I got the itch to do a little upgrading on my 350/270hp sbc. I was looking thru summit racing and saw some of these "All in one top end kits". Anyone purchase a kit like this? They say it takes all the guess work out of matching cam to heads and intake ect. All the lift, and duration and c.c.'s confuse the $hit out of me. I really should do more research on that topic, but right now I just want your thoughts on some of these kits, or experiences.

Heres the link to what i was looking at:
http://www.summitracing.com/search/D...?Ns=Rank%7cAsc

I just ran across it and was wondering if anyone has purchased something like this. I want to eventually pull the motor out but a job like this is much less time consuming and $ consuming then pulling it out right now.

 

Looks like some good packages there. I would stay away from the Edlebrock personally because of the cams they use. I and many others don't like their cams.

Also if they are talking about 350ci motors anything over about 400HP and you are going to run into "streetability" problems. There is one there that says 500HP but it could be a real pain in the **** to drive around on the street. Sure you could make more than 500HP but no fun on the street only the track

 

I dont want/need 500hp. Just want to liven the vette up a bit. I'd be happy anywhere over the 325rwhp range. Also the 270 block is a 2bolt correct? 500 and a stock block is a recipe for disASSter no?? I want streetability, just want it flowing better. I want to get a nice idle without vaccuum problems. I dont mind tinkering under the hood but i dont want to live under their either.

 

you have 350ci/270hp ... it has low compression dished pistons.

most top end kits make their performance claims based on a resultant compression ratio of about 10:1.

A 350 w/ typical aftermarket 64cc heads requires flattop pistons to achieve 10:1. You don't have flattops, yours are dished.

Too much cam with too little compression results in an expensive sluggish disappointment.

Study up & pick your bits ala carte.

 

yea i know that i should have done more research but i had the itch and started getting ahead of myself. So your thoughts are hold off until I am ready to do it all? I was also considering getting a used 4bolt and building that up. Then just swapping them out leaving the numbers matching engine laid up

 

there's a plan. look for a later core that has a roller cam. G'Luck!

 

Nothing wrong with a 2 bolt main for what figures your after ( spend the new block money on quality components ),forged pistons , stud the bottom end , high strength fastners etc....and a good balance job will keep it together too

I got 3/8" rods in my 2 bolt 454 with stock factory crank ,used all ARP fastners and bolts....several seasons on it with up to 22# boost @ 6500 and its still together

 

yea i hear on the fact that two bolts do hold power. your set up sounds pretty impressive though.. 22#!!!!! but if im going to do the bottom end i can surely find a used 350 core to build off of. and it would save me down time by just swapping the motors when its finished. honestly i hate how there are so many options! its hard to choose a setup when u have a million parts to choose from.

 

I'm not a big fan of laying up an original motor just to take up space in the garage and give it away when you sell the car. Let the buyer get his own spare motor.

If you have a good motor, buy some quality parts and build it up right.

Give Summit a call and they will help you select the right parts for your application.

 

Your avatar is a picture of an engine just sitting in the garage!!!! hahaha just kidding. Thats my whole dilema really, which way to go. Do I:

1) Find a block an build it up?

2) Rebuild stock motor and keep it Original?

3) Take stock motor and put a stroker kit in it?

So many decisions and Im so up in the air. I dont need to make my decision today but I'd like to at least come up with a plan of attack in the near future. People always ask " whats Your Price range??" then they answer accordingly. My price range is unknown. My feelings are I'd rather spend 6grand over time building it rather then shelling it all out at once. I dont know why but it always felt better to me doing things that way.

Maybe I'll get a block and make a grill out of the old engine, hahaha. Has anyone seen that commercial for the BBQ grill thats a small block replica?? Pretty badass

 

You haven't mentioned your budget or your goals? We have many serious engine builders on this forum. If you did the research, you could build a sb w/cookbook approach.
Do you have manual or auto trans, what are you running for rear gears?
What rpm do you cruise at? How often do you intend to wind it to redline?
Where do you want the power increase, low/mid or top end?
Once you have answered these questions, it is just a matter of who will do the work.
Hopefully you will get what you pay for! JMHO

R

 

I think that I may have let this post get a little off topic. I was more interested in just freshening up the top end. I was just doing some browsing thru summit and stumbled upon the top end packages. After being told the pistons weren't going to give me the compression I need to get the motor running right with some of the things I was looking at, I let the thread wander. My intent was not to get the "how much do you want to spend" replies. I really just let my eagerness get the best of me while looking at summits website. And honestly I want to spend as little as possible, like anyone else that I know.
I make a decent living I feel for a 25y/o, but I also have a newborn, a mortgage, and three other vehicles. So its kind of hard for me to put a dollar amount on what I "want" to spend. Thats why I was looking around at these kits. I figure if I could buy a top end package and just put it on my stock block "for now" that would be a good start, and something that I could build off of later. Also I know a top end kit would be much less time consuming then pulling the motor and having all the work done to it. Im sure all of you have been through this before, but I'm new to father hood and homeownership. So between working 12 hour shift work, being a father, and trying to finish up all the work on my home I dont have too many hours left in the day.

 

I went with the Trick flow kit and got excellent results.I went with there smaller 350hp kit.You can see my dyno and track times in my pics.I put down about 275hp to the wheels.On the higher horsepower kits in order to achieve the stated hp you need some of these items:zero decked block,flat top pistons,or its going on a stroker motor.My engine is a L82 so it was a good choice for a upper end kit.

 

If you want low cost, good generic top end combo solution for dished/L48:

get yourself a pair of good used or new L98 corvette heads (same as ZZ4 heads GM p/n 12556463), 2 head gaskets GM p/n 10105117 and a summit house brand cam & lifter kit sum-K1103.

L98-ZZ4 heads are aluminum, fit conventional intake manifolds & have 58cc chambers. While they're not race heads, they have a proven history of durability & reliability ... new pairs usually on fleabay under $900/pr.

K1103 cam about 442/465 vlift & about 214/224 dur @ .050 ... kit about $90

versus OE 270hp @ flywheel, above should make about 325-335 hp AT FLYWHEEL w/ about 9.7:1 scr

-add-
I'm not connected to it in any way, but here one that's worth following & includes new ZZ4 heads, rockers & headbolts item 200424469870
http://cgi.ebay.com/ebaymotors/ZZ4-C...42110004r18537

 

If you don't want to tear the bottom end down the L98 heads are not a bad option. the casting number is 10088113. Here is a new set. There are a lot of options on cam and lifter sets. The summit set is in the ballpark.

 

Jackson great info thank you.

 

That's a good plan, if that doesn't work look for some vortec heads and intake.

 

I would second a vortec package from summit
http //www.summitracing.com/parts/CMB-08-0034/KitComboContents/
Or you could source parts from other vendors like competition products, cnc motorsports, jegs, speedway motors, etc...... to get the best deal. I got a carb from summit $30 cheaper because they beat competitor pricing on regular stocked items, and for whatever reason this item was cheap at competition products. Piecing something together can get you better parts for close to equal cash outlay, you just have to do more leg work.

 

One good thing to remember is this-the miles makes a difference on what happens. My dad was a life long mechanic and a good one. One of the first things he told me was when you seal up the top side be aware that if the lower side has miles or is the least bit weak then the upper compression you seal off will try to go down. If the rings and/or wear is there then oil consumption and possibly crankcase pressure build will occur. You didn't say how many miles you have. You might want to run a wet/dry compression test to see what you have.

Good luck with what ever you do.

 

Your father seems like a wise man . I have never thought of it in that sense but he is right on. That is great advice.