: rambling about intake - and porting/mod worklog



fubar569
04-12-07, 08:49 PM
first thoughts:

wow...gunk everywhere...needs cleaned...PCV issues and god knows what from previous owner but black shit is everywhere...

method of attack:

at least 18" of rotary extensions on suggestion from eldorado1, plus cutting bits, sanding barrels, and dremel with assocated tools for runner work

disassembly of TB/spacer:

cakewalk - got my core for boring :)

starting hellwalk:

now

fubar569
04-13-07, 11:44 PM
one bank is about 75% done - i still have one side in each runner to recontour...the dremel only lets me get in about 1-2"...so basically all im doing so far is cleaning up the ports...smoothing out the irregularities, and "unshrouding" the injectors. they sit in a hole that is boxed on 3 sides...what i did was cut the 2 edges down and slope them evenly...

i have yet to modify my 18" worth of rotary extensions, but once i do i will be able to reach in a fair bit further, and also start shortening the runners. i plan to shorten them by about 2" (somewhere in there) per cylinder (all equal of course) - this should open up the plenum a bit more, and allow for a bit more upper RPM power with the shorter runner...

eldorado1
04-14-07, 10:20 AM
You can trim about 2-3" off the runners from the inside of the intake. However you're left with sharp edges instead of smooth radiused edges. I really do think the ultimate solution is to build a custom intake from scratch. :p

Also take a look a the intake gaskets. On mine it was sticking into the airflow by 1-2mm on all sides on all the ports. It was acting like a restrictor plate.

fubar569
04-14-07, 01:29 PM
You can trim about 2-3" off the runners from the inside of the intake. However you're left with sharp edges instead of smooth radiused edges. I really do think the ultimate solution is to build a custom intake from scratch. :p

Also take a look a the intake gaskets. On mine it was sticking into the airflow by 1-2mm on all sides on all the ports. It was acting like a restrictor plate.


no doubt!! :histeric:

you warned me about how big of a PITA this was...yet i wanted to do it anyway...once mine is done i'm sure i will never touch one again...:thepan:

i'm sure a really elegant solution exists...for sand cars or street rods of course...i really dont think anyone thought someone would get this far into modifying a production cadillac...lol

though i order my gaskets monday. its actually cheaper to go right to GM for this one...should have then in 1-2 days and get them matched up to the runners...

eldorado1
04-14-07, 02:57 PM
careful not to nick the silicone bead

dkozloski
04-14-07, 11:56 PM
I've done quite a bit of port work and a Dremel is a toy. This stuff is a little better particularly the flexible shaft machine. http://www.dumorecorp.com/grinder.htm

fubar569
04-23-07, 08:05 PM
i've started to do the runner trimming, and i'm 25% or so done with the first runner...

eldorado1 is right...next time im making a custom intake...lol....

fubar569
04-23-07, 10:29 PM
bad news...

poked through a runner in one small spot...however an epoxy fix will quickly patch it and i will be good to go!

good news:

picture...showing 2 runners nearing completion and a 3rd one started...so far taking only about an inch or inch and a half give or take per runner...this should open up the plenum a TON even at the short amount im reducing them by...hopefully this nets some nice gains!

http://mysite.verizon.net/fubar569/intake1.JPG

eldorado1
04-23-07, 11:04 PM
See what a PITA it is?

The hardest one to get to is the one on the very end. You can't get to it from either side. BTW, you'll need to remove the flapper valve to get at much of anything. Doesn't look like you have.

fubar569
04-23-07, 11:35 PM
See what a PITA it is?

The hardest one to get to is the one on the very end. You can't get to it from either side. BTW, you'll need to remove the flapper valve to get at much of anything. Doesn't look like you have.

