by the beginning of august, I have to have my car finished and I have to race my brother and his stock z28. My car will have a rebuilt 350 with a cam with matched springs, intake, self ported stock heads, headers, cut outs, a rebuilt tranny, and a posi 3.23 rear end. His car is bone stock cept for a chrome k&n intake thing. With his car, he runs 14.0 in the 1/4. Now, Im trying to figure out how my car will fare against his? Can I win with this. What would I have to do to get into the 13's??? Any responses will be a great help.

how bigs the cam?

hmmm, lemme check

Cam Style: Hydraulic flat tappet
Basic Operating RPM Range: 1,500-5,500 RPM
Intake Duration 050 inch Lift: 218
Exhaust Duration 050 inch Lift: 218
Duration at 050 inch Lift: 218 int./218 exh.
Advertised Intake Duration: 268
Advertised Exhaust Duration: 268
Advertised Duration: 268 int./268 exh.
Intake Valve Lift with Factory Rocker Arm Ratio: 0.454
Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.454
Valve Lift with Factory Rocker Arm Ratio: 0.454 int./0.454 exh. lift
Lobe Separation (degrees): 110
straight outa summit

I think you'll take him if he's only running 14.0

Anyone else got any input, or cheap ways that I can shave some time off, any ideas would be awesome.

I think it will be close.Once you have your combo dialed in I think you will nudge him out.

What heads are you using? I assume L98's. If so, you ought to go with some more lift, seriously. I ran .442/.465 on my little 305 and I know your 350 with superior heads and build can take alot more lift and still be streetable. Look into hitting .500 lift.

As for what you'll run, did you keep the TPI? If you went carb, what carb and intake? In any case, you should have no problem taking the LT1 down...how much problem i do not know.

if its a fresh rebuild then it shouldnt take much to reach into the 13's. i am there with only exhaust and 2800stall and some suspension work on street tires and 2.77 gears. you can easily get there with the stock L98 cam, but since yours is abit bigger, it should make 20-30hp more over that stock L98 cam.

Sorry for leaving this par out. I have a stock quadrajet, with the weiand egr intake. Im pretty sure these are not L98 heads, but Im not sure. Im swapping out my 305 for the s50, which is out of like a 78 or so Chevy Caprice. I believe the heads are from there too. Are these worse than the L98???

Thanks for all the replies by the way

I took out my friend with a ZZ4 Cam, full american thunder exhaust, with headers and a chip. And I only had a catback and free mods..

Had him by a car or so at 110.

my car was messed up though buddy (cam lobe in the oilpan)

The heads off the Caprice are garbage. They are probably the "993" casting, which are absolutely junk. You can post a casting number if you like...but even as much as L98 heads lack, they are still better than that other crap.

bs, dunno when you wiped that lobe.

And dear ***, don't use those caprice heads. Just port out your L98s, that will serve you nicely unless you want to go aftermarket

What he said.....Id just clean up those L98's and put those on. That will be a decent flowing heads for a mild street application. I had a pair of those "993" heads a few years back, and they left a lot to be desired. If you have access to some L98's, by all means use them. As far as everything else....sounds like you should have no problem with 13's.

are L98s the ones that came on my 305??? Whats the difference between the two... Again, thanks for the replies

hmm rough idle, takes awhile for a lobe to get inside the oil pump

The stock heads for your 305 are more than likely the "416" casting heads. Those heads have a 58cc chamber, and 1.84" intake valves. Ive heard from others that they have decent flow characteristics, but on a 350 the small chambers would put the compression too high for street use. Also, the smaller valves wouldnt really help performance. They can be worked though. Ask "SITTING BULL". He ported a set of those himself and i think he had good results. Hes well into the 13's with a 305. It would be worth it though to hold out for a set of the L98's. Or at least something better than the "993" heads....and go from there. Theres a lot of heads out there that will give you a good baseline, and good results from porting.

could have happened within 5 seconds, could have taken a few days.

The stock casting heads on your 305 are probably 416s, which when ported and cut will flow better than stock L98 heads, and boost compression due to the smaller chamber. L98 heads are the heads that (surprise) came on the L98 engine - the 3rd gen 350.

They flow decently when ported and cut.

i know when it happened buddy its my car im the one drivin it. i know a lot more than u about it.

hey L69,

Im using 081 heads on my 350 roller block.
and Im alil concerned for the street use of the car.

I went with the 081s cause they were free, and in very
good condition, they have been restored to new.

I will have trouble running pump gas?
or any other issues I might run into?

I didnt think Id run into any problems ..

Does the 350 have the stock pistons in it for an 87+ roller motor? What is the motor out of? If its out of a thirdgen, the compresion will probably be around 10:1 with head gaskets that have a stock compressed thickness, hwich I believe is around .039" (someone correct me if Im wrong). If you have a knock sensor youll be fine on the street....just run good gas for race days.

I thought the factory used a .018" shim head gasket. Most rebuild gaskets are between .039" and .044" so you usually lose compression if you don't have the heads milled or block decked. I don't know for sure though, its something I've heard.

I just checked this morning. My L69 and my ZZ4 350 both have a composite head gasket with a compressed thickness of .039". And they are both factory GM gaskets.

I'll race you and beat you again then, if you manage to not blow up your car again.

[Cocky LS1 guy]..and I'll beat you both[/Cocky LS1 guy]



Anyway, back to the topic at hand, you should beat him.

No one likes a meany

I'm only playing

thanks for the reply,

I put the stock pistons back in when I rebuilt the bottom
end with a friend.

