I am "thinking" about building a 383. I have allready bought a Miniram II intake, a new set of TFS heads that flow 260cfm out of the box, and a NEW LPE219 cam (I have this if i decide to do head/cam/intake on my stock shortblock). If I decide to go stroker, I will be selling the LPE 219.

Anyways, thats a brief indication of some of the mods i have bought allready.

Big question is, If i decide to go this route, My goal will be too trap 117-119 MPH in the 1/4, now from what i hear u need around 400rwhp to do that, I am not sure if that is true or not. My car is an 88 Vette with the 4+3. I am thinking I will keep in the 3.07's if i go this route, and see what happens. My 3.07's in the 4+3 is like someone with a ZF6 that has 3.45's in the first two gears, so thinking the 3.07's wont be all the bad especially with the added rwtq of a 383. If i have to go with a 3.45 gear in the future that so be it, but changing the rear is alot of work.

Anyways for the guys with 383 Minirams/LT-1/LT-4, would you be able to provide me your engine specs, meaning head flow, cam specs, everything if you could?????

I would really appreciate, It is my understanding that our motors need CR/head flow, and a cam to all match. Those are the big 3 things that have to flow well together sort to speak to make some real good power.


Thanks alot! Hope to see some good 383 combo's in the 375rwhp-425rwhp area, and that trap 117-120. Thanks again! This build has been a long project for me, but the fun part is researching, and i want to do it right the first time, not the second time.

Also this setup has to pass emmissions!

 

You may want to talk to Bowtye8. He ran a 383 in his 85 Vette with ported Edelbrocks, the LPE 219 cam, MiniRam etc. He ran consistent 11.60's @118.

With a similar set up in my 383 TA with auto, I ran 11.70@116.

The only thing about the Trick Flow heads is that they will need more duration on the exhaust side. Both Bowtye8 and I had heads that flowed hight 70 to low 80% intake/exhaust ratio.

Do you have flow numbers from your heads?

www.geocities.com/dzperf

 

Here's some info on my current 383 LT4;

The cam is a hydraulic roller with the following specs;

242/252 duration @.050
.55x/.56x lift with 1.6 rockers
110 LSA

It's one of the largest hydraulic rollers I have seen. I thought about going to a solid roller...but this is my daily-driver car and I didn't want to have to constantly adjust the valves.

The heads and intake were ported by the guy that designed the cam, they have been flowed and he told me the number but I lost the original flow sheet. He has a copy but I've been too busy to contact him to get another copy! The flow was 310-315 CFM @.600 intake and around 235 CFM @.600 exhaust. The runners are HUGE, at least 225cc.

Here's a link to a picture of my intake ports next to a set of stock LT4 (190-195cc) heads;

http://img347.imageshack.us/img347/1471/dcp00136nk.jpg

The guy that did the heads told me that a lot of the power was in the combustion chamber design though. He said they were extremely efficient and they allow me to run 11.5:1 compression on crappy AZ 91 octane gas without and pinging or detonation. We are running 35-36* timing ont he top end.

Here's a link to a pic of the combustion chambers and another to a pic of stock LT4 chambers;

Mine;
http://img214.imageshack.us/img214/7199/dcp00123ol.jpg

Stock LT4;
http://img214.imageshack.us/img214/16/dcp00118kd.jpg

As for peak HP and TQ, here's a link to a scan of the dyno sheet...we actually never reached peak HP as it was still making power at around 7K;

http://jayism.kicks-***.net:8082/Pic...newdyno-rs.JPG

 

Rick.. 434. Keep saving.. Don't take the middle steps.

 

How about putting the parts on that you have, see how you like the 350. You'll know by the time you wear your shortblock out what you'll want in your new motor. I suspect a larger SR cam and more CIwill be in your ride one day. You got a few months of winter, throw them parts on!

 

Keep in mind for your build the LT1 is more then just a differnt intake it is also reverse cooling. The reasonthis is important is the LT1 will typicaly handle about 1-1.5 points higher then a conventional SBC in terms of CR without knock. You can compinsate for this a little with cam selection and squish but just somthing to keep in mind.

