grumpyvette

itS BEEN MY EXPERIANCE THAT ,if your ignitions functioning correctly youll rarely see any improvements over what a .042-.045 gap provides in an N/A engine application, TIGHTER OR WIDER GAPS CAN AND AT TIMES DO CAUSE PROBLEMS OR LOWER POWER, in theory the larger gap requires a good deal more voltage and the ignition may become difficult at high rpms, lower gaps don,t get the cylinder lit off as effectively at times, keep in mind at 6000rpm the cylinder fills, is compressed and needs to fire and burn in well under 25-30 degrees of piston movement in the 720 degree cycle and thats hapening at 50 plus times a second http://performanceunlimited.com/illustrations/sparkplugs.html the plugs are normally done (the electrodes cut back)with a dremel tool cutting disk a few places to look for more info on plugs http://www.acdelco.com/html/pi_plugs_ident.htm http://members.uia.net/pkelley2/sparkplugreading.html http://www.atlanticjetsports.com/_techtalk/00000005.htm http://www.strappe.com/plugs.html http://www.babcox.com/editorial/cm/cm59910.htm http://www.ngksparkplugs.com/techinfo/spark_plugs/partnumberkey.pdf http://www.nightrider.com/biketech/spkplghnbook.htm http://www.tsrsoftware.com/sparkplug.htm http://www.gnttype.org/techarea/engine/plugs.html http://www.dansmc.com/sparkplugs1.htm http://www.ngksparkplugs.com/techinfo/spark_plugs/overviewp2.asp http://www.edelbrock.com/automotive/sparkplugs.html http://www.powerarc.com/sparkplug.htm http://www.carcraft.com/techarticles/64378/ http://www.wakularacing.com/TechnicalInfo.htm http://www.geocities.com/MotorCity/Flats/3877/spark.html this is how a sparkplug gets most of it's heat range.

Id first point out that the TPI ENGINES were and are saddled with both very restrictive heads and intakes, MOST TPI blocks were two bolt and generally if your thinking of a turbocharged engine thers not a single top quality part to be had amoung the factory provided components INCLUDING the BLOCK, now IM in no way suggesting you can,t reach your 500-550 rear wheel hp goal, IM just strongly suggesting starting with a basic TPI. engine is FAR from the optimum base to work from. next theres hp and tq increases to be found in the larger displacement and longer stroke of the 383 over the 350, and theres not much if any potential advantage in sellecting a 350 because you can,t use the cast pistons, lousy stock rods or crank if you expect it to live LONG TERM rather than a season or two. heres the stock 4 bolt block 1986-99 350ci 4-Bolt Main Bare Block P/N 10105123 P/N 10066034 http://www.sallee-chevrolet.com/frame.html?/Engine_Blocks/gm.html notice the MAX SUGGESTED POWER RATEING heres THE BEST FACTORY TPI heads Ive built DOZENS of the TPI engines and yes you can get 500 FLYWHEEL HP/TQ with the correct parts, BUT ITS BEATING A DEAD HORSE, COMPARED to what you could build for just alittle more money

YOU really need to read thru the whole post to understand the concepts, a 9:1 cpr engine in good condition,would normally produce compression test readings in the 140-150 psi range, 230 psi puts you about in the 12:1 plus cpr range heres more info (yeah it might be borring but without knowing what your doing your results will always be less than optimal http://www.chevytalk.org/fusionbb/showtopic.php?tid/92966/

I lived in the country, my favorits were a bear recurve bow and arrow and a 30/06 enfield rifle, yeah, I was WAY out in the country and I had a bow since I was about 9 a rifle at about 14 years old and I never go into TROUBLE with it AS I knew the concequences

if its not broken , just rusted in most cases a decent machineshop can clean, over bore and refresh the block with few problems, take it apart then drop it off at the local shop for inspection, in most cases they can tell very quickly

your FIRST need is to find out WHAT your actually running as to ENGINE parts, compression etc. MOST cams that sound excessively LOPEY at idle are designed to operate in the 3500-7500 rpm range and will be complete TOTAL DOGS in a 9:1 cpr engine COMP CAMS sells THUMPER cams that will give the lopey idle in your application but they are NOT designed for making POWER, just a LOPEY IDLE for CRUISE/SHOW CARS http://www.compcams.com/information/whatsnew/NewsDetails.asp?ListHistoryID=1172529887 230 psi IS not the reading youll get from a 9:1 cpr engine http://victorylibrary.com/mopar/cam-tech.htm you may want to go DUAL QUADS vs TRIPS as GOOD rodchester carbs are BOTH expensive and RESTRICTIVE http://store.summitracing.com/partdetail.asp?part=EDL%2D20254&autoview=sku

