350h.p. LT1?????????
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From: Mass.
350h.p. LT1?????????
Hi, I have an LT1 that i am building to go in my monte but I need a little help on what parts to use.
Right now I have a stock 350 with cast iron heads, rated 260hp. Impala version.
I would like to get 350hp or close to it when I am done with the rebuild.
Here's what i got, I have basically a stock lower end, crank, pistons, etc. I would like to keep the stock heads but I will probably be porting them. I am also going to replace the cam with a larger one. I would like to keep the compression stock because i may have plans to supercharge this motor in the future.
I talked to someone who builds motors and they said the bottom end is fine for making that type of power but the fuel system wont supoort the amount of hp so with those mods I will not be able to reach 350hp.
Has anyne here done this, should I get a larger throttle body, fuel injectors, etc.
I would like to do this on a relatively cheap budget seeing how I really dont race and its mainly for show but I also want the car to have power.
Can what I want be done or am i pretty much stuck down around the 300-330 horse power range without major mods. Thanks.
[Modified by MonteSS, 4:41 PM 10/15/2002]
Right now I have a stock 350 with cast iron heads, rated 260hp. Impala version.
I would like to get 350hp or close to it when I am done with the rebuild.
Here's what i got, I have basically a stock lower end, crank, pistons, etc. I would like to keep the stock heads but I will probably be porting them. I am also going to replace the cam with a larger one. I would like to keep the compression stock because i may have plans to supercharge this motor in the future.
I talked to someone who builds motors and they said the bottom end is fine for making that type of power but the fuel system wont supoort the amount of hp so with those mods I will not be able to reach 350hp.
Has anyne here done this, should I get a larger throttle body, fuel injectors, etc.
I would like to do this on a relatively cheap budget seeing how I really dont race and its mainly for show but I also want the car to have power.
Can what I want be done or am i pretty much stuck down around the 300-330 horse power range without major mods. Thanks.
[Modified by MonteSS, 4:41 PM 10/15/2002]
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Re: 350h.p. LT1????????? (MonteSS)
Get all the LT4 stuff (intake + heads), plus the LT4 hotcam, and you will have your350hp and then some... :yesnod:
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Re: 350h.p. LT1????????? (MonteSS)
just change the cam and heads, you must get rid of the iron heads
Try the LT4 hotcam kit from GM, and some AFR 190 heads or some used LT1 AL heads.
Try the LT4 hotcam kit from GM, and some AFR 190 heads or some used LT1 AL heads.
Burning Brakes
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From: Manhattan
Re: 350h.p. LT1????????? (MonteSS)
i just read somewhere the iron LT1 heads flowed as well as the aluminum heads. I would just port the iron heads, use the LT4 hotcam, upgrade the valve springs, 1.6 roller rockers, a decent set of long tube headers, dual exhuast and you should be around 400 crank hp.
ok, here's the link http://www.fierolt1.com/lt1_lt4_headflow.htm they actually flow better than the aluminum heads, if this info is correct. a mild porting and 400hp with the hot cam will be no problem.
ok, here's the link http://www.fierolt1.com/lt1_lt4_headflow.htm they actually flow better than the aluminum heads, if this info is correct. a mild porting and 400hp with the hot cam will be no problem.
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From: Mass.
Re: 350h.p. LT1????????? (Raistlin)
yeah your right the LT1 cast iron heads actually flow better than the alluminum when ported. The only advantage is heat disapation but its not worth me spend the extra few hundred dollars on it.
As far as roller rockers i was told i cannot use rolloer rockers on my heads because of the setup? Or are the LT4 roller rockers made for it? this is just what i was told.
As far as exhaust I have Hooker Super Comp headers, w/ staright pipe and Borla Mufflers.
[Modified by MonteSS, 5:14 PM 10/15/2002]
As far as roller rockers i was told i cannot use rolloer rockers on my heads because of the setup? Or are the LT4 roller rockers made for it? this is just what i was told.
As far as exhaust I have Hooker Super Comp headers, w/ staright pipe and Borla Mufflers.
