Hey guys i sold my 1990 camaro and this week were getting all the paper work token care of. Well I know the corvette that i will be getting it is a 1986. It has the 4+3 trans and it also has the Z51 handeling. The guy also said it has the dana 40 rear end? That should be alot stronger than my old 10 bolt?

Well ill throw out some of my ideas and tell me what you think?

1 full exhaust w/ longtube headers (are longtubes hard to do in a C4?)
2 3:73 posi
3 I have a cam that i was going to use on a LT1 project for my camaro. It is a loyde elliot .540/.540 lift. Then i also have spring from loyde elliot.
4 intake i am lost Should i try and port it real big or just go with something different. If so how much am i looking at?
5 Have it all dyno tuned
6 cold air intake

Dont know if that will get me their but i would hope it will get me into the 12's.

thanks
kevin

 

congrats on the C4 purchase. i myself had numerous 3rdgens before i got my first C4... trust me, youll never look back

its a Dana 44 btw, and yes, its MUCH stronger than the fbody 10bolt. its a 8.5" ring and pinion, and theres alot of manual trans guys in the 11s and even 10s with this rear

theres alot of options for intake manifold choices for a TPI car... each person has their own opinion about what is best. i personally would retain the TPI and siamese the base manifold to increase the top end power

i had an 89' automatic with the 3.07 gears and the only mods were a stall, MAD front ypipe, catback, DRs, and some free and cheap mods (AFPR, K&N w cut lid, bumped tiiming, etc) and the car went 13.2 at 104mph. with your planned combo, 12s should be easy. low 12s, though, im not so sure

you didnt mention any head work... any cam upgrade should be at least complimented by some porting. the lift is a little on the high side for stock TPI heads which leads me to believe the intake and exhaust duration #s are probably too large as well. what are the complete specs? also, youre going to NEED some kind of sticky tire to turn the # youre looking for... DRs are good, but for a stick car with instant shock to the driveline, slicks would be best

one thing i cant stress enough with a manual trans at the dragstrip is PRACTICE PRACTICE PRACTICE!!! no one ever runs well their first time out with a stick, even if you can drive well in daily driving. its totally different at the track. most people just go to the strip a few times a year... this is not enough seat time to get the most out of their combos. in my current LT4, it took about 4 - 5 consecutive weekends at the track to get the best #s out of my combo. first trip i only went a best of 12.9 at 113mph. after the 5th visit i had discovered what the car liked and was knocking out 12.2s at 116mph... nothing was changed on the car except the experience of the driver

anyway, refine your combo a little, practice at the strip, and your goal will be met. good luck and enjoy your new ride!

 

It should be a Dana 44...should be stronger than your previous 10 bolt.....if you are looking for 12's, the first place you need to look is the intake...the L98 configuration has long runners making great torque, but low HP....I run the miniram from TPIS..pricey but in my opinion is the best for high rpm flow...there are other less expensive intakes (not many) but there are others available....the cam will need to be swapped, and IMHO, the heads need to go for an after market, high tech aluminum set (yours may already be aluminum since that was the first year for them). You can port yours but.....IMHO, not worth the time.....the 4+3 manual....never had one, but I hear differerent things about them, none real positive on high HP cars....maybe look for the Keisler 5 speed replacement (they have a kit for the C4)

get your wallet out and have fun

 

Need more info on the cam. As the others have said ditch the intake and get a better set of heads

 

while youre at it why not buy a whole new car..

 

Fixt for ya...

To the OP:
A C4 Vette isn't the first choice for a dragstrip oriented car, at least not a cost-effective one.

This being said, you have the advantage of a Dana 44 being in place already, with the 3.07 gearing, you have a 3 series carrier, making the swap to a 3.75 (only ratio available, not 3.73) easier. With a high-powered engine and a stockshift, parts breakage becomes a factor (and the parts supply is drying up). The IRS also takes time and HP to drive as opposed to a solid axle (from a dragstrip launch perspective).

The 4+3 is a poor choice for a dragstrip oriented transmission, but not because of the strength. It's the poorly designed factory shifter, (notchy and looong throws) with NO aftermarket replacement for it. You might be able to cobble up a shifter from something for a Borg Warner Super T-10 (the "4" part of the 4+3), but kiss your factory console goodbye. Better to convert to an automatic, but that entails some work/expense as well. I swapped to a Turbo 400, but it required a lot of work to make it fit properly.