"Is that very big of a deal?" more of a NICE feature than a big deal, as its just not that difficult on any comon carb like a DEMON,HOLLEY or EDELBROCK, once your familiar with those carbs and the HOLLEY and DEMON carbs haveheavy duty synthetic gaskets available and your only talking about spilling about a cup total from both bowls combined. BUY TWO of these and REMEMBER to replace the jets you use http://store.summitracing.com/partdetail.asp?autofilter=1&part=HLY%2D36%2D181&N=700+115&autoview=sku or buy these http://store.summitracing.com/partdetail.asp?autofilter=1&part=PHP%2D15001&N=700+115&autoview=sku http://store.summitracing.com/partdetail.asp?autofilter=1&part=HLY%2D34%2D25&N=700+115&autoview=sku

280zwitha383 can you explain how you post that dyno chart from DD 2000 software??????

theres no reason a properly designed intake and carb combo with those carbs can,t work correctly but I see little to no advantage over either webers or a properly set up dual quad setup, yes short runners tend to raise the rpm band , but its not something that can,t be worked around to some extent, it seems to be a really expensive duplicate answer to a question that was answered long ago for less money http://www.rbracing-rsr.com/runnertorquecalc.html http://www.bgsoflex.com/intakeln.html http://victorylibrary.com/mopar/intake-tech-c.htm if you want to see what short runners and direct carb to plenum/runner intakes do to low rpm responce get an offy 360 intake, if you want to see what direct intake to venturie intakes can do, get the weber set up, BTW the webers are FAR MORE EFFECTIVE in the low and mid range IF LOOKS WERE THE MAIN OBJECT, because it LOOKS more impressive PLUS it produces better POWER

avoiding some of the modern oils designed for roller engines and catilitic equiped engines , and useing a high zinc content oil for flat tappet applications is a valid idea.

this is going NO PLACE for the same exact reason the orriginal ford inline carbs and webber 4x2 intakes were never very popular...NOT because they failed to work well, but due to total costs envolved and a lack of a wide range of matching intake manifolds at competative prices, you can get an intake, DUAL QUADS and linkage and air filters in a matched component set up for well UNDER 1/2 the total costs http://store.summitracing.com/partdetail.asp?part=SUM%2DCWND303&autoview=sku http://store.summitracing.com/partdetail.asp?part=EDL%2D20254&autoview=sku if your willing to pay big bucks... http://www.carburetion.com/Weber/wildv8.asp http://www.hilborninjection.com/product.asp?Id=52&CatId=37

CLEARANCE or VALVE TRAIN GEOMETRY ISSUES or lack of lube is far more likely to be an issue than rocker ratios, Ive only had ONE cam loose a lobe in the last 30 years and that was 30 years ago and MY fault as I didn,t carefully check the rocker to rocker stud clearance at the time on ALL the rockers (we all learn some things the hard way) use E.O.S. a good MOLY CAM LUBE, CHECK ALL CLEARANCES CAREFULLY, and use a high ZINC oil durring the break in procedure http://www.engineparts.com/Motorhead/techstuff/caminstall.html http://www.micapeak.com/info/oiled.html read these http://www.cranecams.com/?show=article&id=2 http://www.cranecams.com/?show=faq&id=1

http://www.crower.com/misc/cam_spec/cam_finder.php?part_num=00271&x=18&y=8 normally with a 4 speed, 10:1 cpr and 3.90 gears, Id suggest a solid lifter design as it will pull extra rpms, but the vortec heads pretty much restrict that advantage so to maximize what you do have, (great mid range flow and small ports) Id sellect this cam above, (hydrolic flat tappet) its going to lope noticably at idle, but have very good tq/power, especially if you install 1.6:1 ratio rockers as always call the manufacturer and discuss it, they may suggest a wider LCA but while it will make it more street friendly it will kill off a bit of power and tq, personally ID live with the roughter idle and get the more robust tq curve btw heres the cam IM running (EFI and auto trans, so its sensors and tunning limits requires the WIDER LCA) notice the similar durration...it makes killer tq and works well with a 250 hp shot of nitrous http://www.cranecams.com/index.php?show=browseParts&action=partSpec&partNumber=119661&lvl=2&prt=5 something to read thru, keep in mind you need self aligning rockers as you don,t have factory pushrod guide plates http://www.compcams.com/Community/Articles/Details.asp?ID=2132654598

