ok .. i got a 91 camaro z28 convertible with the 305 tpi, 5 speed manual, and stock rear gears 3.08 posi ..

i just rebuilt the motor and put on:

summit racing vortec heads ( 1.94, 1.5 ... 170cc, 67cc .. .520 max lift)
edelbrock vortec tpi hi flow intake manifold
hooker 2055 headers w/ 3" y pipe
comp 501 cam (212, 218 .. 264, 268 .. .480, .490 lift .. hyd. roller)
aluminum flat top pistons (+5.00 cc)
thinnest metal head gasket summit has
(compression is around stock now b/c of bigger 67cc chamber heads)
double roller timing chain
all new sensors
new distributor / ignition module
new coil
taylor 8mm wires (and 10.5 mm coil wire)
accell shorty u groove spark plugs
flowmaster muffler (stock pipes and took cat off)
bbk adjustable fuel regulator
new fuel filter
k&n air filters


now its running on the stock tune just fine and feels REALLY strong at 8* timing and 46psi fuel but before i tune it i was going to wait and put these on it:

twin 58mm throttle body
22# injectors (stockers are almost shot even though they ohm just fine)
3" cat back system / hi flow cat (for emmisions purposes)
slp high flow runners (or are edelbrock's better ?? )
air foil (do they work ??)
more powerful coil
1.52 roller rockers


if i put these on my motor and then get it dyno tuned (or tune it myself).. how much more power should i be looking at than right now w/ the stock tune and not having these last few upgrades ..

i think my stock runners are holding me back right now .. and my stock non mandrel bent exhuast is choking it a little ..

thanks ..

adrian

 

the throttle body is a waste on any 305. and even most 350's. not worth it, if anything it will affect performance negatively. idle issues. injectors- im sure you need the extra 3pds with that cam and those heads. as for the runners im in the same boat as you, im not sure if i would benefit from opening up my whole intake. so id like to see the response on that ?. i would like to port the plenum and get some slp's too. my mods are in sig and im adding a procharger.

 

yea .. i did a little research and talking to other guys with camaros .. and found out the throttle body doesnt help like it does on a mustang ...

so that is out of the plan .. and also .. im not going to upgrade injectors b/c mine are plenty for now ..

i might get bigger ones when my 19# er's go out .. but thats a not for a while

but im sure that the runners / and a 3" mandrel bent exhuast will help alot .. and a good tune ..

so thats the plan for me right now .. ive had a couple people say i should pick up around 40 to 50 hp /tq across the whole powerband with those upgrades and a good tune ..

i believe that b/c sometimes right now i get alot of power and others times it doesnt seen to pull as hard .. but im sure thats the computer trying to figure out the fuel mixture ..

but i will say my car cruises REALLY nice .. goin 60 at 1550 rpm is nice .. hoping its good on gas too .. ill find out tommorow ..

also .. what octane should i be running .. i got a 9.4:1 compression ration ..
right now im running 8* timing / 46 psi .. but im only running 87 octane (cheap crap) .. i filled it up today and put half a bottle of octane booster .. so ill see how that goes ..

any suggestions .. i thought that if i run higher octane i dont have to advance the ignition as much .. or is it the other way ..

thanks ..

 

I agree, the TB isn't worth it. You need a hefty 350 or bigger. As for the airfoil, well, every horse counts. -but don't really expect to feel anything. The catback exhaust is a MUST!!!!!! DO THIS NOW! The stock exhaust is terrible.

My experienced, yet unproffesional opinion is that runners will probably help on the dyno, but you probably won't feel much. My bet is that your hopped up 305 is just about flowing at capacity, but not necessarily being restricted too much. I don't think they'd hurt though, and they ARE cool......so I'd probably get 'em.

 

the biggest thing about the semi siamesed SLP runners is shifting the power band upward. you may not make much PEAK power over stock runner setup, but you'll move your peak power up a couple hundred rpms which DOES make a difference at the track.
Say stock TPI runners peak at 4800 with that motor, making a theoretical 225whp. Now lets say you add SLP runners and peak power is 230whp but now at 5400rpms... that is only a gain of 5hp but moved peak much higher. This will make for more area under the curve and will give the motor a chance to stay within a better powerband when going down the track. You can now add more gear to take advantage of your car's power. Your ETs will improve.

 

allright .. im probably going to do the exhuast first then ..

plus .. a guy at summit wants to buy my stock 305 heads, tpi intake, roller cam, exhaust, etc ..

basically most of the stuff i replaced ..

anyone know a fair price on this stuff .. i was just going to throw it in the corner with all my other car parts (past cars)

whatever i gain from that will be going torward a 3" exhaust ..

