That shouldnt be long. I destroyed my 2.76 7 1/4 pegleg in just one year behind my 318 with just the following;
Lunati 10200701 cam
Performer intake and 600 cfm summit carb
And only stomping on the gas at every second stop sign.
Finally the decision has been made.
- Thread starter dartfreak75
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That shouldnt be long. I destroyed my 2.76 7 1/4 pegleg in just one year behind my 318 with just the following;
Lunati 10200701 cam
Performer intake and 600 cfm summit carb
And only stomping on the gas at every second stop sign.
doogievlg
Well-Known Member
Don’t want to turn this into a rear end thread but you might be surprised. Mine last years behind my 360 including trips to the drag strip.
MopaR&D
Nerd Member
As long as you have skinny/slippery rear tires that 7 1/4" will be fine, also don't go around doing massive peg-leg burnouts (wrecks the diff spider gears). Mine held up fine behind a built 360 Mag because I had 225/70-14 BFG Radial T/As on the back, then when I swapped in the B-body 8 3/4" I upgraded to 275/60-15 Firestone Indy 500s (discontinued now).
It may be a tad soggy off the line with the stock gearing and TC but it won't be terrible, it's not like you NEED to upgrade those before the car is driven or it'll blow up lol. Just be smart and take it easy.
Same with the carb, it might not be "ideal" but the only thing you'll notice is a bit less power on the top end compared to a 750 cfm or so. That can be upgraded later. I would definitely recommend a Performer RPM intake or similar though, factory iron 4-bbl intake is good but not great especially on something with a decent cam and compression.
It may be a tad soggy off the line with the stock gearing and TC but it won't be terrible, it's not like you NEED to upgrade those before the car is driven or it'll blow up lol. Just be smart and take it easy.
Same with the carb, it might not be "ideal" but the only thing you'll notice is a bit less power on the top end compared to a 750 cfm or so. That can be upgraded later. I would definitely recommend a Performer RPM intake or similar though, factory iron 4-bbl intake is good but not great especially on something with a decent cam and compression.
AJ/FormS
68 Formua-S fastback clone 367/A833/GVod/3.55s
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9.1 is low for that cam,IMO
At your stated ~7.5 Dcr the cranking pressure is likely to be about 145psi,but it's a slow-ramp comp, so who knows what the pressure will truly be.
The A999 will be a welcome relief, as the starter TM climbs to 7.56. That's gonna be a big help.
EDIT, sorry I got my cams mixed up, disregard the slow-ramp statement. Thanks be to nm9 who caught this
I ran mine at 10.9Scr @185psi. (aluminum heads). That made it a dump-the-clutch deal with a starter gear of 9.44;my favorite iteration. I loved that cam. I was very sad when the lobes starting falling off it.
At your stated ~7.5 Dcr the cranking pressure is likely to be about 145psi,but it's a slow-ramp comp, so who knows what the pressure will truly be.
The A999 will be a welcome relief, as the starter TM climbs to 7.56. That's gonna be a big help.
EDIT, sorry I got my cams mixed up, disregard the slow-ramp statement. Thanks be to nm9 who caught this
I ran mine at 10.9Scr @185psi. (aluminum heads). That made it a dump-the-clutch deal with a starter gear of 9.44;my favorite iteration. I loved that cam. I was very sad when the lobes starting falling off it.
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Jax340Dart
Well-Known Member
DF 75, Sorry it took so long to get back to you, I had to get up at 5:00am work all day and now fight a blizzard comming in till Thursday night. Anyway the springs came with the kit 73195k1. The installed height is 1.700. I think the spring number is 73195-16. They are dual springs 1.437 OD. Oh by the way, I have the 273 adjustable rockers
nm9stheham
Well-Known Member
Uuuuhhh.... I never knew a Voodoo HFT grind was considered a slow ramp cam....????
dartfreak75
Restore it, Dont part it!
Thanks buddy I gotta do some measuring on my heads. When I do I will follow up. I will look you those springs the spring lunati recommends is a different part number. I have a box of brand new comp 901-16 I bought for the 318 i dont think they are going to work now. Lol oh well i will keep them just in case I ever do need them.
dartfreak75
Restore it, Dont part it!
The tires I have are 235 75 15 they are Walmart radial tires (Douglas brand) so I don't expect them to grip too good. I'm not to worried about the rear end I dont plan on racing or anything probably wont even do any major burnouts. I have a 8.8 I pulled out of an explorer waiting. I dont have the money to put into it yet. I need a short side axle new brakes new pinoin yolk shock plates axle arches I have read I'm gonna have to shorten the driveshaft. So I'm figuring 500 to 600 bucks there. So I'm just gonna stick with the 71/4 and make it last asap maybe it will last a couple years give me some time to save money to do the 8.8 correctly!
dartfreak75
Restore it, Dont part it!
