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Showing posts from 2012

So - what next?

Update summer 2015
I have been in contact with new owner of the car. The car was sold early 2013 and it is still on the street. No breakdowns or other problems other than minor adjustments. According to owner the car is running very well. And I am very happy to learn about that.

Late 2012
Summer is gone and a new winter just ahead of us. Car and new engine has done about 1000 km (somewhere between 600 and 700 US miles) and engine is pulling stronger than stock 350  LT1 (would have been very disappointing if not).

My plan earlier was to continue to upgrade engine. Ported intake and new 58 mm throttle body, convert PCM to a more modern engine control system, install a heavy duty timing gear and chain (this one requires either to upgrade the optispark to a dowel pin driven opti or change the complete engine control system). The possibilities are "endless" if time and money. But I have got some second thoughts about my plans. Enough is enough.

I'm only driving the car on st…

Final adjustments and closing project

It has been some weeks since last update of my Corvette blog. I have done about 160 km (100 miles) by now since motor was back in car. I have also been two weeks in US on vacation. The final tune and last parts bought took some days to get - so two weeks vacation in US was the right thing to do ;-)
As part of transmission overhaul I also installed an external gear oil cooler which was installed "after" the internal gear oil cooler in radiator. In one of my testruns I blew one of the cooler hoses and sprayed a couple of litres of transmission oil on the street. End of that story was going home by rescue car and dumped the external cooler. Bought another external gear oil cooler with termostat and fan. The new external cooler bypass the internal gear oil cooler. 
After the first start of engine (including a couple of start/stop to get enough transmission fluid into the transmission and checking for any leaks of fluid) I ran the engine in garage for about 20 minutes in 2000 rp…

First real trip with car

Today I picked up the car at the transmission workshop. Last week I had only first gear and reverse gear.  On my first testdrive the transmission just shifted from first gear into neutral when it should shift to second gear. Thew car was transported to the workshop last week, and they dropped the pan of the transmission (TH700R4) and checked whatever they had to check. It was this workshop which fully overhauled and strengthen the transmission - transmission is still under warranty. Anyway - they could not find any obvious reason why transmission would not shift from first to second gear. Put every thing together and out for a testdrive. And now the transmission shifts gear as it is supposed to do. And when problemed was sorted out - my first 30 minutes real ride with car (from transmission workshop and back home). And everything seems to work fine. I might have a to high AFR. I have installed a Innovative Motorsports wideband lambda and it shows a to high AFR. I have some exhaust le…

Engine started

At last and after 6 months of work (mid september 2011), today Friday 4 of May 2012 I started the new engine for first time. And the engine fired at first attempt. Still there are some work to do. More checking, continue breaking in, more checking and so on.. Anyway - engine is running and a major milestone is achieved..

Update 11 May : The engine seems to be running fine. I have some problems with the transmission. The transmission (a TH700R4), which is fully overhauled and strengthen, does not shift to second and third gear. For the moment I have only first and revers. I thought there were som problems with the TV-cable - but it is not. The workshop which did the job on the transmission is local - they will of course fix the problem for me.

I`m also installing Innovative wideband lambda in the Vette (for AFR). I will also do a TTS Datamaster logging on the engine.

Engine installed

Today I commenced installing engine in car. It took me about 12 hours to bolt engine to engine mounts and install and bolt the C-beam. I started to install the C-beam by one bolt onto the differential. After that I used the "elephant" to lift the engine and carefully lowered it in the engine bay.  There are not much space in a C4 engine compartment and I had to remove the serpentine belt to get the engine in place. I supported the transmission by jack when connection the transmission and driveshaft. When engine was standing onto the engine mounts I slided the C-beam into place. During this process I supported the transmission and by end of day all bolts was entered. I will torque the bolts tomorrow.

