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Discussion Starter #1
question for the 305 guys what mods have you guys done to you 305's what 1/4 mile are you's runnin im trying to figure out what i'm doing wrong i know the 305 has more potential than 16.5-17.5 at the 1/4 mile any tips thanks

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92 CAPRICE LTZ stock 305,3.23gears,pete jackson gear drive,K&Nfilter,duel exuast,ssgrille,clear fronts and rear lights,msd 8.5 wires x4plugs
DRIVE IT LIKE YOU STOLE IT
DONT DRINK AND DRIVE YOU WILL SPILL YOUR BEER
http://hometown.aol.com/bbodyltzn/
 
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Discussion Starter #3
You might also try a new torque converter and since you still have the stock clutch fan (looked at your webpage). Pull the belt for it and you should pick up a few tenths. Maybe even disconnect the front swaybar (or remove it totally).

If you really want to go big, get a new cam! A stock LT1 or LT4 cam is a great cam for the 305.

Also, I see you have yet to join the GM_TBI listserv. http://groups.yahoo.com/group/GM_TBI
Lots of help for you there!


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Che§ton Phillips - AIM:Impalaitis
'96 BBB Impala §§ "ADIOSS" & '91 white Caprice 'n0n 9c1' w/L03
 
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Discussion Starter #4
does the stock clutch fan really rob that much?
 
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Discussion Starter #5
On of the car magazines(Car Craft May 2000) I read did a dyno test on a 400hp+ smallblock. The worst mechanical fan (fixed) robbed 45HP over an electric. I am not saying the stock cluch fan is that bad but there is a reason Detroit switched to electric. Didn't the 96's with the towing option and mech. fan get a 250hp rating instead of 260hp.

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Dwayne Jennings

Body bushings, stiff rear Bilstiens, stock size K+N, polyurethane endlinks, Jacobs ignition
,Moog idler arm, T/B bypass, GM deep tranny pan, Impala wheels are in will go on in spring

[This message has been edited by 96capriceMGR (edited April 08, 2001).]
 
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Discussion Starter #6
<BLOCKQUOTE>quote:</font><HR>Originally posted by BBODYLTZN:
question for the 305 guys what mods have you guys done to you 305's what 1/4 mile are you's runnin im trying to figure out what i'm doing wrong i know the 305 has more potential than 16.5-17.5 at the 1/4 mile any tips thanks
<HR></BLOCKQUOTE>

I've tried to help you out before on your 305; you need to go back and read all those posts because the answers (besides using a higher stall torque converter) are all there.

I'm going to summarize your 305 problem for you, and I'm also going to give numbers for the 350 (LO5). I used a computer program called CarTest to come up with these numbers and they are very representative and believable.

I modeled a '93 Caprice with LO3, 2.56 rear end, 4200 lbs, everything stock. I also modeled a '93 Caprice with LO5, 3.42, 4200 lbs, also stock. I call both of these STOCK cases.

I then modded BOTH, first with cheap-simple mods (cold air, better exhaust, TBI mods via ThirdGen.org, shift kit) to show just what that will get you. I call this the MILD mods case.

I then went one step further by doing a gearswap (to 3.73 for both of the above cars, and I retained the cheap-simple mods), and by doing an F/Y LT1 stock cam swap. I call this the MILD+1 case.

The STOCK LO3 305 went from 170 [email protected] and 255 [email protected], to 190 [email protected] and 265 ftlbs @ 2600 for the MILD case, and to 260 fwhp @ 5000 and 290 ftlbs @ 3000 for the MILD+1 case. Both the MILD and MILD+1 cases are really very mild because the mods and cam are quite mild.

The STOCK LO5 350 went from 205 [email protected] and 300 [email protected], to 220 [email protected] and 310 ftlbs @ 2500 for the MILD case, and to 290 fwhp @ 5000 and 340 ftlbs @ 3200 for the MILD+1 case. Again both the MILD and MILD+1 cases are really very mild because the mods and cam are quite mild. Also note that the MILD+1 case is very similar to a slightly modded 94-96 LT1 Bcar.


