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Good evening, I’m looking for who makes a 5 main halo these days. I always saw j and s but he retired? I’m just looking for a little more strength for a big block I’m piecing together.Any help will be great!
Don’t bother with a 4 main halo, virtually useless unless you tie both ends together.
Depending on your timeframe I should have some 5 main halos available after the first of the year.
Don’t bother with a 4 main halo, virtually useless unless you tie both ends together.
Depending on your timeframe I should have some 5 main halos available after the first of the year.
Mark would you mind expanding on your 5 main Halo
How is it manufactured?
Metal grade ?
Thickness ?
Bolt quality?
Fit & Finish ?
Country of origin ?
General understanding is that Jim L. retired, moved to Florida and sold the girdle business to this person. Click on the link below: https://www.jsmachineolds.com/
Mark would you mind expanding on your 5 main Halo
How is it manufactured?
Metal grade ?
Thickness ?
Bolt quality?
Fit & Finish ?
Country of origin ?
It will be CNC’d. Thickness will be .500”, 5 main only.
Flatness will be guaranteed at .002 or less. Jim’s weren’t ever even close to that.
Material is yet to be determined but it will be at least as strong as Jim’s were.
It will be CNC’d. Thickness will be .500”, 5 main only.
Flatness will be guaranteed at .002 or less. Jim’s weren’t ever even close to that.
Material is yet to be determined but it will be at least as strong as Jim’s were.
Sounds like a nice piece so far.
How accurate will the hole location be as in how tight will the Halo fit around the studs?
I wasn't to fond of milling caps 1 thru 4 to meet the rear main. So I used some custom ARP studs and washers at the rear main so that I could bolt down the Halo without milling caps 1 thru 4. This also helped the Eagle stroker crank clear the Halo. Oil pump and pan fit perfectly.
Similar to pic below:
I wasn't to fond of milling caps 1 thru 4 to meet the rear main. So I used some custom ARP studs and washers at the rear main so that I could bolt down the Halo without milling caps 1 thru 4. This also helped the Eagle stroker crank clear the Halo. Oil pump and pan fit perfectly.
Similar to pic below:
That was a good job of shiming. Not sure if the bottom nut next to cap should have been threaded. I wouldn't have because it becomes a hard point. Which in turn makes the halo less effective. But I have not seen where a halo does anything to add strength to webs in a 455 block. I do think that it would help stop cap walk. Jmo
In my application I used a stud with a fixed nut above cap. The pic was not of mine. I used it for the gist of it as I did not take any pics of my actual set up.
As for whether or not it helps... well that's a little controversial. I believe it does and at least it can't hurt.
I got a question, what part number studs do you guys use for the larger 1/2" studs with a girdle? I used the 1/2" longer Ford 302 stud set with a girdle. Great for 1 through 4 on the 403. The 351W is 1/2" but ARP doesn't make a set for a girdle. If I go with a 5 main Halo, what studs work with #5? Does it have to be a ARP custom order?
Last edited by olds 307 and 403; December 4th, 2020 at 05:16 AM.
I have a Jim halo on my 468 and #4 still walked around a bit.
Is it a 5 main? I picked up a nice 1/2"+ 4 main CNC Halo for a good price. It sounds like a 5 main is worth picking up, just need to figure out what stud is used for bigger 1/2" stud rear main cap on a 403 with a 1/2" thick Halo.
Jim’s plates weren’t really indexed well. They fit better over some of the mains than others. Plus if you look closely the hole were tapered upward, not sure why he did that.
When these blocks break its normally between the caps and pan rail. So, a properly engineered 5 main halo should offer some rigidity in that area.
However I can tell you from experience that you’ll get reduced bearing wear and overall longer life if you do two things, reduce reciprocating and rotating weight, and internally balance the cranks, even small blocks.
We’re doing things with these blocks that they were never designed to do. You have to help them out wherever possible, especially as power levels increase.
Last edited by cutlassefi; December 6th, 2020 at 05:49 AM.
Jim’s plates weren’t really indexed well. They fit better over some of the mains than others. Plus if you look closely the hole were tapered upward, not sure why he did that.
When these blocks break its normally between the caps and pan rail. So, a properly engineered 5 main halo should offer some rigidity in that area.
However I can tell you from experience that you’ll get reduced bearing wear and overall longer life if you do two things, reduce reciprocating and rotating weight, and internally balance the cranks, even small blocks.
