Engine Buildup for S/C

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Still_Good

Junior Member
This summer I'm looking into building an Integra for use in autocross/tight course applications.

I want to do an LSVtec setup, basic B18B bottom with a B18C head.
Forged Pistons and Rods, not sure what CR. Supercharged, probably a Jackson Racing unit, with 12psi pulleys.

I'd like some clarification/help on the following points:

How high this kind of setup can rev is always debated, and lack of oil squirters is commonly cited as a reason for having a lower rev limit, usually the 7800-8200 range is recommended -- How much is this because of a lack of oil squirters vs. stock rods? Would I even want to spin it faster when mated to a roots type charger?

Can anyone with experience with S/C's give me some advice on comp ratio? I know the JR kit is made a for a GSR at 10:1, would I be anywhere near the mechanical detonation limit on pump 92 with 11:1 pistons? They supply a hondata ECU with the kit, will the VE tables be all wrong with a 1 point variance in compression? Would I be better off getting a real good standalone like the AEM's EMS and tuning it myself?

I want to use 11:1, 40 over pistons, with this setup at 12psi on JR's S/C, what kind of power can I conservatively expect?

Any input is appreciated.
I'm sure some of the questions are noob, but I really do know what I'm talking about, just not on Hondas.

Thanks
Zak
 
if you do do it, the hondata map will be off, yes.. you'll need to get re-tuned.... and you'll need a 3-bar map sensor as well to hit 12 psi. 11 is the limit of the oem map.


tight course? thats WAY too much power.
you'll be better off with just the stock b18c in there.
any more than that, and you'll be fighting traction more than anything, and it will probably just end up slowing you down.


seriously.

build the ls vtec with 11:1 JDM ITR pistons, or p30 b16a pistons if you want to use the stock LS rods. get it on the road with a nice LSD tranny.
drive it at an event.

then, come back and thank me when i saved you 5k on parts. :)
 
Originally posted by pissedoffsol@May 12 2005, 08:50 AM
thats WAY too much power.

seriously.

build the ls vtec with 11:1 JDM ITR pistons, or p30 b16a pistons if you want to use the stock LS rods. get it on the road with a nice LSD tranny.
drive it at an event.

then, come back and thank me when i saved you 5k on parts. :)
[post=498288]Quoted post[/post]​


As cocky as the guy is, when he's right, he's right. :)

You are talking about WAY to much power for a tight technical track. Also, a s/c is better than a turbo for autocross, but still nothing compared to a nice all motor setup.

The setup Brian listed above is exactly what you want for road racing. I am running a very similar setup in my SI. Except I would chuck the LS rods and go aftermarket. And I am running the CTR pistons with a thicker headgasket to put my cr @ 11.7:1 Not to mention all motor is going to be way cheaper for you. Just make sure you get a good ems and you'll be set. :thumbsup:
 
Thanks for the input.

The reason for the induction choice is actually born of my past experience autocrossing my two integra gsrs..

While they were both okay, there was a serious problem with low end grunt.. throwing it in first through a really tight bit (like a box, y'know the half box w/ a cone in it that you come at all lined up wrong) you just get mass understeer and in second at 3800rpms on a b18c theres just nothing there.. so you get a big ole' bog.

I do want the car to be able to hold its own elsewhere -- at least 13.5 in the qtr, and enough power to not be slow-as-hell on the front straight at most courses...

Would a N/A lsvtec build actually have the grunt I'm looking for?
 
If low end grunt is what you are looking for, then a nice medium build in a B20/VTEC will be your best bang for the buck. Some guy on here just posted his dyno chart from his mildly built B20/Vtec and he put down 230 something hp and over 170 pound feet of torque. That is more than enough to spin the wheels through 3rd at almost any rpm in a gutted EK.

I'm not sure what compression the aforemention individual is running or what cams, but I would expect to see around 210-220 wheel hp and 160-170 lb feet on a b20/vtec with around 11:1 c/r and some 3/4 race cam, ie. the skunk 2 stage 2, crower 403, comp 57300, any IB spec or rocket cam.

P.S. - The B20 cylinder sleeves are notoriously weak so I would look into sleeving the block and punching it out to 85 mm. :thumbsup:
 
Originally posted by sohcslammer+May 13 2005, 01:16 AM-->
If low end grunt is what you are looking for, then a nice medium build in a B20/VTEC will be your best bang for the buck. Some guy on here just posted his dyno chart from his mildly built B20/Vtec and he put down 230 something hp and over 170 pound feet of torque. That is more than enough to spin the wheels through 3rd at almost any rpm in a gutted EK.
[post=498732]Quoted post[/post]​

Yes, that's a good amount of power, but that's not typical for a mild B20/VTEC build.

Originally posted by sohcslammer@May 13 2005, 01:16 AM
I'm not sure what compression the aforemention individual is running or what cams, but I would expect to see around 210-220 wheel hp and 160-170 lb feet on a b20/vtec with around 11:1 c/r and some 3/4 race cam, ie. the skunk 2 stage 2, crower 403, comp 57300, any IB spec or rocket cam.
[post=498732]Quoted post[/post]​


I wouldn't expect anywhere near that much torque with that setup- maybe 150-160ftlb at the wheels at the most, especially on 92 octane.

sohcslammer
@May 13 2005, 01:16 AM
P.S. - The B20 cylinder sleeves are notoriously weak so I would look into sleeving the block and punching it out to 85 mm. :thumbsup:
[post=498732]Quoted post[/post]​


Wrong. The B20 sleeves will handle plenty of abuse in an all motor setup. There's no reason to sleeve the engine for an all motor application- just bore out to 84.5mm if you need to clean it up and you're good to go. If someone's willing to spend the money resleeving a block, there's no need to waste the extra $400 on the B20 block just to get the stamp on the front of the block.

-----

On oil squirters- you really don't need them if you run forged pistons. The squirters are nice for the stock cast pistons, but decent aftermarket forged slugs can handle the extra abuse without breaking a sweat, especially if you thermal coat them. The squirters just add windage loss anyway- don't worry about them.
 
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