Keith5

Before I did my mods I ran anywhere from 74-79mph in the quarter with a ET of 16.9-17.4. Now after all of these mods I'm running 80-82.5 mph and ET's of 16.7-16.9.

Shouldn't I have gotten more speed? I can understand the bad ET's because I still have 2.73 gears, but I estimated my mph would be like 84-86 after these mods. I've got as much advance of the base timing as I can, and I have the fuel pressure increased with the BLM count as best I can get it.

I know gears aren't supposed to make a difference in your quarter mile MPH, but do you think if a combo is terribly mismatched that it would? My V6 has 3.23 gears, I'm about to swap with the v8. Do you think I will gain MPH?

NTChrist

I'd agree, you should be going faster. At least into the mid 15's, I'd say.

What kind of condition is the rest of your setup? Any ignition problems? Time for a tune up?
Where's the base timing set at?

Did you verify the casting number on your cam, to find out if it is indeed an LT1? Sounds like a long shot, but I don't think it would be impossible for somebody to be selling a peanut cam online, as an LT1.

Keith5

I didn't check any numbers, but the lobes were higher on it, and I had to hacksaw the pin down because it was longer than stock.

My ignition setup is all new. I've got a new Dist. Cab, Rotor, MSD Blaster Coil, MSD SuperConductor 8.5mm wires.

My block has 100K on it, and I do have 2.73's, but still I think I should be getting to the low 16's with those gears.

There is a little more potenital from just adjusting on the timing and the FP. My fuel pressure gauge fitting hasn't come from JEGS yet so I don't know what pressure I'm running my fuel at. I'm thinking I may need to get 350 injectors and lower the pressure back down. I also think I need one of those Vac Adjusted regulators.

Has anybody ever got higher MPH just from a gear change? I'm so slow out of the hole, I'm thinking that is my biggest problem. My 60ft times are 2.5+ without wheel spin! My last run I got a little wheel spin, that time was 2.6+.

I'm not sure what the base timing is on. I just started leaving the advance hooked up and bumping it up as much as I could. I'd say it's like on 12 or so.

REVLIMIT

hmmm...thats really strange...with your amount of mods you should be atleast in the 15's somewhere.

Buck268

Bone stock (with AC on too, ) I ran 16.4 1/4 mile, with a 60' of something like 2.3 or 2.4. I got L03/700r4/2.73 peg leg.... Maybe your running *very* lean? I have no idea how you could be running so slow with those mods. mid 15's at the slowest...

V8Astro Captain

iTrader: (1)

Get some gears and ditch the Performer TBI intake for a regular carb intake with an adapter plate.

I tried the Performer TBI and I thought it was too restrictive.

Keith5

I have used Winaldl on it. It is actually running rich at idle, and about right from 2000rpm up.

The track to go it is weird, everybody is slower there than you guys are on here. Most thirdgen non TPI 305's run low to mid 17's. TPI's run low 16's High 15's, TPI 350's are mid to low 15's, Stock LT1's run high 14's. My friend who has a new GM 305, Headers, Open Element AC delete Hardtop 5speed has run a best of 15.8.

I'm thinking of just going carb soon if I can't get it to run right. Either that or TPI/Holley StealthRAM.

Brent

iTrader: (1)

What is the elevation of the track you are running at?

Keith5

1,475 feet above sea level

Degree Of Incline
From 1 percent to 4 percent in shutdown area

http://www.bristoldragway.com/?CONTE...SKIT=807679663

Kat

iTrader: (4)

Damn that sucks.. On a dead *** 206k 305 I run 15.8's @ 84 mph Then again gears and a convertor help

Kat

kdrolt

Keith5 writes:

1,475 feet above sea level and before mods....74-79 mph... 16.9-17.4 .... after .. mods 80-82.5 mph and ET's 16.7-16.9.

Ok so you improved by 0.2 sec and 2-3 mph... but you never corrected for the altitide nor for the weather.

Using http://www.performancesupply.com/nhraconv.htm

the altitude correction is 0.9835 for ET and 1.0171 for trap speed. That would put your best at 16.4 @ 83.9 mph for the altitude correction (air pressure), but what about the temperature? How hot was it when you ran your best?

I think you do have problem(s) but some of it is that you are running at altitude and you probably ran when it was warm. So you might have a 16.2 @ 84+ mph car right now.

Shouldn't I have gotten more speed? I can understand the bad ET's because I still have 2.73 gears, but I estimated my mph would be like 84-86 after these mods.

You are close to the 84 mph trap.

I've got as much advance of the base timing as I can, and I have the fuel pressure increased with the BLM count as best I can get it.

How do you know you haven't added too much timing? At WOT, the base + advance may be causing knock, and if you have knock sensors they will back off timing and you will lose power. You might retime it back to stock as a check.

I know gears aren't supposed to make a difference in your quarter mile MPH, but do you think if a combo is terribly mismatched that it would?

Yes the 2.73 isn't helping you but you aren;t making that much torque and power so the gears aren't really the problem.

You have an LT1 cam in a 305, and you've improved the breathing on both ends of the engine.... so what have you done to improve the fuel delivery? The LO3 TBI has very small injectors, small enough to allow 170 fwhp. You engine/cam/intake/exhaust combo is aimed at 233 fwhp and it's not likely that the stock LO3 injectors can deliver anything close to 233 hp.

