Cam Swap, Engine All Together Options

[dereknlee]

I have a decision to make and could use some advice. My 1.7 engine was completely re-built into a 2 liter in 2012 by a local shop. At the time the plan was to run 40 IDFs so a Webcam 86 (00-152) cam was installed. My 914 hasn't driven since 2008 and has been an on-again/off-again project ever since, so the rebuilt long block has never run.

Well the 914 project is back on again and in the intervening years I've decided to stick with D-jet. I talked with Webcam, they said the 86 grind isn't too different but that they recommend a 73. And they generously offered to exchange for the cost of shipping (assuming the cam condition is as new).

Swapping the cam is a bit intimidating as a project, but I have some engine rebuild experience and have done enough wrenching that I think I could muddle through.

My questions are as follows:

1) If in my shoes would anyone not change the cam? My consensus from searching this forum is that the 73 is the grind to go with for injection and 86 is for carbs. But the conversations are usually had while someone is doing a rebuild anyway and looking for the optimal cam.

2) Is there a minimally invasive way to get to the cam, or should I just follow engine rebuild instructions and pull everything apart? Haven't found anything in my searches on this or other forums to suggest there is any option here.

3) Should I really just have a shop do this? The warranty on the rebuild has long expired. But the possibility for mistakes that could take down the otherwise good rebuild abound (or so I fear). Are there any steps in this process that require experience or special tools that someone who is book taught on this process is likely to mess up?

Here's a picture, because walls of text are boring:

(IMG:http://www.914world.com/bbs2/uploads_offsite/www.thesamba.com-14259-1587828462.1.jpg)

Thanks!

-Derek

[PlaysWithCars]

do You have a complete and known working D Jet system for the 2L?

If not, and you’re considering paying someone to break the engine down and can swap (which will be a bunch of work and cost since the pushrods will have to be remade with the new geometry, etc), why not instead switch to a more modern EFI system? Even the simplistic system can be tuned to work with a ‘carb’ cam with little difference than an old FI grind. Cost may not be so different, and you won’t have to deal with old electronics. If you’re not too concerned about the stock look, Mario at the dub shop seems to have some pretty nice setups which aren’t too costly.

(IMG:style_emoticons/default/agree.gif)
Fuel injection (IMG:style_emoticons/default/beerchug.gif) over carbs, but I wouldn't spend the money to swap cams. I'd do as Jim suggests and build an FI system for the motor you have. You've noted that your motor isn't a stock 1.7 anymore, so the 1.7 FI system isn't going to function properly without some tweaking. Cam swap + FI tuning is probably going to cost as much or more as just building an FI system to match what you have. Instead of ending up with a non-original lower hp solution, why not embrace that its not stock and build an FI system to match the motor you already have?

I also think the color is great by the way.

[dereknlee]

(IMG:style_emoticons/default/agree.gif)
Fuel injection (IMG:style_emoticons/default/beerchug.gif) over carbs, but I wouldn't spend the money to swap cams. I'd do as Jim suggests and build an FI system for the motor you have. You've noted that your motor isn't a stock 1.7 anymore, so the 1.7 FI system isn't going to function properly without some tweaking. Cam swap + FI tuning is probably going to cost as much or more as just building an FI system to match what you have. Instead of ending up with a non-original lower hp solution, why not embrace that its not stock and build an FI system to match the motor you already have?

I also think the color is great by the way.

This is an interesting idea you both bring up. I have read that to get the Djet to work with the bigger engine the MPS will need to be adjusted. But nothing I read on the board suggested that was a particularly expensive or difficult job. Is there going to be more to it than that? The dubshop kit is almost $3k, seems like for that much I could almost undo the engine changes and go bone stock.

[JamesM]

(IMG:style_emoticons/default/agree.gif)
Fuel injection (IMG:style_emoticons/default/beerchug.gif) over carbs, but I wouldn't spend the money to swap cams. I'd do as Jim suggests and build an FI system for the motor you have. You've noted that your motor isn't a stock 1.7 anymore, so the 1.7 FI system isn't going to function properly without some tweaking. Cam swap + FI tuning is probably going to cost as much or more as just building an FI system to match what you have. Instead of ending up with a non-original lower hp solution, why not embrace that its not stock and build an FI system to match the motor you already have?

I also think the color is great by the way.

This is an interesting idea you both bring up. I have read that to get the Djet to work with the bigger engine the MPS will need to be adjusted. But nothing I read on the board suggested that was a particularly expensive or difficult job. Is there going to be more to it than that? The dubshop kit is almost $3k, seems like for that much I could almost undo the engine changes and go bone stock.

