Newbie C4 Owner
Discussion
Hi all,
first post on here and I thought I'd put it in the Corvette section.
I'm 23 and live and work in Dorset in the South-West.
Here's some info on my car:
The car handles very well and is capable of keeping up with most things even on the twistys. Next attention has to go to the brakes. The fluid especially. I managed to blow the lid off of the resivor on a sprinted drive!
5.7l V8 TPI Gen1 Chevy Small Block
10.6:1 Compression,
Stock Forged Pistions,
Uprated Aluminum heads,
Fel:Pro Gaskets,
262/272 Flat Tappet Camshaft,
'7730 MAP ECM - Self Tuned,
Fully De-Catted and "Straight Through" Exhaust
Removed AIR and EGR (Emissions)
Rebuilt '91 TH700r4 Auto Transmisson built with Alto Frictions,
1,800 RPM Torque Converter.
I've had my 1985 C4 for just over a year now, in which time I've had to freshen up the engine and completely re-build the Automatic Gearbox.
So far the I've managed to get a 14.01@99mph 1/4 mile out of it. The top end was really being strangled and found the autobox wanting to rev higher than the engine was making power.
The only track action I managed to get this year was "Trax" at Silverstone. I had a wicked day and loved my session. I definately want to do some more tracks next year.
It's off the road at the moment having an LT1 Intake Manifold Conversion. Getting rid of the TPI should really awaken the top end power!
A NOS Nitrous kit is being fitted at the same time but I won't be using that untill the summer of next year. I'm really looking forward to this bit!
first post on here and I thought I'd put it in the Corvette section.
I'm 23 and live and work in Dorset in the South-West.
Here's some info on my car:
The car handles very well and is capable of keeping up with most things even on the twistys. Next attention has to go to the brakes. The fluid especially. I managed to blow the lid off of the resivor on a sprinted drive!
5.7l V8 TPI Gen1 Chevy Small Block
10.6:1 Compression,
Stock Forged Pistions,
Uprated Aluminum heads,
Fel:Pro Gaskets,
262/272 Flat Tappet Camshaft,
'7730 MAP ECM - Self Tuned,
Fully De-Catted and "Straight Through" Exhaust
Removed AIR and EGR (Emissions)
Rebuilt '91 TH700r4 Auto Transmisson built with Alto Frictions,
1,800 RPM Torque Converter.
I've had my 1985 C4 for just over a year now, in which time I've had to freshen up the engine and completely re-build the Automatic Gearbox.
So far the I've managed to get a 14.01@99mph 1/4 mile out of it. The top end was really being strangled and found the autobox wanting to rev higher than the engine was making power.
The only track action I managed to get this year was "Trax" at Silverstone. I had a wicked day and loved my session. I definately want to do some more tracks next year.
It's off the road at the moment having an LT1 Intake Manifold Conversion. Getting rid of the TPI should really awaken the top end power!
A NOS Nitrous kit is being fitted at the same time but I won't be using that untill the summer of next year. I'm really looking forward to this bit!
Welcome dan,there are a few C4 owners on this forum including myself,Fran should be a long soon and is an owner that likes to put his car through its paces.
C5Ragtop is down Dorset way and is the area rep for that area.
Is the shop where your car is photo'd in between Poole and Bournemouth?
C5Ragtop is down Dorset way and is the area rep for that area.
Is the shop where your car is photo'd in between Poole and Bournemouth?
Hello Dan - seen you on CCCUK! Think I asked you about your car then too.
Given my car some grief over the last few years, did Trax in 2002 and fired my '86 off the end of the start finish straight on my first fast lap - great fun can be said since no one was hurt or anything damaged - but a silly way to find the limits (I can safely say my ambition exceeded my ability at the time!)
Good choice for the top end - I'm sure you already know it was reckoned to be mostly the LT1 style intake that created the biggest power difference between Gen 1 and Gen 2 engines.
My car has few mods, running a later engine now ('89) over the stock '86, with dual straight through exhausts (stock manifolds and back boxes though), think the box may have a shift kit on it. My TCC has never operated. When I took her up the 'pod I got E/T's in the 13.9's (think as low as a .92 but would have to fish out the slips) at 99mph. Took on an Mi16 equipped 205 autograss racer - beat him, a single turbo (read late eighties not heavily modded Mark IV) Supra, beat him, and a Vauxhall Viva estate, he thrashed me (think he did a 10 something) - although he was packing 550 hp small block power! Last match was a new Mustang - he only just beat me on ET ( he did a 13.8 from memory), but my reaction times could be measured in weeks!
