3.0RS...spoke with andial

[82SC]

well I talked to Peter at Andial...very helpful guys

he said that an S-cam on a SC engine would be ok...even with the CIS pistons...he said it would be close but def possible...

is that true? Andial are the experts, but I had never heard of that.

so from what he said I could start with an SC engine
add S-cams, and MFI and I'd be set...

anyone have suggestions with how to plan this motor out?
I am gonna keep it single plug...I am thinking a later motor may be a better starting point because of the slightly high CR...

I guess I can have the head port size increased to that of the early SC if needed...

If there is interference with the valve and piston, can I have small valve pockets machined in the CIS pistons?

hmmm...thanks for any suggestions

MJ

[Elombard]

If you are going to Notch pistons might as well start with an early SC core and put in euro/aftermarket/ or whatever pistons.

A bigger problem might be the MFI. I am interested in doing a similar conversion but I was going to go Webbers because I heard that the MFI would be very difficult to adapt to an SC motor. i.e. the Injection ports in the heads are not there, the drive for the MFI pump is not there.

Did Andial say this could be done reasonably easily?

I just love the MFI systems!!!

[Wayne 962]

Gosh, someone must have misunderstood someone along the line. CIS pistons *will not* work with an 'S' cam. Not without modifying the piston, which I don't even know if it's possible to modify it to work with 'S' cams.

I'm surprised as all of this 'advice' seems off-base. First of all, a 3.0L MFI system will be very expensive, as it will have to be all custom-made and modified. As mentioned, no drive on the cam, and no ports in the heads. ?!?!?

The CIS pistons are not a HP piston - you won't get good flame front travel, etc. They should be only used with CIS systems (Motronic = same thing).

What are your goals for this engine? Nothing is cheap and free...

-Wayne

[82SC]

hmmm I double checked and asked him a couple times...about the CIS pistons and S-cams. I didn't think so too that is why I posted.

he said it would be close...but he said it was a def possibility

with the MFI:
rennsport systems says putting the MFI injection ports is simple machining

I think if I bought used S-cams and machined an opening in the back of the case then the MFI pully can be added no?

and the pump needs to be rebuilt and I think the rebuild price of any pump and getting one made for this formula is the same. I spoke with Gus a while back and he seems to have a big database of different space cams




my goals is something fun and perky for the street. I was orignally planning a 2.7RS clone...then there is 2.9...3.0...andial said the 3.0 would be much more reliable and may be a better option....well I still have months b4 the engine work starts...I have to work on chassis/interior/suspension first...

I am very open to suggestions...but my criteria are definately MFI...and very fun

[dtw]

I posed a similar question to a couple of experienced builders, the pistons in question were 2.7CIS pistons. These were an option for me for about 30 seconds. The builders said an S cam could be made to work, but that the engine would be a real dog anyway. Incidental to your scenario also, they mentioned that tuning the MFI to work efficiently with the pistons would be nearly impossible. As Wayne and countless others have said, CIS pistons don't like anything but CIS.

Have you actually looked at the CIS piston? The odd dome on those things is just begging to be smacked by a hot-cammed valve. It is not recommended to machine relief into them, nor does it make any sense- you are spending money to machine a dog of a piston.

Keeping the CIS pistons is questionable when new JEs can be had for very reasonable prices.

Are you sold on MFI? Note that you will incur thousands in expense getting MFI to work on a custom engine (custom space cam, bored t-bodies, machined heads for injectors, MFI electric fuel pump) If you're going to spend thousands on custom MFI, that makes the idea of keeping CIS pistons even more outlandish.

With respect to your request for help planning out the engine- what are your goals for the engine and what is your budget??

EDIT: I just saw your followup post. Many of my questions still stand. Additional response to your post:
-Machine what case? You have to have the cam drilled for the pulley, and you must cut an opening in your engine sheetmetal for the belt to travel. That's no big deal. It's all the other crap that is going to cost you cubic cash.
-Fun engine, OK. Do you have a base engine to work with yet? Sounds like no. If not, grab a core 3.0 and build it up. I'd suggest some high CR JE pistons, S or GE60 cams, Webers, headers (SSI if you still want heat), and a loud and open muffler. If you are stuck on MFI, fine, just realize the cash involved. There is a laundry list of small mods and upgrades to do while the engine is apart but you get the idea.

