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Discussion Starter · #1 ·
I am starting to put prices next to certain parts that I am going to buy. I'm going to start with the heads. Are there any other websites online that I can go to so I can check out some cylinder heads? I've been to www.yearone.com and www.summitracing.com. I know www.edelbrock.com and www.gmpartsdirect.com has some to. I want to check out both the LT1 and LT4 heads. I know the LT4 are better performance wise because they are aluminum and light, but the LT1 are more reliable because they are iron. So, I have to make a choice on which ones to get. I know mostly everyone recommends the LT4. Right?
 
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Discussion Starter · #3 ·
Aluminum does not make a better head, a better designed head makes a better head, and your lowely crappy iron heads already flow more than most LT1 aluminums, and LT1 iron or aluminum both make exellent starting points to port, heck both are very good as cast and I think you would be very suprized at how far you can go without ever removing them from the block. The heads you have now blow all the musclecar era stuff out of the water and outflow the late 80s Vette stuff by 15%, they are good enough that many will be satisfied(at least temporarily) with just a cam swap.

I would not recommend the LT4s for a 350 but many use them sucessfully, they are not better because they are aluminum, they have larger(debatably too large) ports and are not less reliable than iron exept maybe in a serious power adder application, the aluminum also requires/allows more compression because it saps more heat from the chamber. Before you go thinking that is good any heat not used to drive the piston is wasted.

Sorry but the aluminum is magically better thing irritates me, when you get down to the science of it iron is better but wether it is better enough to offset the weight difference is debatable.
 
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Discussion Starter · #4 ·
Originally posted by 96capriceMGR:
I would not recommend the LT4s for a 350 but many use them sucessfully, they are not better because they are aluminum, they have larger(debatably too large) ports
It's not the port volume that makes a head lazy at low rpms but rather the cross-sectional area. Also, compression ratio makes a big difference in port velocity. My aluminum LT1 heads, ported by Lloyd Elliot, have 200 cc intake ports which is 10 cc more than the LT4s. However, because of a good head work and 11.3 compression ratio, my car is running much stronger throughout the powerband (including the rpms). This is confirmed by both, seat of the pants and 60' times.

However, if the port volume is too small, the car will be a dog at high (5500+) rpms.
 
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Discussion Starter · #5 ·
Kendrick, there are many choices out there... LT4, Trickflow, Edelbrock, Ported stock iron, Ported Stock aluminum, LLoyd Elliot ported stockers, Combination Motorsports ported stockers, etc etc....

If I were to do it all over again, there might be a chance that I'd pick up a Lloyd Elliot power package which includes HEADS & CAM.

Check out these packages copied from another thread:

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LE1 cam pulls from 2000 to 6200 RPM and should make 380-390 RWHP with matching heads, 30 lb injectors, 52 TB, 1 3/4 LTs, No cats, good tuning, etc. The heads are ported using stock valves, performance valve job, back cut valves, CM 612 springs, retainers and locks, milling, cleaning and assembly. These heads flow about 255/180 with a 195 cc intake port and stock LT1's flow about 215/150 with a 170 cc intake port.

Heads and cam are $1100 (plus shipping). This has the RPM range of the Hot Cam or CC 305 cam but makes more HP and TQ through out the entire RPM range. This will work with any gear and converter but the track times will be better with a stall and some gear.

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LE2 cam pulls from 2200 to 6500 RPM and should make 400-420 RWHP with matching heads, 30-36 lb injectors, 52-58 mm TB, 1 3/4 LT's, no cats, GOOD tuning, etc. The heads are ported and machined for larger Ferrea 2.00/1.56 valves, Comp 987 dbl springs, TITANIUM 10 degree retainers, locks, locators, milling, cleaning and assembly. These will flow about 270/190 with a 205 cc intake port.

Heads and cam are $1600 (plus shipping) and will need GOOD tuning. This has the RPM range of the CC 306 cam but will make more HP and TQ at peak and across the board. The REAL difference will be the LE2 cam will make TQ in the 2500 RPM range and the cc 306 doesn't start until way past this.

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LE3 cam pulls from 2600 to 6800 RPM in a 350 (2300 to 6500 RPM in a 383) and should make 410 to 430 RWHP with matching heads, 36-42 lb injectors, 58 TB or mono blade, GOOD tuning, etc, etc, etc. These are the same heads from above but with Comp 977 springs instead of the 987's. These are stronger and will also need Comp R lifters to handle the spring pressure.

Heads and cam are $1700 (plus shipping) and will need GOOD tuning. This cam is similar to the GM 847 cam but makes about 10 more HP at peak and starts making HP sooner. Makes more HP and TQ across the board. Needs gear and converter to work well in a 350. Pretty much a racing cam for the 350 or a good street cam that will act like the LE2 in a 383.

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Everyone has a different opinion about what is streetable and what a safe RPM limit is for their engine.

If you are looking for just cylinder heads and no cam, the heads are priced at . . . . .

$750 for the LE1 heads only
$1250 for the LE2 heads only
$1300 for the LE3 heads only

Give me a call and I can help you pick a combo that you will be happy with.

Lloyd Elliott------------------------972-617-5671------------------------Red Oak Tx 75154
[email protected]
 
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