need help with lt4 mods
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Joined: Feb 2003
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From: AUGUSTA GA
need help with lt4 mods
i am new to the corvette crowd. i come from the 5.0 crowd where the mods are plentiful and cheap! one thing i have learned that pertains to all vehicles is to listen to someone that has done it before. soooo.. i am asking all lt4 owners what is the best head and cam package available for the money? i know LPE is great but look at the $ it takes! i want to know from fellow forum members if there are any reasoably priced head and cam packages available? if so what can i expect to pay and what hp gains should i expext? also it seems like the lt4 mods are scarce since it is a 1 year engine. PLEASE HELP! :)
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From: Exit 89 GSP,Lakewood,NJ The Land Of Mojo
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Re: need help with lt4 mods (CYLT4)
Have you driven the car to the max yet? You may find that you have plenty on tap.
Most guys will just go with a good catback exhaust and 4.10 gears to start off with.
Most guys will just go with a good catback exhaust and 4.10 gears to start off with.
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From: AUGUSTA GA
Re: need help with lt4 mods (Mr Mojo)
i need 60 to 70 more rear wheel hp to compete with my two brother in laws cars. one has a zr1 the other has a zo6! a complete exhaust with long tubes is probably only 30 hp so i need more!!
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From: DrunkDefender
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Re: need help with lt4 mods (CYLT4)
You'll find that in stock form, down to the paper air filter these cars usually put down 290-300 at the rear wheels. Mine put down 293 with a $70 homemade catback exhaust and a KN filter. You can get to 350 rwhp with the stock heads untouched but thats pretty close to max without having them ported. Longtube headers, custom tune, hotcam, electric water pump should put you there. Your car is also lighter than the ZR1, but unless you do some MAJOR work it wont be as fast from a roll or top end as the ZR1. You can take it in the 1/4 but even the ZO6 is gonna be outmatched by the ZR1 on top.
Frank <Mr Mojo> is right about driving the car to its potential. Alot of LT4 owners have put their cars in the 12s in stock form.
Frank <Mr Mojo> is right about driving the car to its potential. Alot of LT4 owners have put their cars in the 12s in stock form.
Race Director
Joined: Feb 2003
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From: Everyday you must choose between the pain of discipline and the pain of regret. Fredericktown, OH
Re: need help with lt4 mods (CYLT4)
CYLT4,
I am new to the game as well (sold a low 11 second stree/strip Nova) and have been doing a great deal of research. The guys on this forum are great at responding to your questions. About three months ago, I bought an LT-4 CE and am in the process of stepping it up a bit (I have not been to the track yet -live in OH).
The comments made about the 4.10 gears I am hearing more and more and will look into those. Currently, I have the vortext rammer cold air, air foil, and am getting the new exhaust this week. Of course, I have no clue if any of these will help.
From what I understand, most LT-1 bolt-ons also work on the LT-4s. Some of the guys who really have their LT-4s flying have gone to the hot cam and headers. There is a guy with a GS who is running 11s with his LT-4.
Good luck and post any of your success stories.
I am new to the game as well (sold a low 11 second stree/strip Nova) and have been doing a great deal of research. The guys on this forum are great at responding to your questions. About three months ago, I bought an LT-4 CE and am in the process of stepping it up a bit (I have not been to the track yet -live in OH).
The comments made about the 4.10 gears I am hearing more and more and will look into those. Currently, I have the vortext rammer cold air, air foil, and am getting the new exhaust this week. Of course, I have no clue if any of these will help.
From what I understand, most LT-1 bolt-ons also work on the LT-4s. Some of the guys who really have their LT-4s flying have gone to the hot cam and headers. There is a guy with a GS who is running 11s with his LT-4.
Good luck and post any of your success stories.
Team Owner
Joined: Sep 2001
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From: Athens AL
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Re: need help with lt4 mods (rcolling)
If you want to compete with Z06s in the 1/4, youll need at least the LT4 Hotcam kit and full exhaust, plus have your heads ported and the manifold ported. Might need just a little more cam than the hotcam though.
