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Discussion Starter #1
Hey so this is my first build and I'm trying to do it right the first time.
I'm building a 383 stroker for my 1986 Z28. Heres what I have

L98 block bored .030 over
Stroker assembly from enginekits.com
crank stroke 3.75
5.7 forged rods
12cc dished pistons
splayed main caps
novi 1000 with 10-11lbs pulley
1.6 crane gold rockers
hardened pushrods (stock length)

So with 64cc chambers the compression ratio should be 10.2:1 :yikes:

I know thats way too high to run 10psi so I want to know what size chambers should I be looking for 68cc, 72cc or..... size runners 190cc or 210cc?

Also what size cam? I want it to be a hydraulic roller cam.

I was thinking and airgap intake

btw it is a carbed motor. Unsure on carb setup aswell.

All help would be really appreciated. :beer:
 
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Obamanos
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That is prefect compression for boost.
 

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Discussion Starter #3
That is prefect compression for boost.

I've been told from just about everyone 9:1 or 8:0:1 is the better compression ratios to go with.


why is it you think 10.2:1 compression is good for 10lbs of boost????
 

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Obamanos
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I've been told from just about everyone 9:1 or 8:0:1 is the better compression ratios to go with.


why is it you think 10.2:1 compression is good for 10lbs of boost????
Because it will make more power! That low compression shit is a myth hell my bikes are over 12.1 and they have no problem with boost.
 

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Discussion Starter #5
would i be able to run 91 pump gas?
 

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5th Gear
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With those internals you should be good with that compression, if you're really worried throw it on E85 and back off the timing.
 

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Discussion Starter #7
Carb size?
cam size? I was looking at the extreme energy cam 1,800- 5,800
Intake .510
Exhause .540
230int/244exh
those numbers are for factory 1.5 rockers and I'm going to be using 1.6
 

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Chipotle is my life.
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Im at 9.8:1 on stock internals and have would have no problem with running 91 if i had a baller ass ignition system. You do need to watch out for detonation. If it does do that you will need to back the timing out like Conner said and use something like E85.

Question for Art though, what fuel do you use in your boosted bikes? Higher than 91, mix or something like methanol?
 

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Discussion Starter #9
Conner?? Hey bro Its Gage
 

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Chipotle is my life.
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Sorry i was talking about cwsly's (Conner) comment.
 

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Discussion Starter #11
Sorry i was talking about cwsly's (Conner) comment.
Yea I saw lol my bad man Conner is one of the guys in the group, havent seen him in a few weeks but yea.

But I do see what your saying about timing. I want this car car to run on 91 oct. E85 is kind of scarse around here.
 

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5th Gear
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Lol what's going on bro. I don't know much about carb setups or LT based motors, but from what I see on LS motors you should be able to do quite a bit bigger cam than that, and I would definitely go bigger just because you're doing a blower setup. On an equivalent LS motor with a similar setup I'd be going with something like a 228r which is 228/228 588/588 and probably go with a 110 or 112 lobe separation angle. You'd get a raunchy as hell idle, and the lower LSA you'd still have good bottom end, and the cam is big enough that you wouldn't be giving up much top end, but what you do give up will be made up for tenfold by the blower.
 

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Warp Drive
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But I do see what your saying about timing. I want this car car to run on 91 oct. E85 is kind of scarse around here.
Get a good methanol system and run that to and you'll be fine. Some people mix it with water some run it 100%.
 

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You don't want that kind of LSA with a blower it won't make boost until the redline, and good blower cam will not give the "raunchy as hell idle"
 

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5th Gear
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How does the cam have anything to do with boost on a blower? It's belt driven and from everything I've seen on places like LS1tech you want a good sized cam with a low LSA for a blower. Honest question
 

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Obamanos
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Im at 9.8:1 on stock internals and have would have no problem with running 91 if i had a baller ass ignition system. You do need to watch out for detonation. If it does do that you will need to back the timing out like Conner said and use something like E85.

Question for Art though, what fuel do you use in your boosted bikes? Higher than 91, mix or something like methanol?
The first one was e85 this one is pump 91
 

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Discussion Starter #17
Cam Style:Hydraulic roller tappet

Basic Operating RPM Range:1,800-5,800

Intake Duration at 050 inch Lift:230

Exhaust Duration at 050 inch Lift:244

Duration at 050 inch Lift:230 int./244 exh.

Advertised Intake Duration:290

Advertised Exhaust Duration:307

Advertised Duration:290 int./307 exh.

Intake Valve Lift with Factory Rocker Arm Ratio:0.510 in.

Exhaust Valve Lift with Factory Rocker Arm Ratio:0.540 in.

Valve Lift with Factory Rocker Arm Ratio:0.510 int./0.540 exh.

Lobe Separation (degrees):112

Computer-Controlled Compatible:No

Grind Number:LT1 290HR-12





Keep in mind these are with 1.5 rocker arms Im gonna be using 1.6 rockers.

Also another question I know I need a blow thru carb but what cfm for this elevation???


And Conner, When I get all the parts your more then welcome to help out with putting this monster together :beer:
 

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The Matco Man
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Call comp tech line and give them your set-up: comp ratio, heads, weight of car, etc.. and they will give you your best options. Go with the bigger head option 210 cc and a 76 cc combustion chamber. If you lower the comp ratio you will have more room for higher boost numbers. Why did u go with a 5/7 rod when you could have gone with the 6 inch rod and had better rod stroke. Are you going to stay hyd roller on the l98?
 

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Obamanos
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Call comp tech line and give them your set-up: comp ratio, heads, weight of car, etc.. and they will give you your best options. Go with the bigger head option 210 cc and a 76 cc combustion chamber. If you lower the comp ratio you will have more room for higher boost numbers. Why did u go with a 5/7 rod when you could have gone with the 6 inch rod and had better rod stroke. Are you going to stay hyd roller on the l98?
Why run lower compression to just have to run more boost to make the same power? Boost=heat. Run lower boost with higher compression and make the same power as low compression and high boost. But have way better off boost driveabilty
 

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Obamanos
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And as far as the carb. Call up CSU tell them what you got and they will send you a carb ready to bolt on.
 
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