We’re doing things with these blocks that they were never designed to do. You have to help them out wherever possible, especially as power levels increase.
I am in agreement with this post. Well stated Mark.
Sorry but that’s a poor setup, NOT the correct way to install a halo.
What's wrong with shimming the oil pump main cap so that no material is not removed from 1 through 4 main caps ?
Are you concerned with the shear load on the main stud ?
Last edited by Bernhard; December 12th, 2020 at 10:00 AM.
Did not mill caps 1 thru 4.
Used ARP stud at rear main
Bernhard wrote:
Thanks for posting interesting approach.
Did you check how flat 1 to 4 main caps were and if they were even across as in level 1 through 4 ?
Had machinist check and all is dead even across 1 thru 5.
I don't understand why others think this is a poor idea !?
I've seen this in other non Olds applications.
It clears my crank, oil pump and pan is good.
I don't see why I have to mill caps 1 thru 4 for this to have the effect I'm looking for . Hmmm ..
I'm not a master engine builder or an engineer. But I'm gonna give it a try.
I have to wonder what today's engines would be if they stopped trying new things.
Had machinist check and all is dead even across 1 thru 5.
I don't understand why others think this is a poor idea !?
I've seen this in other non Olds applications.
It clears my crank, oil pump and pan is good.
I don't see why I have to mill caps 1 thru 4 for this to have the effect I'm looking for . Hmmm ..
I'm not a master engine builder or an engineer. But I'm gonna give it a try.
I have to wonder what today's engines would be if they stopped trying new things.
I agree if you are not willing to test you are not moving forward.
Thanks again for sharing your idea !
No problem !
I hope it helps.
I have changed, done and experimented lots of things when other people said it won't work. And had many great results. Maybe this is one of them !
Your studs need to come thru the nuts all the way.
But if you’re caps are even then I guess that’ll work. However I’d still be a little concerned about the alignment with the rear cap.
Nothing is torqued down. Nuts are on loosely.
if when I torque down mock up and I feel I do not have enough thread I will change them out for longer ones.
Thanks for heads up !
Remember... Some of Mankind's greatest discoveries were made by thinking out side the box.
Nothing is torqued down. Nuts are on loosely.
if when I torque down mock up and I feel I do not have enough thread I will change them out for longer ones.
Thanks for heads up !
Remember... Some of Mankind's greatest discoveries were made by thinking out side the box.
Rule of thumb three to four threads above nut when torqued. Anything less than two is to short. Other than that looks good to me.Jmo
VORTECPRO what are your thoughts on the Halo for mild HP builds? Also on installing the Halo without cap milling 1 to 4 and shiming the number 5 main using the nut and shims if necessary?
Thanks
Bernhard
Location: Colorado Springs Colorado/Thousand Oaks Ca
Posts: 1,719
Originally Posted by Bernhard
VORTECPRO what are your thoughts on the Halo for mild HP builds? Also on installing the Halo without cap milling 1 to 4 and shiming the number 5 main using the nut and shims if necessary?
Thanks
Bernhard
Hmmm, we don't run them in NHRA stock. I guess if I was to run this setup I would: Cut all the caps very carefully for the line hone, I'd bring the housing bore down to .0015 from final size (line hone), I then would clean the hone oil off the block and put it in my mill and un TQ one side of the main studs and fly cut the tops of the main caps 1-4 to even the heights, then spot face the #5. I then would re TQ the studs I took out, then remove the studs from the other side and fly cut until even. I would then shim the number 5 cap even with the 1-4 caps. Then I would loosen all the caps and re TQ with the halo in place and TQ up the oil pump, then bring the line hone into spec. And this would be expensive.
The last 455s I've built I took so much weight out of the bottom ends it probably is a lot easier on the block. When you take a crazy about of weight out of the balancer and flex plate its not far from internal balance.
I'm no Olds expert and don't claim to be but, I've seen several 10 sec full weight Olds without girdles never hurt a block or a bearing, but maybe when you start making real power it can become a problem. I know the Buick @ 600 HP and 7000 RPM is a problem. If I had to run a girdle on a Olds the block would be filled.
Last edited by VORTECPRO; December 13th, 2020 at 07:42 PM.
Location: Colorado Springs Colorado/Thousand Oaks Ca
Posts: 1,719
Really we should be looking at how Chads block is done I assume its a production Olds block, for a car to run the MPH it does you have to turn over 7300-7500 RPM in the lights, which he's done consistently.
November 30th, 2020, 04:10 PM
