| Author |
Message |
    
chris
New member
Username: chris
Post Number: 1
Registered: 10-2004
| | Posted on Saturday, October 9, 2004 - 3:34 pm: |       |
First off thanks to Sallee Chevrolet for providing an excellent forum and website! Now on to my situation. I have a 94 K1500 160K miles and the motor is getting very tired. After reading everything I could find my thoughts were leaning toward a vortec 383, but upon further review I don't really wish to spend as much money on the repower as what the truck is worth! I believe I will start with a fresh 350 shortblock and use a pair of new L98 heads I already have. I am also planning on headers and dual's. The tranny was rebuilt last year with upgraded componentry. I need some help with the camshaft selection. I would really like to have as much power as possible without upgradeing or replaceing my tbi unit,intake, and fuel pump. I live in IL. no smog testing issues. |
admin
Board Administrator
Username: admin
Post Number: 2089
Registered: 8-2003
| | Posted on Monday, October 11, 2004 - 11:56 am: | |
chris,
Even though you don't have any smog testing in your area, the federal laws still apply and we can't give you any advice that would help you break those laws. We can only offer you a stock replacement GM Goodwrench engine for your 1994 vehicle unless you plan on using it strictly for off road or racing applications. There are some small things like increasing the air flow and reducing engine friction you can do, but not much more then this. |
chris
New member
Username: chris
Post Number: 2
Registered: 10-2004
| | Posted on Monday, October 11, 2004 - 11:57 pm: | |
Admin,
I believe you have completely misunderstood my post. My goal is not to break federal emis. laws. The only reason I mentioned "no smog testing issues" was to not disuade someone from a recomendation that has to be within 99% of perfect tune to smog. I am not in agreement with you that a stock L98 iron head 350 motor with a good matching "legal" ie. Comp cams 12-262-4 or similar, and tbi componentry would not be within federal laws. Hopefully someone has already built something similiar that worked out well and can share some knowledge.
Regards
Chris
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admin
Board Administrator
Username: admin
Post Number: 2090
Registered: 8-2003
| | Posted on Tuesday, October 12, 2004 - 12:08 pm: | |
chis,
No, I think you misunderstood what I was saying. Isn't this fun, this could go on for days. It's illegal for us to make any suggestions to you except for using a GM Goodwrench stock replacement engine. The federal government would consider doing so as helping you break the federal emissions laws. You just have too new of a vehicle for us to say anything else legally. If you go down the path you want to take, we cannot get involved and you will be on your own. |
bogie
Intermediate Member
Username: bogie
Post Number: 119
Registered: 8-2003
| | Posted on Tuesday, October 12, 2004 - 3:26 pm: | |
Chris, the engine you propose is close to fine. While not technically legal from an emissions standpoint, it should at least be pretty clean and efficient. The issue with SMOG is that a manufacturer either OEM or aftermarket must test qualify an engine or a product for sale. If this hasn't been done (assumptive that it passed) then it's not legal. A classic is the Vortec head, everybody and their brother has put these things an any engine that would sit still long enough to torque the bolts. These, however, are all illegal for pre 1996 engines; as this head has never been qualified for anything besides 96 and up production.
So you're building an engine configuration that while consisting of parts qualified for various applications were never brought together and qualified in the configuration you wish to build, therefore, it's technically illegal. The heads were qualified for use on an engine that used TPI rather than TBI and was installed in a passenger car rather than a pickup, and you're using heads from a vehicle earlier than your pickup. The law on dating states that swaps of qualified parts or complete engines/drivetrains must be of the same year of the vehicle's manufacture or newer. So these are the rubs that Sallee can't legally deal with in providing advice.
However, you're path is pretty good. Your bottom end 350 will accept the L-98 heads, from what you seem to say these are cast iron rather than aluminum. The performance gain over the swirl ports you have will be marginal, they're (the L98) really not that good. The same performance can be had with a little porting of the swirl-ports. The cam will make the big difference, however, the Comp 12-262-4 is really made for a TPI engine and will be a bit much for a TBI system. The reason is the TBI is very dependent on manifold vacuum for signaling the computer and these hotter cams loose a lot of vacuum which makes the ability to sense fuel requirements difficult for the computer as small vacuum changes will net large changes in fuel requirements and you start to get into the area where the signal to noise ratio begins converge on a large degree of insensitivity. If this is going to be street driven I'd recommend a milder cam somewhere between the Edlebrock 3702 which is about 195 on the intake and 214 on the exhaust at .050 lift and max opening is under .4 inch (which is a lot hotter than what the factory put in your PU) and the Comp 12-262-4. Think of the Edlebrock at the start of the range and the Comp as the rather over the top. This actually leaves quite a range to choose from and GM still makes plenty of good cams in this range such as the old 300 hp 327 cam, so called 929 cam it's timing is similar to the Edlebrock which has a bit more exhaust duration.