What technique were you using for the launch - I would expect you to enjoy lower times than mine? Book says 14.3 for a stock C4.
Anyway - hope to meet up with you at some point - we've probably a few L98 stories to swap!!
Ooh - as for brakes - sounds like you've got old fluid in there, or a very very heavy braking foot! I usually lose the pads on mine (read pad fade) - I changed the fluid on mine to DOT 5 a while ago and now don't experience any fluid related problems. It is well known that C4 brakes are marginal at best, although at Trax a friend with a C5 backed off earlier inthe session than I due to brake fade, although to be fair his brakes would have been working harder (he was hitting 130 mph vs my 120 on the straight)
Sorry for the too many words! In China at the moment on a coffee break!
Given my car some grief over the last few years, did Trax in 2002 and fired my '86 off the end of the start finish straight on my first fast lap - great fun can be said since no one was hurt or anything damaged - but a silly way to find the limits (I can safely say my ambition exceeded my ability at the time!)
Good choice for the top end - I'm sure you already know it was reckoned to be mostly the LT1 style intake that created the biggest power difference between Gen 1 and Gen 2 engines.
My car has few mods, running a later engine now ('89) over the stock '86, with dual straight through exhausts (stock manifolds and back boxes though), think the box may have a shift kit on it. My TCC has never operated. When I took her up the 'pod I got E/T's in the 13.9's (think as low as a .92 but would have to fish out the slips) at 99mph. Took on an Mi16 equipped 205 autograss racer - beat him, a single turbo (read late eighties not heavily modded Mark IV) Supra, beat him, and a Vauxhall Viva estate, he thrashed me (think he did a 10 something) - although he was packing 550 hp small block power! Last match was a new Mustang - he only just beat me on ET ( he did a 13.8 from memory), but my reaction times could be measured in weeks!
What technique were you using for the launch - I would expect you to enjoy lower times than mine? Book says 14.3 for a stock C4.
Anyway - hope to meet up with you at some point - we've probably a few L98 stories to swap!!
Ooh - as for brakes - sounds like you've got old fluid in there, or a very very heavy braking foot! I usually lose the pads on mine (read pad fade) - I changed the fluid on mine to DOT 5 a while ago and now don't experience any fluid related problems. It is well known that C4 brakes are marginal at best, although at Trax a friend with a C5 backed off earlier inthe session than I due to brake fade, although to be fair his brakes would have been working harder (he was hitting 130 mph vs my 120 on the straight)
Sorry for the too many words! In China at the moment on a coffee break!
Hiya Fran,
nice to see someone else uses their car as it should be! way to many show and shiners in the corvette scene for my liking!
I've recently put some clean DOT4 in there and that seems to have helped a bit. I will probably flush that through with DOT5 before I do any track work next year.
I hope to be getting LOW 12's with the LT1 and NOS combo. From reading on the US forums it seems that 11's are possible with Drag Radials.
All going well with the LT1 conversion, there should be a supplier in the UK for pre-modified intake manifolds! I will keep you updated with how I get on!
nice to see someone else uses their car as it should be! way to many show and shiners in the corvette scene for my liking!
I've recently put some clean DOT4 in there and that seems to have helped a bit. I will probably flush that through with DOT5 before I do any track work next year.
I hope to be getting LOW 12's with the LT1 and NOS combo. From reading on the US forums it seems that 11's are possible with Drag Radials.
All going well with the LT1 conversion, there should be a supplier in the UK for pre-modified intake manifolds! I will keep you updated with how I get on!
Yep, mines a bit matt these days! Will respray once I've mastered the technique and opened a can of time!
Brakes on C4's - would be great to upgrade but the cost comes in at nearly £2k for the decent Movit items, and with the stock wheels many of the upgrades are limited.
I did some thinking about speccing up an engine when my original let go of a big end, if the 89 engine hadn't of come up I was looking at the TPI MiniRam conversion amongst other bits(is this what you've gone for?) Are you doing the conversion yourself? 400 hp shouldn't be too difficultonce the stock TPI has been swapped. Although I think one of the things to watch is that the TPI set up is a great match for the autobox.
The Vette holds its own up against a lot more machinery than you'd expect on the twisties - it's only slight downside I think is that it doesn't communicate terribly well where the limits are, I guess this is the price paid for a reasonably weighty (but not that lardy in today's climate) car with big rubber on it.
