please help building a all motor LS

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cage518

New Member
i have a 94 integra, with-
b18b1 block
b18 head(crane cams stage 2,titanium valves and springs)
adj cam gears
spoon chip for ecu
70mm throttle body
obx-r type r style intake manifold
aem cold air intake
headers full 3" stainless catback exhaust
aem light weight pulleys including underdrive pulley
also i am swithing the b20 fuel rail and injectors over to the b18

SO MY QUESTIONS-
1)is it safe to use the p30 b16 pistons in the b18 block and using the stock rods from the ls?will there be any mods required?
2)any suggestions on how to set my cams? intake degrees? exhaust degrees?
3)my buddy told me to use the type r crank combined with the b16 pistons with the ls rods and its like a stroker motor, is this true? if it is would that be safe to do and would there be mods that would have to be made?
 
i have a 94 integra, with-
b18b1 block -- OK
b18 head(crane cams stage 2,titanium valves and springs) -- OK
adj cam gears -- OK
spoon chip for ecu -- get rid of it and get a proper tune done, the skunk2 maps are shit (i had a chip with their map before :thumbsdown: )
70mm throttle body -- not really needed but OK
obx-r type r style intake manifold -- OK
aem cold air intake -- OK
headers full 3" stainless catback exhaust -- too damn big for all motor
aem light weight pulleys including underdrive pulley -- not a fan... but if you want em go ahead and run em
also i am swithing the b20 fuel rail and injectors over to the b18 -- no point


1) yes
2) not sure what ieal would be for those
3) dont bother
 
the frankenstroke kit you got put together wont do big difference but would be cool seen it done better than stock and yea 3 inch is way to big,,, you need back pressure 2 1/4 2 1/2 biggest but the pulleys are cool but ive heard bad things about underdrive pulley never delt with the problem personally but if its a generic underdrive it can cause vibration...
 
Backpressure is BS.

The R crank with the LS rods will probably make the B16 pistons crash into your head. Stick with what you've got.
 
thanks guys

i ended up just buying a brand new fully built block with rods, rings,bearings,high compression pistons and a sleeve job. another question that i have are b20 injectors and fuel rail bigger than that of the b18?????
what size cc injectors do you think i'll be safe with providing the work i have done?(remember it's a completely built motor block to head)????
 
The fuel rail is the same- hell, the head is the same between the B20 and the B18. So are the injectors.

For your build, I would recommend 370cc or 440cc injectors. Make absolutely sure to tune, tune, tune!
 
Calesta said:
The fuel rail is the same- hell, the head is the same between the B20 and the B18. So are the injectors.

For your build, I would recommend 370cc or 440cc injectors. Make absolutely sure to tune, tune, tune!
Click to expand...

really that big injectors? i have 310cc with no issues.
 
You will be fine with b16a pistons on ls rods from what I've read on other forums on this site, as far as the type r crank goes... It will probably perform better but it won't make any type of a "stroker" kit. So is it worth it? You decide, I personally wouldn't spend the money when a stock ls crank is fine. Your 3" exhaust should be fine to back pressure is overrated. The 70mm tb is too big though, stock ls is only 62, so you should probably consider 65 or maybe even 68. I'm gonna start basically the same build soon so I would like to see how this turns out. And don't forget to check clearances running those cams with those pistons.
 
3.) No. GSR/ITR cranks have shorter strokes than LS/B20 so you'll actually be de-stroking the motor and losing a tad bit of torque.

Also, Mike, you got it backwards. GSR/ITR crank combined with LS rods(which are shorter than GSR/ITR rods) not only de-strokes your motor, it'll lower compression a whole lot making the B16 pistons' dome actually useless and just screws up combustion chamber shape. B18C rods on a LS crank would make it crash into the head; though that combination won't work anyways because the B18C rods are too narrow for B18A/B18B journals.

Back pressure was never "rated" to begin with; only incorrectly interpreted. There's an initial pressure front from the pulses, which could be considered back-pressure(really it's a pressure wave), but there's also a negative-pressure wake that follows it. Increased back pressure means this wave will no longer be negative(hence can't take advantage of scavenging effects) and the engine does more work to push the gasses out. Scavenging effects take place with an optimal header design and cam timing; after the header you want as little resistance to flow as possible to let the header do its job well; though you also want the gasses to flow as fast as possible too. It's all a balancing act.

As for injectors; try out CBR injectors or even RDX injectors. There's people with RDX injectors(which are 410cc) that noticed gains simply from better atomization; CBR injectors are the same design but flow less(about 290-310cc IIRC).
 
