Not pre-ignition, but detonation (knock). They are not the same thing. Fortunately the pent-roof 4 valve head is more detonation resistant than the 2 valve hemi-head. I would be a good idea to use a device this this http://www.jandssafeguard.com/ John from J&S posts over at http://www.efi101.com/forum/
In general higher compression means you can't run as much boost, but that doesn't mean no boost. The limit when the CIS system is used is fuel, the boost is set to as high as the CIS system will supply enough fuel. You should be fine, at worst you'll have to run a couple psi lower boost, but I don't think that will be the case.
FYI, Got a box from Carl today. Modified SC mounting plate, reworked tracking rod and mounting block to test fit and mark up for final dial-in. Also received the machined harmonic damper and reinstalled it with the SC drive pulley. Pics to follow soon. HEY !! the bonnet closes with the supercharger mounted up now !!!! And everything clears the frame etc. by a good 10 or 12mm. Stay tuned for further developments (cold air intake is on it's way ). -Lou
We are only a few parts away from DONE at this moment. Lou should be validating final changes now so I can take away the prototype pieces and replace them with pretty pieces. On the Superchrging of a 9.5 to 1 CR with a single improved wedge combustion chamber - I have done many of them in aluminum just like that on the 2v Porsche 928s. When we supercharge at 6 psi on a K-Jet fuel system there has been no problem. The detonation starts at about 11 psi on those heads.
Well boys, I actually fired up the motor with the Supercharger hooked up tonight (McGiver'd intake system and temped in blow off valve vacuum connection, incomplete belt/tensioner) but........IT WORKS !! It sounds wild (kinda like a really pissed off mountain lion), idles perfect on cold start, revs come up very quick (didn't bring it up much above 3500 til it's all done and on a dyno/fuel air monitor). We are close to getting this done. Once I get the prototype brackets and things I am fabing here back to Carl, along with the confirmed mounting plate, tracking rod and cold air intake etc. he has worked out, it should be a race to the finish. Once I get pretty polished and powder coated parts back I will post a full install scenario with pics. I'm stoked, to say the least !!!!! -Luigi Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login
Michael, Looks like maybe 2 weeks +/- to Supercharger completion (Carl ?), hopefully have it dynoed and dialed in by the next "Big Sunday" . Recieved my sump baffle upgrade from Australia yesterday, I've recieved my QA-1 adj shocks, Eibach springs are due in 5-9, the brake booster/MC rebuild, coolant line replacement, and timing belt/tensioner change out all worked out stunningly. It's coming together, baby (look out Willow Springs, Buttonwillow in June??) I'm rolling un boosted to the C&C Ferrari featured marque (50+ cars) Saturday down in O.C. (BTW, I have your Porterfield stainless brake lines, $85) -Luigi
This thread is awesome. I like the bracket and pulley on your system, Lou. Subscribing to this thread!
It's Carl Fausett's work you are looking at, I am just making modifications and fabricating changes to fit the 308 GTS on my end. Wait until Carl and I get the belt length & tensioner and intake etc. worked out, then you will see the real deal. But thanks for the positive comment. Personaly, I am looking forward to dyno results, 300+ rwhp is definatley a realistic expectation on the QV (208 baseline rwhp + 50% min w/boost). 370+ @ the crank hp in a sexy a$$, ultra low 308GTS, .....oh yeahhhh. Maybe MORE if the dyno fuel air numbers allow us to push the boost up a notch with a smaller SC pulley!!. Hemi type heads on the quattrovalvole motor may bring us happy results in this area in regard to detonation etc. The dynojet will tell us. Ciao, Luigi
Sorry if this is a dumb question but I thought that you couldn't have hemispherical heads on a 4v head? I thought you could only have a 2v? Am I off base with that thinking?
You are correct - the qvs technically have pent roof chambers -- which as Lou correctly says qv heads are efficient in combustion and help prevent detonation.
IT LIVES !!! Update, I am rolling to C&C Ferrari meet in O.C. in the A.M. SUPERCHARGED !! I received and installed the cold air intake prototype from Carl built off my plastic mock up, fits perfect. Worked out the belt tensioner issue, hooked up the cooling fan, and with Carl's blessing, tweeked the K-jet CIS to the rich side to be safe. Took it out for a test run with my wife (scared the sh*t out of her). It's awesome, the front end gets very light @ 5000 rpm in 2nd, and it just pulls from there on up through the gears. I am keeping it under 5000rpm (patience..,grasshopper) until I can get it on the dyno/fuel air, but MAN....it works. It's a rocket. Pics below. I will keep posting progress reports, and ,as I said, post a begining to end install sequence on the completed fit and finish kit. -Luigi Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login
Dude, You are a BAD man! BAD! BAD! You are making me think more and more that I NEED this on a certain blue Mondial.....BAD! 350 HP Mondial prowling the streets of MA waiting to pounce on unsuspecting victims.... I would really love to hear a sound clip of this thing in use, perhaps just from the cockpit. Birdman
Looks excellent. Great work Lou! Can't wait to see the numbers. Rockon! Chris ( with no SuperCharger)
A short accelleration video from early this morning. I have to short shift @ 5000 until we confirm all is well with AF. (might have got a little higher there for a second, really wanted to stay with that 355). -LouGaudio (soon to be BoostedQV) Image Unavailable, Please Login
Truly excellent work!! Surely something to be proud of. Looking forward to the numbers - have fun! Brilliant video!
Carl, chris03053 & I were looking at the installation pix. We noticed something you'll want to check into. The York type compressor used on most 308s before '85 is larger & has a larger mounting bracket than the Sanden type compressor on Lou's car. (See attached pix). The mounting bracket is much more square & extends further up the cam belt cover. You should verify that the coolant line will route around it w/o problems. We think that it will, but best to make sure. Image Unavailable, Please Login Image Unavailable, Please Login
Hmm, to be honest I don't quite know what to make of that. There is some hollow metal sound, where I don't know is it the SC or just ambient camera noise. I didn't hear the "pissed of mountain lion". Also I think you don't have a tubi, right? Not to rain on your parade. I love the project, but I think that video didn't tell me as much as your descriptions and pictures do. BTW: I have mounted a camcorder once on the 308 engine bonnet (outside of course). Gave some great footage, but for the best audio, you need an external microphone routed into the engine compartment (or at least into the trunk).
I thought the same... you can't tell from the video that it's any different than stock. I'm sure you can in person, but the video probably doesn't do it justice...