 

cool, sell all that stuff. and buy the adjustable borla.. you will luv it!

 

the borla sound good? .. better than a flowmaster ...

right now my flowmaster sound nice at idle .. but at speeds, inside the car it has a deep tone to it ..

i looked at the pictures of the borla .. why does it look different than a normal setup ..

EDIT: actually ... $900 is a little steep for a cat back system .. im looking for something around $300 ..

which one is best ..

flowmaster
ultra flow ss
hooker (im leaning torwards this or a flowmaster)
pacesetter
dynomax

those are all in the $200 - $350 range ..

 

just read the stickies on the exhaust page. and do a search too for borla.
yes i too think that rustmaster sounds good. but it dosent flow that well, and its really heavy, and gets rusty. i prefer borla, gmmg or hooker. all flow great and sound awesome. the hooker is a bit on the quiet side. but it flows great and is fairly inexpensive.
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can one of you guys give me youre opinion on what i wrote in post #2.

 

On your build....I DO agree w/everyone else...think of your engine via the air/fuel delivery. As we know a 305 has smaller TB and injectors. Your are building an engine with bigger internal components that sound like all together it can handle a good amount of power.....the only way you can possibly make power is with proper amounts of air/fuel and MOST IMPORTANTLY(i speak from expierence..thanks Chris) a proper tune (chasis dyno tune) to balance out the air /fuel, sensors, ect...
You need a 58mm TB, BBK makes a great one for our TPI's. The injectors..I'd match a 350 stock lbs. per hr (I think its 20-22?) another IMPORTANT thing to concider is your fuel pump...its game over if it can't deliver the fuel through the lines fast enough....its not really the injectors that you have to worry about.

NOW-I HATE to be the black cloud..adrians91z28...if you wan't to make GOOD power, port the plenum, get siamese runners, and a better intake(hi-flow) my engine alone(not to the rear wheels) is about a 400hp motor...to the rear wheels i'm at 300hp-330tq. All my dyno runs show my power curves to drop off at about 4500-5000rpm's ONLY BECAUSE OF MY INTAKE SET UP....100% honesty..I have found that the TPI SET-UP SUCKS!!!!! . The Super Rams, are better but its the air delivery design that kills us..

SORRY TO TYPE SO MUCH!!! But the final though w/the TPI setup. Air flows in one straight direction unsless diverted otherwise...think about this....Air rushes through the throttle body and slamms into the back of our plemun only supplying the back half of the engine properly...now this amount will not KILL any engine but when were trying to SUCK every little HP number...just take this into concideration.....

 

well i think any 305 with bolt ons can benefit alittle with intake mods, but especially if you got cam and heads. Stock L98 will peak by 4500. 305 should beable to use TPI to 4800 possibly 5000 rpms. Still, the long runner design of TPI is optimal to boost 4000-4600 rpm performance. I'd open up the intake for more flow and siamese it to peak your power band up in the higher rpm ranges. Its worth it to move your powerband up from 4500 to over 5000 rpms.


And i'm still thinking a throttle body is a waste of money on your setup. sure you have heads/cam but its not a wild setup. 48mm tb is enough to feed some mild 350's so i wouldnt hurry up and spend money on that. That be the last thing to try for power after the tune is done, and the exhaust is done.

stock 19 lb injectors will feed that car with the fuel pressure turned up and more tuning in the bin. you can add alot of fuel in the chip with those stock injectors. only replace them if they are very old and you think they will be goin out sometime soon, which is hard to tell if they ohm out correctly at warm temperature.

 

ok .. ive got about 120 miles on the car (111 on the new dash, and 9 or so before it)

found out in rush hour / morning traffic im getting 20 mpg this morning (19.75 to be exact)

now to me thats damn good .. but im sure itll do more with a tune

i allready have the edelbrock hi flow intake manifold for my vortec heads, but i am going to get a set of siamesed slp runners and port the plenum .. then put on a hooker exhaust (still looking at videos on youtube)

and after all that .. i can tell i definitely could use a good tune ..


does anyone think i should put in a hypertech chip for now b/c i got a lower thermostat and fan switch .. and i think it might be messing with the computer a little .. there only like $110 or so ..b/c i dont plan on getting a tune for about a month or so ..

im about to change the oil for the first time .. when is it safe to stick something like royal purple in it .. i thought i saw something that said use it after 3000 miles ..