Update April 20 : Engine and transmission are back in Covette. Exhaust pipes (Melrose Longtube headers and BB-TriFlow 3" exhaust) are installed. Engine is prepared with oil (normal mineral oil for engine break-in process) and transmission fluid. The main remaining now are i…

Engine moved to garage

Engine was assembled in-house (it was not without comments ..). My garage is to cold and to smal for any work on engine, specially during the winter . With only new engine parts assembling engine in-house was no problem regarding any dirt or oil. And it was warm and pleasant sitting in my sofa assembling - I can recommend it ;-) The only worry was how to move the engine out in the garage when due. Today I decided to move it. Couple of hours later and without any assistance - engine is ready for going into car.

I will install engine in car on Saturday. Hopefully it will go in as easy as it came out. 

Engine and trans ready for car

"Moment of truth" is getting closer. Today engine and transmission were bolted together. The torque converter should not be "pressed" on the flexplate (will probably eat up thrust bearings if done). After gearbox and engine were bolted together the torque converter and flexplate were bolted. Before bolting flexplate and converter I had to slide the converter about 10 mm against flexplate. Important to use correct torque on both bellhouse and flexplate bolts. Engine going back into car after easter.

The flexplate (TCI flexplate for internal balanced engines) was bolted on crank. The engine was supported on the engine mounts and block.

Engine and transmission ready for going back into Corvette

Today transmission was delivered on my door. There was some issues  delivering the torque converter from US - that is why the workshop had to use som extra weeks to deliver the transmission . It is a local transmission workshop which has overhauled and strengthen the transmission. The torque converter is a Borg Warner lock up converter. My knowledge about transmissions is very limited (close to nothing) - but every part of transmission is replaced and it is now capable of handling about 500 HP and over 450 ft-lbs of torque.

The TPIS A/C pulley delete also landed today. This will probably solve my problem regarding length of serpentine belt. I will try to use stock length belt and replace the idler wheel and TPIS A/C pulley delete wheel with overdrive wheels to make it work with stock belt.

The plan now is to commence putting engine and trans back into car after easter. I will spend some days skiing (cross country) the Norwegians mountains the next couple of weeks. Pictures below are …

ATI superdamper 917274 and serpentine belt system

I decided to get an ATI superdamper and it landed yesterday (order by Summit). The damper includes a crank hub and it is special version for LT1 gen II SBC (Corvette C4 92 - 96 model). I had to hone the crank hub to get it on. With the damper installed I could also install the serpentine belt system.
The diameter of the ATI superdamper is 7.530" and diameter of stock damper is just over 7". The stock serpentine belt is to short. As shown on the pictures the drive belt tensioner is not part of the system with stock serpentine belt. Stock belt is 67 or 68 in long. I have measured  inner length of new belt to be about 69 in. I probably need a new belt which is close to 70 in long. I will try a couple of belts and check the marks on belt tensioner to find the correct length. 
UPDATE 1 : finding a correct length serpentine belt with ribs on both sides is difficult. Stock length is OK to find but slightly longer is not easy. 92 models and early 93 models Corvette C4s used serpent…

What´s done?

This year it is engine and transmission which both are completely overhauled.  Next winter brakes and suspension will be overhauled. Picture is engine today (mid February 2012). An ATI superdamper 917274 will be also be installed before engine is going back into car. Last in this post there is a list of whats done.

The following is summarized whats done (engine) this year:
Engine 383 street/strip shortblock from Golen Engines (internally balanced). 16 cc dish Mahle forged pistons (16 cc dish together with 54 cc in top, zero decked is about 11:1 in compression)ARP main studs (4-bolt engine)SCAT Cast steel crank 3.75" strokeScat 4340 Forged I-Beam rods, 6" length, ARP rod boltsTrickFlow 430 HP GenX Top End Engine Kits for GM LT1Heads and cam1.6 roller rockersIgnition MSD Ignition 8381 MSD Ignition Pro Billet LT1 Distributors (optispark distributor)MSD Ignition 32129  MSD 8.5mm Super Conductor Spark Plug Wire SetsMSD Ignition 8226 MSD Blaster GM Coils a new tune from PCM4less (sp…

