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Hi. I bought my 86 a few years ago with a blown engine. I am not a real good mechanic so I went to one who was and he installed a new 350 S/B. It's not an L98, just a plain old 350 with aluminum heads and it is pretty much a daily driver.

Although the engine runs fine, it just doesn't give me the thrill a corvette is supposed to do since I really have no HP to speak of. I've decided that I'd like to try and get about 300 to 350 hp out of it. I thought an Edelbrock Performance Power Package was the answer but now I'm not so sure. In fact, I can't even find one that I think would work from idle to 5500 rpm. Most of the 350s I've found are top end kits. It seems the more I learn, the more confused I get.

I know alot of you are good, experienced mechanics and this upgrade would be a simple decision for most of you as far as what to put in. I have no budget. Just would like to get the job done. Whatever it takes. I was wondering if any of you would share some advice as to where to start. I've done all the basic stuff like adding a K&N filter, etc. etc. I'm not looking for a street burner, just enough hp to make it fun again.

Thanks for any thoughts. :D
 

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What alum heads do you have on engine?
Have you got long tube headers and free flowing exhaust?
What rearend ratio?
 

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Discussion Starter #3
What alum heads do you have on engine?
Have you got long tube headers and free flowing exhaust?
What rearend ratio?
Wow. I'm not sure. The original engine invoice shows a 350 2/B S/B assembly. From there, the mechanic's invoice shows R&R engine and rebuild, exhaust valves, valve seal kit, water pump, spark plugs, wires, belt, etc. No mention of heads so I assume they are the original heads out of the blown engine which was an L98. The original engine threw a rod so the heads were good. We also kept the original fuel injectors.

I've got a good exhaust system. Alot of paperwork came with the car including a Borla catalog but I can't find any invoice of where the guy had it installed. But I'm 98% sure it's a Borla. As far as the headers go, I assume they are the stock headers but I'll find out for sure. Nothing has been done to the rear end so it is strictly stock.
 

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If you have the stock auto diff ratio ( 2.59 for economy) just changing that to a 3.07 can give good SOTP feel ( quicker acceleration ) without even touching the engine :thumbsup:
 

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It looks like the invoice indicates you have a 350 2 barrel carb.

The heart and soul of an engine is the cam.

I would suggest a cam swap, intake and exhust upgrade. Let it breath...

Take some pictures of the engine, intake, exhust, the front of the heads.

Give us some more to work with...
 

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It looks like the invoice indicates you have a 350 2 barrel carb.

The heart and soul of an engine is the cam.

I would suggest a cam swap, intake and exhust upgrade. Let it breath...

Take some pictures of the engine, intake, exhust, the front of the heads.

Give us some more to work with...
I agree with the above.

I was thinking 2/b stood for 2 bolt mains, but it could mean 2 barrel carb.

If it was meant for a carb, then a cam swap should definitely be on your list to take advantage of fuel injection.
Before you go out and buy a cam though, you will need to know if the block has roller lifters or if it's an older style flat tappet.
Off the top of my head, I don't know if the older style blocks would accept the newer style aluminum heads, so it may be the correct block.
 

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I don't know if the older style blocks would accept the newer style aluminum heads, so it may be the correct block.
All SBC heads will work any SBC block except LTX ( will bolt up but coolant passages different )

I was thinking 2/b stood for 2 bolt mains
:agree:
Given that he bought a short block
350 2/B S/B assembly to me reads as 350 , 2 bolt main , short block assembly
 

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if you have the TPI setup you dont really need to look for something ment for top end power, ive done alot of research and have heard that a stock tpi system will not see a ton of gains after 4500rpm

you wont see 350hp either without a heads and cam swap.

I would really recommend a full top end kit, save your money till you can get what you want.

just make sure you get heads that work with TPI good and a cam that will work with it as well.
 

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I will assume you have the stock tpi injection setup. I would start by upgrading the intake. TPIS has a couple options, but if you want serious power I would go with the mini ram system from http://www.tpis.com/parts/view/33 . It is a good starting point since your ability to breath is the best place to start. It would be dissapointing to put some great heads and a cam on you engine and have a restrictor plate for an intake.
 

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I would go with the mini ram
For $1250 there are better options
MR is a serious top end intake requiring really good heads and cam to take advantage of the added breathing capability it gives

Also requires good tuner experienced in MR's to get running right
 

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Discussion Starter #12
It looks like the invoice indicates you have a 350 2 barrel carb.

The heart and soul of an engine is the cam.

I would suggest a cam swap, intake and exhust upgrade. Let it breath...

Take some pictures of the engine, intake, exhust, the front of the heads.

Give us some more to work with...
OK. I'll get some photos and post them. I'm also going to try to get over to my mechanic today and ask him a little more about the engine. You're so right on the cam but I don't want to sacrifice a smooth idle so I need to be careful as to what I swap out.
 