Brakes on C4's - would be great to upgrade but the cost comes in at nearly £2k for the decent Movit items, and with the stock wheels many of the upgrades are limited.
I did some thinking about speccing up an engine when my original let go of a big end, if the 89 engine hadn't of come up I was looking at the TPI MiniRam conversion amongst other bits(is this what you've gone for?) Are you doing the conversion yourself? 400 hp shouldn't be too difficultonce the stock TPI has been swapped. Although I think one of the things to watch is that the TPI set up is a great match for the autobox.
The Vette holds its own up against a lot more machinery than you'd expect on the twisties - it's only slight downside I think is that it doesn't communicate terribly well where the limits are, I guess this is the price paid for a reasonably weighty (but not that lardy in today's climate) car with big rubber on it.
I couldn't justify the price of a MINI-RAM so we're actually doing conversions on standard LT1 Intake manifold. Theres a bit of sorting out to do with regards to coolant and space issues but its been done plenty in the states so theres enough information to go with.
I would guess this will cost around HALF of what a mini-ram would be, and the figures shouldn't be TOO far off.
I find two problems with the Vette's handling, firstly understeer! and secondly its not particularly stable on the brakes!
To combat the understeer at Silverstone I was trailing the brakes into the corner slightly, this was just enough to lighting the rear and help bring the car around. Its a fine point between that and Oversteer though :S
- While its off the road I'm searching the net for stuff to tidy it up, I really can't decide if I should buy some nice seat covers (IGGEE's?) and mats etc or just chuck the whole lot out and replace it with a cage and some buckets? I honestly think the latter would be cheaper but at the cost of comfort.
The paint work is TERRIBLE on mine. I know its going to cost to have it re-sprayed purely because the paint on there at the moment has been layed so thick that its chipping off.
I would guess this will cost around HALF of what a mini-ram would be, and the figures shouldn't be TOO far off.
I find two problems with the Vette's handling, firstly understeer! and secondly its not particularly stable on the brakes!
To combat the understeer at Silverstone I was trailing the brakes into the corner slightly, this was just enough to lighting the rear and help bring the car around. Its a fine point between that and Oversteer though :S
- While its off the road I'm searching the net for stuff to tidy it up, I really can't decide if I should buy some nice seat covers (IGGEE's?) and mats etc or just chuck the whole lot out and replace it with a cage and some buckets? I honestly think the latter would be cheaper but at the cost of comfort.
The paint work is TERRIBLE on mine. I know its going to cost to have it re-sprayed purely because the paint on there at the moment has been layed so thick that its chipping off.
Dan - what suspension does yours have? Mine is stable under braking although warped disks cause quite a bit of vibration (I'd liken the braking exprience to stopping a 747...) - but it stops without stability problems and a hard shove sees them stop the car fairly sharply.
As for understeer, it depends on a few things, mine's got the Z51 option so is pretty responsive, when I did the Ferrari track day (it was with Car Limits at North Weald) to make the most of high speed cornering it was a question of not giving the car light throttle (something I've tended to do for many years to stop the rear end pushing or dragging) leave the box in 3rd and keep your feet away from the pedals. Result - no understeer, in fact the front really bit the tarmac (could feel it working). At the time it was doing a better job of the corner than a couple of Ultimas there!
Other thing to look at is the camber settings at the front (and rear actually) - they're very adjustable on the Corvette, and I've driven different C4's that feel like totally different cars to drive, so setting these up may help.
Keith Beschi's Eurovettes site lists camber settings for stock, fast road and track use, might be worth a go?
Sounds liek you're having a lot of fun with it.
As for understeer, it depends on a few things, mine's got the Z51 option so is pretty responsive, when I did the Ferrari track day (it was with Car Limits at North Weald) to make the most of high speed cornering it was a question of not giving the car light throttle (something I've tended to do for many years to stop the rear end pushing or dragging) leave the box in 3rd and keep your feet away from the pedals. Result - no understeer, in fact the front really bit the tarmac (could feel it working). At the time it was doing a better job of the corner than a couple of Ultimas there!
Other thing to look at is the camber settings at the front (and rear actually) - they're very adjustable on the Corvette, and I've driven different C4's that feel like totally different cars to drive, so setting these up may help.
Keith Beschi's Eurovettes site lists camber settings for stock, fast road and track use, might be worth a go?
Sounds liek you're having a lot of fun with it.
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