[Modified by MonteSS, 5:14 PM 10/15/2002]
Burning Brakes
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From: Manhattan
Re: 350h.p. LT1????????? (MonteSS)
i don't know about the roller rockers, as everyone on C4 tech has the aluminum heads :(
the exhaust sounds good
what size injectors are you useing? i'd think 22lb or 24lb would be fine
the exhaust sounds good
what size injectors are you useing? i'd think 22lb or 24lb would be fine
Burning Brakes
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From: Manhattan
Re: 350h.p. LT1????????? (MonteSS)
i don't see why you couldn't use roller rockers, they're the same for just about every v8 head chevy made. however crane has different part numbers for valve springs and retainers, which would exclude you from using the hotcam kit. the valve springs are weak in that kit anyway.
you will need to modify the valve covers to fit the roller rockers, at least you need to on the aluminum covers. all you have to do is grind off the drip tabs.
if i remember correctly, most LT1 guys are purchasing the Ford Motorsport 24lb injectors. the word is they're rated 24lb at a lower pressure than stock corvette.
there are a lot of forum members running the hot cam in their LT1's, with ported heads they usually make about 415 crank hp in 6-speed cars.
you will need to modify the valve covers to fit the roller rockers, at least you need to on the aluminum covers. all you have to do is grind off the drip tabs.
if i remember correctly, most LT1 guys are purchasing the Ford Motorsport 24lb injectors. the word is they're rated 24lb at a lower pressure than stock corvette.
there are a lot of forum members running the hot cam in their LT1's, with ported heads they usually make about 415 crank hp in 6-speed cars.
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From: Mass.
Re: 350h.p. LT1????????? (Raistlin)
Thanks. I have a few people looking into stuff, I am also going to meet someone who does quite a bit of engine building and we'll figure out what i need. Like I said most of what I will spending my time is dressup stuff, but while the engine is apart i want to build it. Nothing too crazy. I just wanted to get some opinions from people on this board.
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Re: 350h.p. LT1????????? (MonteSS)
I think the biggest problem will be finding someone who will do the heads for you. I know that we won't CNC iron heads, it's just too hard on the equipment. That leaves you with slow and possibly inconsistent hand porting. They might flow better out of the box, but that doesn't mean they will flow any better once they are ported, just my thoughts on that.
To give you some ideas, look at my setup and decide how much power you want. I did it in stages which is real nice for comparison purposes.
Stock - 269 hp, 300 torque.
LT4 Hot Cam, 1.6 RR's, Springs, Mezierre electric WP, programming, 313.3 hp, 313 torque (completely stock exhaust)
Above + headers, X-pipe, flowmasters, no additional tuning, 336 hp, 345 torque
Above + TEA cylinder heads (CNC ported, hand polished, 2.00 / 1.56 Ferrea undercut stem swirl polished valves, competition valve job, titanium retainers, 10 degree locks) no additional tuning, 365 hp, 348 torque.
Honestly, the single biggest seat of the pants improvement was the headers because of the extra torque they gave. Just the hot cam kit and headers makes quite a bit of power and is worth looking into.
:cheers:
To give you some ideas, look at my setup and decide how much power you want. I did it in stages which is real nice for comparison purposes.
Stock - 269 hp, 300 torque.
LT4 Hot Cam, 1.6 RR's, Springs, Mezierre electric WP, programming, 313.3 hp, 313 torque (completely stock exhaust)
Above + headers, X-pipe, flowmasters, no additional tuning, 336 hp, 345 torque
Above + TEA cylinder heads (CNC ported, hand polished, 2.00 / 1.56 Ferrea undercut stem swirl polished valves, competition valve job, titanium retainers, 10 degree locks) no additional tuning, 365 hp, 348 torque.
Honestly, the single biggest seat of the pants improvement was the headers because of the extra torque they gave. Just the hot cam kit and headers makes quite a bit of power and is worth looking into.
:cheers:
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From: Mass.
Re: 350h.p. LT1????????? (Nathan Plemons)
Thanks I am going to look into the LT4 Cam kit, I will find out more this weekend about the heads. I was just going to have them cleaned up and ported a little, they really don not flow all that bad.
I still dont know I was told you cant use roller rockers on the cast heads, something about the design. Trying to figure out more abou that. Maybe the LT4 package is designed where i can use them????
I am not look for a real power monster I would probably even be happy with 300hp. Dont really want to spend the extra money on heads. For the amount of racing I would do, it would not be worth it for me to do so. Thanks.
I still dont know I was told you cant use roller rockers on the cast heads, something about the design. Trying to figure out more abou that. Maybe the LT4 package is designed where i can use them????
I am not look for a real power monster I would probably even be happy with 300hp. Dont really want to spend the extra money on heads. For the amount of racing I would do, it would not be worth it for me to do so. Thanks.
