308 Engine Rebuild & CIS to TWM Throttle Bodies Conversion Thread!

...too risky?....what a coward


The valvew are probably about the right size. Just looking at one the port really chokes down at the manifold flange and the curves in the manifold don't help matters any. I'd expect about a 20% gain can be had with the stock valves.

 

There was that Louthan guy here on FChat that did porting that had some pretty good prices - what happened to him?

 

I well remember that 'episode' here on Fchat... I wonder what ever happened to that engine?

I think a good general clean up, multi angle seats and light porting (nothing aggressive) with manifold matching would be worth it.

 

It is important not to hire a (completely) crazy person to do the work

 

can understand that . . . keep 'er going

 

I wonder if everyone has stories about their porting guys...

 

probably the reason most of us are on the fence about it . . . numbers don't lie

 

If you ant to make hp you need air, so porting, boost or both are requuired. Time to get off the fence

 

Those heads were most likely door stoppers before they came off whatever engine they were on

 

Hello

Thanks for these interesting topics!

I am building my gt4 distributors, and want to get rid of the weights and points. Timing will be controlled by MegaSquirt trough CDI (Mallory). What optical triggers inside distributor (crane?) have you been using on these twin distributor setups? Is there special installation kit available? I know the cranck trigger would be best and easy, but I also want to keep the distributors.

Thanks, Juha

 

I'm sure Mark will weigh in too . . my Haltech brain was able to read the stock Ferrari triggers.

eidt: this was an injected car . . . don't think you had the crank triggers on gt4's?

 

But for a pair of lock washers it'd be together tonight!

Spent half a day duplicating Sean's rectangular alignment tool. Wanted the fit to be a tight slip fit so there would be no doubt things were lined up.

Things went fast after making the tool.
I lined the control forks up with the tool then snugged their bolts until they would barely slide.

I'd already observed that the middle control fork is exactly the height of the mating right angle lever's end. So I got a pair of jo blocks that would barely press in between the middle (2nd-3rd) & lower(4th-5th) right angle lever's ends. BTW, finger press fit spacing was exactly 2.501 mm.

I then temporarily installed the right angle lever plate, and inserted the Jo blocks between the middle & lower right angle lever's ends.

Next I rotated the 2nd-3rd (ie: middle) control fork down over the right angle levers until the control fork rested on the Jo blocks & tightened the 2nd-3rd fork onto the shaft. I this exactly aligned the 2nd-3rd control fork with the corresponding right angle lever end.

I then used the tool and same pair of Jo blocks to align the 4th-5th (lower) control fork with the middle control fork. The Jo blocks ensured that the upper edge of the control fork was exactly aligned with the corresponding right angle lever's upper side.

Repeated with the 1st-Reverse control lever, but had to use a different set of Jo blocks as the right angle lever ends were slightly further apart. (Forgot to write this spacing down).

Now each control fork is aligned with the corresponding right angle lever's end.

I backed the pressure off of the detent springs & verified that it shifts properly. Finally I double checked the control fork alignment.

WHEW, that's out of the way.

Next I installed the differential. All went well until the very last step of installing the differential (actually, it's also the last step of the tranny restoration!!!) which was to install the half shaft flanges.

When I was cleaning the old sealant off of the bolt & washers, I discovered that the lock washers for the 12mm flange bolts had taken a permanent set. I also discovered I'd never gotten around to buying some 12mm lock washers!

So I couldn't finish the job tonight. A trip to the hardware store & half an hour tomorrow will see this project finished at last!!!

 

Wow - after reading that I had to take a shower!

 

Yep, with a camera!

It's a while since I last heard someone speak of a Johanson block?

 

Good job!!


Did you take the ring nuts and bearings off this tranny and re-assemble it all again? I'd like to hear what the bearing fit was like on the end of the 1st/Reverse cluster . .. and how you final assembled that . . .I posted how I did it and was curious if I was making extra work the way I went about it.

Cheers

 

Are you referring to the ring nut on the lay shaft's rear end & the bearing w/a flanged outer race & duai inner races that love to come apart?

I took a piece of steel pipe (Home Depot), trued the ends square, & slightly bored it out until the inside would just barely clear the shaft bearing mount surfaces.

First used it to drive the clutch end bearing races onto the main & lay shafts.

Meanwhile a 250W work light was heating the transmission case's rear to help the outer races slip into place. The light was face down facing into the rear section of the tranny case with a cardboard box over it. After about 20 min, the tranny case had expanded enough so that a used outer race would easily slip into place & back out. The lamp was used to keep the case hot during the next steps:

Both rear end bearings were hand packed with high moly CV joint grease to help keep them together during assembly. Outer races were placed in the deep freeze for 15-20 mins to shrink them as much as possible.

Main & lay shafts were inserted together from the tranny's clutch end. Lay shaft was worked thru the 1st/Reverse gear & bearing stack (Royal PITA if you're by yourself, not too bad w/a 2nd pair of hands) until both shafts were seated inside the outer bearing races in the central web.

I'm not sure how I would have done this step if w/o a 2nd person helping:

I had someone holding onto the clutch ends of both shafts so the next step couldn't drive them out of place. One of the rear bearings was slipped onto the shaft, & the innermost inner race was going on true, I used a 1 lb brass hammer to gently tap around the pipe's end, thus driving the bearing into place. Once I was sure that the outermost inner race was on the shaft, ensuring the bearing wasn't going to come apart, I started tapping with a bit more vigor until the inner races were in far enough for the ring nut to go on for 3 or 4 threads. I then used a breaker bar & socket on the ring nut to press the bearing on the rest of the way. At some point in that process the outer race easily slid into the tranny case.

Repeated for the main shaft.

Once I was sure that both outer races were fully seated against the case, I removed the heat & let the case cool & shrink onto the races.

BTW, partwary thru a professional ferrari tech dropped by & said that was the same way he did 308 tranny rear bearings.

Can you post a link to what you did? Tried searching but must have had the wrong key words.

 

Half shaft flanges are on & quad shift shaft seals are installed. Even temporarily fitted the cover to keep the detent balls & springs in place & dust out of the gears...

 

I explained it in this thread post #152 . . you responded post #153 thinking these bearings have to be assembled on the shafts before you put the shafts in . . you did it pretty much how I did it only I fit the innner race to the shaft instead which is how the 3 gearboxes I've taken apart have been instead of driving that bearing on with inteference fit . . . if you think about it a little more, it could be a complete nightmare to take the box apart again if the inner races are real tight on the shaft on that end 'cause you have to remove the shaft from those bearing races/gear clusters inside the box . .. anyway just sharing my experience and thougts.

cheers

 

You did not pick it up yet!