V-12 Engine into 308 Build, over on Grassroots

I've put 348 heads on the 4L monster build. Better flow, better valve angle etc... Drop on fit. Only thing needed is tapping the holes for the cam tensioner, casting is already there.

328 and QV cams drop right in. Ports are better etc... Pulled 600+ hp NA. I'd go with 348 heads if you can get them.

 

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Living La Vida Yoda?

 

Man, there is so much cool stuff in that photo!

 

Oh come on, you can't post huge numbers with no real specs, that's just wrong....I thought we were friends?

150hp/liter is a big number, well done!...makes me glad I have 5.4 liter to work with so if I lose and still win....and my decklid will fit

riddle me this.....why are the TBS angled out instead of in on that thing? Injector angle?

and are the 348 valve angles actually different? I did not know that.....I looked and the heads and saw no difference and I'm sure a degree or 2 doesn't matter much....I got the my TR head (20/21 degrees so not as good as QV) u to [email protected] started life at 94....but have to be close to that number +/- to hit 150hp/liter

..at least this spec......what did you do for headers? I know on my engine I'm probably leaving 50hp on the table using the smallish tube tri-y setup but they fixed a huge dip the simulator predicted around 3500-4500....so it seemed worth it for a street engine......but moe hp is wonderful

also, did you play with stack lengths? DM6 is telling me 10.25" (basicaly just a radius on the TB) is the winner but shorter but tunign to a short length, 6ish would be better but is impossible. you must be..16? that is what DM5 was telling me but DM6 says not so much.

 

I think I have a thread on that build... Lemme see..
The engine honestly scares me, have yet to crack past 25% throttle on the street. It'll rev to 14k... Yep 14k ... I get nervous around 11k. With boosted engines there's a power build.. This thing is almost a light switch...idle...BAM!

Let me see if I can dig up the thread...

 

Ok, 14k......with a 79mm stroke? that does not seem prudent?

Now I don't feel so bad about the hp/liter number...I'm expecting about 150-160, but at 9000. retuned for 11k would be 160-170....but I thought better of that plan.

 

https://www.ferrarichat.com/forum/threads/itb-4l-progress.521995/

https://www.ferrarichat.com/forum/threads/engine-jewelry.501444/

 

Yeah I need to correct that.. The on paper design goal is 14k... I've only taken it to 11k no need to really go past that as the curve is dropping.

I'll have to dig up pics, by the pistons were designed the 430 ones, assymetric skirts that are barely a whisper... I'm losing track of these builds but I think this one also sports Ti rods..I think..

 

I'm looking for ~400bhp, and a modest redline - I want to be able to drive this thing without having to notify air traffic control...

 

Thank you for your detailed response/

I was asking for my BBi. From what I understand real comp ratio on these cars is in the 8.8 range not the stated low 9s. The pistons and rings are apparently pretty crappy too. From what I hear pistons and heads/combustion chambers are more or less the same design as 308's so what works on one should translate tot he other?.

Went in one BBI with higher lift cans and new pistons, motor was still new so no full revs used but midrange felt SBC strong. is it true that with the cis you cant have overlap but lift can be added as much as there is space before interfereance with the casting

One thing I dlislike on a BBI, by a little over 6k rpm the magic is pretty much gone, I drove a carbed koning 512 and it was very very different, loved the revs.

Theres a significant on road driving difference between what some narrow powerband motors with high peak hp feel like and the experience with other motors with less peak hp but which make their power over wide rev range.

Currently I run 100 octane unleaded because the motor seems to hate alcohol fuel. Its also true that sometimes one needs to fill up at a regular gas station to get home. But we hear that in future octane ratings will be increased to enhance fuel economy.

In any event it seems like a stock BBi really is 340hp then it should be possible with head work, cams and pistons to get near a real 380-400hp? More to the point, even if its "only" 360-370 hp can the motor be made to build and sustain power up to 7k rpm with cams and pistons, cause that would be transformative.
How far do you think one could go with comp ratio on 93 gas, or 100 octane race gas or a mix. On SBF ford with modern heads 10.4 seems to be the number for 93.

