Ls6 C4
Thread Starter
Cruising
Joined: Jul 2004
Posts: 14
Likes: 0
From: Minneapois MN
Ls6 C4
I am a total newbie at all this so forgive me. My dad owned a '68 convertible with a 427 that he sold when I was born, so I feel the need to bring vettes back to the family. I recently read Dave McLellan's book Corvette from the Inside which is excellent. My goal is to get the most power and performance from the least amount of money (say less than 25 grand) and thought that buying a used C4 and transplanting a crate LS6 would be a conceptually simple way to achieve my goal. I am not very tech savvy. Is this possible, is this idiotic? :flag
Melting Slicks
Joined: May 2003
Posts: 3,490
Likes: 68
From: Hewitt NJ
If you're willing to spend $25k then just add $5k more and buy a Z06 and save your self the hassle and aggravation of such a swap. Personally I think such a swap is not worth the trouble especially since the prices of the C5 continues to drop dramatically.
Thread Starter
Cruising
Joined: Jul 2004
Posts: 14
Likes: 0
From: Minneapois MN
I don't want the hardtop on the Z06 and I prefer the bodystyle of the C4. Also, I figured insurance would be cheaper on a C4 than a Z06. I suppose I am wondering if it is a simple proposition - replace engine altogether including exhaust and reprogram electronics, or is it going to mean replacing everything including transaxle etc.
Last edited by cheapspeedy; Jul 16, 2004 at 02:46 PM.
Drifting
Joined: May 2004
Posts: 1,536
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From: Bristol CT
I was just gonna say, if your gonna spend 20k, you can easily achieve an insane amount of power building up the 350 to a 396 or bigger...no need to swap engines.....Just call a few performance shops and tell them what kinda power your looking for and what your willing to spend and how you plan on driving your car.....
Thread Starter
Cruising
Joined: Jul 2004
Posts: 14
Likes: 0
From: Minneapois MN
Originally Posted by LT1Vetteguy78
I was just gonna say, if your gonna spend 20k, you can easily achieve an insane amount of power building up the 350 to a 396 or bigger...no need to swap engines.....Just call a few performance shops and tell them what kinda power your looking for and what your willing to spend and how you plan on driving your car.....
Drifting
Joined: May 2004
Posts: 1,536
Likes: 0
From: Bristol CT
I would thnk for 12-15k you can get that kind of performance with a built engine N/A and blown or just all motor work...You can get a TON of good, different advice on this forum, but i think some common advice is building the motor and doing a rear end swap with a good ratio gear setup.....again it all depends on what you are looking for in the cars performance, do you want top speed, do you want 1/4 speed...do you want roadcourse performance....You could simply geta bolt blower with a 125shot and make 500rwhp on DR's and get 10's in teh 1/4 mile...or you can go all out motor work getting great power and all around reliability
Last edited by LT1Vetteguy78; Jul 16, 2004 at 03:21 PM.
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Drifting
Joined: Jul 1999
Posts: 1,337
Likes: 0
From: Brighton, MI
Forget the swap nightmare. I built my 383 on a relatively low budget and pulled 50 more hp at the wheels than a stock Z06 that was on the same dyno right before me. I'm happy. If you can do the build yourself, you can do a 383 for a few thousand. I can't say exactly how much is in mine because a lot of work and parts were given to me by the previous owner of the car. But I'd guess somewhere around $3k.
Thread Starter
Cruising
Joined: Jul 2004
Posts: 14
Likes: 0
From: Minneapois MN
Thank you for your replies, how much do you think it would cost to get 400-500hp from an LT1 naturally aspirated in a streetable and reliable form? I'm still curious if anyone has a hunch how difficult an LT1/98 to LS1/LS6 swap would be. I plan to use the car during the late spring/summer/early fall and probably for autocross or road courses. I am not really interested in running the 1/4 although I respect what times say about a car's performance.
Last edited by cheapspeedy; Jul 16, 2004 at 04:21 PM.
Le Mans Master
Joined: Jul 1999
Posts: 8,683
Likes: 6
From: Phoenix AZ
There have been a few people that have swapped LSx engines into C4's. It is just an engine swap, you do not need to swap out the drivetrain. This is still one of the options I'm considering too. Yes, I know an 383-396 LT4 will make a lot of power, but a 383 LS6 will mkae A LOT more. And I can build the LS6 out of the car and swap them out when I'm ready rather than pull mine to build it over 1-2 months. Then there's the 427 idea...World Castings I think has a regular 427 small block that'll pretty much bolt right into a C4, and that's a nice 550+ HP engine depending on the cam and heads. I've still got a few months to think about it but it's a tough choice!
Burning Brakes
Joined: Jul 2003
Posts: 868
Likes: 5
I think its a good idea,I love how the LS6 guys are turning out huge numbers but those guys are very technical guys.Also that 25k would run out quickly unless you picked up a really cheap c4.
If I wanted to use up 25k and wanted a stout and impressive c4 I'd look for a nice ZR1 or even a Lt4 car and start the little mods...you'd be in the serious HP quickly.
Jason
If I wanted to use up 25k and wanted a stout and impressive c4 I'd look for a nice ZR1 or even a Lt4 car and start the little mods...you'd be in the serious HP quickly.