whats your rear gear ratio, transmission,gearing, stall speed, intake type,compression ratio, are you useing headers and a low restriction exhaust,and are you willing to use a solid lifter flat tappet cam? BTW read thru ALL of this carefully http://www.rustpuppy.org/chp/Welcome.html http://www.compcams.com/information/Products/RockerArms/MagnumRoller.asp

DR HUNT gave you some good info, but ID also point out that 400 blocks REQUIRE the heads are drilled for extra steam holes in the heads (your local machine shop can do this) and ID also point out that the COMPRESSION RATIO, cam sellected and rear gearing must match to get the most from the combo! your 400s larger bore helps breathing potential and larger bore surface area helps tq. the added displacement helps also, over a 383. now I don,t know the intended use but if your intent is to maximize the power curve (mostly race vs street use)youll need at least a 10:1-10.5:1 cpr and a cam in the 230-245 at .050 intake durration range and a drive train set up to operate in the 3500rpm-6400rpm band (usually a manual trans or auto with a 3500 rpm stall converter and 3.73-4.11 rear gear just some basic ideas http://airflowresearch.com/articles/article074/A-P1.htm http://airflowresearch.com/articles/article093/A-P1.htm

the first thing ID do is REPLACE the OFFY 360 intake with a EDELBROCK AIR GAP RPM INTAKE, youll easily notice the differance in MUCH improved low and mid rpm torque with little to no loss in high rpm power. offy makes some great intakes but the 360 series was not amoung them

