C4 + LS1 + T-56 = Good times!

[subtlez28]

Now, it occurred to me a couple years ago that some of the modern performance cars (C4s, C5s, C6s, newer F-bodies etc) just don't scare you the way old muscle cars did or do. Largely because of sound deadener and better suspension, you just don't get that: "I'm gonna die" feeling anymore (adrenaline). This project is about going back to basics. No creature comforts. Deleted radio, sound deadening, HVAC, power windows/mirrors and almost anything else that doesn't help it go faster.

I've always liked Corvettes for there well designed chassis, light weight, brakes, etc.. etc.. So, when I realized early C4s were getting cheap, and old/worn enough that I wouldn't mind stripping one down I started seriously shopping.

I have High Speed Auto-crossed (one solo timed lap on an open road course) an 02 Z28. I love the LS1 and T56! But it has some inherent deficiencies, and I just didn't want to diminish its street car status. Time for a purpose built, lighter, better chassis to put an LS1 T56 in.

The car I ended up with was an 84 that already had an LS1 swapped in. I'm told this car was put together around 2001. When I got it though, someone had swapped out a built LS1 for a stock 98 LS1, backed it with a 4L60E, but it was a non running basket case.



The good news was it already had a stand alone harness, C5 accessories (except the balancer...), C5 seats, newer black interior, C5 Z06 rims, Konis, good springs/sway bars, and upgraded brakes.


Again, with my less is more, street legal race car build theme, some of the parts (4L60-E, C5 seats, Z06 wheels) went up for sale and the transformation began. Then it stalled for a while, life got in the way, but I'm back on it again.

I put 17x11s all around, and have mostly disassemble the HVAC, deleted most of the interior, power locks/mirrors, and cut out a lot of unused wiring. I picked up a nice aluminum, laser cut dash w Auto-meters gauges. It definitely works w the street legal race car theme, and allowed me to ditch alot of the interior plastics.

I'm not real proud of these photos, as it is a work in progress. Complete with messy garage and parts piled on the car (don't worry I have the carpets on the roof protecting it). But I thought some of you would get a kick out of it, and I wanted to prove I actually have this project I keep talking about.

I don't know why the previous owner painted the valve covers blue, but they will go gray or black soon.


I'm thinking carpet delete and fabricated door panels. Pretty much all business and flat black inside. I may black out the dash, but it is so pretty...



I also removed the Hooker shorty headers it came with as I intend to go with Melrose Header's long tube headers built for LS1 swapped C4s.

[subtlez28]

Right now, I'm continuing disassembly. I plan to remove the LS1, inspect it, and clean up some engine bay issues (scary fuel and brake lines). I have an under-drive balancer to put on that will work with the C5 accessories. It currently sports an F-body balancer, and the accessories are spaced out from the block (w buts and washers...) to make everything line up.

It is hard to measure things now as it is pretty crowded. I also want to check the position of the engine to see if it offset (front to rear or side to side) appropriately. Because this was an early swap, simple adaptor engine mount brackets were not used. In stead some metal was welded in and C5 stands were used. I'll post op some pics of that when I get the engine out.

Here are some more engine pics:





Gratuitous (subtle) Z28 shot!

[Nessumsar]

That is super cool, I never really liked that body style, but they are growing on me more and more. That should be a really fun car when its done.

[CarlC]

I agree with Jon. Super cool.

I may have missed it, but what oil pan will you be using?

[nullshine]

The back to basics theme is awesome!

Looking forward to see how this turns out.

[subtlez28]

Thanks for the kind words guys!

I'm running an F-body pan.

[bonecrrusher]

Yeah I recognize your Z28 in that last pic from your sig over on ls1tech. You post under the conversion section a lot. haha.

Cars look awesome! What brakes are on the Vette now?

[Bow Tie 67]

Shawn its nice to see your making some progress. I'll have to wait to kick this ones *ss.

[JEFFTATE]

Looks like a cool build !!
That ought to haul the mail.

[Jim Nilsen]

It must be something in the air we breath around this area that makes us want to build basic purpose built cars. Could it be the wind blowing it in from Blackhawk Farms or Road America?

I will be looking for more and hope to see progress as it goes.

[cheapthrillz]

Love it! I hate that you beat me to it though...

I have always like the C4s. They are one of my favorite body styles. Not a huge fan of the black trim pieces from the mid 80's, but that can be fixed. I want an early 90's to do the same exact thing you are doing.

How bout a junkyard turbo setup? Possible? Maybe rear mounted?

Good luck and keep plugging!

PS. Paint it up like this:

[MarkM66]

If someone want's to build a steet/track car, I don't think you could beat a C4 as far as price and performance.

[subtlez28]

Shawn its nice to see your making some progress. I'll have to wait to kick this ones *ss.

Yeah, Matt. Time to step my game up! I was quite impressed by Chain Reaction at Blackhawk Farms! I'm thinking it will take your lunch money with the LS1, but if not... I have LS6 heads... If thats not enough I'll put the L92 in!

