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Discussion Starter #1
hi!

This winter im going to take out the engine and rebuild it.
The car is a 6spd L98 1991 vette..

Could you give me som feedback on my plans.
This is what im planing to do:

Replace all bearings.
Change the pistons and rods to better once that can handel NOS ( cause thats my plan ).
Im going to internal balance all parts.
Im going to use my hot cam, but a new pair of heads are going to be installd, im running LPE ported 113 heads right now. But im looking at AFR 195 or trick flow heads.
After talking to some engine builders, and reading Jon L. book on "how to modify a SB chevy engine" im going to keep my stock crank. I think it will be good enough for my app. What do YOU think?

NExt question is " compression "? Im not sure on what compression im going to run. The car will se nitrous on the track, ( and i my wallet allow a SC later ) and that is not often so I dont whant to take away to much of the power by lower the comp to much, any ides there?

Im also going to change all bolts to ARP ofcourse.
C 77 bearings ar going to be installed.

Im also going to run a LT1 inakte conversion ( done by me ) on the car, I think that will work good with my 6spd.
And mayby a set of 4:10 gears.

Hooker headers is going in.

My goal is a under 12:5 sec car N/A, and 11 with nitrous. That would leave me in the 400hp range N/A.

I know this is going to be a high rpm setup and will shift the car 6000rpm. I hope the new rods and pistons along with the setup being balanced will take that.

Thanks
 

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if your goal is a 12 second corvette you will reach that goal far easier by upgradeing to a 383 kit, both the longer stroke and the increased displacement will increase your chances of getting there, since your planing on replaceing the heads,rods,bearings,pistons and rings anyway you might as well take FULL ADVANTAGE of the work and get a STROKER CRANK KIT it will only cost a few hundred more and be WELL WORTH IT!
look over these engine combos ESPECIALLY # 11, 15.16,17,and #71

http://www.ryanscarpage.50megs.com/combos1.html

youll want 10:1 compression with that (HOT CAM) and FORGED PISTONS ARE MANDATORY, a cast crank will work ok at that hp level, here youll need this info

http://www.bracketmasters.com/small_block_stroker_383_cu.htm

http://www.strokerkits.com/383.htm

http://www.jegs.com/cgi-bin/ncommerce3/ProductDisplay?prrfnbr=3788&prmenbr=361

keep in mind that theres BOTH ONE AND TWO PIECE REAR SEAL STYLE KITS and BOTH INTERNAL AND EXTERNAL BALLANCED KITS

porting the standard TPI intake will work with serious port work and the nitrous but if you have the skill level to convert an LT1 intake that will work too, the 4.11 rear gears and SLICKS are almost mandatory as are reworking the FULL EXHAUST SYSTEM
 

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Discussion Starter #4
but a lt1 intake will produce more power then a tip even ported?

is the hot cam good enough to make power?
And allmost all the combos you showd me makes power at 6000rpm is it ok to reeve the engine so high?
 

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an LT1 intake can flow more air than a TPI but it does NOT have the runner lenght to build the torque that a STEALTH RAM has COMBINED with that flow, look over this post carefully

http://www.digitalcorvettes.com/forums/showthread.php?s=&threadid=2826

and KEEP FIRMLY IN MIND THAT the LT1 intake does not flow as well or have the runner length of the miniram altho they are both extremely close in design, if you look at the data in that TEST,the STEALTH RAM PROVIDES a better TORQUE CURVE and a BETTER HP PEAK in that test engine,and far out performs a ported TPI with the aftermarket base and large tube runners, now I have run both the miniram and the stealth ram on my 383 engine and at least on that combo, I also got similar results in that the STEALTH RAM NOTICABLY OUT PERFORMED THE MINIRAM, the only problem is that the STANDARD STEALTH RAM intake REQUIRES a hoodscoop to fit under a standard corvette hood, HERES WHERE YOU CAN BUY A CUSTOM STEALTH RAM that WILL FIT UNDER A STOCK CORVETTE HOOD!