first ID point out that 409 leaves a film, you degrease with acetone or toluene on a clean rag. next it sounds like the wrong seals were used, youll need to get a one piece synthetic oil pan gasket and the correct rear seal installed correctly and lightly oiled (read instructions) EDELBROCK cams are old tech, but that didn,t cause the failure, CLEARANCE or VALVE TRAIN GEOMETRY ISSUES or lack of lube is far more likely read these http://www.cranecams.com/?show=article&id=2 http://www.cranecams.com/?show=faq&id=1 heres a check list a few things that should always be checked on an engine build heads are the pushrods perfectly strait? do the pushrods flow oil? rocker studs/guides torqued correctly? do the head bolts have washers under the bolt heads? are they the correct length for the cylinder heads in use? have the heads been pocket ported? combustion chambers unshrouded? intake ports gasket matched" are the valve guides cut to the correct length? what are the valve to valve guide clearances? are the heads pocket ported? is the retainer to valve guide clearance correct? are the valve guide oil seals installed? is there valve spring seats installed? inner damper springs installed? spring bind height checked? (to exceed max valve lift by .050 min.) ON EVERY SPRING????? oil return holes cleaned of casting flash? were steam holes in heads necessary? were the spark plug threads of a installed spark plug extending into the combustion chamber? rocker slot to rocker stud clearances ? retainer to valve guide clearances? spring bind height checked for the correct spring pressure? valve lash/preload ? are the valve springs the correct tension,height?dia. keeper the correct angle? style? size? valve seats the correct angles? valves back cut? valves the correct length, stems the correct diam. strait? are the seat angles correct? rockers the correct ratio? were the valve to valve guide clearances checked (CAREFULLY)? were the heads milled? did the head gasket overlap the bore? what are your valve train clearances? is the rocker arm geometry correct! chambers CC,ed did you check the piston to valve clearances? port work..(some steps optional) (1) open throat to 85%-90% of valve size (2)cut a 4 angle seat with 45 degree angle .065-.075 wide where the valve seats and about .100 at 60 degrees below and a .030 wide 30 degree cut above and a 20 degree cut above that rolled and blended into the combustion chamber (3)blend the spark plug boss slightly and lay back the combustion chamber walls near the valves (4)narrow but dont shorten the valve guide (5) open and straiten and blend the upper two port corner edges along the port roof (6) gasket match to/with intake and raise the port roof slightly (7) back cut valves at 30 degrees (8) polish valve face and round outer edges slightly (9)polish combustion chamber surface and blend edges slightly (10) remove and smooth away all casting flash , keep the floor of the port slightly rough but the roof and walls smoothed but not polished. (11) use a head gasket to see the max you can open the combustion chamber walls (12) blend but don,t grind away the short side radias block is the oil pump pick-up mounted 3/8"-1/2" from the oil pan floor/ is the windage screen mounted about 1/8" from the rotateing assembly/ is the pick-up brazed to the pump body? has the oil pump relief piston in the oil pump been checked for free ,easy movement? clearance? spring tension? is the oil pump pick-up tube inserted too far into the oil pump body,(binding the gears) has the block been clearanced for the rotating assembly? has the block been aline honed? is the crank strait? are the damper install keyway and threads ok? counter weights clearanced? MAGNAFLUXED? OIL PASSAGES CLEANED? GALLERY PLUGS INSTALLED CORRECTLY? has the cam to rod bolt clearance been checked? piston to valve clearances checked? piston to bore clearances? TRUST BEARING CLEARANCE? what were the piston ring to slot clearances? RING GAPS? were the rings all checked individually for end gap in the cylinders they were used/installed in? were the rings checked to make sure the correct side faced up, and the correct ring was in each groove? what were the back clearance on the rings? were the oil ring expanders carefully fitted for correct drag? were the oil ring scraper ring rails checked for end gap? total cam lift and remaining clearanceS? WAS THE CAM DEGREED IN? main bearing clearances? what is the main bearing run-out clearance piston to head clearance? (QUENCH?) head gasket to coolent holes checked? magnets installed? rod bolt to block clearances? what tq reading is necessay to spin the crank with no rods attached? are the rod bolts and main caps torqued correctly? (rod bolts checked with a bolt stretch gauge?) did you check the block for a strait main cap alignment? what size journals and what were the bearings edge to filet clearance?? are the journals checked for finish and run-out/tapper? did you use moly lube to assemble? correct bearing crush? did you pre-lube before start-up? did the distributor gear fit the cam gear precisely? was the distributor oil flow mod done? was the correct style distributor gear used? did you check the piston to piston pin bores for fit and clearance? did the piston pins to snap ring clearance seem overly tight? if they are pressed pins were they correctly matched and checked for free movement in the pistons? was the engine ballanced? cam button installed?, and lock plate installed? were the rods resized? checked for parrallel bores/were the rods strait? piston valve clearance notchs correctly located on the pistons? edges smoothed? were the rods checked for length? is there a few thousands clearance on the oil pump drive shaft AFTER the distributors bolted down? did you install a steel collar on the oil pump drive shaft? was the rod to piston pin side clearance checked? (at 4 places seperated bye 90 degree spots) does the oil pump drive shaft mid section clear the block with the pump installed? whats the starter to flywheel gear clearance? is the pilot bearing to trans imput shaft clearance ok? is the front motor mount bolt to fuel pump pushrod clearance ok? did the fuel pump pushrod move easily/ are you possitive the pistons were installed with the correct valve relief in the correct location?(eiieeiie) were the pistons installed with the correct side facing forward/ what torque values were used on all fasteners/ were they the correct length and type bolts? were the bores honed with a torque plate in place? was the cylinder finish correct for the type rings used? was the oil pump itself checked for free spin and clearance AFTER THE PICK-UP WAS INSTALLED? was the cam drive checked for free rotation and drag/ were the oil passage plugs drilled for extra oil flow? were the lifter bores checked? cam to timing cover clearance? cam journal to cam bearing clearances? was the cam journal run-out checked? was the cam degreed in or just lined up useing factiory index marks? has the rod and windage screen to oilpan clearnce been checked? does the dipstick & tube clear the windage screen? was the cam lobes/LSA/LIFT CHECKED? is the deck square/level? whats the cross hatch hone angle? what grit hone was used? is it correct for the rings used? are all the threads clean/clear? brass freeze plugs installed? block painted? a few things to check are the connecting rods installed with the beveled edge facing out on each pair with the bearing installed with the bevel facing out on both the lower and upper rod bearings also? are you using beveled bearing shells that match the cranks throw bevels? what are the bearing clearances? (are they the same checking at 90.120.160 degrees from the first measurement?} what are the connecting rod side clearances? is the crank strait? has it been turned undersize? if so...on ALL the rods? on ALL the mains? or on ALL the BEARINGS JOURNALS OR ONLY SOME? whats the TRUST BEARING CLEARANCE? is the piston side clearance correct? are the pistons installed in the correct cylinders? (intake and exhaust notches correctly located to match the cylinder head) are you POSSITIVE each main cap is in the correct location and FACING THE CORRECT DIRRECTION? did you use MOLY assembly lube? did you check EACH INDIVIDUAL RING ON EACH PISTON for ring gap clearance,AND that the rings fit the piston ring slots correctly? are any rings installed in the wrong ring slots (2nd ring in top slot ETC,)or upside down do the rings have back clearance? were the cylinders CORRECTLY HONED? is the cam drive binding? does the crank contact the windage screen? does the dipstick tube or dip stick touch the crank at any point? is the oil pump /cam gear binding? did you check that the oil pump mounting bolt does NOT contact the back surface of the rear main BEARING under the main cap? is the block warped, checked carefully?,was it line honed? are the piston pins centered? do the pistons rotate thru an arc with little resistance? are there any lock pins, spirolocs, tru-arcs contacting the cylinder walls? are you sure the bearing shells are installed correctly and the locating tabs are in the correct slots? are they the correct bearings for the application? or did you just assume the part guy knew what he was doing? did you MEASURE or GUESS, did you at least use Plastigauge and a torqure wrench? did you check EACH AND EVERY journal for tapper and roundness did you get the rotateing assembly ballanced??? be sure you check clearances carefully, a mistake can and will damage the engine, DON,T GUESS most people tend to tell me Im wrong about that untill they try it both ways yeah the differance is usually minor but five to 10 thousands differance is not rare if the parts are clean and dry versus sprayed with an oil mist first check to make sure that you are measureing correctly, many times the valve actual has more clearance in the flycut clearance notches,or only the very edge of the valves head and the edge of the notch are close and very minor cutting with a tool fitted in a valve guide will clear the problem and the valve has more clearance than measurements taken from the pistons upper surfaces, and that the head gasket thickness and valve train geometry are correct, check if changing the cam retard/advance or installed possition can be changed to increase the clearance to 0.100 minimum on both the intake and exhaust valves (MOST LIKELY TO WORK WITH THE LEAST PROBLEMS) add a thicker head gasket? ( BUT THAT TENDS TO RUIN QUENCH AND DOES NOT TEND TO BE A GREAT CHOICE ON MOST ENGINES)

