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Discussion Starter #1
No there was not a break in at CIC so breathe easy. :thud:

I have been meaning to start this thread for quite some time, I have just had writers block every time I sit down to do it. Well now I have no choice as the build is finally starting to take off. This introduction may get alittle windy.....

Oliver (owner) about 4.5 years ago was looking to do an LS conversion on his 1981 Corvette. His searching led him to the Mistress build I was doing at the time. He inquired if I would help him gather the parts he needed to do the conversion. The challenge to this whole thing was that Oliver is from Germany. :cheers:
So I was going to have to put everything in a crate. It just so happened that I (having not even finished the build) was starting to part out the Mistress because I was going bigger and badder. So I ended up selling him the LS3 Stroker engine I had built, my T56 trans and my 4.11 geared rear end. Then I started collecting the necessary small parts he would need and I ordered some custom parts he wanted too. After all the parts were collected, I was getting everything ready to go in the crate. During the process of collecting everything I started Custom Image Corvettes and I started producing my fender flares. Naturally Oliver being a fan of the Mistress wanted flares for his car. He was also telling me about his Mechanic and getting some information about the swap that he could give to him. His mechanic was very good but he didn't have any experience with the LS engines and he worked out of his garage so there was a window in which he could do the install because he didn't have a heated garage. This is the point where my light bulb went on :smack and I suggested that he could maybe send his car over here and I could do the engine conversion and flare job. That option turned out to not be very feasible. However.....I had a donor car that I had parted out that I was selling (some of you may remember James '82 I had done an LS conversion on) and it was a perfect candidate because it was just a frame and bare body minus a front clip. So he said if he could sell his car that this option could work. Well a few months later his car sold. And that was the beginning of the build at CIC. At that point the build stalled for awhile because I was still setting up CIC and I was trying to complete the work I already had at the shop. I fit in little parts of the project as I could. I got the car stripped and blasted, got the frame blasted and then proceeded to seam weld the entire frame.

Well finally after many delays and numerous design changes we are ready to put this build into overdrive. Mistress is the inspiration for the project but we have some pretty cool and innovative ideas that will be unique to INTRUDER. So stay tuned!

With that being said I turn it over to Oliver to fill in the blanks and to add his perspective and alittle history.

511 Posts
Hi all. Glad to find this build-thread opened today, so i want to give the Vette-fellows here at DC alittle introduction how it came i am part of this thing.
I turned to Corvette in 1990 when purchasing a white 4-speed `81 that just came across the pond all the way from California to my place.
For a year or two i drove her around as she was, just did some necessary restaurations like dashboard / interior overhaul (California sun did her job on it...), transmission rebuild and
some minor repairs that didn`t keep me off the road too long - as this was my only transportation at that time and it had to serve as my DD.

You may know how it feels when your body got adapted to an existing engine power level (good yawn), so in `93 it was time to add some ponies and excitement.
A performance shop also active in Racing business took care of this and built an extremely cammed (solid lifters) four bolt SB with forged internals.

Almost stock from the outside, only big duals with barely muffled Flowmaster Delta`s out back told there is something going on underneath the hood.
Quite nasty !

In the following that motor based on the same shortblock received some cam changes, ported Dart heads, various carbs and so on.

It never turned out to be reliable, as Valvetrain failure hurt me all the way, what for one time even led to a catastrophic failure.

Without motor in the Vette, i decided i no longer want to live with the downsides of a carbed high-rev Small Block (for instance the maximum of 9mpg that i got out of it), so with my research
in Dec `09 i ran into DC, the build of that car named Mistress with an OP that answered all my questions, and this is how my "Engine Swap" :laughing: began ...

As Josh already mentioned above, in the following the parts list grew and at some point it made the most sense to start up from the ground.
So i had to let the white Shark go...

