We luv ya Bob!
Just a note, Faron (
FordSedan Delivery)didn't go this route on his 220 hp 250 12:1 engine, he used an old cam grind with not much lift, not much duration, he didn't need 1.73 or 1.76:1 rockers to get his 12 :1 compression, 14 second 66 Mustang to do high 95 mph passes.
He just followed the 1971 Ak Miller based articles and built the engine they way he saw fit. Gene I think has that engine now. Faron mearly said to us all that he liked to use lash caps to fix up any clearnace issues on his race and road FE engines, and that he was quite happy having a solid lifter rocker gear. Faron says quite a lot of very revolutionary things about everything, we just didn't get it the first time around.
I'm breaking my comttment responding to this post, but it it helps, then its all good.
Why would I go buy an Aussie twin roller chain and broach it for a US US 250, when there is so little market for it?.
Mike1157 found the A series Mini 1275 double roller chain and similar 18r Toyota and 308/304 Holden twin roller chain was able to be matched with a 5.0 aftermarket sprocket on a US 250. So if you want one, get your enginer dude to have a go, and set up your own service.
Its basically just a machining operation that will cost you the time to rework the existing parts. JP make it from common white box supplies, but even Diecrest don't have any customers for a 250 gear drive, and there were about 4 million 250 engines made between 1971 and 1992. Al using US technolgy. And we make 350 to 400 hp naturally aspirated 4.1's down here from taxi cap engines, with blister pack rings and bearings and often locally made knock offs of US pistons.
IMHO, its not engineers. Engineers do for 10 dollars what costs you 100. They are like lawyers at the bottom of a lift shaft, a good start culling off the bad ones, but a nessesary evil. I think back in the day, Mao Tse-tung asked his subjects to eliminate all the sparrows out of Shaghai back in the 70's, but it created an insect problem....
There is no way to collapse the quality price trade off in your favour excpet by informing you.
You just have to bite the bullet, and do it. If you've gotten a good price on the rockers, then props to you brother...its becasue an Engineer has gotten off his butt and done the work for you.
I've done the rocker swap here using borrowed FE rockers myself, cost an armload for stuff s relative to a Chevy 350, cheaper here in New Zealand than it is in the USA. Its all supply and demand. The Aussies down here, form import and locally made sources, sold only about 2500 new Small block Chevy 350 engined cars a year from 1971 to 2016, but over 60000 per year in line sixes per year between that time. So its 24 times more expensive to do a Small Block Chevy than it is to do a any in line six down here. That's why the solutions are now Australian and why your getting tcked off. The cost of doing a 5.0 SBF or SBChevy of any kind will keep dropping, and its unlikley anyone here will help collpase the service price equation.
Back in the day, we made for 700 milion dollars a 240 plus hp 15 second streat pounding Ford in line six sedan that would whip the hiney of any Ford car made anywhere, but no one wanted it. They buy Camry's instead. So its just the way things is heading. LOL!
I do my information for free, but not my product. I'm broke as any New Testment apposle except Judas Isacariot on a Thirty pieces of silver performance bonus, spending a percentage of my time helping you guys. Becasue you'll have saved me thousands over the 15 years I've been here. Thanks everyone, and a large amount of info is from engineers here.
Its a take it of leave it deal. If it don't help you none, just don't read my posts. It's nothin I take personally. Some people just like milk, others want to meat.
You've gotten what you need on the rockers, job done for me.
You've now gotten a free rundown of what you need to do to do a SBF 5.0 timing gear conversion with a cheap Indian twin roller chain that British Motor Coprporation designed to win the Montecarlo in 1963, then Toyota used a similar version as did General Motors Australia as they copied it on the updated 1969 Holden 253/308 HQ Monaro engines chain. That chain won the Australian Touring car championhip's 163, 621 mile race in
1966 Morris Cooper S 1275 (130 lap, 500 mile race)
1975 Holden LH Torana L34 308 (163 lap 621 mile race here on)
1976 Holden LH Torana L34 308
1978 Holden LX Torana A9X SS 308
1979 Holden LX Torana A9X SS 308
1980 Holden VC Commodore 308
1982 Holden VH Commodore SS 308
1983 Holden VH Commodore SS 308
1984 Holden VK Commodore SS 308
When the timing chain was down graded to single roller, it still won, but failed at Monza.
1986 Holden VK Commodore SS Group A 304
They then homologated the 1971 HQ Holden 308 timing chain again, and kept winning.
1987 Holden VL Commodore SS Group A 304
1990 Holden VL Commodore SS Group A SV 304
1993 Holden VP Commodore 304
Then the 5.0 Ford twin roller timing chain set, won Bathurst seven (7) times, but the 1967 win in a 289 hp 225 HP V8 also used a similar chain on the 1967 Ford XR Falcon GT 289, so it could be 8 wins
1994 Ford EB Falcon Boss 302
1998 Ford EL Falcon Boss 302
2006 Ford BA Falcon Boss 302
2007 Ford BF Falcon Boss 302
2008 Ford BF Falcon Boss 302
2013 Ford FG Falcon Boss 302
2014 Ford FG Falcon Boss 302
So if you use a timing gear like
Mike1157's and an Indian made twin roller timing chain, then you have 7331 miles of race proven reliablity in the chain, and about, oh, 4347 wins on the timing gear set.
Thus end the words of
xctasy...