 

yes i do have flow #'s for my heads, did u want to see them?

 

i dont think my 4+3 or my wallet would like a 434. i want to drive the car, and i dont want tuning issues. 117 plus mph at the traps is fine with me. if a 434 was the easy, and cost effective, more guys would be building them.

 

If it where me I would take a close look at Corvette0096's combo. He is almost exactly where you want to be. Now he has an A4 so his ET's are going to be a little quicker then the 4+3 numbers but the MPH should be there. Mabey he could give you the rotating assy he used including deck height and piston selection and what his flow numbers and the cc of his heads. Now using that proven 219 combo as a refence point I would call TPIS and see if they have a better cam for the Mini-Ram or if the 219 is still waht they would recomend. I will say starting with a proven combo is a hell of simpler then starting from scratch.

 

o.k. thanks! i just wasnt sure if the 219 would work well with the Miniram.

take care, and thanks for your email.

 

Did I leave you to believe that the 219 wouldn't work well with a MR? What part of what I told you repeatedly don't you believe?

 

i believe you, didnt i tell you i was going to use it for the 350? i know i told u that, why the comments? u got 345rwhp/350rwtq with an A4 and that is good enough for me if i go the same route as you. it was in the 383 i was wondering about hippy when using the 219 with a miniram and a 383.

getting back to the orginal question. anyone else with 383 recipe's that are making good #'s. thanks!

 

you are making unreal power, i know i wont make anything close to that. i dont have that kind of cash right now. 466rwhp! good job man!

 

Fast Burn Heads 262 CFM
MRIII
cam 224/230 .605/.622 lift
complete Hooker header/no cat/aerochamber muffler

I think you'll find that suspension/tire/converter will get you the big gains and with consistantly.

I think the 260 CFM type heads are great on 383's (especially with the SR), But the MR will definitely allow you to take advantage of more cubes (will allow the Tq curve to move lower).

A decent 383 will run <$3K for the bottom end. Tne only difference the extra cost for the 434 block and additional costs for the updated (roller) valve train in the older block.

However, to really take advantage of the 434 you'll need better flowing heads and a much larger cam.

If you're even thinking about the 434 option, then install the MR and the heads. (I'd still opt for a bigger cam with the 224/224 being the smallest for 350). I'd start on all the periphery "might as wells" that go into a "bluit" car. DFI VII 1.75 long tube headers, Cat Back, Hi-power ignition, 1.6 RR on 7/16" studs, etc...

 

not thinking of a 434. i just wanted 2 see some good running 383 LT-1/LT-4 or Miniram and what mods the guys had, and what power they are making.



ZD1, what power are u making?

 

ttt. anyone else with some 383 Miniram combo's?

 

Absolutely correct. No way the 4+3 can handle a 434.

Also, the 434 requires alot of other mods to the Rear, Tranny, Computer, and a Roll Cage (to name just a few items).

Heads\Cam or a 383 is very cost effective.

Vic

 

Did you say it had to pass emissions?

The MR has no EGR provision and you aren't going to be able to go much bigger than the 219.

 

yes it does, but i am not worried about the visual, it will pass that no matter what.

even with a 219 ralph, do u think i will meet my power goals (if i get those heads flowing real nice, and a healthy CR?).........

 

Just a word of advice. I am in the process of building a 383 with SR and 219 cam. I got a Scat crank and rods. I called Lingenfelter and they said the cam would clear. So being a novice and not thinking to check the clearance on it before dropping it in the car because the machine shop was suposed to check it, I found out the hard way the it does not clear. Had to take most of it back apart in the car and send the cam off to be reground to a smaller base circle. Reason I didn't take it completely out and back to the machine shop is I already had the heads on and most everything hooked up and bolted up and it was easier that way. I found it when I was rotating the crank to set the roller rockers. Called Ling. and they said it fit on all their apps, but forgot to mention that they used high dollar rods that were profiled to clear 383 applications. Set me back almost 2 months and a lot agravation on the project.