 

The lower temp thermostat will definitely confuse the computer, but, it will get over it. If you are getting almost 20mpg now, save the money, and put it toward the tune.

 

get that thing on a dyno a.s.a.p im very curious on the numbers?

 

yea .. i want to know just as much as every one else ..

but i changed the oil a minute ago .. and that 3" hooker y pipe hooked up to the stock 2 1/4" makes me depressed .. hahaha .. i REALLY want to get the exhaust and runners real soon ..

then im gonna call around the atlanta area and see where i can get a good dyno tune for a decent price ..

what should i expect to pay for someone to put my camaro on a dyno and tune the computer to max performance / fuel economy

also .. i only have about 125 miles on the motor .. im not going to thrash on it for a little while .. want to get atleast to 3000 miles before i get to redline .. most ive been so far is 4000 once or twice (well once on accident today, missed the shift to second b/c my backend slid out during a turn .. hahaha )

im sitting at 8* timing right now .. and 46 psi .. but i checked the plugs a second ago that have about 100 miles on those settings .. and they look a little white to me .. like there barely tan but have some white spots on them

is it running lean? b/c sometimes it smells a little rich (before it warms up) .. what should i turn the pressure up to on the 19# injectors .. and how far should i go on the timing .. or leave it the same ..

and does the base timing depend on the octane gas b/c right now im using 87 octane with half a bottle of "orielly auto parts" brand name octane booster ..

 

if it were me i'd probably bump the fp another 2 or 3 lbs. I'm sure 2k rpms up your running lean.

2k down your probably running overly rich. In other words don't go over 2k and leave it alone or bump it up just for the safety factor. As for timing 8* is close enuff i'd leave it alone until it's tuned.

a dyno tune usually runs 300-400 but, they normally only tune wot so drivability elsewhere will be somewhat lacking..... then again maybe you'll get lucky and they'll have a slow day and do a better job for a good price.

as for oil i'd do the initial with a good brake in oil like rotella then after i swap straight over to full synthetic. Btw i'd stick to mobil 1, on most oil boards its rated a good bit higher than royal purple and is a good bit cheaper.

Pure one oil filters from advanced are also my favorite they look like the same exact innards as a k&n filter but, cost a little less than half the dough.

either way any oil will do you though honestly...

 

when im driving it to college and stuff it allways is under 2000rpm

so if i bumped the fp up a couple pounds .. would the computer sense this and shorten the fuel under 2000 rpm .. or would i just be wasting gas b/c its almost doing 20 mpg right now ..

as for the power .. it starts pulling around 2000 rpm .. but really starts haulin around 3800 (peak power according to the desktop dyno) ..

sometimes itll respond straight away and throw you back in the seat .. and other times it will "stumble" a little then act like its got a little less power .. probably just the stock tune doing it ..

300 - 400 is what i was thinking .. but im gonna call around a few shops and talk to them .. if they dont do the whole range of stuff then im just going to do it myself and pay for a dyno run seperate (like $50 when the dynomax tour comes back to summit)

anyone know a place near the atlanta area in georgia that does tuning on our camaro's ..

thanks ..

 

to be honest with you.... if you put 120 miles on the car and its running ok, hammer down on it a few times to help further set the rings. Change the oil again after the few WOT runs and then its broke in.

dyno tunes can be around 100-150 an hour for dyno time and then another 100-200 for the actually tunning which i think is a rip off. Tuning wot isnt that hard with these cars for most combinations and should only charge 50-100 plus dyno time

 

aight .. sounds like an idea ..

i drained the old filter today in my hand and found very small metal pieces .. im assuming this is the "break in" excess metal .. nothing big at all .. VERY tiny bits of metal ..

im gonna turn the fuel up to 48 and check the plugs again .. i drive about 70 miles a day now .. and if there still light tan.. ill turn it up to 50 ..

then around 500 miles .. probably next week .. hahah .. ill change the oil again .. and put on a slightly better oil filter / name brand oil ... i got the cheepo orielly 10w-30 .. and the cheapest filter they sell for break in ..

 

yep from the brake in. thats why i'd change the oil, which you did, and then hammer on it to further set everything. like 3/4 throttle to near redline, then maybe a full throttle blast to near redline.... then change oil and filter...inspect for more metal and if there is still alot then run it around for a few more hundred miles, and change oil again. it should be fine by the second oil change after the wot blasts

 

White spots on the electrode of the spark plugs is a sign of detonation. You need to run 93 rather than 87 I would say... IIRC - it calls for premuim fuel with an octane of 91 or higher in the owners manual.

