2.5 MFI Engine - Holiday Project
 

Here is a sneak peak at what I'll "hopefully" be doing between Christmas and New Years...

Short Stroke 2.5 MFI - Building it to be a fun street motor.

- 77 7R Case
- 66mm Counter-Balanced Crank
- 2.0S Nitrated Rods
- 3.0 Aluminum Oil Pump
- Mod-Solex cams (camgrinder special - profiles between E and S cams)
- Carrera Chain Tensioners
- 90mm Mahle Nikasil Cylinders
- JE Pistons 10.5:1 "RSR Style" (hopefully about 9.5:1 with the 66mm crank)
- RS Spec Heads
- Complete Stock 2.2S MFI setup (well one modification to the pump)
- Single Plug 2.4 distributor

All the machine work being done by Henry @ Supertec.

I'll post some pictures soon..... Merry Christmas

Hi John
70.4 mm stroke
90 mm bore
1.0 mm deck
69 cc chamber
28.2 cc dome
equals 10.5 to 1 comp ratio

change only the stroke.
66 mm
90 mm
1.0 deck
69 cc heads
28.2 cc dome
equals 9.9 to 1 comp ratio

MERRY CHRISTMAS TO YOU AND YOURS

Hey Henry....

I think when we spoke you suggested going to a deck height of about 1.25 which would bring it down closer to 9.5:1. That was the plan. I'm also thinking that JE's 10.5:1 estimate assumes a perfect world and that I wouldn't actually get that.

When we built my 2.5L we had custom J&E's made because their off the shelf pistons do not always match the CC of your head. We CC'd the heads, and then told J&E what we wanted so we were sure of the compression.

All 90 mm JE pistons are custom made. At this time JE does not offer a shelf 90 mm.
As stated in my calculations, all necessary specs to produce the proper pistons are listed.
That is all except valve size.
At this time we are putting larger valves in 2.2-2.7 heads.
Because I know what size valve John is running there was no reason to list valve size.

I meant when you order them from EBS Racing "Off the Shelf"

John-
What will the port size be?
-Scott

I'm going with 36/36 and a stock 2.2S MFI setup. I didn't make as much progress as I had hoped but I'll post some pictures soon.

John-
It sounds very much like the motor I'll be putting together in the next few months. I'll be using my '70E cams and E pump, and standard sized valves. Otherwise, identical. Why is Henry increasing the size of the valves with 36mm ports?

I'll be very anxious to hear how it runs. My car won't be on the road until August.
-Scott

He isn't... I'm using stock valves. My heads are essentially 2.7RS spec MFI heads. I think he was just saying that he now offers larger valves for the early 2.2/2.4/2.7 heads. I'm hoping to get this done in the next month or so....

That's what I thought. Please keep us posted!

I didn't make as much progress as I would have liked to but here are a few pictures:

http://forums.pelicanparts.com/uploa...1136523614.jpg

My "Assistant" installing the bearings

http://forums.pelicanparts.com/uploa...1136523686.jpg

http://forums.pelicanparts.com/uploa...1136523725.jpg

http://forums.pelicanparts.com/uploa...1136523757.jpg

http://forums.pelicanparts.com/uploa...1136523874.jpg

I'm hoping to get time this weekend to make the necessary measurements to calculate the CR.. More to come :)

Nice pistons; what do you expect the CR to calculate to?

As you can see from Henry's calculation, the theoretical CR will be about 9.9:1 with the 66mm crank using a 1mm deck. I'm hoping to get it down to about 9.5:1 without going above a 1.25mm deck. I'm going to CC everything this weekend and calculate the expected CR and I'll let you know.

Ah, I missed that part of Henry's post. Why are you trying to back it off? If you are using 2.2 - 2.4 heads, they should be just fine at 9.9:1 even with single plugs.

What kind of horsies will something like this make?


JA

I just want to get the CR down to a reasonable level to avoid detonation. We have some weak gas here in California. :)

I'm not sure what the HP will be (maybe 200).. Henry can probably help with this.

Here is the dyno sheet from my 2.5L short stroke with 10.5:1.
http://forums.pelicanparts.com/uploa...1136652304.jpg

More info on this thread:
http://forums.pelicanparts.com/showthread.php?s=&threadid=236999&highlight=2.5L+d yno

Those are great dyno numbers... What type of gas are you running? Did you measure the CR to see if you got was JE quoted? Very nice motor.

Thanks. I was also impressed by the work of Aase Motors.
This is my race car so I use 110 octane.
Allan at Aase CC'd my heads and gave a custom order to J&E for a true 10.5:1 compression. Not the "off the shelf" pistons you can buy from EBS or others.
I'm in the process of building a back up Long Stroke 2.5L at Aase's Shop. I want to have one of each :)

They do nice work.. I know one of the guys over there and without a doubt they know what they're doing. I'm building a street motor so I'm trying to keep the CR down around 9.5 to 9.8 so it will run on our wonderful CA pump gas :)

I just got done doing all my measurements and it looks like I need some 1mm base gaskets which will give me about a 1.15mm deck which should be about 9.75:1

Latest Picture. Hopefully I'll make some good progress next weekend.

http://forums.pelicanparts.com/uploa...1136871128.jpg

Made a little progress this weekend. I installed the 1mm base gaskets and the P&Cs. I ended up with a deck height of about 1.2mm. I ended up making a tool to install the JE wrist pin clips - it worked great. I posted some pictures of the tool on another thread

http://forums.pelicanparts.com/911-engine-rebuilding-forum/258950-je-piston-pin-cilps-post2351986.html#post2351986

http://forums.pelicanparts.com/uploa...1137387154.jpg
http://forums.pelicanparts.com/uploa...1137387167.jpg

John-
What method did you use to measure deck height?
-Scott

The JE pistons have a flat surface around the edge so I used the basic measurement from the flat surface to the top surface of the cylinder.

