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Discussion Starter · #1 ·
I am guessing that this is not a terribly difficult thing to install. I have an L03. If I used an all stock motor(besides intake and exhaust and of course nitrous) would this give my car a noticable performance increase? Are there any complications invovled in installing them? How much are they?
 
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Discussion Starter · #2 ·
They are not that hard to install, but with your valve springs, and if they are stock, might not hold the extra lift. I would change those with 1.6 RR.
Also if they did, it might help out on the Nitrous because of the tad bit extra duration and the extra lift.

I would see if Combination Motorsports has them for your car. There springs are top notch.
 
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Discussion Starter · #5 ·
I would consider myself a less than average wrench turner and have never had the valve covers off a car before. Just replaced my valve springs and installed 1.6 rr's last Friday on my LT1.

Bought a valve spring compressor from Snapon.

Printed this webpage and some of the links (referenced it often)
http://shbox.com/ci/valve_spring_swap.html

He is not kidding when he tells you to get a telescoping magnet, I would not try this job without one.

Now, THIS IS IMPORTANT: YOUR LO3 MIGHT NOT HAVE ENOUGH COMPRESSION TO USE THE "TURN THE PISTON TO TDC AND LETTING THE VALVES DROP" METHOD. USE COMPRESSED AIR OR FIND SOMEONE WHO HAS DONE IT ON THAT MOTOR.

The hardest part for me was removing the original valve covers. Alternator, air pump fittings, brake booster hose had to be removed to get them off. Along with moving some wiring harnesses out of the way. Still tough to wrestle out with the heater hoses behind #8.

The work was not hard, just time consuming. The number 8 cylinder took probably 1/3 of the entire time to get the damn keepers back on (very frustrating). I took my time and had to go back under both covers after 50 miles to find and correct a loose rocker (I had forgotten to lock one of the CC rr's, #6 exhaust)

3/4 turn preload on the rockers and LT4 valve covers (which went on a hell of of a lot easier than the stockers came off) and the valve train is quieter than stock.

Took about 7 hours (including going back in to repair my error) from start to finish. Plenty of breaks, and double checking everything, except apparently the #6 exhaust rocker. It took me about 5 cylinders before I trained my fingers to do the keepers in timely manner. I could probably do the job in a lot closer to 3 hours now that I have done it once. I spent a long time watching valves and spinning the motor to ensure I was at TDC for each spring swap and rocker adjustment. My 170K+ valve springs were in sad shape. 3 of them could be compressed somewhat by hand. Car runs a lot better now, I think I picked up more improvement from the springs and rockers than I did when the 3.73's went in. As I said, the stock springs were not controlling the valves very well at all. Putting in new valve seals was a no-brainer as well. Adds about 30 seconds to each spring replacement.

Again, I do not know if you can use the TDC method on anything other than the LT1, so check into that.

I got http://buy1.snapon.com/catalog/pro_det.asp?search=true&item_ID=16398&PartNo=YA3271&group_id=1575&store=snapon-store&tool=all
and chucked the plastic knob to the side. Got out the 5/8" socket and rachet and then went to work.

-D
 
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Discussion Starter · #6 ·
Here's a little tip for those pesky keepers. I used a SMALL dab of petroleum grease to help hold them in place on the valve stem while I released the spring tool.
HTH! :D
 
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Discussion Starter · #7 ·
Thanks for the tips guys. I'm gonna probably post on a third gen camaro forum about this, because they have a lot of expertise on the L03.
 
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Discussion Starter · #9 ·
I'm not sure about the specs of the stock L03 cam, but I think they MAY be in the neighborhood of 350/384...Again, I am not sure the specs on the spring either, but they might have used the same springs that were on the 350 version, which are 413/428. If this is the case, the 1.6's might keep the lift under what the springs can handle. I guess you could always try. Like you said, the 3rd Gen guys work a lot with theses motors and probably know a lot more about them than we do.

Troy
 
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Discussion Starter · #10 ·
I am looking to replace my cam with the 845 which seems to be the way to go and 1.6 RR and new valve springs. What is the best brand and place to get the RR and springs? Is the 845 cam a GM cam?
 
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Discussion Starter · #11 ·
Springs, you will have to go with the CM springs since they will work with the iron heads. Rockers, you can also get from them, or any other place for that matter. The 845 is actually a Crane Cam, but has the GM label.

Troy
 
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Discussion Starter · #12 ·
and with the 845, most will tell you to go with staggered 1.6/1.5 intake/exhaust to avoid putting too much lift for the studs.
 
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Discussion Starter · #13 ·
dont waist your time on the lo3 i had one there not anything worthwhile, peanut cams, crappy heads, and ohhh yeah 305ci

save your money do a motor swap if you want hi-po, if you want daily driver reliability keep the lo3 there good everyday drivers, hard to kill
 
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Discussion Starter · #14 ·
hmmm let me think about this...

$90 + 5 hours for rockers or $5000 including labor for an LT1 swap...

I'm posting for information, not skepticism. I got this car for free, I wanted 14's. I haven't spent more than a grand so far on unncessary mods, and my car can out quarter your stock LT1. On the juice it puts out decently over 300hp and decently over 450 ft-lbs. This car is about learning about SBC's for me, and having a good time while doing so. Furthermore, I've gotten a decent amount of positive feedback. My cold air design was novel and has been copied numerous times all over the country. The reason we're all on this forum is because our automotive tastes are unusual. 9/10 car people don't like the caprice or the impala. I'm certainly no exception and I have no qualms with modding an engine that will readily double it's power on nitrous without throwing a fit. It's nice having a fast car and not being in debt. Especially while being a full time student.
 