http://www.warwickdragway.com/Calculators.html 7.7 1/8 equals aproximately 12.01 1/4 get decent traction and your well into the 11s, once the traction issues handled ID suspect some tunning issues need looking into, but your getting there!! what did the engine feel like in comparison to the old 350 it replaced

"shows as $79.99 for me.... is this an unadvertised special?" its advertized in the flyier theysend out about once a month sale ends on the 9TH flier 137-1B pg 18 " think mine are the 6 ton, work very well." THERES NO COMPARISON! the 12 ton are MUCH larger, steadier , and stronger

Well????

"Last time you advised how to drive it you said shift at 7300!!" NO! just trying to allow you maximize the TQ curve rather than HP in the POWER curve untill you get the traction issues resolved, and SLICKS

just learn to ease into the throttle as you launch you DON,T want to just floor it untill your moving well.. and youll get the hang of it quickly..BTW adjust the tires air pressure up/down UNTILL you get a full width even black patch as you launch edges darker too low center darker too high BTW shift at no higher than 6400rpm

I think its working now

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=34924 12 ton jack stands #34924 normally $80 for two, now on sale for $55 for two, SO GET FOUR NOW! now theres not much at harbor freight thats well worth the price but these are low tech and well worth the cost, Ive had 6 in the shop for years, they are just the correct height at the lowest setting to work under your car and FAR AWAY MUCH LARGER AND STEADIER, more heavily built, than the comon jack stands most guys use

2126 is CORRECT but GALLING also causes failures "GALLING The damaging of one or both metallic surfaces by removal of particles from localized areas due to seizure curing sliding friction or impact welding under pressure of two similar metals BTW COPPER/and BRONZE are frequently bad about this http://www.safetyline.wa.gov.au/page...chhazd0001.htm http://danrrec.ucdavis.edu/ehs/safet...15_grinder.pdf http://www.magion.com/Applications/Galling/galling.html