Hey there TGO

I pose some questions on my pending 383 build.

My basic question is, with the gobs of torque a 383 will be making, would some extensive porting of the plenum, runners and the base (essentially shortening the effective runner length to help it rev higher and raise the peak torque and hp a little higher in the rpm range) would my 1/4 times benefit from this or would I just lose torque. First off, let me tell you my proposed setup (the pieces I think I know for sure)

350 bored .030, and stroked to 383 (forged crank)
forged pistons and rods
TPiS Big Mouth Base (ported, possibly siamesed)
AS&M Siamesed Runners
Ported stock plenum
AFR 195's (should I go bigger here?)
1.6 rr's
3.73 gears
built 700r4
spohn adj. torque arm
lca reloc. brackets
spohn tubular sfc's
2800 stall TC
some form of drag radial

I still don't quite understand how to choose cam's, so that's up in the air. Any suggestions would help a ton. I'd like to get 400rwhp and upwards of 450rwtq. What could I expect with this setup for 1/4 mile times and trap speeds.

Anyways! Back to my original question. Since this 383 will have plenty of torque, would anyone recommend that I trade some of the torque off for hp by siamesing the runners and the base and extensively porting the plenum? I will have enough problems hooking as it is, I might as well trade some of that torque for some improved upper rpm breathing power.

Any input would be greatly appreciated.. I'm debating what to do at this point. All I have is the 350 block and the TPiS big mouth base.

 

With that combo, your looking at roughtly 320 rwhp after a good tuned and about 460 lb ft tq. 1/4 times would be in the low low 13's and 12's with dr's

A ZZ4 spec cam or a little bit more duration would be awesome for a street cam.

 

hmm. sounds promising. how can I boost that # closer to 400rwhp maybe at the cost of tq if necessary? Possible not if I could help it. Bigger heads? more ported runners/base? I would really like to keep the TPI for now. Superram/miniram is in my future at some point though.

 

Apok,
I will be doing almost the same set-up except that I will go either a LT1 conversion or the mini-ram. I am trying for 10.75 compression and I too think I may go with the AFR195's, then the n2o when it's all done!

Anyone have a hp difference if Apok or myself goes to a 200 or 210 head?

I think you are limiting yourself with the TPI to make potential hp at 5500rpm.

 

I too believe I am limiting myself with tpi. The only other intake I would consider would be the super-ram.. and I have just heard some bad stories about the install process. My car also has to pass emissions and I have heard that it will not with the SR. All of this is second hand info obviously, but I am definitely open to suggestions.

If a severely modded tpi can't get me well into the 12's, and possible 11's, then I would like to add a supercharger to the mix later on down the road.

Once again.. I am still open to suggestions. What I want out of this car is mid 11's. Somewhere between now and the time I die. I am seriously considering forced induction if I need it to achieve this goal. I was hoping for more than low 13's out of this engine. Anything I can change for now without changing intakes or adding forced induction into the mix to make mid 11's? Or is that impossible and way too much to ask from a modified tpi?

 

A Super Ram will pass smog. Somebody lied to you. It is 50 legal

 

ok fair enough. Can a super-ram be used with a big mouth base? are they in-compatible or does it just make no sense?

For that matter I might as well just ask. Aside from the LTR setup, what other intakes can be mated to the bigmouth base effectively and efficiently (concering time taken to match it, and money issues as well to get them working together)

Since all I have at the moment is the 350 and the big mouth base I'm not too attached to tpi I suppose :P

 

If you used the Lingenfelter 219 cam, along with a SuperRam,(yes, you can use it with the bigmouth), you should have no problem with high 11s. Try not to use the LTR's. My friend, Floorguy has this setup with edelbrock heads, S/R, and runs 11.80s with no intake porting, MAF, and a stock chip, on drag radials. Everything else in your list looks great. You really dont want to go any larger than the 195 heads, unless you want to put a big engine under it. Otherwise your combo seems on the right track, IMO. Maybe you might need a bit more converter, but I would not buy one until you try the one you have now. It might be fine.

 

So you are saying that a 383 and a 195 head are a good combo?

I have read about 350's that use 200 and 210 heads, isn't the 383(more cubes) require bigger heads?

 

Yes, and no. It all depends on the application. If killer airflow was all you were conserned about, go with the 220 heads. A smaller (180- 195) port usually will have more port velocity. Your engine will most likely be operated in the low to mid range on the street, than at WOT. If you were building a dedicated race engine, you would want the larger port heads, but you will loose some of the low to mid grunt. you would most likely be happier with heads in the 180-195 range for even a street/strip engine. You can do a search on the many head types, and take it from there.

 

that's great news that the SR is compatible with the big mouth base. I guess now I should move over to a different board as this topic is no longer consistant with the one we're on. Thankyou very much for your help!

 

Your welcome, glad I can help. Remember one thing. There are many routes you can take, but there are some proven combinations that are hard to beat. Stick with somthing you know that has been successful with other members on the boards. There are many 383s with a S/R and 219 cam that run fast.

 

Concentrate on torque, and H.P will follow.

 

sounds like good advice to me! :P