Engine is done and prelubing engine

Engine is soon ready for going back into the car. There are still some minor work to do before putting it back in the car:

prelube engine and check for oil leaks and oil reaching all vital partsinstall headers and gasket (headers are just mounted for picture)install plugs and spark wires (including heat shield for spark wires)replace water and oil temperature sensorsreplace oil pressure switches (one connceted to ecm and one for the fuel pump)install serpentine belt (and everything which is part of serpentine operation)the balancer - got a new hub but not the right hub. Question now if I should go ATI damper or get the right hub for my stock damper.
The transmission was delivered to a local workshop for full overhaul and strengthen. A new torque converter is ordered from US (by workshop). Next week I will get my "new" transmission, torque converter, external gear oil cooler and transmission fluid from workshop. I will commence installing engine + trans in car by mid March. Y…

Installing oil pump, oil pan and MSD opti

This evening the "bottom" of engine is finished. New oil pump and pickup is installed. I have a new street/strip LT1 oil pan from Canton. The pan requieres a canton pickup.  Before oil pan and gasket is installed both 1-piece rear seal and front cover timing chain has to be installed as well.

Picture below is the 1-piece rear seal. Hopefully I got it right - dont want to experience any oil leaks. If seal is damaged the only way to replace is to separate engine and transmission (and that is not an easy job).

All simmerings in frontcover are replaced. I also got a new AFR harmonic balancer bolt. Dont yet know how to press the crank pulley on  - probably heat the pulley before pressing it on (update : I got a new crank pulley together with ATI superdamper. The new pulley is slightly honed before installed. There is instructions together with superdamper how to install pulley.).

Bottom of engine complete. New knock sensors are also installed. Next now is oil and prime engine.

Adjusting valve train

It is time for adjusting the valve train. The engine fires in the following order : 1 - 8 - 4 - 3 - 6 - 5 - 7 - 2. I´m starting by turning cyl 1 in TDC compression stroke (intake and exhasut valve are both closed). Adjusting both roller rockers on cyl 1 to zero lash and then a 1/2 turn preload before nut on roller rocker is locked. Then turn engine clockwise 90 degrees and cyl 8 is TDC compression stroke. Do both roller rockers on cyl 8. Continuing this and all cylinders a done by 720 degrees on crank.

New pushrods and oil pan received

Last week I checked for correct pushrod length. Last year I bought 16 TrickFlow pushrods of length 7.250". They were too long. I also checked how my stock 7.20" pushrods was (length) - they also were a tad too long.  But with new TrickFlow 7.150" long pushrods the wear mark is spot on center of valve stem. See picture below. The TrickFlow kit comes with guideplates. It is very important that pushrods are made for guidplates. If not you will probably run into problems sooner or later.

I also got a new Canton street/strip oil pan. The pan was mounted and tested for clearance. No problem with clearance. The pan is 7 qt and converted to metric this is about 6.6 litres I belive. 

PTV clearnce

Piston To Valve clearance is easy to check. Get some model clay. Put the clay ontop of piston and put some engine oil ontop of clay to prevent it from sticking to the valves. Mount top with a few bolts (including gasket). Remember to use measure springs to have correct lift. Chad Golen told me that there should be plenty of clearance with my cam profile - no need to check. I still wanted to check (for fun) and as Chad said - there is plenty of clearing for my setup. The exhaust valve does not touch the clay at all, the intake valve is just touching the clay.

Installing valve train

The trickFlow head and cam kit includes 1.6 roller rockers. The rockers are "non self aligning" type and need guide plates for pushrods (which also is included in kit). Pushrods are not included and it is important to remember that guide plates needs special pushrods. I also have hydraulic lifters and that requires special measure springs to be installed before checking pushrod length. Stock valve springs will compress lifters (because no oil pressure) and you will not measure correct length of pushrod. You can use a solid lifter to check with stock springs (it is probably easier to use special measure springs)..

The procedure to check is :

(1) Install top onto cylinders 1,3,5,and 7 (I´m using only a few bolts to keep the head in place). Head-gasket is also installed.(2) Put cyl #1 in TDC (compression stroke).(3) Replace stock springs with measure springs cyl #1 (using a special tool for that)

The goal for correct length is to get the roller part of the rocker to sweep aroun…