PITA x 5e77e4w476e964e794w6e054 to the nth power....

how does that valve come out of there?

how much do you figure you have gained from your manifold work?

fubar569
05-11-07, 07:48 PM
good news folks, only 2.5 runners left to go to shorten up and then i can move to porting/smoothing them...

i got the manifold pressure valve out without breaking it...amazingly...it makes the job a million times easier...

the plenum is so much larger now (effectively)...it's amazing to see all that open space come out of something so cramped...the runners only had about 3/4 inch space between them...

hopefully i can weasel in a sanding barrel and smooth out some of those jagged edges a tad...make it somewhat smooth for the incoming air...the runners themselves i am unsure how much material i can remove but if this doesnt get me some nice gains i will be seriously PO'ed...

oh and i finished modifying the stock airbox yet again. i enlarged the stock opening (headlight side) from top to bottom, cut a hole in the bottom (have yet to cut the metal underneath) and furter enlarged the hole i made by cutting off the silencer...i can feel the difference from stock most definitely...

fubar569
05-15-07, 08:42 PM
THE RUNNERS ARE DONE!!!

and i only have 2 left to clean up with the dremel...i am not excessively porting the runners, just smoothing everything out about 1-2" in and gasket-matching the intake...

the runners lost about 1.5" of length and this opened up the plenum a TON...hopefully providing the ability for more airflow and a few HP increase. should be nice gains combined with the completely gutted airbox i now have, plus the TB and spacer plate im ordering from RVM this week.

however, i will never EVER do this again, and instead will make a custom intake from scratch (eldorado1 was RIGHT - PITA!)

the exhaust stuff came in today...4 new 180 degree bends...i need about 2-3 more of these plus 2 flex pipes and then i will be good to get my exhaust up and on the car. i will be retaining EGR and as such will have to extend the tube somehow.

airfuel2001
06-23-07, 08:06 PM
Hi Im newby...I have a 97 STS, rebuilt top end-with timeserts milled heads...I wanted to port, but the down time would be too much-10.4 comp. maybe? I have ported my intake at the injector area...( 3 hours on each port, recontouring and removing as much material as possible-the injector O-ring is bairly visible.) I have moded my intake box, radised my throttle body, the EGR tube going into the spacer was crushed and put back. I have a k&n from my mustang I cut down and put in the modded box, on the exhaust side...I have a true 3 in. catback with a OEM 3in. Y from something else and 3in. pipe going into 3in. bassani muffs and exiting the original location. I am pleased with performance but with the wideband its 10.7-8 at max RPM. Im curious about your shortened runners you and Eldo have done...what did you gain? was it worth it? on my dyno I hold power from 6-6400 more up top would be nice. But I dont want to sacrifice any down low, Im playing with new ideas about more intake...well Im glad to hear that other guys think outside the box, Im new to the N* its definitly different from my mustang....

fubar569
06-23-07, 08:33 PM
Hi Im newby...I have a 97 STS, rebuilt top end-with timeserts milled heads...I wanted to port, but the down time would be too much-10.4 comp. maybe? I have ported my intake at the injector area...( 3 hours on each port, recontouring and removing as much material as possible-the injector O-ring is bairly visible.) I have moded my intake box, radised my throttle body, the EGR tube going into the spacer was crushed and put back. I have a k&n from my mustang I cut down and put in the modded box, on the exhaust side...I have a true 3 in. catback with a OEM 3in. Y from something else and 3in. pipe going into 3in. bassani muffs and exiting the original location. I am pleased with performance but with the wideband its 10.7-8 at max RPM. Im curious about your shortened runners you and Eldo have done...what did you gain? was it worth it? on my dyno I hold power from 6-6400 more up top would be nice. But I dont want to sacrifice any down low, Im playing with new ideas about more intake...well Im glad to hear that other guys think outside the box, Im new to the N* its definitly different from my mustang....

it sounds like you truly have a screamer!

i havent installed my intake yet...i recently moved so i lost my workspace. i intend to do more work to the runners before installation...

what you need is some sort of piggyback computer to lean that motor back out...that is PIG FAT RICH!!

