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Compression
1916baja - February 1st, 2011 at 06:06 AM

Hey guys, sorry about all the questions....

Just wondering where the compression should be set for a fairly mild 2276 drag motor. these are the specs.

REBUILT unleaded heads
silicone bronze guides
42mm intake valves and 37.5mm exhaust valves
3 angle valve grind on intake and exhaust seats WITH a s.i blend
solid shaft rockers
chromolly push rods
94mm pistons and cylinders
NEW rings
NEW wrist pins and clips
8 brand new push rod tubes
forged chromoly 82mm crankshaft 8 doweled
REBUILT and balanced set of German connecting rods
Resurfaced and balanced flywheel 8 doweled and lightened to 12.5lbs
chromolly gland nut
Hi Performance cam with .390 lift and 298 duration (i have been told the he puts in a 110 cam but am seeing if he'll use a 130 or so instead.)
Brand new hi volume Oil pump
8 Rebuilt lifters
All gaskets and seals brand new through out the longblock
New double lipped Silicone rear main seal
BRAND new main rod and cam bearings
REBUILT case with case savors, alignbored, realigned cam journal and stroker relieved

thanks
Mick.


SuperOwen - February 1st, 2011 at 07:38 AM

You have to decide what camshaft and fuel your using, more cam duration and better fuel means more comp can be run.


Craig Torrens - February 1st, 2011 at 07:57 AM

you refer to "he" so I'm assuming you have someone building this motor for you ?


matberry - February 1st, 2011 at 07:59 AM

Yep, cam, deck and head cc's required for this decision to be meaningful. (technically flow figures of heads too)


dragvw2180 - February 1st, 2011 at 09:24 AM

Wedgemate the crank


fish26 - February 9th, 2011 at 05:04 PM

that 298* .390" lift sounds like fk-8, not a bad cam with the right heads and 1.4 rockers, like mentioned before make sure you know all the relevant specs as well as cam duration @.050, good luck with the build show us some photos of the heads, there's a lot of HP hidden in there.


vw54 - February 9th, 2011 at 05:10 PM

how fast and reliable do u want to go ???


1916baja - February 9th, 2011 at 09:08 PM

Looks like that engine fell through at this stage, it is actually a longblock. pricewise it was too good to be true. I'm still on the look out.


Craig Torrens - February 9th, 2011 at 10:51 PM

Quote:
Originally posted by 1916baja
. pricewise it was too good to be true.


Cheap performance motors = BANG !


matberry - February 9th, 2011 at 11:01 PM

Cheap performance motors = cheap parts.....maybe?>*&^%$#%^???????????????????????? Too many questions!!


fish26 - February 10th, 2011 at 09:34 AM

Quote:
Originally posted by Craig Torrens
Quote:
Originally posted by 1916baja
. pricewise it was too good to be true.


Cheap performance motors = BANG !



LOL sooooo true,
unless you build it yourself and know what you're doing.


westi - February 13th, 2011 at 06:16 AM

yes and no boy's.
china crank still kickin in the junka,same goes for the rod's ,pistons.heads well there still on..

it were up to me i would buy a kit from cb performance.and get someone with some intellegence to but it together.


matberry - February 13th, 2011 at 08:23 AM

Yeah, some China bits are fine....... but you do need to check EVERYTHING.

A 2442 build I have on at the moment is using a few top of the line Chinese and this is what we have to fix.
2x rods have the little end bush set with .010" out of true with the crank meanining the pin and piston are .010" crooked in the bore also making the deck ht .010 out pin side to pin side
Out of the two other straight rods one is .003" shorter than the other

To fix this 3 rods get new pin bushes, no biggy

The pistons also look nice, good finish, very light low drag construction, just one has the pin height .005" higher than the rest, probably swarf or something in the machine when it was made... no biggy, just machine .005" off the other three pistons......:starhit: