Lt4?
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From: Palos Hills, IL
Lt4? what makes it so different from a LT1
is it the same diplacement...350 ci or is it a 383?
what makes it so much differnt...is it worth the money or is there a better way to make it beat a Supercharged Mustang GT 5-speed (stock suspension)
wahts a badass streetable setup thats Affordable for an LT1
is it the same diplacement...350 ci or is it a 383?
what makes it so much differnt...is it worth the money or is there a better way to make it beat a Supercharged Mustang GT 5-speed (stock suspension)
wahts a badass streetable setup thats Affordable for an LT1
Joined: May 2004
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From: Halfway back on the Highway to Hell...again!
The LT4 had a different set of heads and intake. The ports on each were .100" taller and the runners were just a few cc's bigger. Also, the cam was higher in duration and lift. It put out 330hp (rated). It was known to be more though. In the 96 Grand sport vette, it was known to be 330 RWHP. To beat a s/c'd stang would depend on how much boost he is pushing. For an LT1, your best bet, if you want an LT4 setup is to buy the LT4 Hotcam kit w/ heads and intake. It runs for @ $2300. If you want just the cam kit, I got mine from Summit for $496 and it comes with cam, springs, spring pads, retainers, keepers, and the GM aluminum roller rockers. *NOTE, programming is a must, LT4 knock module is a very good idea, and composite valve covers help reduce roller rocker noise. If you just run the cam, it won't perform to it's upmost with out a set of good flowing heads, AFR or TEA(Total Engine Airflow). I personally think TEA is the best worked. Hot cam motors have been known to push 475-500hp n/a, streetable.
The differences between the LT4 and LT1engines:
54cc Combustion Chambers vs 58 cc for the LT1.
LT4 pistons have shallower valve pockets than the LT1. This along with the smaller combustion chamber design gave the LT4 10.8/1 CR vs 10.5/1 CR for the LT1
Larger 195 cc intake runner volume vs 170 cc intake runner volume for the LT1
LT4 heads have larger stainless steel sodium filled valves (2.00" intake, 1.55" exhaust) vs LT1 steel valves (1.94" intake, 1.50" exhaust)
The specs on the cam are similar to the LT4 and the LT1, but the LT4 used 1.6/1 roller rockers vs 1.5/1 ball fulcrum rockers on the LT1. (203/210 duration 0.476/0.479 lift, 115 LSA vs 200/207 duration 0.447/0.459 lift w 1.5/1rockers, 117 LSA for the LT1)
New chamfered top compression ring to prevent excess blowby due to increased compression
LT4 uses 28 lb/hr injectors vs 22 or 24 lb/hr injectors on the LT1
LT4 has steel roller timing chain vs LT1's powdered metal butt link timing chain
LT4 undercut and rolled crank journals
Though rated at 330 FWHP, most would agree that these engines were underated ( chassis dyno test on LT4 Vettes, and Special edition F-body LT4s are routinely 290-300 RWHP).
54cc Combustion Chambers vs 58 cc for the LT1.
LT4 pistons have shallower valve pockets than the LT1. This along with the smaller combustion chamber design gave the LT4 10.8/1 CR vs 10.5/1 CR for the LT1
Larger 195 cc intake runner volume vs 170 cc intake runner volume for the LT1
LT4 heads have larger stainless steel sodium filled valves (2.00" intake, 1.55" exhaust) vs LT1 steel valves (1.94" intake, 1.50" exhaust)
The specs on the cam are similar to the LT4 and the LT1, but the LT4 used 1.6/1 roller rockers vs 1.5/1 ball fulcrum rockers on the LT1. (203/210 duration 0.476/0.479 lift, 115 LSA vs 200/207 duration 0.447/0.459 lift w 1.5/1rockers, 117 LSA for the LT1)
New chamfered top compression ring to prevent excess blowby due to increased compression
LT4 uses 28 lb/hr injectors vs 22 or 24 lb/hr injectors on the LT1
LT4 has steel roller timing chain vs LT1's powdered metal butt link timing chain
LT4 undercut and rolled crank journals
Though rated at 330 FWHP, most would agree that these engines were underated ( chassis dyno test on LT4 Vettes, and Special edition F-body LT4s are routinely 290-300 RWHP).
On The Tree
Joined: Dec 2001
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Originally Posted by METALBEAST
The differences between the LT4 and LT1engines:
54cc Combustion Chambers vs 58 cc for the LT1.
LT4 pistons have shallower valve pockets than the LT1. This along with the smaller combustion chamber design gave the LT4 10.8/1 CR vs 10.5/1 CR for the LT1
Larger 195 cc intake runner volume vs 170 cc intake runner volume for the LT1
LT4 heads have larger stainless steel sodium filled valves (2.00" intake, 1.55" exhaust) vs LT1 steel valves (1.94" intake, 1.50" exhaust)
The specs on the cam are similar to the LT4 and the LT1, but the LT4 used 1.6/1 roller rockers vs 1.5/1 ball fulcrum rockers on the LT1. (203/210 duration 0.476/0.479 lift, 115 LSA vs 200/207 duration 0.447/0.459 lift w 1.5/1rockers, 117 LSA for the LT1)
New chamfered top compression ring to prevent excess blowby due to increased compression
LT4 uses 28 lb/hr injectors vs 22 or 24 lb/hr injectors on the LT1
LT4 has steel roller timing chain vs LT1's powdered metal butt link timing chain
LT4 undercut and rolled crank journals
Though rated at 330 FWHP, most would agree that these engines were underated ( chassis dyno test on LT4 Vettes, and Special edition F-body LT4s are routinely 290-300 RWHP).
54cc Combustion Chambers vs 58 cc for the LT1.
LT4 pistons have shallower valve pockets than the LT1. This along with the smaller combustion chamber design gave the LT4 10.8/1 CR vs 10.5/1 CR for the LT1
Larger 195 cc intake runner volume vs 170 cc intake runner volume for the LT1
LT4 heads have larger stainless steel sodium filled valves (2.00" intake, 1.55" exhaust) vs LT1 steel valves (1.94" intake, 1.50" exhaust)
The specs on the cam are similar to the LT4 and the LT1, but the LT4 used 1.6/1 roller rockers vs 1.5/1 ball fulcrum rockers on the LT1. (203/210 duration 0.476/0.479 lift, 115 LSA vs 200/207 duration 0.447/0.459 lift w 1.5/1rockers, 117 LSA for the LT1)
New chamfered top compression ring to prevent excess blowby due to increased compression
LT4 uses 28 lb/hr injectors vs 22 or 24 lb/hr injectors on the LT1
LT4 has steel roller timing chain vs LT1's powdered metal butt link timing chain
LT4 undercut and rolled crank journals
Though rated at 330 FWHP, most would agree that these engines were underated ( chassis dyno test on LT4 Vettes, and Special edition F-body LT4s are routinely 290-300 RWHP).
Originally Posted by Steve in Seattle
I've heard higher than 300rwhp... I mean damn... my stock 97 with only a CAI made 280. The big LT4 gains were in the heads (higher cfm & lighter valves for higher redline).
i thought the LT4 had these specs...218/228 .525/.525 112
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Verdad Gallardo Joined: May 2004
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From: Halfway back on the Highway to Hell...again!
WS6BIRD, Well i gave you the basics and Metalbeast went all out. This should pretty much do it for ya, eh? I have the hotcam in my Imp and it rocks, but if I were to do it again, the CC306 with the Magnum roller rockers would go in. I'm just not that financially set.
On The Tree
Joined: Nov 2003
Posts: 189
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From: South Jersey
Originally Posted by 02WS6Bird
whats a badass streetable setup thats Affordable for an LT1
You could push 400 RWHP easily with a cam and matched heads in an lt1 for about 2k. Converting to lt4 is not worth it unless you go all out with ported lt4 castings which will cost you $1200 for the castings then an additional 1-2k for the headwork.
Rich
Metalbeast..heres some backup for you. 
Dyno results with mods listed...very very similar to the LS1 ..though I believe it makes more torque.
http://www.grandsportregistry.com/dyno.htm
Dyno results with mods listed...very very similar to the LS1 ..though I believe it makes more torque.http://www.grandsportregistry.com/dyno.htm
bone stock i put down 272hp and 309tq to the wheels. thats with 70k on the odo and through a manual. i am a WS6 though. around 300 at the wheels is what ive seen LT4 vettes dyno. the fbodies are capable of much more. those engines where worked from SLP. the computers where not changed enough to accomodate the LT4. this was done because those cars would have to be recertivied for emissions. so they got around that, but not tunning it correctly. its not unheard of for LT4 fbodies to put down 330+ after being tuned for what they actually are, but there were only 129 built.
Launching!
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From: HighDesert California
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From: Palos Hills, IL
http://store.summitracing.com/partde...3287-1&Ntt=LT4 Hotcam&Ntk=KeywordSearch&N=110&PartSearchFlag=
is that the LT4 hotcam included in the package and is it true 425 hp?....or is that jsut am regular LT4 cam...that loks like cam heads valvetrain and intake would it be better to get different heads or something if that is the LT4 HOTCAM
is that the LT4 hotcam included in the package and is it true 425 hp?....or is that jsut am regular LT4 cam...that loks like cam heads valvetrain and intake would it be better to get different heads or something if that is the LT4 HOTCAM
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From: Palos Hills, IL
anybody kno bout that^ if you clikc the link clikc on the LT4 conversion....otherwise just copy and paste it into the URL...
it claims....LT4 Intake, Heads, and Hotcam with 1.6 rockers and whatever the hell else there is...it says 425 proven horsepower....so theya re really tlaking bout the LT4 hotcam?....or just the normal LT4 cam?
it claims....LT4 Intake, Heads, and Hotcam with 1.6 rockers and whatever the hell else there is...it says 425 proven horsepower....so theya re really tlaking bout the LT4 hotcam?....or just the normal LT4 cam?
Originally Posted by 02WS6Bird
wahts a badass streetable setup thats Affordable for an LT1
LT4 UPGRADE KIT W/HOT CAM $2,139.95
LT4 UPGRADE KIT W/LT4 PRODUCTION CAM $2,189.95
Teching In
Joined: Aug 2004
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From: TEXAS
We try to keep the the LT-1 to LT-4 conversion kits in stock. It is avaliable with the LT-4 production or LT4 HOT CAM. For the ultimate "ponykiller" we also offer CNC ported LT-4 heads. For the guys that want to stick with the LT-1 heads we have a couple of great buys. CNC LT-1 heads with the LT-4 springs for $647.50 and With CC987 Springs for $750.00. There a limited quanities of the LT-1 heads so be quick. Mention this post and I will cover up to $50 of shipping cost on lt-1 CNC'd heads. 