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Le Mans Master
Joined: Jul 1999
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From: Phoenix AZ
Re: need help with lt4 mods (RichS)
Here's a list of my LT4 upgrades...
Crane 109831 Cam 222/230 duration .542/.563 lift w 1.6RR's (got if from More Performance)
Stage 4 ported heads 2.055" intake 1.6" exhaust
Port matched intake manifold
Crower SS 1.6 rockers
TPIS longtube headers
RandomTech metal matrix hi-flow cats
Corsa Cat-back system
TPIS cold-air induction
Meziere HD electric water pump
Arizona Speed/Marine 58mm billet throttle body
4.10 gears
B&M Shifter
I know there's stuff I'm forgetting in there as well...I just got up... Anway, this netted me 382RWHP. Which I think is pretty good considering that the heads are way (220+cc runner volume) too big for a 350ci engine, I had them done for the 383 that I am in the process of building, same for the throttle body...with a set of heads made for a 350 and a smaller throttle body I'm sure you could get 390+ out of it.
Crane 109831 Cam 222/230 duration .542/.563 lift w 1.6RR's (got if from More Performance)
Stage 4 ported heads 2.055" intake 1.6" exhaust
Port matched intake manifold
Crower SS 1.6 rockers
TPIS longtube headers
RandomTech metal matrix hi-flow cats
Corsa Cat-back system
TPIS cold-air induction
Meziere HD electric water pump
Arizona Speed/Marine 58mm billet throttle body
4.10 gears
B&M Shifter
I know there's stuff I'm forgetting in there as well...I just got up... Anway, this netted me 382RWHP. Which I think is pretty good considering that the heads are way (220+cc runner volume) too big for a 350ci engine, I had them done for the 383 that I am in the process of building, same for the throttle body...with a set of heads made for a 350 and a smaller throttle body I'm sure you could get 390+ out of it.
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Joined: Feb 2003
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From: AUGUSTA GA
Re: need help with lt4 mods (Zix)
i appreciate all the input and suggestions! :D it is hard to decide where to begin but i think i am going to start with the exhaust first. the plans are to use the exotic muscle long tube headers that will discharge through a custom made x pipe with high flow catsand a corsa cat back to finish the deal! that should net me around 25 rear wheel hp. :cool:
Instructor
Joined: Feb 2003
Posts: 221
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From: T.Dot ON
Re: need help with lt4 mods (CYLT4)
4.09s, headers / exhaust, mezziere pump, perhaps the breathless intake too. MAybe a set of asp underdrive pulleys (cheap compared to march) too. Id say that would make that baby go. Oh and welcome to the vette world ;) :cheers: :cheers:
[Modified by SHiNoBi LT4, 7:44 AM 3/3/2003]
[Modified by SHiNoBi LT4, 7:44 AM 3/3/2003]
Melting Slicks
Joined: Jan 2000
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From: NW Chicago Suburbs
Re: need help with lt4 mods (CYLT4)
I've got an LT4, see my sig for a list of mods. Next I'm planning on 11" rims in the rear, LT4 HOT cam and Exotic Muscle Long Tube Headers (all in the basement) with some fresh tires. I'm plotting a CNC port job on the my LT4 heads, just have to figure out how to scam $1500 from the wife's house upgrade plans :blueangel:
Eric
Eric
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Joined: Feb 2001
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From: Ham Lake, MN
Re: need help with lt4 mods (CYLT4)
You can see my mods and RWHP results in my sig. I'm still running the stock PCM, but hope to get that reprogrammed by DRM this spring. My car dynoed ~294 RWHP bone stock.
Heads and 4.10 gears are the two other mods I'd like to make on my car. I've got another car project sucking up time and money this year, so these will have to wait until at least summer '04.
Good luck! :cheers:
Heads and 4.10 gears are the two other mods I'd like to make on my car. I've got another car project sucking up time and money this year, so these will have to wait until at least summer '04.