And remember that at WOT, your ability to sense what's happening in the engine isn't too good. I suspect that your engine is a little rich at normal driving, at idle, and at most low speeds -- but at higher rpms and at WOT, the injectors cannot delivery the fuel to match the air that your engine is pumping. Bumping the fuel pressure helped, but I doubt you can increase the fuel pressure enough to do the job, AND the fuel pump may not like pumping into a pressure higher than it was designed for. I also don't know if the fuel pump in the L03 Fcars was large enough to delivery the volume of fuel that you need.

Conclusion:So I think you need larger injectors from a 350. either a 89-93 LO5 9C1 (Caprice copcar package) or from a similarly powered mid-90s LO5 TBI truck. You may also want, or need, the ECM that goes with either of these. I think there was someone here that used the 350 ECM on a modified 305 with decent results, and you may need to do likewise.

FYI, HTH. - Ken, slurping coffee while the kids are watching cartoons

Keith5

Well the knock counter on Winaldl didn't sense any knocks under WOT with my timing being bumped up.

And now that I think about it when I got 16.9 before the mods, it wasn't near as hot that day. So if I go back to my previous best of last year, that would be 17.2@77 or 78 on a hot day.

I think I will go for the bigger injectors.

RacerXWS6

Why?

heres my mods: Edel TES headers, CATCO cat, Flowmaster, JET Stage II chip, Open Element. Now with a stock peg leg 2.73 rear I ran a 16 flat at 85 mph, and I was spinning like mad. How is it I keep seeing ppl with way more mods than I running even slower than I? Now the car has a Lunati 218/458 cam, Holley intake, and a posi 3.70 9 bolt, and about 8 degrees of advance. Which SHOULD put me solidly in the mid to low 15s. Oh and that was the only pass Ive EVER made on a dragstrip.. EVER. I prefer curvy roads, and most of my mods are in the suspension.

Im not attempting to flame anyone here Im just curious as to why the difference in my times and others with the same or more mods than I have are so different.

Keith5

That's it, I want a mustang.

Battery

I think you need a tune up or something, because there is obviously some things that are really draggin down your times.

Earlier this year when I had my v6 camaro, i ran 17.1 bone stock. I now have an 82 Z with cross-fire injection. I went to the track two nights ago, didtn get times, it was street racing. I had horrible luck, it was running terrible, Trap speed was maybe 80mph. Just last night, i let her go a couple times see if it was still running badly and i lost by a car length to a mildly modded 350 5 speed camaro. I am proud of that, and guessing when my car is running right, high 15's without a doubt.

Im a huge mustang fan as well, but they have the same problems. If your car was beat on, or is losing compression, etc etc its going to run slower, whether you have a camaro, mustang, or even a honda hehe.

You should start with the basic tune up and move up from there, find your problem and run the times you've always wanted too

Keith5

There is nothing left to tune up. It's all new.

Start naming things for a tune up, I'll see what I haven't done something.

NJ SPEEDER

tune up is not a matter of new or old parts, what he is refering to is teh chip in teh computer. if you did all these mods on a stock chip you are certainly not gonna see the full potential of the mods.
you can play with your timing and fuel pressure a bit to get the job done to some degree, but ultimate gains are only gonna come from a custom chip.
you are also not likely to see as much of a gain as someone who lives at a lower altitude. for every 10mph i gain here at sea level you will prolly only gain 8- 8.5 mph. the moral of the story is to move to new jersey and race at sea level hehe

later
tim

Pablo

iTrader: (1)

Why are you guys looking for the most complicated answers to his question?

his tune obviously has something wrong with it on a very basic level. Hell, I remember a member who shall remain nameless who had similar mods and was running 17s for a LONG time until he figured out he had a plug wire crossed and instantly catapulted himself into the low 15s. Usually the most simple answer is best. How many other cars out there have his same combination and run 14.8-15.2... lots. so its nothign wrong with the actual choice of parts.

Keith5

If I advance it an a whole lot, like to 16* or more it seems to have a lot more torque. I had it on 19* the other day and I was only getting a few knock count here and there.

Could my timing advance me messed up without throwing a code? My friend hooked up a timing light and watched it advance, he said his LG4 advance smoother a further than mine. Now I didn't see this plainly myself(his timing indicator is more hidden than mine).

If I have the timing set too low like say anywhere from 0* to 7* it will throw a code 43. I advance it anywhere from 8* up and it doesn't throw the code.

RBob

iTrader: (1)

A couple of knock counts are normal. They are also why you are not
getting the code 43. The '8746 forces knock while looking for counts.
If no counts, then code 43 is set. If it gets counts, then no code 43.

Lousy way to test the knock sensor, but that's the way it is.

And, until the ECM successfully forces knock there will not be any PE SA.

RBob.

Pablo

iTrader: (1)

You arent adjusting the timing with the EST line disconnected are you

You need to disconnect that line before you set timing. The computer advances base timing in addition to the base timing you physically set at the distributor. So if you just set timing without disconnecting the est you are essentially retarding the timing.