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LO3 STOCK
rear end: 2.56
cam: stock
trans: stock
0-60: 9.4 sec
0-80: 16.6
1/4 ET: 16.8
1/4 trap 80.5 mph
top speed: 126 mph in D
-------------------
LO3 MILD
rear end: 2.56
cam: stock
trans: shift kit
0-60: 8.4 sec
0-80: 14.9
1/4 ET: 16.3
1/4 trap 83.6 mph
top speed: 131 mph in D
-------------------------
LO3 MILD+1
rear end: 3.73
cam: F/Y LT1
trans: shift kit
0-60: 7.0 sec
0-80: 12.3
1/4 ET: 15.5
1/4 trap 89.4 mph
top speed: 147 mph in OD
----------------
LO5 STOCK (9C1)
rear end: 3.42
cam: stock
trans: stock
0-60: 8.2 sec
0-80: 15.1
1/4 ET: 16.4
1/4 trap 83.1
top speed: 133 in OD
-------------------
LO5 MILD (9C1)
rear end: 3.42
cam: stock
trans: shift kit
0-60: 7.7 sec
0-80: 13.7
1/4 ET: 16.0
1/4 trap 85.7
top speed: 136 in OD
---------------------
LO5 MILD+1 (9C1)
rear end: 3.42
cam: F/Y LT1
trans: shift kit
0-60: 6.6 sec
0-80: 11.5
1/4 ET: 15.2
1/4 trap 91.4
top speed: 150 in OD


What can be learned from this science exercise? The LO3 CAN be made to run well, and essentially even with a stock 94-96 LT1 car, but you will ONLY get there if you do more than cheap/simple bolt ons to the intake and exhaust.

The LO3 can be made to run even better than 15.5 @ 89.4 mph if you do more than what I suggested. I think an LO3 can go into the 14s without that much trouble, because there are Fcar owners with LO3 running low 14s or better. The weight difference would equate to 0.6 to 0.8 secs longer ET from the Fcar to the Bcar.

You also said you believed that there was more to 16.8-17.5 quarter mile performance for an LO3 Caprice in the quarter, and that suggests you ran the car recently on the track and got 16.8. Well, those numbers are right about where an LO3 Caprice LTZ should be with a few bolt ons and you in the car. And you are right -- there CAN be more performance to the LO3 but not with what limited mods you've done to it.

If you really want the car to go faster ON A BUDGET (as you have said before), you should learn from the LO3 Fcar owners on the ThirdGen web site, AND you MUST do a cam swap. Your LO3 will never give you the power you want until you do that at the minimum.

You can also see what the 350 would do for you. Actually the 350 performance with the MILD+1 mods would be better than I have shown because the torque band is actually better than I had modeled, but I didn't want to fuss with it. What I ran for these six cases is enough to prove the point.

You can't WILL your LO3 to go much quicker than it has, with the mods you have. You're gonna be stuck in the high 16s until you do some real mods; for a STOCK LO3, that means the cam is the problem, and the heads would be next. You need to make up for the 45 cubic inches that you are missing. You need to change the cam, and that CAN be a cheap mod IF you do the work yourself; and you should try to do something to the heads.

You could use nitrous, but remember that all the money you spend on the setup, plus the cost of refilling the bottle, could be spent on either mods for the 305 (mods that could be later used on a 350), or on a 350-cheap-buildup while the 305 is still in the car.

The cam is a must do, for you, and I'd get Vortec heads and the appropriate intake too. That will put you into the 14s IMO, and those parts could also be used on a (later) 350 if you chose to go that way.

This is my last post on making your 305 faster --- all the initial info you need has already been posted by me or others on this and the http://www.thirdgen.org forum.

FYI and FWIW. - Ken



[This message has been edited by kdrolt (edited April 09, 2001).]
 