 

yea .. i took it to college today .. and took a plug out and showed the automotive teacher .. and he said dont run any "junk gas" .. put in 93 octane ... but he thinks the fuel mixture is fine .. the plugs look like there cleaning off (the black) and there a VERY light tan in some areas .. in others there clean ..


so i put 5 gallons of 93 in the tank full of 87 (with octane booster) .. found out its doin 15.5 mpg when im stompin on it at every light .. so im gonna ease off a bit now and wait till i get 93 octane bled threw the system ..

 

just until you do run some 93 octane through. dont rev that thing up to high, so drive it like an old lady for now. also that youre build is still nearly new change youre oil a few times ( no synthetic) not for a while anyway. and remeber not all 93 is the same.. junk gas isnt just low octane. all gas companies add different additives. stick with exon, shell, mobile and bp.. hess is horible dont run that or any other junk gas.. i hope this makes sence.

 

true, i thought your gas wasnt optimal. flush the system with 93 for alittle and then get on it. i think your fuel is about right once you step up 2psi or so fuel pressure.

 

ok .. filled it up with some 93 octane gas .. (5 gallons)

and drove 15 miles .. then a "ticking" started appearing on acceleration .. very quiet at idle .. but still noticible with the hood up ..

any ideas what might cause this ..

also my oil pressure is reading 99 (max on digital gauge) untill it gets warmed up / runs for a little bit .. and even then it still reads high

but that might be a bad ground causing that ..

neways ... it starts "ticking" louder as i accelerate and sometimes it will stop for a second or two .. then keep ticking ..

could this be detonation since i put the bp 93 octane in .. sounds to me like an exhuast leak in the rear passenger side ..

i got hooker 2055 headers .. are their gaskets known to leak ..

also .. it kinda stumbles when i start out in 1st untill i reach about 1200 rpm

could it be my injectors .. they ohm'd at 16.3 .. but when hook up the fuel pressure gauge .. the pressure slowly drops about 1 psi / minute ..

im going out there to check the plugs / injectors and stuff when it cools down .. and hopefully it isnt something major like a lifter or something ..

 

Could be a number of things. Injectors are known to tick. Headers where they meet the Y pipe are known to leak and make a ticking noise. Does it only do it if you get on it a bit? My 305s got edlebrock headers and they tick cause i have an exhaust leak where the passenger header meets the Y pipe.

 

ok i got it sorted ..

my rear two bolts on the passenger side header were loose ..

i got up under the car and could move the gasket around about 1/16 of an inch


.. but after i got done .. (havent started it yet b/c i have some epoxy on some pinholes one some welding) ..

i checked the codes and got 12, 42, 43 .. i havent noticed a check engine light whilst driving ..

but could it been b/c of the exhuast leak .. (???)

its running allright .. its at 8* timing and 46psi .. but i noticed in the last few miles it was stumbling when i started moving in first .. wouldnt respond too well in 1st gear ..

should i unhook the battery and see if they show up again tommorow?

 

remember to check those bolts and others often, my arp bolts and hooker 2055's never stayed tight.

you could try resetting the ecm to see what happens with the codes.

 

yea .. i was thinking of resetting the ecm in the morning ... then check it when i get to college (about 30 miles) and see if they come back up ..

dont remember seing the "check engine" light one all day today .. so it might of been that exhuast leak that happened 10 miles ago ..

 

also my oil pressure is reading 99 (max on digital gauge) untill it gets warmed up / runs for a little bit .. and even then it still reads high

that sounds pretty insanely high. I'd be kinda worried about that especially since it's newly rebuilt. I'd double check and make sure your sending unit works well and that your wiring to it is good. If so check your grounds as you said.

also .. it kinda stumbles when i start out in 1st untill i reach about 1200 rpm

that i'm sure is mostly just because, the tune is hugely off. Drivability is going to be pretty lacking i'm sure until you can get it truly prom tuned. For now just make sure you don't go crazy with timing and keep her overly rich if you're going to stomp on it.

i'm sure you noticed my thread, with a maf computered car and just lots of bolt ons my drivability has still somewhat mildly suffered.

could it be my injectors .. they ohm'd at 16.3 .. but when i hook up the fuel pressure gauge .. the pressure slowly drops about 1 psi / minute ..

naaaa thats normal although if i were you i'd upgrade to 21# injectors. when you're ready to have her dyno tuned but, i'm sure you were planning that anyways.

use the old broom handle trick all over her, see if you hear any ticking.

yah definetly reset the ecm btw. Check and see if they come back.