Jason
Melting Slicks
Joined: Dec 2001
Posts: 2,049
Likes: 0
From: Texas
On your average LT1, gears, torque converter, and slicks wills end you into the mid-high 12s. That's already in line with your AVERAGE Viper driver. The newer ones are a little trickier, but with a head/cam job you'd be on top of them if not past them. Most Viper drivers can't seem to get a grip on thier car's best performance 
I agree with you 100% on the looks. I'd love a post-90 C4 with an LS1 in it, but for value, it's not worth it in my eyes at all. You could have your C4 twin-turboed for under $25k and then modify the engine and what not and probably keep it in budget. ExoticMuscle told me something in the area of $12k without the engine being modified heavily.
I agree with you 100% on the looks. I'd love a post-90 C4 with an LS1 in it, but for value, it's not worth it in my eyes at all. You could have your C4 twin-turboed for under $25k and then modify the engine and what not and probably keep it in budget. ExoticMuscle told me something in the area of $12k without the engine being modified heavily.
Le Mans Master
Joined: Jul 2000
Posts: 7,633
Likes: 324
From: Greenville SC
Originally Posted by Zix
There have been a few people that have swapped LSx engines into C4's. It is just an engine swap, you do not need to swap out the drivetrain. This is still one of the options I'm considering too. Yes, I know an 383-396 LT4 will make a lot of power, but a 383 LS6 will mkae A LOT more. And I can build the LS6 out of the car and swap them out when I'm ready rather than pull mine to build it over 1-2 months. Then there's the 427 idea...World Castings I think has a regular 427 small block that'll pretty much bolt right into a C4, and that's a nice 550+ HP engine depending on the cam and heads. I've still got a few months to think about it but it's a tough choice!
Le Mans Master
Joined: Jul 1999
Posts: 8,683
Likes: 6
From: Phoenix AZ
The World Casting 427 is not a reverse cool block like the LT1/4. It's a normal SBC like the L98s. But it will bolt into a LT1/4 car pretty easily. Also, you can have reverse-cool heads changed to normal-cooling heads so they'll bolt up to the block. This is something I have been considering because the heads I have on my LT4 are too good to get rid of at this point. So one idea was to have them changed to a normal-flowing head and bolt them to the 427 from World Castings.
Safety Car
Joined: Apr 1999
Posts: 4,623
Likes: 2
From: Ohio
Originally Posted by cheapspeedy
I am a total newbie at all this so forgive me. My dad owned a '68 convertible with a 427 that he sold when I was born, so I feel the need to bring vettes back to the family. I recently read Dave McLellan's book Corvette from the Inside which is excellent. My goal is to get the most power and performance from the least amount of money (say less than 25 grand) and thought that buying a used C4 and transplanting a crate LS6 would be a conceptually simple way to achieve my goal. I am not very tech savvy. Is this possible, is this idiotic? :flag
Last edited by h rocks; Jul 16, 2004 at 10:06 PM.
Melting Slicks
Joined: Oct 2002
Posts: 3,193
Likes: 1
From: Cincinnati Oh
Get a nice C4 (manual IMHO, also the Dana44 in the rear helps) and get yourself a big cubes smallblock (either an aftermarket casting or a 400" stroker), throw on a superram or other torquey intake with solid heads and a roller cam, do some tuning and you're there! Always look around for specs, but you might even have some change left over for a blower to really do the job!
Thread Starter
Cruising
Joined: Jul 2004
Posts: 14
Likes: 0
From: Minneapois MN
Thanks again for the replies, I am trying to take it all in. It seems that the consensus is to modify the current C4 block rather than mess with a Gen III swap. I know that Calloway did the twin-turbo around '90, does anyone know of a tuner or supplier for that kind of modification? (I see "ExoticMuscle" mentioned above.)
Last edited by cheapspeedy; Jul 16, 2004 at 11:41 PM.
Le Mans Master
Joined: Jul 1999
Posts: 8,683
Likes: 6
From: Phoenix AZ
There aren't any current bolt-on twin turbo kits for the C4, you can of course always pay someone to fab one up for you...but I don't even want to guess how much that would be, for a quality job. Exotic Muscle doesn't have a TT kit, I'm at their shop all the time.
If I were you, with a strict 25K budget, I'd get a 92+ 6-speed LT1 car, and either buy a 383 shortblock from someone like Scoggin Dickey like these;
http://www.sdpc2000.com/cart.asp?act...art&catid=1580
And have the heads and intake worked over, or buy some nice AFR LT4 heads and an LT4 intake for a little more flow, then swap the engines out and sell the core...or keep it if you want. You'll probably spend 12-15K on the car, 5K for the 383 short-block 3K for the heads/intake/cam. That leaves anywhere from 2-4K for engine swap if you pay someone to do it and some dyno tuning. If you do the swap yourself, you'd save enough money to throw some nice LT headers on it as well. Something to think about, but you could get 480-500 FWHP from that combo depending on the cam selection and heads.
If I were you, with a strict 25K budget, I'd get a 92+ 6-speed LT1 car, and either buy a 383 shortblock from someone like Scoggin Dickey like these;
http://www.sdpc2000.com/cart.asp?act...art&catid=1580
And have the heads and intake worked over, or buy some nice AFR LT4 heads and an LT4 intake for a little more flow, then swap the engines out and sell the core...or keep it if you want. You'll probably spend 12-15K on the car, 5K for the 383 short-block 3K for the heads/intake/cam. That leaves anywhere from 2-4K for engine swap if you pay someone to do it and some dyno tuning. If you do the swap yourself, you'd save enough money to throw some nice LT headers on it as well. Something to think about, but you could get 480-500 FWHP from that combo depending on the cam selection and heads.