ok build questions

JNasty

i drive fast cars (supra)
Jun 25, 2005
358
0
0
41
Jacksonville fl
I have sat here all day reading, and still cant find out a few things. I saw that after the machine work you need to lap the block (do you lap the head as well)? also how do you lap something lol I have no idea how to do that? One of my friends that builds drag cars told me that I didn’t need to do it just put glue on the hg, I assume he’s talking about permatex. but i figure he is full of shit. i had 10 thousands taken off the block but there is still a few blemishes in the deck! the machinist said its prolly just where the anti freeze settled and it wont hurt anything but to get the hg and bring it to him and he will tell me if he needs to machine it some more, but that brings on another problem cant buy the hg until the machine work is done cause i need to know the size of hg to get. I have je pistons and they are 20 over as far as the holes on the hg go "well put it this way how do i make the hg fit perfectly to everything else"?also on the pistons are the je pistons a higher compression piston? I was reading and saw that the front timing cover needs to be machined with the deck how can i make sure this was done? He is in the process of grinding the crank now so how will i know what size bearings and thrust washers to get? in side the water jackets is there anything that can be hurt if i clean out the rust by scraping around with a screw driver? im sure by the end of this thread ill think of some more stuff to ask, i like to make sure everything is perfect cause if your going to do something do it right the first time.
 

pimptrizkit

thread killer
Dec 22, 2005
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vancouver Wa
lapping the block is more of a thing they do when they dont have their block decked or surfaced,

i tried my best to do it, and failed misserbly. i spent about 1200 running around screwing things up. well atleast it felt like

take some pictures of the block deck showin us the blemish you talk about..

most mhg seal fin with a 25ra on them. but the lower the ra the better. some people can have there's done to 5-10 and have a mirrow like finish. 25ra is roughly what the side's of the crank look like but with out any edges , just smooth.

make sure the head is surfaced as well, to the same spec,

your going to want to get a 2.mm mhg to keep your compression around stock, a 1.5 mm might be perfect stock cr but then again may also be higher depening on how much head material was removed.

dont spray any thing on the mhg for installtion.

use brake clean to insure the blcok and head surface are clean.

remember to make sure the dowel pins in the block are there before the head goes back on.


i belive je pistons are stock compression ratio. it's the weisco that are 9.0-1 i belive...
 

JNasty

i drive fast cars (supra)
Jun 25, 2005
358
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41
Jacksonville fl
isn building a little more compression a good thing though. and how do i know what the ra is on my moror i sprayed some wd-40 on the deck to keep it from rustin durint this process is that ok ill get the pics in a bit
 

pimptrizkit

thread killer
Dec 22, 2005
1,572
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vancouver Wa
wd-40 is fine

by eye is impossible really. you need a special machine that reads the roughness average. some machine shopws have them, other's dont, i dont belive mine has one, but he's quite experienced
p9140026xw3.jpg


there's an alright pic of a surfaced block..

higher compression only helps off boost, and more compression means worse gasmillage while off boost, and less achivble boost.
 

JNasty

i drive fast cars (supra)
Jun 25, 2005
358
0
0
41
Jacksonville fl
what do you think about the pics it looks rusty but thats the dirt i cleaned out of the water jackets sticking to the wd-40
 

pimptrizkit

thread killer
Dec 22, 2005
1,572
0
0
vancouver Wa
every thing looks good cept for the last one by cylinder 6, that would be the one im worried about. can you put a straight edge on it and measure how much of a drop that is..

altho that looks like it is in the reign of a coolant passage, if you have you a head gasket see if you can check to see if it will hurt sealing..