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Discussion Starter · #15 ·
Just out of curiosity, what does the car run in 1/4 using the NOS. I know you said 14's but high, mid or low? I'm not here to start anything. I'm just curious. Thanks


Matt
 
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Discussion Starter · #16 ·
Should be low 15's to high 14's. "The bambinator" ran a 15.1 on a 15bhp smaller shot than mine and with a better exhaust back in the mid 90's. Traction is a big issue here. The car produces a little over 300hp presumably at below 4500 rpm. That equates to a whole lot of torque, and a whole lot of tirespin on my allseasons and pegleg. If I had slicks and a non c-clip rear I could probably do mid to low 14's. This may seem like too much power for the times I'm looking at, but keep in mind the traction issues, and 2.56 ratio rear end. I beleive my trap speeds will be significantly higher than would be expected for my ET's. You'll notice in my sig that I've listed a 7.1 0-60. This was using a gtech and with consistently crappy launches. Right now I beleive that with it's 255's and posi, a stock impala SS would beat me to 60, but most likely lose in the quarter. That's part of the reason I'm looking into these rockers, I'm trying to move the torque up in the RPM range.

Hope that helps.
 
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Discussion Starter · #17 ·
Nothing wrong with that. Gotta Love Nitrous when used on the right car. I remember trying to get my Roadmaster to do 0-60 times; it's basically impossible without a posi and stock tires. But that's pretty much true for any Lt1 powered non posi car.

Have fun modding.

Matt
 
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Discussion Starter · #18 ·
Originally posted by r3pp3r:
.... $90 + 5 hours for rockers or $5000 including labor for an LT1 swap...
Which would mean it would be cheaper to buy and actual LT1 car, rather than to do an engine swap.

BTW, if you keep the stock cam and use the 1.6 stamped rail-type rockers, then just get stock new springs and retainers for the iron-head Bcar LT1. You don't need anything fancy or expensive for springs given that the lift will be very modest. And delete the valve rotators. That will lighten the valve train.

.... I got this car for free, I wanted 14's.
Free is very good, and you're probably close to the 14s.

I haven't spent more than a grand so far on unncessary mods, and my car can out quarter your stock LT1. On the juice it puts out decently over 300hp and decently over 450 ft-lbs.
Uhhh, probably not. The stock LO3 was rated at 170 fwhp and 255 fw ftlbs. If you are using a 135 hp NO2 shot (which seldom means you get the whole 135 btw), then you'd be in the 300 fwhp (optimistic) neighborhood at 4500 rpm, but only around 310 (optimistic again) fw ftlbs at 2200 rpm. The hp gain at 2200 rpm is going to be roughly half of what it is at 4800 rpm, so the torque boost isn't going to be as much as you think (hp = torque*rpm/5252).

So you might be looking at around 310 ftlbs and 300 hp, but more realistically it will be around 270 hp and 300 ftlbs. So the "135 shot" might only behave like a 100 hp gain at the flywheel. With those type of numbers you might break into the 14s. The hp is above a stock LT1 Bcar but the torque is less.

With that said, a few more cheap mods and you should be into the 14s easily.

This car is about learning about SBC's for me, and having a good time while doing so. .... My cold air design was novel and has been copied numerous times all over the country.


Novel, yes. Copied? Not so sure about that. And Billy's is a lot slicker from a factory aesthetics viewpoint. Further item: Dave Macdonald did one the same way at least 5 years ago. His pix is posted on the Yahoo website under either the GM TBI group or the 9C1 group, probably under the pictures folder. It's also discussed in in this thread.

Dave is still around; I know he posts on the INEGMA website and his profile is <a href="http://www.inegma.net/mb/index.php?s=7ba01c6fa9b495f9444f4bd7ff671f09&act=Profile&CODE=03&MID=19" target="_blank">here
</a>

All of these dual snorkles are outgrowths of the factory dual snorkle aircleaners that most of the Big Three used back in the 70s, 60s and probably into the 50s too.
 
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Discussion Starter · #19 ·
You raise some good points. I was simply trying to appropriately deal with yet another anti-L03 fanatic (I'm tired of the harassment, just let me mod my car in peace!!!!). I'll let the point about the intake go, because I was pretty much pulling that out of my a$$ in the first place(BUT billy said that he gets quite a few emails about his setup inspired by my design). You have a point about my predicted hp/trq numbers, and my calculations seem to have been off. HOWEVER, recalculating I have come up with the following numbers:

You said yourself that I was realistically putting out [email protected] 4500 rpm.

tqNOS(4500) = (270hp)(5252/4500) = 315.2 ft-lbs

Ok that's all good. At 2500 RPM (where nitrous engages) my car puts out 250 ftlbs NA (255 @ 2400 so im making a rough estimate). For hp at 2500:

hpNA(2500) = (250ftlbs)(2500/5252) = 119.0hp

I'll use your estimate for boost at that RPM of 50hp:

hpNOS(2500) = 119.0hp + 50.0hp = 169.0hp

Now for torque at 2500 on boost:

tqNOS(2500) = 169.0hp(5252/2500) = 355.0 ft-lbs

So realistically (pessimistically) I think [email protected] and [email protected] is a better rough estimate. It simply doesn't make sense for a lower revving engine to have more hp and less tq, than its higher revving counterpart IMHO.
 
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