to install ... unless your goals warrant four steel mains and a girdle for something like taking a run at the 8s ... id just look for another block

 

[SHADOWII]

My project from hell keeps getting worse. My factory main caps have disappeared, and I may have to buy new ones. The problem is I'm using an RJC girdle and it seems it was designed to work with flat factory main caps. Any ideas? I have another block with stock main caps that I could steal, but I still have to get it line bored at that point. I guess that would be cheapest scenario? How stout will my setup be with a girdle, billet caps, Eagle Crank and Rods?

I have a set already cut for an RJC girdle, PM if interested.

 

[WIKEDV6]

I think it’s a good idea to use Billet caps with the RJC girdle. We had a 4.1 with well over 100 passes on running anywhere form 10.80's to low 10's. The best pass being 10.009@ 132mph. Shortly after, we cracked the #2 main/thrust cap, lost the crank and so on. I did some research and talked to people here that I have great deal of respect and I was told that they do recommend billet caps with the girdle, they also had issues of stock main caps breaking as well. I experienced it first hand. So I would say at least do the middle two if you're going to push your into low 10's to high 9's.





Just my $.02
Prasad

 

[newtownhood]

PM sent shadow At worst maybe somebody can sell me a set of the 4 stocks out of a blown engine? My machinist tells me they're the same on non turbo 3.8's too. Is this correct?

 

[newtownhood]

Oh yeah... "WikedV6", I'm shooting for about 600 crank, maybe a high 10-sec driver?

 

[WIKEDV6]

Oh yeah... "WikedV6", I'm shooting for about 600 crank, maybe a high 10-sec driver?

We made 604 to the rear wheels around 30 psi with a 42/76 turbo

HTH
Prasad

 

[calais1965]

Does anyone have idea how much all four billet caps can handle?

 

[WIKEDV6]

Does anyone have idea how much all four billet caps can handle?

Well you know how it is; opinions are like A-holes, we all have one. I think if you fix the problem at the root cause then everything will stay together for a longer time. If you go to a steel crank (less flex under boost and RPM) along with two middle steel caps, that all you need unless you're trying to set some records. It should be a reliable mid 10 sec motor for a long time as long as you have a good tune. No matter how strong the bottom end is reinforcement, detonation will kill it soon or later.
HTH
Prasad

 

[calais1965]

opinions are like A-holes, we all have one.

 

[bison]

Oh yeah... "WikedV6", I'm shooting for about 600 crank, maybe a high 10-sec driver?

You dont need billet anything or a girdle for that if you are looking for high ten sec power. Just get a set of caps from a junk engine and have them cut and line bored/honed to work with your block. Spend your time and money on tuning. Fwiw machining caps to be used with a girdled block is about the easiest of all the machine work that needs to be done to run a girdle. Youre not getting out of an assembled properly machined girdled engine with cap install for under $5000 if youre using an aftermarket crank, rods, and pistons. If you want a set of caps I have a set already cut for a girdle but you will still need to line bore and shim the caps to the girdle. The center two caps are steel. PM if interested. And no i dont have any shim packs or machined spacers to go with them. You can get them from RJC or machine your own.

 

[ttaowner]

why not just use your other block with its caps? or just get another 109 with its correct caps instead on maching the caps to fit?