What would you give me as an estimate on the 1/4 mile for my car? Does high 13's seem possible?
305 TPI, bored .030 over, WC-T5, 3.73 Posi, Hooker 2460's with Y-pipe, Flowmaster 3 inch catback w/80series, Comp Cams 212/212 @.050 .444/.444 lift 112 LSA, TPIS Bigmouth Intake and TPIS runners, ported plenum, AFPR, K&N's

 

mid to upper 14's. what are you going to be running for tires?

 

agree with 14's....sounds about rights....

 

For tires I have my regular street tires.

 

This time of year, at the good tracks we have here in the NE I think you can click off a 13 second pass...even if it's a 13.99999999999

I would really invest a set of Nitto's or BFG's though, especially in this cold weather(summer can't get here fast enough).

 

1/4 mile calculator. Do a search for one on google.

 

tci website has a very nice calculator....a whole bunch of different calculators.

think it's www.tciauto.com, google though. it's under the technical section.

 

my bone stock 87' LB9 5speed IROC ran 14.9 at 94mph. if his car only does a few tenths better with all his mods either hes shifting at 3000rpms or his car is only running on 7 cylinders

 

It all depends on the tune of the motor. If running the stock prom, stock heads and are trying to compensate for a mismatch in upgrades only with an AFPR, I think that it may not be faster than a stock 305TPI 5 speed.

 

its a MAF based system so it can compensate for mods, even a small cam like his, much better than if it was a SD system. even the OBD2 cars can see gains with mild cams and no tuning

 

It had better run 13's with a decent driver You can probably shift that thing around 5400 and go 13.8 at 100mph no problem.

 

Yes,
The MAF system can compensate some. However, the cam the OP is running is not that much bigger than a stock l98 cam from that time, or an LT1 cam for that matter. Not only that, but if running the stock heads, which have smaller exhaust ports, one would want to run a dual pattern cam with higher exhaust lift and larger exhaust duration to compensate for the smaller exhaust port.
Even with the larger intake runners and better flowing base I don't see him making more than 210 hp at the wheels. Also I don't know how much better the 3.73s are making things. The longer runner design of the TPI system, even if it is a higher flowing one than stock, restricts the engine to lower revs. I really doubt that he is making power past 4800 rpm. Higher gear ratios will cause him to spin out of the power band two fast.
A MAF system can compensate some for upgrades but this compensation is no substitute for tuning. Not to mention that his setup seems a little mismatched. Thus, mid 14s is about right as far as ETs are concerned.

 

Yes,
The MAF system can compensate some. However, the cam the OP is running is not that much bigger than a stock l98 cam from that time, or an LT1 cam for that matter. Not only that, but if running the stock heads, which have smaller exhaust ports, one would want to run a dual pattern cam with higher exhaust lift and larger exhaust duration to compensate for the smaller exhaust port.
Even with the larger intake runners and better flowing base I don't see him making more than 210 hp at the wheels. Also I don't know how much better the 3.73s are making things. The longer runner design of the TPI system, even if it is a higher flowing one than stock, restricts the engine to lower revs. I really doubt that he is making power past 4800 rpm. Higher gear ratios will cause him to spin out of the power band two fast.
A MAF system can compensate some for upgrades but this compensation is no substitute for tuning. Not to mention that his setup seems a little mismatched. Thus, mid 14s is about right as far as ETs are concerned.

 

the stock 305 tpi makes decent power to 4800. he's has intake and exhaust opened up and a cam that will pull past 5K... I'd bet it pulls decent up to 5200 or so.... This is a 305ci we're talking about....

 

Stock 305 TPIs make peak power at 4400 rpm. This is with the stock TPI and a 207* int, 213* duration cam. With his intake duration at 212, 5* more, I doubt that his power curve has shifted more than 4-500 rpm from that. Intake and exhaust will help some, but I don't know that it is going to be all that much.

 

he should see mid 14s with only the exhaust changes. any other mods would make it faster than that

LB9/5speed cars came with 3.45s stock... so 3.73s wouldnt do anything dramatic like make it rev out of its powerband too quickly. with my old IROC, the stock gears would cause me to go thru the traps at 4300rpms. with 3.73s, it would only increase rpms to about 4700rpms, right were a stock style intake manifold TPI needs to be at the finish line. they would also make the car leave the line slightly harder, taking advantage of the TPIs down low torque and getting better 60fts... ultimately leading to better E/Ts than mid 14s

obviously his cam isnt quite right for his setup, but to say it will see no gain or even lose power is just not true. tuning will always optimize things, but for small mods like the OPs, its not 100% necessary to see a gain from his work

of course all this is just in theory, as a real drag racing session would let us know exactly what the car is capable of. it will also come down to the drivers ability, weather, and track prep

 

this is all true....and you should shift 3-500rpm after Peak power....so with and approximate 47-4800rpm peak, he should shift around 5200rpm..

 

you dont want to shift everytime above peak power, just go through the traps slightly above peak power

 

You are right about that. These are only estimates that can provide a range for the OP of what to expect. The best way to find out is on the track.
It is a matter of preference of either standing on the conservative side of these estimates, or the optimistic side, prior to finding out on the track.

 

For what reason do you think that my cam isn't suited for my application? What size cam would have been a better choice? Thanks for the responses so far.

 

If you are running the stock heads (416 cast number with perimeter bolt valve covers) the exhaust ports are smaller than the intake ports. They flow about 180 - 190 CFM on the intake side at the .444" valve lift that you have and only about 105 - 110 CFM on the exhaust side due to the smaller exhaust port. In order to allow for the exhaust gasses to escape more efficiently, a split pattern cam is more desirable, where the valve lift and duration on the exhaust side is higher than it is on the intake side. This will allow more time for the exhaust gasses to escape and thus help with better cylinder filling.