[speeder]

I admire your ambitious-ness, but wouldn't it be a lot easier and possibly cheaper, (unless your time is worthless), to just buy a hot MFI motor w/ the car it came in??

Those motors are upgradable and already have all of the right (major) parts. Plus the car would be worth something to someone other than yourself when you are done. Just playing devil's advocate, but always remember the old sailing joke: "like standing in an ice-cold shower, tearing up hundred dollar bills."

[82SC]

yeah I have been thinking that too...

do you buy a low displacement and bump up displacement...

or do you buy high displacment and backdate induction etc...

you think using a 2.4L MFI or a 2.7L CIS will be better to make a 2.7RS...

although that magical 3.0L is very tempting...I have months and months to decide...the car is now at KevinP's shop...signal orange here we come...

btw I saw a SWEET signal YELLOW at TRE today...that color started growing on me as well...

if anyone can spell out what the would do in my situation...with a budget of lets say about 5-8K...trying to stay on the low end...that would be great...(FYI I have a S MFI setup (throttle bodies, stacks) and an unknow MFI pump already)

MJ

[makaio]

MJ, why not just put a 3.0 or 3.2 in there for now, with OE (CIS or Motronic) injection. Then when budget allows (when you get that MD DR title), you build that wild MFI motor .

[techweenie]

Seems like the hot topic these days. had a mechanic pushing me to do that two weeks ago.

But correct me if I'm wrong: SC cam towers have four bearings.

The last of the MFI engines was a three-bearing cam (2.4 & 2.7 RS) yes?

So where do you get the MFI pump drive off the back (front) of the drivers'side cam shaft? Do you have to weld one on to a four-bearing camshaft?

techweenie

[CamB]

Rebuilding MFI pumps, cams with pump drives, machining all sorts of crap left right and centre. Spare MFI stacks

This is screaming make my MFI into EFI at me



The challenge is cheap EFI.

[Bobboloo]

For the record. There was a four bearing MFI cam. It was first used in the 2.8 RSR and later in the 3.0 RSR. Of course these are unobtainium parts.

I don't see a 3.0 MFI that difficult in this situation in that he has the S stacks and throttle bodies already. The stacks are the hardest "part" of the equation.

Drilling a cam to except the pulley for an MFI pump is not that big of deal. 4 threaded holes to be exact. You also need the extension piece for the pulley. Cutting tin is easy as well.

Also modifying the head for the injectors is not a big deal either. Ollies in Santa Ana can do these mods at a reasonable price.

I would suggest that if you start with a 3.0CIS motor that you go to 3.2 in your rebuild because it'll be about the same price. Specially if the cylinders have wear which means they'll have to be re-bored and plated. I think the price of 95mm or 98mm JE Pistons are the same.

Starting with a 2.4MFI is not a great starting point unless it's an S motor. It's cheaper to convert 2.7 CIS S heads or for that matter 3.0 CIS SC heads than to port 2.4 Tor E heads.

Cam, That's one beautiful MFI imposter.
P.S. That's not where you plug in the backup light cable.

MJ what's the part number on that pump? I'll tell you what it is.

Bobby

[speeder]

2.4 motors can be built to 2.9, can't they? That's close enough to 3.0, I would think. Are you building a race car or street car? Totally different objectives, a race car can have ALL of it's power at the very top, it doesn't matter. A street motor you want to have heaps of torque, I would think. Oh yeah, and drivability+ run good on pump gas, etc. And you have to weigh your investment of time/$$ vs. enjoyment you will reap from beast.

My '82 SC w/ the mods I am doing, (cams, SSIs, alum. pp, etc.), won't be the fastest car on the road, I drive next to 400hp cars every time I leave the house, but it will leap over slower traffic in a single bound and get 24mpg at 80mph on 87 octane. And deliver fun going to the 7-eleven. Just food for thought.

[Wayne 962]

A 3.0L MFI motor done right would probably cost in the range of $12K. For that money, you can buy much more, including an engine management system like the TEC-3.

You should really buy a copy of my new book, it answers a lot of these questions in there.