89 L98, in good shape when I disassembled it.
Im running all sensors and stock wiring warness in my
my 89 T/A.

I sold the L98 heads, and got
some 081 casting 305 heads as I stated above,

did moderate porting to the heads, cam swap,
1.6 roller rockers.

left the TPI alone w/ stock injectors, ill be upgrading if
I pass emissions!! .. I hate AZ smog laws

Oh I know. I just hate how much power you guys make

Can't complain, lid, ported TB and a catback and I'm trapping at 108 though an A4.

Can't wait until the headers go on

Yeah, tell me about it. Im stuck with them too.

we'll see if u don't blow ur 170k stock lt1 that supposedly makes "310hp"

Yeah well I'll smack you with a stick!

And to finally shut 3.492rs up..

AHEM!!!

Most stock healthy LT1s dyno right around 255-260 HP, REGARDLESS OF YEAR OR TRIM MODEL. (refer to THIS thread for more info.)

NOW using very standard drivetrain approximation (17% driveline loss for an auto, which is what I've seen as the standard - that's about right, eh shifty?) we can see that 260 RWHP equals out to 304 FWHP. I've seen autos taking as much as 20% in some equations, which would raise our flywheel horsepower to 312.

RWHP * 1.17% = Automatic flywheel horsepower. Or in this case: 260 * 1.17 = 304. And that's conservative because the conversion factor is usually more than 17%.

NOW let us examine a conversion formula using quarter mile time. Also in that thread you can see most stock LT1s average between 13.9 and 14.0 (One freak ran a 13.64).

Using a conservative (below average) track time (some people may consider this average, I consider it slightly below) of 14.1@97 MPH I come out with the following answers to RWHP for a 3750 lbs car (which is what mine weighs at raceweight):

Trap Speed Method: approx. 267 HP
ET Method: approx. 264 HP

According to the above driveline loss formula:

Trap Speed Method: approx. 312 FWHP
ET Method: approx. 308 FWHP.

Yeah, my LT1 REALLY HAS 275 FWHP. Rofl. The only things different between my motor and the "corvette motor" (you'd believe THOSE hp ratings right???) is that the vette motor supposedly had slightly better exhaust. But the vettes were way lighter than the fbods. The vette LT1 was rated at 300 in 1992, don't remember the other years ratings.

And that is why I estimate my motor at somewhere in the 300-310 HP range, stock.

sorry for the hijack.

And it has 155k, and has always been fully maintained.

i still don't believe that bs. didn't u say ur gonna get a dyno done like 3 weeks ago. ur numbers and math skill means **** to me go get a dyno and post some realworld numbers. dumbass

All the hostility...all because you got smoked

true dat. I don't claim that my engine has the same HP, I just say it most likely does. And the fact that it's modded makes it even more likely.

But i do need a dyno, im trying to arrange something right now for bay area guys, like a cheapie dyno day.

prove it

not really one car length at 110 u call that smoked???

Well its very true and there are thousands of other LT1's just like his with the same numbers. His times are very impressive for 3700 lb A4 car. Any stock LT1 makes 300 at the crank. This isn't a secret to anyone.

Lets not get to hostile guys.

Meh, you lost. Stop making excuses...you lost.

I wiped my cam, my muffler bearings were bad, my blinker fluid wasn't filled...who cares.

Now you're whining like a 5 year old girl who dropped her ice cream cone.

Oh I'll show you hostility!!!!!

To be completely fair, I personally have never ran my car, but hope to shortly.

However those times are fairly universal.

And just so no one bitches, I never claimed to know exactly what my car runs or puts down, just estimating.

I really want to get to the strip though.. I'm tracking down a misfire though right now

Edit: Forgot to mention that the old owners DID run the car with just the flowmaster, and ran it at a 13.9. He didn't mention trap speed. I'll contact the old owners to try to get a timeslip. But I havn't ran it, so I used times that I know my car is faster than.

Because think about it, 3.4's IROC has lots of mods and is alot faster than stock, probably without tuning putting him somewhere around 13.9 or so. And I only pulled a car on him to 110, which is about 10 MPH +/- 1 mph past what I should trap. So we're pretty even in the quarter, with me just nosing past him. Over 100 MPH though his TPI kills him.

So those estimates are really conservative, but still just estimates. I guess he's in denial that I beat his million dollar car?? (inside joke)

EDIT again: Bench racing at it's finest.

I was under the impression from previous posts that you had dyno slips and a few track times. None the less I would say your estimates on power are accurate. You should see nothing less than 250 at the wheels (that is unless your missfire is serious).

Yeah, that's what the whole thing was about. I was estimating how much power I might have and what I might run and he didn't believe it. I havn't ran yet due to this misfire..

I thought it was the ICM, so I replaced it and it still misfires a bit. Only happens when the engine bay gets heat soaked, it's very odd. I'm thinking the coil next, then if that doesn't fix it I'll tear the opti apart.

but the old owners did run a 13.9@99 with less mods than this, I just called and confirmed that run.

told u the car never been at the track or dyno thats way i don't beleive him. fly89gta y are u trying to start sumthin?? me and tone (urbanhunter) have been best friends for 6+ years ya ***.

btw tone when i was in the shower 15min ago molly showed up and droped off my sweater and somebodys watch and left a note gimme a call for details

I know Just felt like telling you that you're whining lol

this is just a dick measuring contest mostly.. dont know how this spilled onto TGO!

check your voice mail.

Oh man, too easy to comment

ROFL just noticed that myself. HEY LOOK OVER THERE---->

the corvette LT1's have the A/C unit on the opposite side than the Fbody A/C units...... LOL

the power is there to run those times, just need to work on the 60 foot time/launch... but thats still quick for a bone stocker