You will need a custom chip. Try these folks
http://www.fastchip.com/
http://www.hypertech-inc.com/
http://www.superchips.com/
http://www.kcspeed.com/
http://www.jetchip.com/
It should be pretty easy to build this engine to produce about 280 to 300 hp, which is a 70 to 90 pony gain over what you've got.
Bogie |
admin
Board Administrator
Username: admin
Post Number: 2091
Registered: 8-2003
| | Posted on Tuesday, October 12, 2004 - 4:45 pm: | |
Hey bogie,
You need to post more or you will never catch up with me.
admin
Board Administrator
Username: admin
Post Number: 2090
Registered: 8-2003
bogie
Intermediate Member
Username: bogie
Post Number: 119
Registered: 8-2003
Just kidding, but when I happened to notice how many times you have posted on the new board, it reminded me that I have never mentioned the ranking set up for number of post made by a person.
This is the ranking configuration if anyone wants to know:
Unregistered: Unregistered guest
User Level #1 (Lowest): New member
User Level #2: Junior Member
User Level #3: Member
User Level #4: Intermediate Member
User Level #5: Advanced Member
User Level #6 (Highest): Senior Member
Moderator: Moderator
Board Administrator: Board Administrator
All users, when registered, begin at the lowest user status. Users are automatically promoted based on the number of messages they post.
Automatically promote from level 1 to 2 after 10 total posts
Automatically promote from level 2 to 3 after 50 total posts
Automatically promote from level 3 to 4 after 100 total posts
Automatically promote from level 4 to 5 after 150 total posts
Automatically promote from level 5 to 6 after 200 total posts |
bogie
Intermediate Member
Username: bogie
Post Number: 120
Registered: 8-2003
| | Posted on Wednesday, October 13, 2004 - 12:29 am: | |
You know it's a time crunch that keeps me from writing more. I re-read several of my recent posts and have noticed spelling and grammer worsening as I type faster.
Typing is a big problem, I took auto shop in high school but not typing. Now I live in-front of a PC and I can't type very well and have a car full of computers I can't work on. Well at least by virtue of what I write in these columns, you can see I actually do a little of each, but there's no humor in that.
Arriving at college with little to no typing skills was a problem but it didn't take long to find girls with cars that needed work and they could type, so things worked out sort-of OK.
Bogie |
admin
Board Administrator
Username: admin
Post Number: 2101
Registered: 8-2003
| | Posted on Wednesday, October 13, 2004 - 11:32 am: | |
bogie,
I know just where you are coming from. I took a total of a half a year of typing in 5th grade and I wasn't a very good speller. I lean on word processing programs like Microsoft Word to check my spelling a grammar still and then copy and paste what I've typed into the message box, when I'm worried what I'm typing has some potential problems. About the only thing I’ve improved on is typing speed since I’ve been involved with computers. The more you do it, the better you get at it. The typing class did help, since it taught me the correct way to place my fingers on they keyboard, etc. |
chris
New member
Username: chris
Post Number: 3
Registered: 10-2004
| | Posted on Thursday, October 14, 2004 - 12:50 pm: | |
Bogie,
Thanks for the help!
I have had a few more hours to research since my original post. The heads I have are acutally the old GM 285hp 350 heads that they now sell as hp fi heads, #10125377. I have decided to go with the 330hp 350 crate engine cam #24502476. The chip guys are already burning for the crate motor with tbi usage wich should eliminate that problem. I'm still a little confused on the tbi/intake. I guess I will use my factory stuff with the addition of a fuel pressure reg. to start with and see what happens. If need be I will add a bored factory or holley 2" tbi, better tbi or single plane with tbi adapter intake, and larger injectors to get enough air/fuel into it. I will post my results in about two weeks to hopefully help others headed down this road.
Chris |
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