rattle under acceleration and deiseling when turned off.

[bear351c 10,273]

Could try ACL or a speed shop......

 

http://www.aclperformance.com.au/prod_g_copper.htm

[LJDB 103]

i used a thing called a head saver shim. you use that and 1 headgasket, holmar spay the shim to the block and head gasket on top. seems to be holding up atm. mines a mild alloy head xflow with bout 10.3 comp still in it and timing locked at 30, using 98 octane.

[unfamilia 1,938]

Cool where do you get these shims/decompression plates from.

acl dont list copper for the iron head crossy

[Clevo120Y 815]

Why not just find a good secondhand XD alloy head and manifold, if your head has been shaved heaps to get the comp up then swapping to a stock head will bring your comp down to a manageable level, plus alloy heads are less prone to pinging.

[unfamilia 1,938]

Im thinking of similar options. Even a whole stockish 250xflow. I dont need mods on this thing just a runner. A stock iron head would be better for me so I dont need to stuff around with manifolds etc. Bolt on and off.

[Mixalis 266]

Got a similar set up on mine, flat top hypertechs on an iron head crossy, if you punch the numbers into a compression calculator you'll see that we are running pretty big compression. I have already gone thru one head gasket  running base timing at around 12 degrees from memory on 98 in hot weather. And I've got a mild cam in it as well so same recipe for disaster, unfortunately engine is together and way too late to change so have to make do with what i have. At the moment I'm trying to solve the pinging issue what i have found is the locking the timing at 8 degrees (removing vacuum advance) really makes it work well up till around 4000-4500rpm. I haven't tried bumping the timing up to fill the gap up top but I'm sure there is room for it as the timing is set really low now. Also just bought the wynns version of the nylon octane booster, i.e. same 70 point booster that should bump 98 octane to 100 and hopefully that will solve some of my problems for now. Need to get it on a dyno tho to get proper indications but from what you've said so far definitely bin the 95 it will not work, 98 minimum octane booster if needed. Also removing the vacuum advance leaving the timing to naturally advance as the engine revs seems to have made it behave much better, but yeh i think thats all a debatable topic until you try a few things out. Let us know how you go and what you test out!

[unfamilia 1,938]

Cheers will test over weekend hopefully

[unfamilia 1,938]

Ok 95 out 98 in and fired up straight away. Rattle noticbly better (less) so retatded timing then timing light globe blew at 6 btdc. I test drove much better so retarded by feel slightly and better again. Retarded a bit more Idle got choppy. So maybe a bit more 98 and will see as only had 5lt jerry can.

 

Better plugs and an elec dizzy may be ok to get out and about. A bit better carb for breathing and would be better again. Not happy gotta use 98 as sort of defeats a camper wagon lol. No 98 out bush

Parts hauler it is I guess.

 

cheers for all the help folks.

[Crazy2287 1,886]

Fk it, Slip a grumpy cam in and run the bitch on ethanol.

[unfamilia 1,938]

Ethanol eats out carb seals and lines doesnt it?

Lets get some toulene ;-)

[ando76 4,354]

just add a bit of Castrol M to your E85 my friend.  lubricates the needle and seat and not bad as a bit of upper cylinder lube to.  It's just a way cheaper version of castor oil and it smells soooo good when its burnt.  I run it in my Methanol.  Yes I love that smell way to much and need to get out more.....

[unfamilia 1,938]

E85 in carbs???? Doesnt it eat fuel hose and pump diaphrams, carb seals etc?

Castrol m?

[nos2 751]

Doesn't eat as such.. It cleans.

[Crazy2287 1,886]

It cleans and can dry out older rubbers. The additive should keep everything lubricated. Your fuel hoses need to be SAE30R9 spec and for submerged hose SAE30R10 It can cause corrosion in steel fuel lines and tanks if the water content gets too high so put your filter in the engine bay between the hardline and the pump and start ignoring your fuel level gauge as it wont read ethanol correctly.

[unfamilia 1,938]

Its not reading accurate anyway. Was looking at aftermarket manual ones now too for fuel Gauges.

 

I dont have a submerged line any more. Running a xf efi tank so pick up is at bottom of tank now. Much better.

 

Whats the Castrol m additive and where to get it?

 

Any mods needed on stock carb or fuel pump so e85 compatible

[gerg 10,871]

Running e85 in a carby car means using a dedicated carby that's set up for it: ie bigger jets, squirters, power valve channels and idle feeds. Much easier with an aftermarket efi setup where you just flick to a different map for each type of fuel when required.

[unfamilia 1,938]

Looks like a stock engine will go in then cause not all country towns will stock 98 ;-)

[PRO250 1,506]

Some good reading in here (feel the cast head hate) 

i never knew you could get comp out of a 250 cast engine. ive got on in the shed 10cc pistons head milled to death and not making as much as i would have liked when i built it many moons ago

where you live mate that there is no 98? im in the sticks a bit and almost all places sell 98 as my ute is high in its comp and will not run very well on anything and runs on like a mofo on 91

id go get a XE head and bang it on if you have not rattled the engine to death allready

[unfamilia 1,938]

I'm in the city. Havent rattled it do death at all. Running well as soon as there was rattle I backed off

 

heaps of 98 around but im sure the time I Need it servo wont have it.

[ando76 4,354]

Castrol M can be bought at most decent oil retailers - i.e. you wont find it at supercrap.  You only need it if running alcohol and like gerg said you need to modify the carb to suit it. 

 

I'd concentrate on solving the comp/ timing issue on yours before I worried about modifying the carb. 

[gerg 10,871]

Dunno why there are haters of cast heads. They're bulletproof motors and the majority of those running Clevos have to "put up" with them. Just because alloy is better doesn't mean cast is shit.

[bear351c 10,273]

Exactly.^^^^^

[TF_250 398]

Also try simply changing the spark plug heat range colder, stock replacement plugs are way to hot for any form of modified crossflow go al least two colder

[bear351c 10,273]

From memory, Bosch number goes up for hotter, NGK goes down. Then again, I drink a fair bit..............