The dubshop kit is a full system with induction which you wont need if you already have the d-jet manifold, throttle body, etc. ECU, wiring harness, crank sensor, possibly injectors are all you really need to convert d-jet to MS.

You never mentioned what d-jet setup you have, or what was done to convert your 1.7 to a 2.0 though. We know the current cam will be an issue with D-jet but there are other potential hiccups as well depending on the details. If you dont have a stock motor, and the correct matching d-jet system for that stock motor I probably wouldn't mess with d-jet. Im sure you can make it run, you might even make it run "ok".... I wouldn't expect more than that though.

[dereknlee]

You never mentioned what d-jet setup you have, or what was done to convert your 1.7 to a 2.0 though. We know the current cam will be an issue with D-jet but there are other potential hiccups as well depending on the details. If you dont have a stock motor, and the correct matching d-jet system for that stock motor I probably wouldn't mess with d-jet. Im sure you can make it run, you might even make it run "ok".... I wouldn't expect more than that though.

Going from the build sheet: 96 mm pistons, DPR counterweighted crank M10/STD-4 (not sure what that means), reconditioned rods, 1800 modified heads 42 intake / 36 exhaust, 61 cc chamber with .060 deck, compression ratio of 8.05.

If you still have the main D-Jet induction then you can build your own Microsquirt setup for under 2 grand:

https://tgadrivel.blogspot.com/2020/03/on-m...914-part-1.html

Read through the entire blog post this morning. Very impressive work, and well written too!

At the beginning of the read I was on-board and thinking microsquirt is exactly what I should do. Then after a few pages in the magnitude of the project became evident. Obviously do-able, but from where I am at with a car in pieces it seems like piling on another big project. I agree that trying to make a 1960s technology do what it was never intended to makes no financial sense given the much better alternatives available. But being able to use the factory wire harness, components, diagrams, manuals to setup and maintain the vehicle carries a lot of weight. If that means I should seriously re-think installing this bigger engine in the car, or try to cobble together a factory 2.0 Djet system instead - then maybe that is what I should do. (IMG:style_emoticons/default/confused24.gif)

[JamesM]

You never mentioned what d-jet setup you have, or what was done to convert your 1.7 to a 2.0 though. We know the current cam will be an issue with D-jet but there are other potential hiccups as well depending on the details. If you dont have a stock motor, and the correct matching d-jet system for that stock motor I probably wouldn't mess with d-jet. Im sure you can make it run, you might even make it run "ok".... I wouldn't expect more than that though.

Going from the build sheet: 96 mm pistons, DPR counterweighted crank M10/STD-4 (not sure what that means), reconditioned rods, 1800 modified heads 42 intake / 36 exhaust, 61 cc chamber with .060 deck, compression ratio of 8.05.

If you still have the main D-Jet induction then you can build your own Microsquirt setup for under 2 grand:

https://tgadrivel.blogspot.com/2020/03/on-m...914-part-1.html

Read through the entire blog post this morning. Very impressive work, and well written too!

At the beginning of the read I was on-board and thinking microsquirt is exactly what I should do. Then after a few pages in the magnitude of the project became evident. Obviously do-able, but from where I am at with a car in pieces it seems like piling on another big project. I agree that trying to make a 1960s technology do what it was never intended to makes no financial sense given the much better alternatives available. But being able to use the factory wire harness, components, diagrams, manuals to setup and maintain the vehicle carries a lot of weight. If that means I should seriously re-think installing this bigger engine in the car, or try to cobble together a factory 2.0 Djet system instead - then maybe that is what I should do. (IMG:style_emoticons/default/confused24.gif)

What is your ultimate end goal? Starting from where you are at currently, from a cost standpoint I suspect getting to a stock 2.0 L d-jet setup would probably cost you a good deal more than going megasquirt on your current engine given you would need 1. A stock 2.0 motor and 2. a 2.0 d-jet system, neither of which you currently have. the build sheet didnt specify what size the crank was, but with 96mm pistons you are most likely sitting with either a 1911 or a 2056 with modified 1.8 heads, didnt specify if they were converted to 3 stud or not but i would assume not, so you would be stuck starting with the 1.7 d-jet parts which will choke that motor.

Personally I would give up on the idea of d-jet with that current motor, I would only recommend tearing it down again to make it d-jet compatible if you like burning money for an engine with less performance.

Only 3 options i see that make sense here:

1. Run the carbs (I am not at all a fan of carbs but they are your easy button for sure here)
2. Run Megasquirt or some other aftermarket EFI
3. Buy a different engine.