ok well I'm running on a limmited budget and im hitting a brick wall with my engine build. I'm doing a 305tbi-350tbi swap in my 92 rs. I want to build a bottom end monster with an effective rpm range to say about 5500-5800. I PLANNED on doing that with the use of a mild cam XE268 and 305 heads and some nice gears. Well got my loan so now its buy me time and well all hell is breaking loose. I realized all the threads about saying use the tpi 305 heads not the tbi 1s, am I right in saying the 416's are tpi? Is this cam what i need or am I completely wrong here again too. the only thing i have for my engine already is every thing from the deck down(no heads-up) and no cam. I dont know where to look on my heads to see their casting numbers but from what i hear everyone says 305 tbi heads suck. Sorry for the extremely long post but I do't have alot to go with for cash, i can come up with about $600 more maybe $700 and thats about it. HELP PLEASE



P.S. I know i can pick up a newly rebuilt set of 416 heads that have been thermaly cleaned, magnafluxed , 3 angle competition valve grind, ported to 63cc, 1.84 int "high output valves " these heads for about $240 total

 

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I'm using an XE274 and a set of 601 heads (very similar to 416) on my 350 and it works great! The only mods to the heads are cut down valve guides to handle the extra lift, and 1.94/1.5 valves.... I did screw-in studs and guildeplates too, but thats not totally necessary, although not a bad idea if you use heavy valve springs.

The XE268 and 416 heads should work quite well together, you'll like that combo.

 

awesome that cuts out some of the delema interesting you used the 274 havent bought cam could you tell me what gains you got with your combo that would exceed my setup?

 

I doubt theres actually much difference between them. The XE274 is only one 'step' up from the XE268 (6* more duration, each side) and the 601 heads give a slightly higher compression ratio, compared to 416 heads (53cc chambers VS 58cc chamber)

My combo has alot of potential for deep 13s, since it runs just a bit over 100mph in the 1/4. I can't get into the 13s yet, but thats a driveline issue... weak rear end, bad gears, no posi, tiny crappy tires, lol.

Anyway, enough of my rambling... the 416/XE268 combo should work really nice on your 350. My only suggestion is getting some 1.94/1.60 valves installed (1.84/1.5 is stock) in them to take advantage of the bigger cam and larger bore of the 350.

 

well i found out i have the crappy swirl port 180's i think so i bought me a set of 416's for 180 bux(yeah i know not bad) heads been ported polished to 63cc and have the stock size hardened valves with a 3 angle done and magnafluxed basically the works cept 1.94 and 1.6 valves this should be good enough to run me in the low 14'2 high 13's with the shift kit, 3.42 gears, and 8 in wide tires i think five7kid made high 13's with this set up I am just waiting for parts to get here I will post pics of progress soon

 

High 13s are defnitely doable.

 

well since im getting the 416 heads would it be easier to use my uncles performer carb intake or get the tbi one and if i go either way what are the pros and cons? will I have to do any mods besides the adapter plate for the carb intake

 

The Edelbrock manifold is probably better than the GM TBI manifold. If it will not be too tall (with the adapter) I'd suggest using the Performer over the GM manifold. Either intake will work with those heads though, but you may have to grind out some of the bolt holes on the TBI manifold, since that manifold was designed to have the center intake bolts go in at a different angle. Thats an easy fix though.

 

hey well how much taller is the performer carb manifold than the performer tbi 1?

 

the 268 is about where you'd want a higher stall speed.
Those 2.73 granny gears are going to make you hate life as well.

416's weren't TPI heads, 081's were the TPI heads. The 416's were the perimeter bolt 305 carb heads. 1.84" intake valves aren't really considered high perf, i'd use the 1.94's for sure.
See my sig for my setup.

 

im putting 3.42 gears in btw

 

Not true actually... the SBC went to centerbolt valve covers in '87 IIRC, and TPI first appeared in '85. Two years the TPI motor used 416 castings

But anyway... 416 and 081 are the same, except for the valve cover setup.

 

Port your TBI manifold and through the edelbrock one away. If you do not feel like doing it I have a ported TBI manifold for sale $150.

Anyways, you are talking about a carb manifold and a tbi manifold... which is it? You carbing or TBI?

I have a ported Edelbrock Performer RPM for sale too at $150... I know it seems as if I am soliciting but I am trying to help.

As for the height, with a decent drop base cleaner you will clear an RPM intake no problem. TBI is no problem either.

 

i am staying with tbi but i have a performer intake for a carb that I could just get an adapter plate for and use my tbi or i have to change the center intake bolts on my stock one but since my uncle gave me the edelbrock I think I'm going that way