Or the turbo idea has crossed my mind as well.

Current brakes are the upgraded J55s (just short of 13" fronts), but I have the most the parts to put C5 brakes up front.

[T_Raven]

Dude just the other day I realized I've never seen an LS1 in a C4 and started looking to see how cheap their going for these days lol.

[subtlez28]

Who wants to see some scary stuff?

This had a complete drive line when I received it (though non-running). The ebay add said it just needs a battery and spark plugs to run... yeah right!
Anyway, I took the trans out a while back and left the drive-shaft hanging. Last night I went to take out the DS and saw this:

No strap on one side!! Had I got it running... I'm pretty sure the LS1 would have snapped this u-joint off and... big problems.

But that is not all. This I knew about, but last night I tore it out:


1st of all, why the external fuel pump when the car comes with an in tank FI pump?

Yes, that is hose clamped, spliced in braided line!
Yes, that is inner-tube wrapped around and hose clamped to the pump.

Not to mention this is mounted just behind the rear end. It was held in with 3 sheet metal screws that were literally finger tight! And the atrocity that was the multi-spliced wiring...

Best part is they cut the factory hard line, so now I'm not sure what I will do. I wish it was in tact as it is nice, safe, and reliable. I may just run a push-lock line all the way up, but the factory stuff would have been my preference. Any idea where I could get a replacement factory line?

I have a Racetronix kit to put in tank. I hope the factory pump and assembly is still in place in the tank.

[subtlez28]

I got to work on the C4 last night and again today. One great thing about C4s... they are easy to pull an engine out of! I was worried about going after it without an extra set of hands, but, no problem.


Getting the LS1 out of the way will allow me to clean up the engine bay some, and more importantly, go through some questionable mods.

The front brake lines are kind of a mess, since I received the car modded, I don't know how they looked stock, but I'm not happy w how they sit.


It also let me get a good look at the sections welded in to run the C5 mounts. They are partially bolted together (along with a weak, and now broken weld). I'm open for input here. Start over? Fix this?


Oh, and lets not forget the fuel lines I am so fond of...



More troubling news on that front... The hot wire for the fuel pump relay (for the external pump covered earlier) was run along the fuel lines! Zip tied nearly 100 times, but still managed to be chafed to bare wire! Am I being nit-picky again, or does running a power wire physically attached to the fuel lines strike others as a bad idea? You can see it in the pic, its the one without the weather pack connections, kinda just dangling there. It ran (past tense, gone now) all the way from the firewall to the tank. Though it changes color and wire type at a crimp slice 1/2 way.

Today was a mix of good progress and heartache. I rolled it outside and pressure washed the grime from the engine compartment.

I noticed some fuel was dripping from the return line (the pressure line is disconnected over the diff-where the external pump was). So when I rolled it back in the garage I put a pan under it as I assumed it was just the fuel in the line (it had been sitting nose up for so long). I even used a big antifreeze pan to be safe... WRONG! Apparently a lot of fuel can siphon from the return line. I smelled gas in the house... ah oh.. Go into the garage to find gas all over the floor.

I did a lot of cleaning up with the hose, but the smell lingers. Luckily most of the area effected was clear, but some boxes and wood blocks got tossed. I wonder how long the smell will last.

Back to good news, Classic Tube sells a complete fuel line. Though I imagine I will have to drop the tank and rear suspension to install it. They also offer brake lines.

HELP WANTED:
Does anyone have pics of a stock 84 engine compartment without an engine? I'm wondering how the factory fuel and brake lines route, and terminate. I'm also curious how the old SBC mounts, and how my cross member has been modded.

[montessaj]

I do not think your being nit-picky about some of the work done to the car. I would be equally irritated. What the heck is up with the FORD blue valve covers? lol You have your work cut out for you my man.

[shudog]

wow, nice project! I really admire your motivation! That fuel pump is scary and the wiring stresses me out just looking at it.

Obviously the C4's don't have the structural rigidity that C5's 6's do. Do you plan on any chassis upgrades to handle the extra power?

[subtlez28]

wow, nice project! I really admire your motivation! That fuel pump is scary and the wiring stresses me out just looking at it.

Obviously the C4's don't have the structural rigidity that C5's 6's do. Do you plan on any chassis upgrades to handle the extra power?

Thanks guys, I'm glad it isn't just me.

As far as rigidity... What do you mean, the 84 has braces all over the place!

But, yeah, I hope to have a cage in it at some point.

[Bow Tie 67]

Shaun to bad you dont smoke that would clear out the fuel smell quick. Lol Let me know if you need my help on that front, and I can light one up.

Ok the brace issue, what the heck was attached to it? It looks weak to me, especially if it is meant to support anything with weight or high loads. ( I looked at it again and I'm thinking these are supposed to support the engine? ) If so this most likely needs to be re-engineered. You may want to join a C4 forum for some pics?