Engine wise, get under the TPI, and you're dealing with a conventional small block Chevy.. You can either modify the factory TPI intake setup (not my first choice), swap to an aftermarket EFI intake (not cheap), or convert it to carbureted operation (best for all out performance, but takes its toll on fuel economy). Each choice has its pros and cons...

The factory cylinder heads can be modified, but again... at a cost. However, since it's not an LT1 style engine, you've got a lot of choices for aftermarket heads.

There's always nitrous, too...

Best of luck to you...

 

I had an '85 4+3, 3.07D44 with bolt ons (roller rockers, K&N, cut lid, underdrives, hogged out plenum and slightly worked base) and a nice shot of N2O. This car went best of 11.92 and was pretty consistant 11.95 to 12.05.

Nothing gives as much bang for the buck on the slightly modded C4 vettes as N2O.

 

Ok thanks for your help guys. I am just now entering my last year of high school but every dime in the car is mine. The car will most likely never see the track but i would like it to be able to move.

I know already it comes with like 65/70 more hp then my 305tbi hahaha slowwww. But i forget the specs on the cam i will have to find the paper. Then what ever i do i would like it to be done right but also for the least money. I am sure i would be plenty happy with a 12.8 car.

Then the Z51 handeling i read can pull .95 g's thats crazy. I love how the car handels. Can anyone explain to me real quick why it is so good?

thanks again
kevin

 

I had a couple of Dana 44s when I was running the irs and both were set up with 3.73 gears.

 

Your 350 will seem quick to the 305 but C4s are pretty slow by todays standards, even 13s is
Youre looking to drop 2 seconds it will take pretty much new/ugraded everything to get there and will co$t. Think long and hard before you take this on.

 

Just asking what do you guys think it will run stock?

Then if i did a full exhaust system with long tube headers
3:73 gears, cold air intake, and mabey a new MSD iginiton system.

What do you think that would run at the track? mabey low 13's??

cam specs are 232/240 and .540/.540

thanks
kevin

 

My '85 ran 14.2 sec stock. It would run very low 13s on a good night with minor bolt ons and the "off road pipe". The N2O brought it to life.

 

Ok and has anyone ever tryed theses? Or would i need to do alot more than just that?

http://www.summitracing.com/parts/SLE-20002/

thanks
kevin

 

Cam too big for stockish TPI

Read this before you invest in new gears if running TPI style intake
http://forums.corvetteforum.com/c4-t...or-3-73-a.html

Some good reading for new Vette owner
http://forums.corvetteforum.com/c4-t...lar-basis.html

 

Isn't that cam a roller cam? Your 86 will be a flat tappet cam.

 

a stock 86 should be low 14s/high 13s with good driving and track conditions. your TBI was a mid - high 15 sec car. huge difference

tires and boltons should get you low 13s... maybe a high 12 if you nail the launch, every shift, and the DA is excellent

gonna need to tear into the motor or add nitrous to go faster than that

btw, the cam you have is for a roller block... your 86 has a flat tappet cam. theyre not interchangeable

 

What "bolt ons" are going to take a stock 86 into low 13's?

 

Oh boy here comes another " factory freak" story

OP-14s stock, 13s if you do every bolt on/free mod inthe book, thats it. Low 12s you will be spending tons of cash, period. Sell taht cam too, it wont work with what you have.

 

Now i have a LS1 driveshaft that i was going to ues on the camaro but will it work on the corvette? or is the corvettes already aluminum?

Then i will hopefully sell the cam, springs, sway bar kit, wonder bar, and a complete LT1 engine. hopefully get around 1000+.

Then that will help pay for what ever my first mod will be.

I kinda want to beat my buddys WS6 trans am one day hes running 13.01 at i think 110-111?

thanks for your help guys
kevin

 

I own an 86 4+3 Z51. I have a Superram, aluminum heads off a 90, 1.6 roller rockers, headers and dual exhaust, a cut lid, underdrive pulleys, 30 lb inj and a self tune. The short block is stock with 92K on it. It has a 3.07 diff and on street tires my best is 13.38. I'm going through the lights in 3rd. Gears and drag radials would probably get me in the 12s or close to it, my best 60 is only 2.06.
I have a short throw kit for the shifter and have never had a problem with the trans after 50 some passes. Lucky?