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Discussion Starter #7
Two words: Crate Motor

You can get one with ample power for a very affordable price now.
 
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Discussion Starter #8
ok today is tuesday the 10 im going to the shop thursday and im putting in a 4.10 gear that should help a lil huh ha ha ha what do you guys think about a 4.10 gear

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92 CAPRICE LTZ stock 305,3.23gears,pete jackson gear drive,K&Nfilter,duel exuast,ssgrille,clear fronts and rear lights,msd 8.5 wires x4plugs
DRIVE IT LIKE YOU STOLE IT
DONT DRINK AND DRIVE YOU WILL SPILL YOUR BEER
http://hometown.aol.com/bbodyltzn/
 
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<BLOCKQUOTE>quote:</font><HR>Originally posted by BBODYLTZN:
ok today is tuesday the 10 im going to the shop thursday and im putting in a 4.10 gear that should help a lil huh ha ha ha what do you guys think about a 4.10 gear
<HR></BLOCKQUOTE>

94-96 LT1 Bcars that go to 3.73 ring-pinion ratio from 3.08 improve by 0.15 to 0.20 secs typically in the quarter. So your 16.8 sec quarter mile ET with 3.23 *might* drop to 16.6 sec with 4.10. Of course, with your flow-challeged 305 (stock heads), you'll only be taking the engine out of its useful torque band (idle to 4000 rpm) sooner with 4.10s.... so YOUR car might actually be slower.

PT Barnum, your turn. - Ken



[This message has been edited by kdrolt (edited April 10, 2001).]
 
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Discussion Starter #10
so then what should i do then go with the 4.10 or the 3.73 im now saving a lil $$$$ for the LT1 cam i'll be getting soon but im more conserned about the rearend because its making some noises it shouldnt be making so i want to get the rear done asap if thier going to have the rear open i might as well have the gear changed to save some time and money what do you guys think thanks

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92 CAPRICE LTZ stock 305,3.23gears,pete jackson gear drive,K&Nfilter,duel exuast,ssgrille,clear fronts and rear lights,msd 8.5 wires x4plugs
DRIVE IT LIKE YOU STOLE IT
DONT DRINK AND DRIVE YOU WILL SPILL YOUR BEER http://hometown.aol.com/bbodyltzn/

[This message has been edited by BBODYLTZN (edited April 10, 2001).]
 
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<BLOCKQUOTE>quote:</font><HR>Originally posted by BBODYLTZN:
so then what should i do then go with the 4.10 or the 3.73 im now saving a lil $$$$ for the LT1 cam i'll be getting soon but im more conserned about the rearend because its making some noises it shouldnt be making so i want to get the rear done asap if thier going to have the rear open i might as well have the gear changed to save some time and money what do you guys think thanks
<HR></BLOCKQUOTE>

If the rear end is making noises, here are the most likely reasons:

- low fluid;

- low fluid and low GM posi additive (you have an LTZ so that means you got G80 posi and the GU5 3.23 rear end);

- outer axle bearings grinding grooves into the axles, most likely on the passenger side, and possibly on the driver's side. This happens because of low fluid level in the diff and because GM used a diff cover gasket lacking the holes to allow splashed fluid from the inside of the diff cover to run into the case spreader holes and thereby lube the axles. Some of the lube on the axle shafts works its way outward to the outer bearings.

If *I* were you I would open the rear end cover (which also drains the rear end) and inspect the magnet. I'd also measure the amount of fluid that came out (which will tell you if the fluid was excessively low). I'd then use either the new GM diff cover gasket or the Felpro RDS 55028-1 gasket, and in both cases I would use an X-Acto knife to make the gasket holes the same size as the L & R case spreader holes on the rear housing. I'd then refill with GM fluid and 1 bottle of the GM posi additive. IF the noise that you were hearing didn't go away, THEN I would go ahead and have a shop work on the rear end. Otherwise, if the rear end quieted down, I'd leave it alone and not change the gears.