You can use the 3-bearing cam towers with the 3.0L case if you need to use the MFI 'S' cam.

-Wayne

[82SC]

i think one of the main purposes of this board is drag my lofty goals back down to earth...hahaha

but I have not lost hope

so okay budget: 5K-8K
All DIY with the new engine book so most of the money will be parts and machining

i guess cheapest route is to get a 2.7 or a 3.0 CIS hope the jug can be reused with JE replacement pistons and the slew of MFI backdates

or get a 2.4L use new pistons and cylinders to get to 2.7-2.9L

I think maiko is correct in getting a running engine for now and do more planning on this engine....I think I may be anble ot invest more money into it if I am patient.

OH...I know one of my S throttle bodies needs to be rebuilt, but I was wondering what the TB size would work optimally with?

I know getting TB bored is pretty pricey...I am not sure what size the S TB's are, but if then need extensive work, and the stacks need to be bored for 3.0L then I think that would push me towrds 2.7....

but I'd love to hear other's thoughts on what they would do...

thanks

MJ

[CamB]

"P.S. That's not where you plug in the backup light cable. "

That explains everything!!!! I wondered why I was getting big balls of flame out the back when I lifted off at high speed in reverse.

MJ,

My TBs came bored to 40mm. This seems enough for the engine (a 3.2) as a street car (it has 245hp at the wheels).

[Superman]

I'll join the chorus here and warn that on a project like this, you will spend so much money and time that you might be better off just buying a nice race motor. There are many options, some of which get you lots of horsepower for not that much dough.

On the other hand, I'd like to take this opportunity to ask the rest of the critics here what it might be like to drive an over-square 3.2L S-cammed MFI engine, particularly if it had high-compression pistons. Eh? MFI, S-cams, 3.2 liters? Do I make myself clear?

[ttweed]

Originally posted by Superman
I'll join the chorus here and warn that on a project like this, you will spend so much money and time that you might be better off just buying a nice race motor. There are many options, some of which get you lots of horsepower for not that much dough.

That's what I did. I found a nice 3.4 race motor for less than $8000 that makes somewhere north of 300 HP. Of course i have to run $3.50/gal. gas in it, but it should be fun in a 2400 lb. car.

MJ- I have a solution for you. Buy my old 1980 SC motor and put it in your Targa. It's all stock except for SSIs and a sport muffler and MSD ignition. Makes a good, grunty 200 HP. It's tight, no leaks, new airbox and injector seals and a fresh top end. Less than 70,000 miles on the bottom end. You'll have it in the car and running in no time. Later on you can take the CIS off and build it up.

[Bobboloo]

The stock 3.0 with SSI is a good no-brainer. MJ is just thinking aloud. What if...?
I do the same thing all the time. What if? Tweeds motor sounds like a good option. Better yet find yourself a wrecked SC so can use all the other parts your gonna need that will otherwise nickel and dime you to death.

Superman, the exact motor you speak of is in Kurt Starnes 72' T Coupe. A 3.2MFI S cam built from a 3.0 with 98mm P+C's built by Blackforest. It's a slight improvement from the 2.7RS POS that MM built. By the way. Has anyone seen or heard from Kurt? I last saw him at California Speedway this summer.

Bobby

[82SC]

yep I always think out loud on this board...and it is helpful to have more knowledgable members sift through my thoughts and weed out the improbable ones...

the targa project is adding up fast and from day 01 I've been planning to buy an engine that can be used immediately...all the resources are into the ext, int, brakes, susp right now...

I am trying to come up with what the final layout of the engine will be....

plus the SC is good since I am familiar with my SC...

well I'd still love to hear some other guys think out loud about what viable options are out there

MJ

[Wayne 962]

A 3.0 MFI engine would be a fantastic project, and almost a one of a kind engine. Except for vintage RSRs, I've never seen a street MFI 3.0L engine. It would indeed be incredibly cool. But it would probably cost $12-15K to do it right. For that type of $$$, you can do a lot more (Engine management, even SuperCharger?) - this is the reason why I think that we don't see this configuration more often. It would only be really useful for a vintage car that would want to maintain the stock look...

Besides, it's way easier to strap carbs on the 3.0 which is what most people do in these circumstances...

-Wayne