I have a B18B with Crower 403's, bolt-ons and fuel tuning on a stock block right now, making 148whp/126wtq. I'm thinking about doing a B20 block with 11.0 or so compression, but I'm not sure if the rest of what I have will be up to the task.

With the new block and keeping the stock 6900rpm redline, how badly would I need:
-Head port/polish (stock now... with higher compression, 2.0L and big cams would this be a huge weak link even with stock redline?)
-Bigger header (currently USDM DC 4-2-1... that 2" collector is rather small)
-Bigger cat (currently 2.25" Carsound)
-Bigger/less restrictive exhaust (currently A'pexi WS with 2.36" piping and chambered muffler)
-Bigger TB (currently have stock, but another stock LS TB lying around)
-Fuel pump (stock LS pump is already pushing 47psi as it is!)

How necessary is all this stuff? I want to do the block but won't have enough money to replace all this stuff at the same time... I don't want to spend a ton of money on the block and just see it be completely choked off. Would these parts I have now be super-restrictive or merely a bit short of ideal but not too bad? It seems like all this stuff would be really restrictive to the new block, but I do hear about all those near-stock B20s making great power....

One last thing... I'm looking at ImportBuilder's Econo block. $1500 shipped with new bearings/seals, cleaned and honed, with new pistons, core required. That sounds a bit pricey but #1 on my list is RELIABILITY and I trust IB... is there another shop that is known for QUALITY work that would do it for less? Because $1500 seems good until you realize that they really aren't doing/supplying a whole lot.

Any help is appreciated. Thanks!

 

Dude, honestly if the B20 block is built right clearances are right, aftermarket rods, balanced crank a good block to start with 84.5mm or so sleeve 11:0:1 c/r it should do fine, key is to have it done right but you know that. My setup for my CR/VTEC is B20B block 84.5mm bore, JE 11:0:1 pistons, Eagle Rods, ARP Rod/main/headstuds, cometic head gasket, the 2000 ITR head off my LS/VTEC, new oil pump with prodrive oil pump gear, new GSR water pump, magnafluxed crank balanced crank, clevite main and rod bearings, bored/honed/hot tanked zyglowed block, and absolutely every tolerance and clearance has been checked several times by a pro, new timing belt tensioner, new timing belt and it will spin fine to 8500rpm possibly 9000rpm, a block girdle is a good idea but it really isn't "Necessary" for a street engine several run fine without them my buddys 11 second all motor 2.0L LS/VTEC didn't run one and it was an all out drag car that never saw the street and they never once had an engine problem...it was sleeved...with 14:0:1 IB Wiseco superdupers and other ****...but anyway a setup similar to mine will be fine for your street usage but sleeves are always a good idea however if your talking sleeves don't bother buying a B20 block just sleeve the B18B to 84.5mm and a block girdle and it will be much much stronger, as for the LS head I still don't believe in All motor LS but you've had great success with it and I suggest you keep it up. PM me on sometime on SH0 if you want to get more details

 

Cool thanks. Actually Jeff just sweetened up the deal and included forged rods/pistons in there. So I really really really wanna do it!!!

I'm staying non-VTEC, too much cost/complexity for me with VTEC. I would have to buy a whole lot of new parts (basically start from scratch) if I were to go that route. Plus I love it when people at autocrosses ask me if I have a small turbo setup and I tell them it's not even VTEC haha.

I figure with this setup, I'll be good for ~170whp, 140+wtq, and a broad powerband with big-time midrange - exactly what I want for autocross.

Any thoughts on the restrictions I listed? I don't know what fuel pump to get - I've read that the GS-R stock pump flows far more than the LS one, but I never see people swapping them in - any reason why? I know aftermarket ones are cheap but you can count on stock to work right all the time.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by White98LS &raquo;</TD></TR><TR><TD CLASS="quote">

With the new block and keeping the stock 6900rpm redline, how badly would I need:
-Head port/polish (stock now... with higher compression, 2.0L and big cams would this be a huge weak link even with stock redline?)
-Bigger header (currently USDM DC 4-2-1... that 2" collector is rather small)
-Bigger cat (currently 2.25" Carsound)
-Bigger/less restrictive exhaust (currently A'pexi WS with 2.36" piping and chambered muffler)
-Bigger TB (currently have stock, but another stock LS TB lying around)
-Fuel pump (stock LS pump is already pushing 47psi as it is!)
</TD></TR></TABLE>

Head porting...Good!

Cams...Crower or cranecams

Bigger header...try JDm ITR 4-1(2.5" collector) This what I use

Exhaust... Go 2.5" piping, get a high flow cat and good flowing exhaust!

TB...Maxbore.com, $100 for 62 to 64mm

Fuel pump...stock is fine, I had a Walboro and it was too much for it(I had 55psi on my guage, not good )

 

I've ran a B20 with stock rods and bolts for well over a year shifting at 9500 with no probs.


I would run a DC JDMITR 4.1 and a 70mm t-body. I wouldnt really worry that much about exhaust.
I like the Crane #20's.

Keep up the good work

 

But then you're talking going from a bigger collector to a smaller B-pipe... not good in theory.

I already have the Crower 403s and plan on sticking with em. That's amazing the B20 lasted shifting at 9500!! Good to hear.

 

Just put the bigger flange on that pipe. Its not that big of a deal. Plus the cams that your useing not going to really need that big of an exhaust.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by nonvtecallmotor &raquo;</TD></TR><TR><TD CLASS="quote">I've ran a B20 with stock rods and bolts for well over a year shifting at 9500 with no probs.


I would run a DC JDMITR 4.1 and a 70mm t-body. I wouldnt really worry that much about exhaust.
I like the Crane #20's.

Keep up the good work </TD></TR></TABLE>


70mm TB!?! DAMN!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by hybrid_vtec &raquo;</TD></TR><TR><TD CLASS="quote">


70mm TB!?! DAMN! </TD></TR></TABLE>I've ran it on my other motors and loved it.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by nonvtecallmotor &raquo;</TD></TR><TR><TD CLASS="quote">I've ran it on my other motors and loved it.</TD></TR></TABLE>

I always thought it would be too big! Never tried it so I can not comment!