 

3.5~4L displacement, 348 heads if possible, 328 if not. ITB or custom manifold or something with a much larger TB. Stock TB can't make 400HP NA.
CR 10~11.... 10.5 should be fine.
Cams.... This is going to sound odd but check the grind profile of the 275 gtb..
.348"
268°
116° centerline
Or
.375"
260°
110° centerline

After hrs of cam profile designing..etc... I went to our cam grinder and they said... Hey that's nearly identical to the Ferrari 275 .... Hahahahaha... Oh well. It's not crazy lift, lots of duration.. QV has a limiting factor of bucket surface area and you'll have to go with shim under. Hence why I wanted the 348 heads, better valve angles and ports.

 

Oh, sorry about the hijack mark....
Back to regular programming....

 

Thanks Scott, I'll put it all into the mix

 

what lift are those durations at? 1mm?.050"? I'm way down at [email protected], my seat to seat number is right there though at 273.

Years ago the cams in my H-D race bike engine were [email protected], long duration like high compression, that engine was 12.5 and very snappy but with stock 9 (iirc) it was not so snappy....all that overlap caused low cylinder pressure particularly at lower rpm, I'd think 10:1 min for the 260 cams (assuming @050") and 11 on the 268 cams.

 

Ok, I was kicking out ballpark 308 hp increases...for a 5liter instead of 3 liter you'd get 66%more. Cams, compression, flow work a 20-25% gain should be possible IMO. If I were designing it I'd suggest shim underbucket so you can use cams with decent lift while still keeping duration in the CIS happy place....short. Getting it to breathe is the key to making it up to higher rpm so anything you can do here will move you closer to where you want to be. Removing the CIS would help the most and let you have exactly what you're after....its just awful.

Compression. My engine is 10.7CR and I fully expect it will run on 93....I might be wrong, it'll be close but I will probably have higher cylinder pressures that you will so sure, 10.5-11 sounds right to me for you're application. The smaller the bore the higher CR it will tolerate, SBF is 4"? you're 3.188? so you can expect more CR to be fine. but also as I said, the shorter duration the cams the less compression it will tolerate just keep that in mind knowing CIS cams are very low duration

 

no worries, I'm playing with very boring electronics and ECU programming at the moment so filling with something more interesting is good. I kind of chuckled at how many of Nick's engine specs are also FrankenFerrari specs, great minds think alike I guess

 

thank you again for the response.
Keeping the cis which I agree is awefull keeps the car Otherwise “stock” hopefully the changes make it wake up. It’s an old car so not tying to make it compete with a modern rather getting rid of its major drawbacks which on the motor front are a decent Feeling midrange that then falls flat just when you’re expecting it to keep charging.

the other change was getting rid of the trx and going for still high profile 17 In Rims. Transforms the car.

brakes for the road are fine and suspension is fine too, maybe it could use some more roll bar.

 

I've converted 1/2 dozen 308 CIS intakes to EFI....they still look mostly stock and Scott (NFF) can probably do you a bolt-on conversion....something to think about.

Another option is I have a contact, I'll need to dig it up, for a guy who has an electronic control setup for CIS....yes try this

http://www.frankencis.com/frankencis/
[email protected]

This might be the answer a few of you guys are seeking.
We exchanged a bunch of emails about 5 years ago he was using a megasquirt HW based thing, looking to try the o5e HW I was involved wit,h then I think he converted to enginelab.net as I have.....no looks like its still MS based, but that's fine for something like this. With FrankenCIS you keep the CIS but you tune/control it with a modified ECU and my understanding was the mechanical mass flow (which is what limits cams) is no longer a concern.

 

May have shared the wrong he.....noticed this at the bottom:

FrankenCIS is distributed by

Dkubus Pty Ltd

for enquiries about the system please email

[email protected]

I've not used it so I'm not saying anything good or bad but the guy I spoke to seemed to know what he's doing.