We installed the freshly powder-coated cylinder heat deflectors and the heads. We also drilled out the plugs and removed the oil spray bars from the cam housings. Hopefully next weekend we can get the cam housing installed and start on the cams and rocker arms.

http://forums.pelicanparts.com/uploa...1137989295.jpg

http://forums.pelicanparts.com/uploa...1137989310.jpg

Gonna be a great motor!

I can't help but say that I have a little guy about that age who would not think twice about dropping a bolt or a marble or anything that he thought fit nicely right into one of those intake or exhaust ports. I even heard of a story where a little boy did just that to a $20K+ turbo motor. When the motor came back, sure enough there was a foreign object (that doesn't belong in any kind of motor) found as the culprit of destruction. I only say this as I have this fear of my own.

Best on your project. Anxious to see it come together.

JA

:)

That wouldn't be good!!!

It could certainly happen but this kid is not your typical 5 yr old. He can't wait for the weekends to go in the garage and work on the engine. Even though he is so young he focuses on what we're doing and is very careful. He asks hundreds of questions and even catches a few of my mistakes (missing base gasket, CE ring, etc...). He also counts all the parts and hands them to me - great assistant. Most importantly we get to spend time together.

I certainly wouldn't be happy if I ended up with a marble in the engine but to me it is worth the risk... If this wasn't quality time spent with my son I probably wouldn't be building the engine - lucky for me he enjoys it as much as I do. As a side benefit he is learning a lot in the process.

...and don't ask how excited he gets when we drive down to Henry's shop (Supertec) on the weekends to pickup/drop-off parts..WOW

We're having fun and we hope to enjoy an excellent running engine in the near future.....

Now my 3 yr old... that's another story :)

Here is the latest....

We removed the plugs, cleaned the cam spray bars, and installed new plugs.

http://forums.pelicanparts.com/uploa...1139246491.jpg

Spread on some Threebond 1104 and installed the cam housings.

http://forums.pelicanparts.com/uploa...1139246561.jpg

We got everything torqued down and test fit the cams..... and they spin great!!!

http://forums.pelicanparts.com/uploa...1139246679.jpg

http://forums.pelicanparts.com/uploa...1139246714.jpg

My wife's birthday is next weekend so there is a good chance we will see little progress for a couple weeks ;)

A few people have asked about the Mod-Solex cams that are going in this engine. These are a compromise between E and S grinds. John Dougherty (camgrinder) made them for me on a set of MFI E cams. Here are the specs from John

http://forums.pelicanparts.com/uploa...1139592041.jpg

Hmm. Cool. Comparision data.

E & L
I 238 230 .405" 102 3.0-3.3 mm
E 226 222 .393"

SOLEX
I 248 242 .455" 97 4.2-4.6 mm
E 236 230 .414"

EARLY "S"
I 268 263 .455" 98 5.0-5.4 mm
E 240 235 .399"

Slowly but surely.....

We installed the chain housings, mfi camshaft seal, and camshafts

http://forums.pelicanparts.com/uploa...1140548659.jpg
http://forums.pelicanparts.com/uploa...1140548684.jpg
http://forums.pelicanparts.com/uploa...1140548710.jpg

...and I couldn't resist getting a glimpse at what it is going to look like with the fan (I got it already powder coated and cad-plated from Henry @ Supertec).

http://forums.pelicanparts.com/uploa...1140548806.jpg

Last time I was on the phone with Henry he mentioned that my engine was looking a lot like a Supertec engine.... Well that's because he has supplied all of the machine work and most of cad-plated parts. Wait until you see it with the MFI injection :)

More to come...

John, I just sent my MFI stuff off to him last week. :) Can't wait to get it back!

Those are the aluminum chain boxes? Are you using the Al covers also?

Hi Bill -
Yes.. I'm going with pressure feed tensioners so I just picked up a complete update kit which includes the AL covers.

Well it's been a couple weeks and I didn't get much done. I did align the sprockets and set the cam timing this weekend so the rest of the longblock assembly should go quickly. Hopefully after next weekend it will be ready to install the MFI setup.

http://forums.pelicanparts.com/uploa...1142224322.jpg
http://forums.pelicanparts.com/uploa...1142224349.jpg

Here are some pictures that bring the project up-to-date. Everything is done and I'm just waiting on the MFI setup. So far everything has gone together well. I'm looking forward to getting it done and into the car. More to come.....

http://forums.pelicanparts.com/uploa...1146452005.jpg

http://forums.pelicanparts.com/uploa...1146452030.jpg

http://forums.pelicanparts.com/uploa...1146452063.jpg

http://forums.pelicanparts.com/uploa...1146452080.jpg

http://forums.pelicanparts.com/uploa...1146452097.jpg

Looks sweet. Is that "the" 77 case, by any chance? ;)

Scott

Project was on hold for a while. I made some progress recently and here are the latest pictures. I should have it done next weekend.

http://forums.pelicanparts.com/uploa...1153109452.jpg
http://forums.pelicanparts.com/uploa...1153109465.jpg
http://forums.pelicanparts.com/uploa...1153109482.jpg
http://forums.pelicanparts.com/uploa...1153109502.jpg
http://forums.pelicanparts.com/uploa...1153109517.jpg

More to come :)

John,
I see you have the pump modified and noticed the oil flow line on the pump are sealed closed...so no oil flows through the pump.

Nice job Henry!!

Vr,
Bavaria911