So I have a question about the torque converter for the 360.
I know 360s are external balanced so the converter is balanced with the engine.
1st) is the harmonic dampener part of that balance?
I need a new one the original one looks shot to me.
2nd) when I replace the converter how is the best way to balance it to the engine?
I know 360s are external balanced so the converter is balanced with the engine.
1st) is the harmonic dampener part of that balance?
I need a new one the original one looks shot to me.
2nd) when I replace the converter how is the best way to balance it to the engine?
Yes, the harmonic balancer is part of external balance. B&M does sell a balanced flex plate so you don't have to worry about having a weight welded on the TQ converter.
*Edit* The balancer's are keyed, they can only be installed on the crankshaft one way. *Note* Do not lose the key! Easy to do and PITA to find if you dropped it and it bounced it's way to some obscure dark corner of a inter-dimensional portal that somehow formed in your garage.
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nm9stheham
Well-Known Member
for the rear esternal weight, you can either buy a B&M plate that has a bite out of it at the right spot, or weld a weight on the plate or converter at the right spot(s).
Here is the B&M plate for 904/360:
B&M Flexplates 10239
You you can buy separate weights, and tack weld them onto the TC in certain spots. TCI has some info on that but there are better diagrams around.
The damper is a separate imbalanced part for the 360 to provide the correct external balance weight at the front.
Here is the B&M plate for 904/360:
B&M Flexplates 10239
You you can buy separate weights, and tack weld them onto the TC in certain spots. TCI has some info on that but there are better diagrams around.
The damper is a separate imbalanced part for the 360 to provide the correct external balance weight at the front.
dartfreak75
Restore it, Dont part it!
Thanks for the info guys!.
So with the harmonic dampener. How do I go about balancing the new one??
So with the harmonic dampener. How do I go about balancing the new one??
The balancers look something like this:
dartfreak75
Restore it, Dont part it!
mine looks like the one on the bottom! But the seals are all rotted. It has to be replaced.
dartfreak75
Restore it, Dont part it!
Iv seen used and new ones that look like mine do they all balance out the same tho?
They should be the same if they were designed for a 360 with factory external balance.
Late to the party, are you building a 360 or leaving the bottom end alone and just adding cam, intake, and the like,
dartfreak75
Restore it, Dont part it!
I'm building the bottom. I'm having it bored over Hopefully .03 will be enough. I'm using speedpro h116cp pistons they have a ch of 1.660. The goal is to use the lunati voodoo 10200703 cam. I just finished doing some measuring with my heads and they will need some work with that cam so I may have to tweak the plan some. But here is the goal
9.5 cr 360 .30 over
Ported 360 heads
340 cast iron (factory) intake
Holley 600 cfm
Headers dual exhaust.
703 cam here is the card.
It needs about a 2400 stall but that is gonna have to wait.
dartfreak75
Restore it, Dont part it!
Ok so here Is the update on the head measurements I promised.
I measured them in a couple different ways just to make sure I covered it all here is what I got.
The installed height of the spring is 1.64
The max lift height (retainer made contact with the seal) is .490
The max lift without the seal(retainer made contact with the guide) is .615
And the retainer to spring seat when open is 1.16 with the seal and 1.03 without the seal. So doing the math with the seal in place.
1.64-1.16=.480 my book recommends a .100 clearance so my max lift would be .380
That clearance seems a little much to me but that's what is says.
I measured them in a couple different ways just to make sure I covered it all here is what I got.
The installed height of the spring is 1.64
The max lift height (retainer made contact with the seal) is .490
The max lift without the seal(retainer made contact with the guide) is .615
And the retainer to spring seat when open is 1.16 with the seal and 1.03 without the seal. So doing the math with the seal in place.
1.64-1.16=.480 my book recommends a .100 clearance so my max lift would be .380
That clearance seems a little much to me but that's what is says.
nm9stheham
Well-Known Member
You don't... you get one already made. It IS possible to do one yourself with the rigth techniques and data. But even with any perchant for.... mmmmm.... creativity LOL..... I'd just buy one.
WHO CARES? IT'S A FLIPPIN STREET MOTOR. GAWD guy, give it a rest, already. He's buildin a STREET CAR. He doesn't care about every last drop of compression before detonation. He wants to have FUN. How bout you back off for once and let somebody HAVE FUN, ok? The world doesn't revolve around YOUR WANTS.
dartfreak75
Restore it, Dont part it!
Yea I'm gonna buy a new one for sure I thought you had to balance the new one to the engine. Mike straightened me out lol! Thanks
dartfreak75
Restore it, Dont part it!
So what seals do you guys use to get that .127 clearance back? The book I'm reading says you have to machine for new seals what are the choices?
If you're building the bottom end why not just have it balanced. (you should anyway) and then everything will be neutral. (balancer, flex plate and converter.)
??? Valve seals?
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