 

Let's see...
.020" 268°
.040" 252°
.050" 247°
.100" 222°
.150" 197°
.200" 169°
.300" 96°

You're right on more compression, our engines are 11.5:1 up to 13.5:1 with lots of thermal coatings, ring glands, skirts, tops etc...

11.5~12 would be extra crisp NA with those cam specs.

On the engine above with the money trumpets, overlap is 41.6° with 277° duration @ .01" and 116° centerline. .348" lift. 12.5CR

Another similar build but not with ITB and running 13.8:1 CR... Ethanol build.
46° overlap, 284° duration, same .348" lift 116.5° centerline.

The cam profiles are not peaky at all.. Big nose. Downside is idle sits around 1300, if that's a downside. Revs like it's just done a line of coke at the club.

 

Car is happier with higher idle always.

Ferrai when doing BBIs didnt know whether they wanted to be lux Gt or sportscars, so fell between two stools.
Since a BB is clearly not lux Gts by todays standards, it is desireable to move them towards being more of a sportscar and unlockign the underlayign potential. An example is the heavy flywheel supposedly to aid pulling away from a stoplight. Light flywheel and centerforce clutch makes the motor far more snappy and the clutch modulation easier.
Im not a huge resto mod fan but have nothing against sympathetic upgrading which keeps the essential charter just makes the car more of what its supposed to be.
BBI's because they were in that weird period of emissions and tire tech have some undeveloped bodges, tires and CIS/cams/compression being the prime culprits.

Easy enough to change without really altering the underlaying car, and you get somehting like a 288 as a result, or what the car was supposed to be had Ferrai developed it futher as say lambo did with the CT.

A BBLM outperfoms a F40 on track, so theres lots of potetial in the BB platform once you get past the period roadblocks. The Key imo is to keep it stock looking and with the correct period feel.

 

Got a call from a shop in Florida, customer has a 330 GTC.. wants to update to EFI and oddly drop in an automatic. Original owner, older looking for more of a daily easy driver. They want me to look at adapting EFI to it.. interesting project. Carbs to EFI.. on a classic/vintage V12..
The manifold is going to be tricky... Very limited space... Sounds like a right PITA,.. right Mark

Haven't said yes yet... Mulling it over...

12cyl ECU biggest hurdle..

 

Ok, I thought you were talking 050" numbers...the H-D was [email protected], so another 25 degrees.

We're not that different at the lower lifts...intakes nearly match up to 100 lift, but at 300 I put 45 degrees on you. I have a bit more in the duration on the exhaust...I couldn't quite get the flow where I wanted it so a little duration to make up. TBs almost the same I think mine are 54 vs your 52.
lift Int Exh
.020" 268 275
.040" 252 258
.050" 246 251
.100" 224 223
.150" 205 200
.200" 185 177
.300" 141 127
.350" 114 95
.400" 81 47

Plenty close enough for drivability and such to act about the same which I have to say makes me surprise by your headers. On my engine the best hp has a 6-1 6 step header, second and not far behind was a 6-1 2" iirc, but both were causing a crazy dip (like 80ft-lb dip, it was big) around 3500-4000 on the sim graphs that the 6-2-1 fixed...at the cost of 40-50hp up top so that is what I built figuring its a street car that drives at 3500rpm.

Can you share the actual dyno graph from that engine?

 

there are direct weber replacement TBs so just bolt them on no? Its not about hp its about drivability so no need to get crazy. If the 330 bolt pattern is the same as 400 you can get all the trans adapter stuff at a salvage yard from a 400A and that's a bolt-on clearing the firewall/tunnel would be the concern.

ECU, I like what I have, enginelab EL129(I actually have AEM HW running the engienlab SW but same), thought its only got 10 spark so I'm stuck with waste spark unless I get them to do some custom FW....if there was a second request.....I can give you the model (program) I wrote

Or give it a motec M150 or a pair of ecus....not sure what other options are out there.