possible 4g63t rebuild questions

[94exa2]

Hey guys, I am looking for more info on building 4g63 engines. I plan to one day replace my old wore out 4g63 7 bolt with a 6 bolt after i rebuild it, but have some questions on parts to use.

I know i'd like the 6 bolt block over the 7 bolt for less chance of crankwalk, but should i use 6 bolt rods or 7 bolt rods in the 6bolt block (idk if they are even interchangable). should i use 6 bolt or 7 bolt pistons? (if they are interchangable)

basically, which are the best oem parts when rebuilding a 4g63?

6 bolt block
2g head, im, em, arp headstuds
____ oem crank?
____ oem rods? with arp bolts
____ oem pistons?

 

[BogusSVO]

build the 6 bolt as the 6 bolt

yes you can use 7 bolt pistons on the 6 bolt rods, but the wrist pin hole in the 6 bolt rods has to be machined lager by 1mm to accept the larger 7 bolt wrist pins.

the OE crank will be fine, as long as it is in good shape.

the 7 bolt head, will need the head bolt holes macined larger, 6 bolt has 12mm head bolts a 7 bolt has 11mm head bolts.

http://www.dsmtuners.com/forums/cylinder-head-short-block/341885-oil-port-mod-2-4g63t.html

what is your goals for the car?
what HP do you want the engine?
what is your budget?

 

[g4ebguy90]

a 6 bolt...

6 bolt rods with ARP rod bolts.
2g pistons and have the 1g 6 bolt rods machined to fit them right.

Thats the way I would go.

 

[BogusSVO]

I do not really see the point in doing the 2g pistons on the 1g rods... looks like more cash outlay than the increase in power

a stock 6bolt is what? 8.8 : 1 ratio ? and the 7 bolt piston swap is 9.1 :1 ? so a .3 gain in compression? for about a extra $100

that would trasnlate into what a base 1-2 hp and torque increase?

I would rather spend that money or put it towards something more useful.. such as a tune device (DSM Link) wideband o2, head studs forged pistons....

 

[romeen]

I do not really see the point in doing the 2g pistons on the 1g rods... looks like more cash outlay than the increase in power

a stock 6bolt is what? 8.8 : 1 ratio ? and the 7 bolt piston swap is 9.1 :1 ? so a .3 gain in compression? for about a extra $100

that would trasnlate into what a base 1-2 hp and torque increase?

I would rather spend that money or put it towards something more useful.. such as a tune device (DSM Link) wideband o2, head studs forged pistons....

6 bolt is 7.8:1, 2G is 8.5:1

The 2G pistons are supposed to be stronger too. I'm not recommending one or the other but just possibly useful info.

 

[94exa2]

guess ill do 6 bolt block with 6 bolt rods and pistons, acl main/rod bearings, ported 7 bolt head with arp headstuds and ported 7bolt intake mani....thanx guys!

 

[94exa2]

...or would the 1g intake manifold/throttle body be an upgrade of the 2g intake mani and tb?

 

[bryanwheat]

Keep the intake matched to the head that you are using. The ports are different sizes and it will cause turbulence in the intake. Also 2g pistons are somewhat stronger. The ring lands are a few mm lower on the 2g piston so there is less of a chance of damaging the ring lands due to detonation. For what it's worth i'd just go with some nippon coated 6 bolt pistons. You can get them with rings from mizzumo on ebay for like 90 with rings. Also how many miles are on your 7 bolt? You would be surprised to know that it might be in better condition than you think. If it has good compression and no bearing problems i wouldn't pull it apart.

 

[92AWDHX40]

I would keep the intake for your engine, not much to gain there.

 

[94exa2]

so 6 bolt block, crank, rods, pistons...
ported 2g head, ported 2g intake mani and 1g throttle body?

 

[94exa2]

how much hp/tq can a stock rebuilt 6bolt block handle?

 

[LiquidX]

All depends on the tune and other factors. Try searching around for some of the companies that have done stock block records to see what they have managed.

 

[94exa2]

so 6 bolt block, crank, rods, pistons...
ported 2g head, ported 2g intake mani and 1g throttle body, 2g tb elbow?

????

 

[RamenPride]

2G pistons, new rings and bearings, re-use everything else as long as they're in good shape