To do the above you need the correct metric socket for the diff cover bolts, a large drain pan, 2 liters of GM diff lube, and 1 bottle of GM posi additive (get the correct one for the Caprice), plus a diff cover gasket. These items will cost you less than $25. If this works, you'll save a few hundred on having your rear end taken apart. And if you have decent wrenching skills, you could also pull each axle out by a few inches to check the outer bearing surfaces. To do this you need to remove a few locking items within the rear end, and for that you should look at the FSM.

I wouldn't rush into having the gear swap done, because rear end noise that you hear is not uncommon and it is often fixed by a drain and refill operation, and by adding the GM posi lube. I urge you to try this BEFORE you have a shop do a gear swap. You might still need to have the rear end done if it still makes noise, but the 3.23 is FINE for now and 3.73 or 4.10 are not going to help you. Especially right now.

Now if you are really hard over on getting the gears swapped, remember what I said. They might not make the car any faster because your engine is tuned to provide good torque from idle to around 3500-4000. If you had to choose between the 3.73 and the 4.10, I'd say use the 3.73 ---- but be warned, I doubt it will make the car any quicker in the quarter.

I'd rather see you try the inexpensive do-it-yourself work on the rear end (drain, use new gasket, refill) to see if it solves the noise problem, than have you have the rear end rebuilt when it might not need it. The money you don't spend on the rear end could be put towards the engine.

How many miles are on the car right now, and how many were on it when you bought it?

BTW, you should be able to get an LT1 cam for $50 or so. HTH, FYI, FWIW. - Ken
 
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thanks i took apart the rear end a few weeks ago axels out and everything replaced the outer axel bearings and smoothed the axel ends put a new felpro gasket and put new fluid some stuff from work that is suposed to have some aditive already in it and the noise went away for a few days and then came back louder so im going to a good shop here in chicago that all my friends say is a realy good shop im going to have them take a look at it and change the gear while they have the rear open might as well right

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92 CAPRICE LTZ stock 305,3.23gears,pete jackson gear drive,K&Nfilter,duel exuast,ssgrille,clear fronts and rear lights,msd 8.5 wires x4plugs
DRIVE IT LIKE YOU STOLE IT
DONT DRINK AND DRIVE YOU WILL SPILL YOUR BEER
http://hometown.aol.com/bbodyltzn/
 
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i bought the car with a lil over 82k it now has just over 92k and runs like a charmyour right i think i'll buy the LT1 cam first and see what that gives me PEER PRESURE AINT IT A BITCH what to do what to do ???????????im so confused i would post a pic of my blue beast but i dont know how to get them up in here

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92 CAPRICE LTZ stock 305,3.23gears,pete jackson gear drive,K&Nfilter,duel exuast,ssgrille,clear fronts and rear lights,msd 8.5 wires x4plugs
DRIVE IT LIKE YOU STOLE IT
DONT DRINK AND DRIVE YOU WILL SPILL YOUR BEER
http://hometown.aol.com/bbodyltzn/
 
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<BLOCKQUOTE>quote:</font><HR>Originally posted by BBODYLTZN:
thanks i took apart the rear end a few weeks ago axels out and everything replaced the outer axel bearings and smoothed the axel ends put a new felpro gasket and put new fluid some stuff from work that is suposed to have some aditive already in it and the noise went away for a few days and then came back louder so im going to a good shop here in chicago that all my friends say is a realy good shop im going to have them take a look at it and change the gear while they have the rear open might as well right
<HR></BLOCKQUOTE>

On the Felpro: the holes in it are SLOTS, so I suggest that you get another one and cut the slots into circle holes, using the diff housing as a template and pushing the gasket against the hole edges so they make a nice indentation mark on the gasket.

Mileage - That's relatively small miles (82k, 92k) for bought and now, so if the axle bearing surfaces looked good then you are lucky. It also probably means that the rest of the rear end is ok. The posi might be tired however.