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Discussion Starter #13
I agree with the above.

I was thinking 2/b stood for 2 bolt mains, but it could mean 2 barrel carb.

If it was meant for a carb, then a cam swap should definitely be on your list to take advantage of fuel injection.
Before you go out and buy a cam though, you will need to know if the block has roller lifters or if it's an older style flat tappet.
Off the top of my head, I don't know if the older style blocks would accept the newer style aluminum heads, so it may be the correct block.
I thought it was a 4 bolt. I'll check with the mechanic to be sure.
 

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Discussion Starter #14
if you have the TPI setup you dont really need to look for something ment for top end power, ive done alot of research and have heard that a stock tpi system will not see a ton of gains after 4500rpm

you wont see 350hp either without a heads and cam swap.

I would really recommend a full top end kit, save your money till you can get what you want.

just make sure you get heads that work with TPI good and a cam that will work with it as well.
OK. Then maybe the Edelbrock Performance Kit is the right way to go? I'm just not sure which one is the right one. I was originally looking at #2019 http://www.summitracing.com/parts/EDL-2019/ but now I'm not so sure. Then I was looking at a #2088 http://www.edelbrock.com/automotive_new/mc/power_package/tek_chevy.shtml which is for 1986 and earlier but the engine is not 1986 or earlier. Then there's "Generation I, Generation II (LT based) and Generation III and IV (LS based) ... I've just got a measly 350. I'm all for the kit. I just don't know what to buy. On top of all that when I do get it all put together, I'm sure I'll have to get a new chip programmed. I plant to go to PCM for Less so I think I have that all figured out.
 

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which is for 1986 and earlier but the engine is not 1986 or earlier.
Consider anything listed as <'86 suitable for your engine
Before / after '86 refers to the intake bolt angle change that happened on cast iron heads made after '86.
Vette alum heads which you say you have kept reg SBC (< '86 ) pattern
 

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I was originally looking at #2019
Is for a GEN II engine; LT1 or LT4

Then I was looking at a #2088 .
If you are comfortable in spending that sort of $$$ then there are better ways of doing it.
The E-Tec heads are not on everyone's " favorites" list as a perf head .Are also Vortec style heads so require a special intake ($$$) to work with stock TPI injection
 

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Discussion Starter #17
Is for a GEN II engine; LT1 or LT4


If you are comfortable in spending that sort of $$$ then there are better ways of doing it.
The E-Tec heads are not on everyone's " favorites" list as a perf head
That's why I'm here. I'm already making plans to change the diff ratio. And a head and cam swap is definitely coming. Just looking to make the right choices. Like most C4 owners, I've already got more into it than I'll ever get out of it so what the heck, a little more $$$ won't hurt. Might as well have fun. Can't take it with you!
 

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Might as well have fun. Can't take it with you!
Time to get the notepad out.
What do you want from engine ?
How do you intend to use car? DD , weekend cruiser , occasional track car ?
How much you prepared to spend?
Do you want to keep injection? (# 2088 kit you were looking at was for carb )

TPI based hotups are very well documented;these parts = X Hp
You could copy a proven build without guessing what parts will work

First up you need to know exactly what you have at present.
If you are running Vette alum heads at present then you have 58cc head chambers ( and hopefully new short block was matched to those ) which limits your choices as to off the shelf heads unless you change pistons to suit
Most aftermarket heads are 64 cc which would lower your compression
 

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If you are running Vette alum heads at present then you have 58cc head chambers ( and hopefully new short block was matched to those )
You just hit on something else he needs to check with the short block he bought.
What exactly was it intended for and what pistons are in it.
If it's some low compression engine, then even the 58cc heads may not bring it up to spec compression. Low compression could be the cause for lack luster performance.

If you can't get the info, you will have to do a little measuring with a head off. Determine the deck height and cc a piston if there is a dish or depressions in it. Verify the stroke and bore then do the math to determine compression. There is a little more to it like adding the head gasket thickness and cc's for the chamber.

Hopefully you can get all the info on the short block so you don't have to go through the above.
I would measure everything anyway as that's what I consider fun about building engines.
 

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have you considered a entire new crate engine?

from the way you talk it sounds like the motor you used to replace the blown one was whatever you could find in the junkyard for cheep. so maybe what you really need to look into is a entire engine?

350hp can be had for fairly cheep you might want to look into something like a zz4.


That's why I'm here. I'm already making plans to change the diff ratio. And a head and cam swap is definitely coming. Just looking to make the right choices. Like most C4 owners, I've already got more into it than I'll ever get out of it so what the heck, a little more $$$ won't hurt. Might as well have fun. Can't take it with you!
 
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