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Magana559 said:
really that big injectors? i have 310cc with no issues.
Click to expand...

For the power levels I would be tuning for with that setup, I would run that size. :)

K2e2vin said:
Also, Mike, you got it backwards. GSR/ITR crank combined with LS rods(which are shorter than GSR/ITR rods) not only de-strokes your motor, it'll lower compression a whole lot making the B16 pistons' dome actually useless and just screws up combustion chamber shape. B18C rods on a LS crank would make it crash into the head; though that combination won't work anyways because the B18C rods are too narrow for B18A/B18B journals.

Back pressure was never "rated" to begin with; only incorrectly interpreted. There's an initial pressure front from the pulses, which could be considered back-pressure(really it's a pressure wave), but there's also a negative-pressure wake that follows it. Increased back pressure means this wave will no longer be negative(hence can't take advantage of scavenging effects) and the engine does more work to push the gasses out. Scavenging effects take place with an optimal header design and cam timing; after the header you want as little resistance to flow as possible to let the header do its job well; though you also want the gasses to flow as fast as possible too. It's all a balancing act.
Click to expand...

Ah, you're right- I had it backwards.

And as far as backpressure being "overrated" I was more talking about all the misinformation about it. What you really want is smooth laminar flow without turbulence. A variable diameter exhaust would be best. :)
 
Calesta said:
And as far as backpressure being "overrated" I was more talking about all the misinformation about it. What you really want is smooth laminar flow without turbulence. A variable diameter exhaust would be best. :)
Click to expand...

Small to big or big to small? I have 2.5" header outlet/cat to 2.25" exhaust
 
How much power are you pushing? If I was you, I'd match the exhaust diameter to your cat outlet diameter. There's not really much of a point in having the larger collector if you're dumping into a smaller exhaust.
 
how much horsepower ideally will i have????

i want to be in the 300's. the only place around here that tunes is synapse and they are backed up for like a month or two so if i setup today it would be 1 or 2 months from now. is there a way to tune without a dyno? also what chip would you recommend for the ecu? is there a way to post pictures in here?
 
300hp? All motor LS? That would be quite the challenge.
A solution to your ECU situation can be a socketed ECU so a dyno-tuner or street-tuner can program and burn a chip into your ECU.
Its a cheaper way to get good results. Hondata and others are out there too but they can be pretty expensive

Calesta......I just got 2.5" header/cat (I had a 2" header/cat combo before with same exhaust) I see (on ebay) a company makes fab'd pieces of stainless
exhaust piping that are bent for Civics/Integras already and just need to be welded (to muffler/resonator/etc).......hmmm.....but stainless is expensive and I know I want mandrel bends.
 
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cage518 said:
i want to be in the 300's. the only place around here that tunes is synapse and they are backed up for like a month or two so if i setup today it would be 1 or 2 months from now. is there a way to tune without a dyno? also what chip would you recommend for the ecu? is there a way to post pictures in here?
Click to expand...

Yeaaaaaaaah.... 300whp all motor is going to take the best of pretty much everything- tuning, fuel supply, breathing- everything. No chips. Hondata/Uberdata/similar or true standalone. Tune on a dyno AND street tune.

CAFROG said:
Calesta......I just got 2.5" header/cat (I had a 2" header/cat combo before with same exhaust) I see (on ebay) a company makes fab'd pieces of stainless
exhaust piping that are bent for Civics/Integras already and just need to be welded (to muffler/resonator/etc).......hmmm.....but stainless is expensive and I know I want mandrel bends.
Click to expand...

KTeller? That seller is pretty good.
 
300whp on a all motor LS isnt gonna happen. I hit 167 whp.

plus if your gonna run on stock pistons and stock rods your not gonna make more that 200. 200 is pretty hard to reach on a LS head.

Go LS vtec with a gsr head and ctr pistons, see whats the tallest cam you can run without smashing the valves into the pistons. Also your not gonna have any room to play with cam timing so that might restrict you from making more power.

Next thing I would do is Spray. 100 WET shot and call it a day.

Make sure you tune it....if you dont you will blow it all to hell.
 
Calesta said:
How much power are you pushing? If I was you, I'd match the exhaust diameter to your cat outlet diameter. There's not really much of a point in having the larger collector if you're dumping into a smaller exhaust.
Click to expand...

What did you mean by Variable Diameter in the post before??
 
tapers down as you go out, similar to a reverse megaphone, and would help maintain velocity as gasses cool and contract.
 
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