airfuel2001
06-24-07, 08:24 PM
Its crazy...Its an L37 300hp motor slightly more comp, blasted heads, free flowing intake path, catback, It also came with 3.73 ratio, granted Im on 20s-but I should have put more down that 226hp. My suspestion is screwed so I had to dyno in second, the curve looks great-but all the power is up top...I have read posts where Eldo1 put down 260ish? and Marks 99sts fresh motor natural, put down 250-thats with exhaust work and intake fluff and buff. My car is a daily driver...gets me from A to B with style, granted its heavy I never go much above 3000 so I need as much available power from idle to 3000. Im scratching my head, I feel my exhaust is too freeflowing...Im playing with backpressure right now and might have to change something. I put a plug in the one side as an experiment-with it being more restrictive it felt to me I have more torque, it feels decent though, but I would get my **s handed to me by a 300hp 05-6 mustang

jadcock
06-25-07, 10:57 AM
Your L37 has a 3.71:1 final drive. And the 20s are probably killing your acceleration. That's a lot of rotational mass to, well, rotate.

airfuel2001
06-25-07, 11:31 PM
sorry, Im still new at this...Im used to my mustang and the like. does anybody know the ratios for the transmission?

jadcock
06-26-07, 06:42 AM
1st: 2.96:1
2nd: 1.63:1
3rd: 1.00:1
4th: 0.68:1
Rev: 2.13:1

Final drive: 3.71:1 for the L37 and 3.11:1 for the LD8

http://en.wikipedia.org/wiki/GM_4T80_transmission

eldorado1
06-26-07, 09:49 AM
Its crazy...Its an L37 300hp motor slightly more comp, blasted heads, free flowing intake path, catback, It also came with 3.73 ratio, granted Im on 20s-but I should have put more down that 226hp. My suspestion is screwed so I had to dyno in second, the curve looks great-but all the power is up top...

20" rims will kill your hp. Lower gears will have more acceleration, which means the big wheels will take more power away.

There are "mobile" dynos sometimes at car shows that bolt their dyno straight to your hubs (wheels removed). Might want to check that out if you're interested in the "gains" from running on smaller wheels. ;)

airfuel2001
06-29-07, 11:05 PM
Eldo, Im glad I got your attention, I understand you have one of the highest hp N* on here...how did you get there? Im curious on how a 80mm throttle will give you more, when my 75mm will support 378 rwhp on a 7000 331ci motor? Im usually hush hush about what I do and let the car speak for itself, I just ordered a 2001 intake in hopes of retrofiting it on my 97, but it would be too much work to make it fit and work properly. The runners are 15% bigger and would do wonders for airflow. I have an idea on a short runner intake-cut the intake in half, hollow out the "belly" of all ridges, smooth all entrances and rivet the top half to the bottom half with attachments, then epoxy all cracks. I have a second intake thats been ported at the injector but I dont want to lose any power anywhere. question-has anyone ever had a 300hp rwhp N* through the factory trans? Is it even possible??

eldorado1
06-30-07, 08:33 AM
Lets see... custom tune, cone air filter, 80mm throttle body, dual 2.5" exhaust through dual cats and dual full size superturbo mufflers. Those were my mods when I went to the dyno.

airfuel2001
06-30-07, 06:23 PM
what did your tune consist of? I would think it would work on my N* where did you get it...

eldorado1
06-30-07, 08:34 PM
I have a stand alone. I can tune with a laptop.

Submariner409
06-30-07, 10:00 PM
:confused: Unless you have a LOT of time and $$$, 300 FWHP from a 280ci engine is darn near impossible, and you could never drive it on the street.......and comparing a 3,900 lb Cadillac to a modern Mustang isn't in the same ballpark.

airfuel2001
06-30-07, 10:01 PM
the landshark isnt my race car, 4000lbs, with no torque and less than optimum trans spacing...I wont go that far, with everything Ive done thus far I was spanked by a muffler and K&N auto ls1. I hit it first with him behind me, one car in between us...he ran me down and put 1.5 cars in front of my bumper with his factory 3.23s I was interested in the potential with designs of the lt5, but I would need boost to match a stock machine, which would require more time and effort than its worth...In my opinion

airfuel2001
07-09-07, 09:15 PM
:confused: Unless you have a LOT of time and $$$, 300 FWHP from a 280ci engine is darn near impossible, and you could never drive it on the street.......and comparing a 3,900 lb Cadillac to a modern Mustang isn't in the same ballpark.

A 32v Ford does it with bolt ons, stock heads, stock cams, stock intake?