Gertrude - 2F high performance rebuild (1 Viewer)
- Thread starter andrewfarmer
- Start date
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so is an opne chamber or a closed chamber better??
Also, andrew and Mark, what is the best cam you have found for the hipo 2F's...
I can power through the clutch in my cruiser (it is very new) and I don't want to have that problem in the 60..
Also, andrew and Mark, what is the best cam you have found for the hipo 2F's...
I can power through the clutch in my cruiser (it is very new) and I don't want to have that problem in the 60..
mace i dont think open or closed is really better than the other for what we're doing. its really all in the volume of the chamber. closed runs a flat top piston where open runs a crown. same kinds of compression are obtained either way and if the system is designed properly, velocity and feed are fine either way. nothin wrong with open cylinders, 650 HP has been built with open.
cams?? what do you want?? torque or HP?? i think downey may have the better over the counter cams out there. but i havent really dived into everything.
also, mark and andrew i'm interested if you have messed with or given thought to lump ports?? i have been looking at my head while i'm shaping and porting, the bottom of the runners are a little flat and i wonder if small lumps would make a big difference?
cams?? what do you want?? torque or HP?? i think downey may have the better over the counter cams out there. but i havent really dived into everything.
also, mark and andrew i'm interested if you have messed with or given thought to lump ports?? i have been looking at my head while i'm shaping and porting, the bottom of the runners are a little flat and i wonder if small lumps would make a big difference?
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sorry, not cam. I meant clutch.. Don't know HTF I managed to put cam in there.
I'll have to check out the spare 2F's that I have running around (78 and 86 or so)
One has a head that was recently went through. I bet I could have a bit of fun with that
I'll have to check out the spare 2F's that I have running around (78 and 86 or so)
One has a head that was recently went through. I bet I could have a bit of fun with that
- Thread starter
- #25
Mace said:
I just went to my brake and clutch guy and told him I wanted one that would take a 4000rpm dump (repeatedly).
I've always had my clutch linings bonded as well as rivited since elary days racing when I shredded a couple.
You could always get a twinplate made up if you are having bad problems.
Not sure what the clamp on my p/plate is but I'd say it's about double a std one (from the muscles on my left thigh
)
- Thread starter
- #26
RHINO said:
For LPG, closed is a better shape (due to burn speed).
The open/dome option is easier to get more compression from with a 2F block/F head combo
I was aiming for 11:1 but just couldn't get there with the closed chamber. But here in NZ we never got the open/dome option so I had to used closed.
- Thread starter
- #27
RHINO said:
Don't know sorry - I have a nice man who does that stuff for me so I don't have to worry too much about the details
has it been dyno'ed?
- Thread starter
- #29
bad_religion_au said:
Yes but only for tuning (dyno not accurately calibrated) so didn't note the result.
I did notice from the 1.5F with cam, headers (dyno'd) to this build (dyno'd) I had to open up the main mixing valve for the LPG by about 5 turns, and got approx 40% more power as a result.
I keep meaning to get it done - may have to soon, I'm lloking to install a fully programmable ignition controller...
dmaddox
SILVER Star
2F rules......
hell, I ran an entire shop rag through mine, it went the route of #5. Ran it all season. Still runs like a champ.
2F, yup.
Ragman
hell, I ran an entire shop rag through mine, it went the route of #5. Ran it all season. Still runs like a champ.
2F, yup.
Ragman
andrewfarmer said:
i forget your running LPG, it would really be nice to get that compression up a little more, you can have material added to the combustion chamber for this, but you dont want to reduce to much less that about 67cc's.
- Thread starter
- #32
RHINO said:
With the closed chamber, and to get flow, I've already had to remove some material. Don't want to start adding it!
Maybe I need a turbo...
RUSH55
SILVER Star
On your summary sheet it says you have a modified cam. Can you elaborate?Also, where are you running your timing?
im building up a 2f in the near future, and i was just wonder about raising the compression to about 9 to 1 and running a better cam, is there a way to find out how much i need to mill off the block and head to get a 9 to 1 or should i just go with the specs you used?
is there anything else i should do if i mill the block and head down?
what are some of the draw backs from doing so?
is there anything else i should do if i mill the block and head down?
what are some of the draw backs from doing so?
- Thread starter
- #35
RUSH55 said:
cam 212 duration, .44 lift at valves.
I just went to my cam shop and told them what I wanted the motor to do and they did a custom grind for me.
Timing is currently set to 15 degrees at 500rpm
- Thread starter
- #36
FJ40onNOS said:
Depends on what you've got - flat psitons or domed?
An 'F' head will raise compression some with no other work (but match piston type).
Apart from that, you need to check what may have already been taken off.
Best way is to get your machine shop to cc the combustion chamber and work from there.
If your otal shave is too much you'll need to shorten the locating dowels or the head wont bolt down prorperly.
Pros = more power
Cons = higer octane petrol
andrewfarmer said:
Best way is to get your machine shop to "cc" the combustion chamber and work from there.
"cc", what you mean by cc
RUSH55
SILVER Star
Cubic centimeters. That's how they measure the liquid used in the head blueprinting process. Am I right?
RUSH55 said:
ok ill get on the phones after thanksday
- Thread starter
- #40
bad_religion_au said:
Just had it on today (replaced the LPG regulator).
Got up to 218hp (at 4500) - but it had a bit more in it but it was getting too hot - the cooling fan they had wasnt high enough to cool the radiator
