Budget build 6 bolt 4g63t

[1AWD90]

Well I had the mishap of my timming belt tensioner bolt comming lose and my crank being 30 deg. off on my timming. Needless to say it bent every intake valve. Now here is my question. I have never done a cheap budget build always went all out on my motor builds. Well this is my daily driver and driving my lift truck everyday to work is gonna hurt the pocket book on gas mileage. So I was wonder what you guys think I should do? I have a completely redone 6bolt head. Ported and polished 1mm over size stainless valves with stock NA vavles springs all I had laying around at the time to finish the head. Should I use that head or rebuild my old head with the bent valves? Also what should I put in for pistons? This looks like the 2nd time this motor has bent vavles as there are already smiley faces on the exhaust side to. I was thinking evo 9 pistons and use the rest of my rotating assembly.

 

[Oliver@Slowboy]

I would use 2g pistons and your rods/crank obviously new bearings and rings. Put your ported head on it and build the head you take off for whatever you may have been saving you built head for.

 

[1AWD90]

Well the head was actually saved for my 4g63t build thats going into a 94 geo metro. However, that project has been on hold for awhile since I got my new camaro. Anyways whats the advantage to the 2g pistons over the evo 9 I know they are cheaper but are the evo 9 pistons not forged?

 

[ramsack]

Evo IX pistons are partially forged. The top piston "head", which is a stupid term, is forged, and the skirt is cast.

 

[Aproductions]

compression.....on a evo the evo compression is higher but then you look at other factors such at the head gasket and all that stuff and find out only with a certain size head gasket can you get the higher compression.....basically use stock 2g ones.

 

[donniekak]

I have never understood the whole evo/2g piston thing. By the time the rods are reconditioned, the small ends bored, the pistons and rings purchased, you are over half the cost of aftermarket rods, and forged pistons, with stock parts. I would inspect the pistons to make sure the rings rotate freely, and get some rings and bearings, and throw your head on.

Do people forget how many 10 second runs have been made on a stock 1g bottom end?

 

[1AWD90]

I would do that except for the fact that this looks to be the second time these pistons have hit some valves. I would rather be safe then sorry and just replace my pistons and not have to worry about them having weak points.

 

[dsm-onster]

Boring the small end and pressing 2g/evo pistons PLUS spec-ing the big end costs under $200 (the reconditioning is just hottanking and measuring). You didn't have bearing contact, so you're likely going to need ZERO big end honing (measuring by the shop will tell you though). It's not complicated or time consuming, nor takes special equipment any decent machine shop wouldn't have. Add the pistons and you're at about half (or under half) of a decent set of forged pistons/rods at the same CR. Which still need to be spec-ed, and cut if out of it. If you plan on staying under 600whp, this is all you will ever need.

 

[donniekak]

Boring the small end and pressing 2g/evo pistons PLUS spec-ing the big end costs under $200 (the reconditioning is just hottanking and measuring). You didn't have bearing contact, so you're likely going to need ZERO big end honing (measuring by the shop will tell you though). It's not complicated or time consuming, nor takes special equipment any decent machine shop wouldn't have. Add the pistons and you're at about half (or under half) of a decent set of forged pistons/rods at the same CR. Which still need to be spec-ed, and cut if out of it. If you plan on staying under 600whp, this is all you will ever need.

I would never have rods in my hands, and not change the bolts and have them resized. Reconditioned rods are cleaned, checked for twist, small end checked, new bolts, and big end resized. This is the standard procedure at every machine shop i've been to, with the shop i frequent shot peening them also.

With drop in std sized forged pistons, on eagle rods selling for $700 brand new, i'd rather stay totally stock, or upgrade to aftermarket.

The whole upgrade with oem parts sounds to much like honda tech for my taste. I don't really think you can make more power on evo or 2g pistons, than 1g pistons anyway. I believe the stock 1g block record made more power than anyone with evo or 2g pistons on 6 bolt rods.

Just my take on the situation. When it comes down to it, people have different ideas and wants. Any of the above setups will hold good power, some just leave more cash for other mods, like fuel and turbo upgrades.

 

[dsm-onster]

I just think that a stretch gauge over the bolts and checking them are cheap. It doesn't cost me much for the shop I'm by to do it. There is no resizing if the size is right . . . I've had many spec fine after 100K of use but without bearing contact. Bearing contact, you better believe they have been heated enough to distort. I'm not saying not to measure them. But The cost to measure is less than the cost to measure and correct, by far. . . But yes it's all opinion.

The cost of upgrading to 2g pistons isn't for the reliability at higher horsepower. It's for the added compression. EVO pistons are 1CR higher infact. With a turbo car that makes a huge difference. A decent tune really shows the potential of higher compression. It's like "jdm cams" for the b18. They simply are FAR better, if the price is right. . . . . .But that's opinion too. Since you can have any compression you want for $200 more. And have stouter pistons. YET. It's the rods that usually bend on these stock builds pushed to the edge, not the pistons that melt/crack. It's the tune that kills pistons for most of us.

 

[donniekak]

A decent tune really shows the potential of higher compression. )

I run 9:1 pistons on e85. The biggest difference i notice(beside needing much less timing) is the off boost response, it's like an na car.