ON THE FLUID, IMPORTANT --- you used lube that "already has additive" according to your post, but it's now common knowledge that it won't stop the noise. YOU NEED TO USE either GM diff lube AND the correct GM posi additive, or use a synthetic lube (I used Mobil-1) AND STILL USE the GM posi additive. If you believe nothing else, believe this --- re do the gasket, use either GM or synthetic diff lube, and put in 1 or 2 bottles (start with one) of the **correct GM posi additive**. The noise WILL go away.

You may not need to have the rear end taken apart RIGHT NOW, which will save you some money. Keep the 3.23 for now.

BTW, putting in a double roller timing chain & sprocket set (when you do the cam) is a very good idea and you should be able to get a Cloyes set up for under $30 from Summit.
- Ken
 
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Discussion Starter #15
where could i get a LT1 cam and when i put the LT1 cam would it be a must to put in new lifters or could i get by with the stock ones if i do which set do you think i should go with and thanks for all this very helpful info.

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92 CAPRICE LTZ stock 305,3.23gears,pete jackson gear drive,K&Nfilter,duel exuast,ssgrille,clear fronts and rear lights,msd 8.5 wires x4plugs
DRIVE IT LIKE YOU STOLE IT
DONT DRINK AND DRIVE YOU WILL SPILL YOUR BEER http://hometown.aol.com/bbodyltzn/

[This message has been edited by BBODYLTZN (edited April 11, 2001).]
 
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Discussion Starter #16
Hey, I too have a question about the LT1 cam.
How does the pin in the end of it affect
installation on a non-LT1 block? Also if it
would work, than a LT4 cam should too, or am
I streching it? I am trying to get the most
out of the LO3, but I have a good LO5 I just
pulled out of a 9C1, with the police LO5 cam
and heads. I was wondering if it would be worth adding all the LO3 mods to the LO5 and drop it in?
Any help would be great.
 
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<BLOCKQUOTE>quote:</font><HR>Originally posted by 93TBIGuy:
.... How does the pin in the end of it affect installation on a non-LT1 block? Also if it would work, than a LT4 cam should too, or am I streching it? I am trying to get the most out of the LO3, but I have a good LO5 I just pulled out of a 9C1, with the police LO5 cam and heads. I was wondering if it would be worth adding all the LO3 mods to the LO5 and drop it in? Any help would be great.<HR></BLOCKQUOTE>

The LT4 cam is advertised by GM as a replacement cam for all roller cam engines, which IIRC is 1988+ for Gen I and Gen II small blocks. If you go looking on the web for GM Performance Parts online catalogs, somewhere it specifically says this.

So the L99, LT1 and LT4 cams will all work on a non-Gen II engine (e.g. LO3 and Lo5). To answer your question, the only item that you would need to do is to remove the pin that would be used to drive the optispark on a Gen II L99/LT1/LT4.

Note that all these cams have a gear in the back to drive a regular distributor (and hence it also drives the oil pump).

There were 2 or 3 different flavors of LT1 cam for the F and Y cars, but the specs aren't that much different between F and Y. The B car version of the LT1 cam *is* significantly different, and milder than the F/Y. Check out the F and Y car web sites and you will quickly find the details. The LT4 cam is just a whisker hotter than the LT1 F/Y cams, but the main difference is that GM used 1.6 rockers with the LT4 cam and only 1.5 rockers on all the LT1s. So the valve lift is higher for LT4 than LT1, but it comes mostly from the 1.6 rockers, not from any significant cam differences.

As far as cam choices are concerned, I wouldn't go any further than the LT1 or LT4 cam in a 305 Caprice that's street driven. The tradeoff of WOT hp for part throttle torque would be unacceptable IMO. And no, the LT4 cam isn't stretching too far.... but don't go any further or you won't be very happy with the results.

As far as your LO5 question: do it.