Good luck! :cheers:
Safety Car
Joined: Sep 2000
Posts: 3,524
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From: Hinckley Ohio
Re: need help with lt4 mods (SHiNoBi LT4)
Do not recall anyone using underdrive pullys on LT4. Last time I checked no one (including March) made pullys for an LT4. can you provide any info on underdrive pully for LT4??? Who is asp???
Instructor
Joined: Feb 2003
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From: T.Dot ON
Re: need help with lt4 mods (LT4BUD)
The website is ASPracing.COM its a pulley company. The pulley was way cheaper than the march one i had and the build quality is a million times better. Ive had 2 march pullies go bad on me. March uses a piece of ruber and glues the balancer to the pulley, asp uses a lock ring to keep it secure. The machining is a zillion times better also. Not sure if they make them for the LT1. i cant remember the name but theres another company that definitely makes one for the LT4, its a dampener and has a 10% underdrive. I dont think 10% is worth the big bucks though, unless you have a serious race motor.
Safety Car
Joined: Sep 2000
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From: Hinckley Ohio
Re: need help with lt4 mods (SHiNoBi LT4)
I just checked http://www.aspracing.com and I did not see any pulley listed for LT4. The only mention of LT4 is a footnote (*) to the LT1 pullys stating they would NOT work on LT4. ????
Instructor
Joined: Feb 2003
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From: T.Dot ON
Re: need help with lt4 mods (LT4BUD)
Well heres the deal. Try and find out why the stock dampener is a different size on the LT4. I believe the LT4 one is slightly larger. If im correct this is because the LT4 revss higher and they wanted to dampen the frequencies at higher rpms. My guess is that the reason march and asp doesnt make one is because it probably requires a different belt diameter etc. Try emailing march and asp to see what they say about it. OHH.... The name of the other dampener is ATI, i know they make one for the Lt4. Try searching ATI performance or ATI industries.. etc.. :cheers:
Drifting
Joined: Jun 2000
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Re: need help with lt4 mods (SHiNoBi LT4)
Well heres the deal. Try and find out why the stock dampener is a different size on the LT4. I believe the LT4 one is slightly larger. If im correct this is because the LT4 revss higher and they wanted to dampen the frequencies at higher rpms.
Jeff
Le Mans Master
Joined: Jul 1999
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From: Phoenix AZ
Re: need help with lt4 mods (LT4BUD)
No one makes an underdrive pulley for the LT4, March...ASP...no one. I tried getting one about 8 months ago when I was putting heads/cam on mine. I was told by ASP (I think) that they did make one but because of a large number of failures, resulting in very serious engine damage, they decided to discontinue it, and March flat out said that there wasn't enough market demand for them to spend the money of R&D and productiuon...
Pro
Joined: Feb 2002
Posts: 744
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From: Houston Tx
Re: need help with lt4 mods (CYLT4)
As has been stated , LT4's go a long way with some good bolt ons. I did not dyno my car bone stock but would guess it made about 290-295 rwhp. With the full exhaust in my sig plus a cut lid/K&N my car dynoed 317 rwhp. I am guessing those mods were worth about 25 rwhp. A Hot Cam is worth ~25-30 rwhp on a bone stock LT4 and port matched intake will net another ~5+ rwhp.
LT4 heads are very good stock but even a little work on them will net at least 15+ rwhp on up depending on how much you want to spend. With a more aggressive cam like a CC306 getting over 400 rwhp is not too difficult . I have seen several LT4 heads/cam cars make 415+ rwhp on aggreassive hydrolic roller cams so the potential is there...... :seeya
LT4 heads are very good stock but even a little work on them will net at least 15+ rwhp on up depending on how much you want to spend. With a more aggressive cam like a CC306 getting over 400 rwhp is not too difficult . I have seen several LT4 heads/cam cars make 415+ rwhp on aggreassive hydrolic roller cams so the potential is there...... :seeya