dtw92z28

Hi there, I have a 92 z28 convertible and had some big plans to put a 350 tpi setup hoping to produce around 400hp. I know my tranny will eventually go and I don't really care too much about that but my biggest concern is will the unibody frame handle the torque, or should I just leave my convertible with the slow 305. Any info would help out alot.... thanks

sid rs91

weld in subframe connectors are a must in the verts

BADNBLK

iTrader: (11)

Or any thirdgen for that matter!

dtw92z28

Does anyone produce after market sub frame connectors that you can buy ready to weld in. Or is this something you just have to fab up? And is the subframe aluminum? do you have to tig weld these connectors in?

BlueZee28

iTrader: (30)

subframe is steel

I welded in two sets on mine. I have the Alstons from topdownsolutions and the other set is Spohn.

BADNBLK

iTrader: (11)

Did you take one set off, or you actually have two different sets still welded on there?

Your blue car is about to get the nickname Viagra, for all the stiffness it has!

BlueZee28

iTrader: (30)

No there are currently two sets welded on. One inner set (alston) amd one outer set (spohn). It does handle quite nicely

91 Droptop

Wow, could you post a pic of that set up? I will need to do the same, with the engine and Paxton I am looking at abot 500 HP. I know she is going to twist a bit but that set up sounds like a great counter measure

BlueZee28

iTrader: (30)

I don't have one right now unfortunately. Next time I get it on a lift I'll be sure to take pictures. The Spohn set tucks in behind the existing factory subframe connectors which are right behind the ground effects. The Alston set connects the inner frame rail from front to back, front mounts by the transmission crossmember and the rear mounts by the front bolts for the lower control arms.

86T/A_Ram_Air

at a normal power level with a auto you could probably get away with one set. but LS with a 6 speed I understand bluzee's concern with flex

dtw92z28

I'm looking to build a 350 to put into my convertible and hoping to hit close to 400 hp, will the one set of sphon connectors be enough or should I go with both like the viagra car up there.

91 Droptop

I am planning on following in Blue Z's foot steps, I am looking at about 425 HP from the motor, then I have read differant ratings on the Paxton and could end up with more HP than I originally planned. It has taken me a year to build this thing and get all the gaps right, last thing I will need is for it to twist. My next concern will be to try and fabricate a strut brace (3 point) that will fit around my Stealth Ram.

dtw92z28

Sounds like a good plan to me, rather be more rigid than not enough.... Thanks for all the input fellas, she should be running good soon

abray1

The verts flex much more than t-tops or of course hard tops. I recently stiffened up my suspension with sway bar bushings and shocks etc and cracked my windshield. Who knew that could happen but I promise it can and has. I would like to see the double frame connectors on bluezees car as well. I am building a 400rwhp engine and will desperately need it or go broke buying windshields. The car will slide around like a go-cart now though. It just has the factory 305 and just over 100hp. 0-60 in 3 days.

86T/A_Ram_Air

the Spohn sub-frame conectors are a nice pieces and the UMI pieces are also nice. Either one will get the job done

BlueZee28

iTrader: (30)

Viagra car?

I promise to get a good undercar shot next time I have it on a lift. Heck maybe one saturday in the next few weeks my friend will let me use his lift at work and we can act like we're inspecting the car or something

I also have a 4 point Edelbrock strut tower brace that helps a lot too. I think I have a picture of that at least...

abray1

bluezee who did the wiring on your ls swap. If I didn't have 80% of a 350 built I would attempt an ls swap. The wiring is what has me scratching my head. Will the ls computer control a 4l80e just as easy as a 4l60e? If so I would use a 4l80e and be done with it. I hear those things handle 1000hp and still get great MPG. I have torn up 700r4s.

BlueZee28

iTrader: (30)

Pocket made my harness but he's not making them anymore because he's too busy. There's a number of people and businesses that make them though.

You could use a 4L80E but it requires a lot of hammering out the tunnel due to the size of the transmission, and I think maybe a different cross member but I'm not sure.

Da Spudro

i also have the Alstons and Spohns (based on Bluezee) - but they aren't installed yet due to not trusting any shops locally to weld them in. additionally i'm still trying to decide how i want to have them welded in - suspension loaded or unloaded. seems to be some say one way others say another. unloaded makes sense to me, but i only get one shot to do it right.

i plan on going with a UMI strut tower brace and triangulating it, but differently then BlueZee. read too many problems on other forums where the one point on the firewall pulls the firewall and warps it so the glass either breaks or won't line up properly. so i will attach it differently. more than likely by welding two plates to the firewall welding a support rod between the two and then mounting my triangulation to that so it disperses the stress against the whole firewall. (not sure if that made any sense but i have the idea in my head).

i have additionally strengthening i want to do and will probably have done eventually. this is all a slow process for me, but my goal is the start off with a 400-ish HP LQ9 and eventually put a magna-charger on it and run around 650-ish. i don't like the roll cages that stick out of the top area, so i'm trying to figure out how to "cage" it without it sticking out of the top. i have an idea, but again... down the road along ways.

BlueZee28

iTrader: (30)

I also would like a maggie on mine

Definitely weld them in loaded though.

86T/A_Ram_Air

yeah when the suspension is loaded the chassis is in the right poisition. the last thing you need in to weld in subframe connectors while the chassis is flexing a little...that would be no good. so it a nutshell you need to find a shop with a drive on lift

Da Spudro

yeah i found a guy today that actually explained why it needs to be done loaded. Knowing this information... now it makes sense. Basically the way it was described is simply; your car sits the way it will when it's loaded, if you weld it in with the suspension unloaded then the car has to flex to load again to put the car back into it's naturally resting position. this tension that occurs when you reload the suspension could cause some alignment issue or pop the welds once the body flexes.

91 Droptop

I agree, I will do mine on the drive on lift so it is loaded, would still like a good picture as a reference point when either of you get a chance, thanks again.

abray1

I don't know about the roll cage guys. I guess for safety but for looks especially in a vert I wouldn't have one. I like it open with nothing in the way. To each his own. I do want to try the ls thing with eventually a tvs 2300. An ls7 with lower compression pistons and a magnacharger would be incredible or a lsx 454 with one. Anyone try the c5 vette engine accessories? Are they as easy as the z or ta?

86T/A_Ram_Air

hawks used to make a nice roll bar with a third brake light in it. It has since been discontinued