http://www.fasterdeals.com/garageindex.html

now as far as cams go, that chevy fast cam is ok, but not the best choice, its designed for a 350 displacement and 1.6 rockers, and does not get you to the engines full potential,the 383 with a STEALTH RAM will benefit from a larger cam, I chose the crane 119661,

http://dab7.cranecams.com/SpecCard/DisplayCatalogCard.asp?PN=119661&B1=Display+Card

several people have had good results with the CROWER #00471

http://www.crower.com/misc/cam_spec/cam_finder.php?part_num=00471&x=45&y=9

HOLLEY used a LUNATI very similar to the lunati # 54756LUN
232°
242°
dur
.510"
.525
lift
110LSA

all three cams require custom tuning and 3.73 or 4.11 rear gears to get the full potential,all three cams when matched to a 11:1 compression 383 AFR 190cc heads and a stealth ram should make well over 450hp and 450ft lbs of tq, my testing and my computer programs all have results or predict close to 470-500hp when correctly tuned for those combos,people reading this not useing a manual transmission like you are ,if running an auto transmission a 3000rpm stall converter will work much better than a stock converter and should be concidered mandatory those cams REQUIRE 11:1 compression pistons to work at full potential in a 383 in the recent hot rod magizine article they made 465hp/458tq with a similar stealth ram combo on a 359 displacement engine, a 383 would have boosted the results by 20hp/20ft lbs on average
and ALL THOSE CAMS WORK VERY WELL IN A 383 11:1 combo IN THE 2500RPM-6000RPM range
and before you ask... no theres no way the combo will work to nearly its full potential or even well unless you match ALL the listed FACTORS correctly built combos require ALL THE PARTS MATCH THE RPM AND AIRFLOW AND HP GOALS
383 displacement
11:1 compression
stealth ram intake
custom tuning
headers
free flow exhaust
AFR 190cc heads
one of those 3 cams
a 3000 stall converter if an auto is used
3.73-4.11 rear gears
150hp NITROUS EFI KIT OPTIONAL BUT RECOMMENDED
 

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Discussion Starter #6
so what you saying is to toss the hotcam and my heads. the same my plans on keep it a 350, and the lt1 intake doesent flow good enough compared to the stealth ram...

What about the stroker kits, should I get the steel crank or can you recomed a "budget" 383 that will work?

And will those cams pass a "sniffer" test?

Thanks
 

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"so what you saying is to toss the hotcam and my heads. the same my plans on keep it a 350, and the lt1 intake doesent flow good enough compared to the stealth ram...
"
NO what I said was that altho the TPI intake or the LT1 intake can be made to work, if your going thru all that trouble the STEALTH RAM is the BETTER CHOICE due to a better combo of flow and potential torque curve

What about the stroker kits, should I get the steel crank or can you recomed a "budget" 383 that will work?

while no one in thier right mind will tell you a cast crank is as strong as a FORGED CRANK, a cast crank will work,at that hp/tq level, its your choice
go to
http://www.flatlanderracing.com/
(Chevrolet Stroker Kits)
(Small Block Engines)
(the SKC38364 kit for $999 if you choose cast or the SKC3836 forged kit for $1259 will be reasonable choices)


And will those cams pass a "sniffer" test?

my engine did pass emmision testing (barely) when we were still testing emmisions in fla. with that CRANE 119661 cam, but thats not in any way saying your engine will even if you stay with the ( HOT CAM) the cylinder seal (RINGS, valve seals, quench,ignition system,true compression ratio,ETC.) and several other factors plus your tuning ability will have a great deal to do with that, the (HOT CAM) is more likely to pass simply because its got a lower overlap/durration
 

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Discussion Starter #8
thanks!

If i look from a budget point of view. Im thinking of reuse my LPE ported 113 heads for now. And save that money to get better internals. I mean you can always swap heads later on.
So a balanced 383 with a stealth ram, the cam you recomend, my 113 heads for now and the stealth ram. Is that a 12 sec car?
 

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while the cars rear gearing, and YOUR ABILITY tuning have a big effect on the results, yes a 383 with 11:1 compression and that cam, the crane 119661, a stealth ram intake and your ported heads should get you into the 12s easily be very sure that you check aLL CLEARANCES CAREFULLY during engine assembly and check this site below for tuning help, you can use some of the info to modify your software efi control data even if your useing the stock ECU/combo, youll need to do some tuning to get everthing running correctly with the changes to the engine, and while the HOLLEY laptop controlable system is easier the stock chevy ECU can be retuned to work ok with the reprogramer kits available

http://www.holley.com/HiOctn/ProdLine/Products/C950/C950A/534-144.html
(Commander 950 Tuning Manual PDF file (9.4 MB)



here read this, just the STEALTH RAM made a very noticable inprovement, but remember youll need the custom stealth ram or a hood scoop to fit the standard stealth ram, under a 1984-1996 corvette hood

http://www.fasterdeals.com/garageindex.html

youll make MORE hp and TORQUE

http://www.gmhightechperformance.com/tech/0307htp_holleystealth/
 
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