New owner and his son pick up the 81

I don`t know if you once had sentimental feelings towards a car, but after having her twentyone years in the garage, this is like you abandon a dog out in the desert

up and away - here she goes

When looking at some project cars or bikes sometimes is hard to believe where all the time a build can consume goes, but i found out there is advantage to this too.
Sometimes you spot a new part on the market that wasn`t there when you started, or new ideas grow.
During the time of the build we have been changing this and that, different flares, brakes, intake, steering, transmission and what else.
But we must watch out not taking all the changes too far out, or some day in the future i have to get a pilot`s or boatmasters licence because we even changed the type of vehicle built around that LS-motor ! :laughing:

Although using LS power and trying to improve driving quality, i am not going for a modern look restomod.
What is in my mind is a car that - when looked at first glance - is closer to a Custom Car that could have been modified at it`s actual era, than showing the newest tech developments at first sight.
For instance, modern C4-and up wheel-design is not in my book, or - just as example - i would rather prefer a C2 dashboard with advanced but still analog-design gauges versus a carbonized 80`s dash with digital read-outs.

Then again, 82`s with chrome bumpers actually are not really "era-correct"...
For some reason at that time owners rather sorted out the chrome bumperettes on their 68`s and threw the 80-style bumpers on it, as the other way round.
But, it could have been done, so that is what i mean.

In 1982 and the following decade, bigger diameter wheels already were available on other sportscars and the aftermarket, so that option works for me.

I love the design of the ARE-Salt Flat Special wheels or similar Moon rims, and we found some sweet CNC-machined two-piece rims that match that style and allow us to run some better tires.

On the to do list is a clean engine compartment with hidden coils and a top-mouth aluminium spider, but EFI is word so i am not going to step back to carb just to have a complete Vintage look.

Chevy Power Book and a stock frame still works for me, so this is what goes into the frame regarding gussets and full-seam welding.

For suspension - there is a coil-over kit which is being used by a lot of street and track racers still today, this one has already been on the market when the C3 series was actual production.

I have to say that i earlier have never been a lover of the chrome, and even sorted out the tiniest chromed part on my bike.
The rubber-bumper design was on my 81 that i had for such a long time and i always liked the batmobil look at these days.
But as time goes by you may want something different after the years, and today the steel bumper Vettes attract me much more than they did before.

But the final ignition that led me that other direction was that phantom car named Mistress, and the teaser pictures Josh supplied during his build....

like that one :

No i wasn`t ever planing on a stroker engine.
Going stock LS is such a good way to save fuel and still have a powerful motor with plenty of ponies "enough" for any street driven Shark.
But wait until you find a partner for your engine conversion, that keeps telling you how much even more fun he has with his bigger cube mill.....:smack
and so that Mistress Machine caught my interest....:


Premium Member
1,777 Posts

It's great you have a vision, from your and Josh's description I can almost see it rolling down the road. You did well picking CIC to do the work.

There is always scope creep, (improvements) but it looks like you got bitten by the flair bug early. So all the major changes are already planned or done.

I will be following the build, some pretty cool stuff comes out of Josh's shop. You never know, scope creep may impact my build if I see something I cannot live without.

Great stuff, looking forward to updates.

511 Posts
@ 7 T ....
yeah the scope creep lightning strikes us from time to time, let us know if he gets you !
I will for sure, if it happens again.
Glad you are following up and already looking forward on your opinions.

@ Sly ....

me too !!

@ Infiltrator ....
That is the goal !
There it happened, Scope Creep Lightning stroke me again when i saw your transmission in that other thread....

I have spotted his transmission in here on DC, it was sitting around since purchase, due to an unfinished project.

Originally i was lucky to get a used F-Body T-56 from Josh, which was safe, as he has already tried it before, so we knew it is good.
It was stock with some miles on it and for the price i thought if something ever happens it is worth to rebuild.

But i was also thinking that the older standard six-speed might not offer the life span as a rebuilt brandnew rebuilt unit.
So i had an eye on the GTO-box from Jon aka Infiltrator.

A big thank you again to Josh for the Five Star Service and for giving me the opportunity to jump on that other offer and taking back the trans after all that time i already owned it.

The new Heavy Duty Trans is a rebuilt GTO unit in a F-Body housing.
One big advantage of the `05/`06 GTO-internals are the synchros, as the GTO-guts make it possible to take advantage of the triple-/ double-cone blocking ring design.
The GTO`s, CTSV and new model Vettes have that triple synchro rings, what provides smoother engagement of gears, especially when downshifting and at mid / higher revs.

Other than that the upgrades are solid keys for 1-6, bronze fork pads 1-6 & reverse, steel 3-4 shift fork, carbon blockers etc.