You CAN make the LO3 run well, but it will always be hard pressed due to the lack of 45 cubic inches. Any example of a LO3 modified engine that you could think of, you could do to an LO5 and be 20-30 hp and 50 ftlbs ahead. Do mods to the 305 that can be later used on the 350.
 
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Discussion Starter #18
Thanks for all the additional info. I have not yet added anything but a Crane Hi6 box, coil, Accel wires, cap, module, plugs. This alone made a pretty good improvement from
stock. I had the car dyno'd and it came up with 155 Hp and 234 Hp torque at the rear wheels. Everything I have is with the intent of swapping to a 350, which I didn't expect to land in my lap so soon like it did.
So here it is, I have the Edelbrock TBI intake, 350 TBI, Z Industries PROM chip, Impala SS stock dual exhaust with Flowmaster Deltaflow 2 chambers, modified air intake.
This is what I had planned for the 305, leaving the cam stock. Now I want to add all this to the 350, with 2" bore TBI and an LT1 or LT4 cam. I am trying (begging) a friend to use his shop and hoist to do all this very soon, and then dyno it again. It will be street driven, and I hope to keep up with the Impala Club of Toronto.
These are my goals and I'll post the results as soon as I wake up!!
Thanks for the info kdrolt and the others!
 
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<BLOCKQUOTE>quote:</font><HR>Originally posted by kdrolt:
... I modeled a '93 Caprice with LO5, 3.42, 4200 lbs, stock.... (and then) with cheap-simple mods (cold air, better exhaust, TBI mods via ThirdGen.org, shift kit) to show just what that will get you. ...

The STOCK LO5 350 went from 205 [email protected] and 300 [email protected], to 220 [email protected] and 310 ftlbs @ 2500 for the MILD case. ....

LO5 STOCK (9C1)
rear end: 3.42
cam: stock
trans: stock
0-60: 8.2 sec
0-80: 15.1
1/4 ET: 16.4
1/4 trap 83.1
top speed: 133 in OD
-------------------
LO5 MILD (9C1)
rear end: 3.42
cam: stock
trans: shift kit
0-60: 7.7 sec
0-80: 13.7
1/4 ET: 16.0
1/4 trap 85.7
top speed: 136 in OD
<HR></BLOCKQUOTE>

FWIW, Kevin Moore ran his 122k mile '93 LO5 3.42 9C1 at Lebanon Valley Dragway last weekend. His best run was a 15.93 @ 84.5 mph (60' time was around 2.2 sec).

His car is a touch above stock, with the main mod being a muffler delete (he kept the resonator) and he was NOT using the $0.25 mod to the FPR.

LVD is 602' above mean sea level, so the altitude correction is around 0.08 sec. So at sea level he has a car that will run 15.8s in 60-70 deg weather and probably in the 15.7s in cold weather, and his car is very close to the MILD one listed above: 220 fwhp and over 300 ftlbs.

I don't know how loud it sounds with the muffler delete, nor do I know how leaned out he was running by virtue of the muffler delete... but it does show a big jump in performance from a few simples mods. Stock LT1 SS & 9C1 cars were running low to mid 15s on the same day, same track, so he's still a 0.5+ secs off the pace... but might close the gap with a few more mods.

Lastly, I do recall on the early days of the 9C1 digest that there was a member who had a 91-93 LO5 9C1, and that he: swapped the cam, added duals (dunno if he also had headers), modded the air intake, and possibly replaced the ECM. That car went 15.7 in the quarter, so my suspicion is that it wasn't optimally tuned. Chances are that the ECM was still stock, so it could have run quicker.

This would also be consistent with the performance of Kevin's '93 running with the stock LO5 9C1 cam.

15.7 to 15.9 territory might not impress most LT1 Bcar owners, but it is even with the best Ford Crown Vic new models, and would beat ALL but the newest ones, and AFAIK Kevin's car is the fastest pre-94 non-TPI LO5 that I've heard of.

FWIW, FYI. - Ken
 
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