It has a (hardened) 27-spline shaft, as according to the builder a 30-spline output shaft is overkill for the power range, and useless spent monies as long as i don`t abuse her on race or drag course.

The box has been built by RKT Performance ( and is designed for the same power range as my motor, because it is about the same as Jon`s plans on the engine have been for his project.

As this wouldn`t be enough, luckily Jon also opted for the same gearing that i always wanted, the MM-6 gearset with 2.66 first and 0.50 sixth.

This should work fine along with the 4.11 rear gears.
A match made in heaven, as Josh is saying.


1,301 Posts
You have my attention, sounds like a really cool build.
What is the stage of the project as of now, any photos?


531 Posts
Hey Oliver, Lets get one thing straight. Thats not the trans I sold you!!!!

its this one!!!! I just need my dremel bit to cut off the ls parts. :cheers::buhbye:

1,517 Posts
Well you know I am subscribed!
Oliver: glad to see your dream car is finally coming to be. I know you have been waiting a long time but it will be so worth it when it is done. I hope I can "buzz over" to South Dakota and see it before it leaves. Should be pretty damn sweet when done.
Funny how I also came across josh on the internet when I was looking into ls swaps. I saw the same view of the mistress mocked up and was bitten. The only difference is I rode my bicycle around the corner and saw her in his garage. :laughing:
I like the ideas you have for the car and can't wait to see the CIC boys make it happen. :thumbsup:

1,441 Posts
Another great build, keep us updated often, looking foward to this one for sure.


511 Posts
Engine Specs / Cam Details

For the ones who like to check out engine numbers :

ENGINE TYPE............ LS 3
DISPLACEMENT........... 416 c.i.
BORE & STROKE........... 4.068 / 4.000
Deck Height :........... stock
Compression.......... 11.3 : 1
Piston Type.......... Forged Flat Top w Valve Reliefs
Rod Length.......... 6.125
Rod Type.......... Forged H-Beam

GM.......... L-92.......... custom ported...........

Valve Sizes :
Intake...... 2.16----- Exhaust..... 1.59

Combustion Chamber Size.......... 68.4

Valve Spring Pressures :

.......... Closed : [email protected]"
.......... Open : [email protected]"
.......... Rate : .660

Rocker Arm Ratio :.......... 1.7

FORGED CRANK......Callies Compstar
FORGED RODS........Callies Compstar

Piston Rings..........Akerly and Childs
Patriot Extreme Dual Springs .660 w. titanium retainers
Clevite H Bearings
ARP main studs and rod bolts

LS 2 timing chain
LS 7 oil pump
MLS gaskets
LS 7 lifters
60 lb injectors
billet pulleys
underdrive balancer


ED CURTIS.....custom Cam.......(Flowtech induction . com)

LSx.........HR 14+2*~~

Lobe Lift :..................................361".............361"
Gross Valve Lift 1.70 Ratio :..........614".............614"
Duration @ .050" Tappet Lift :.......236".............242"

Lobe Separation :
Recommended Intake:::::::::::::::::114*

Specs at 112 Degree Intake Centerline :
Valve Timing at........................Open.................Close
.050" Tappet Lift:..............Intake: 6* BTDC.........50*ABDC
......................................Exhaust: 57*BBDC.......5*ATDC


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Discussion Starter #19
Here is a better video. I saw the flames coming out of the exhaust so I checked the temp of the header primaries and one whole side was cold. So we checked the injectors and they were good and they were firing. Plugs were new. Checked for spark and it had it. But I still had a hunch so I grabbed a spare set of coils and plugged those in and bam! we were in business. Just goes to show how well designed the LS motor is. In the first video we were down 4 cylinders and the car ran smooth except for alittle backfiring.
Now she is running on all 8 cylinders...

932 Posts
Here is a better video. I saw the flames coming out of the exhaust so I checked the temp of the header primaries and one whole side was cold. So we checked the injectors and they were good and they were firing. Plugs were new. Checked for spark and it had it. But I still had a hunch so I grabbed a spare set of coils and plugged those in and bam! we were in business. Just goes to show how well designed the LS motor is. In the first video we were down 4 cylinders and the car ran smooth except for alittle backfiring.
Now she is running on all 8 cylinders...
Man that sounds sweet! :partyon:
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