Max power with stock GT cam?

the metal used in 302 blocks produced in mexico had a higher nickel content I believe so they made the mains wider i believe? Thus its a stronger block then the regular 302.

It was kind of like in this order of stronger blocks. The stock 302, mexican block, and dart block. Dart block still being the much better block but the mexican was still better then our 302's

You are correct, the Mexican blocks are stronger, but are old, and not set up for roller cams. So you have to spend a whole bunch of money converting it to a roller motor to run a stock cam. With the power levels consistent with a basic H/C/I combo, a late model roller block is sufficient, and it is much cheaper to setup.

Kurt
 
You are correct, the Mexican blocks are stronger, but are old, and not set up for roller cams. So you have to spend a whole bunch of money converting it to a roller motor to run a stock cam. With the power levels consistent with a basic H/C/I combo, a late model roller block is sufficient, and it is much cheaper to setup.

Kurt

actually retrofit kits arent really that expensive.

COMP Cams 31-1000 - COMP Cams Retro Fit Hydraulic Roller Lifter Kits - Overview - SummitRacing.com
 
a word of warning about those kits ...

yes, they put in a spider hold down setup like the HR blocks have, and they allow you to use hyd rollers and cam, but the real problem is that the lifter bores are actually shorter than they are in roller blocks. so even though it is now possible to use HR lifters, if the cam lift is high enough you can still stress the spider to where it may not really keep the lifters positioned correctly.

it has everything to do with the height of the lifter bores.

so if one wants to use HR lifters AND go crazy with lift on one of these blocks, one should probably use link bar lifters instead. and those mothers are not cheap.

then there is the small base circle cam option, but that is not recommended by anyone.

at least that is the case with the older non-roller 351 blocks. i am guessing the same holds for the older non-roller 302 blocks?

can someone verify or disprove?
 
I thought I read somewhere that if you did the retrofit kit you were forced to run a small base circle cam. I was under the impression that the only way to throw a standard HR cam in there was to use the link bar lifters.
 
I thought I read somewhere that if you did the retrofit kit you were forced to run a small base circle cam. I was under the impression that the only way to throw a standard HR cam in there was to use the link bar lifters.
My understanding is that it has more to do with the lift of the cam than anything else.

Probably most people who build custom motors want to go with agressive cams that have alot of lift. That is exactly the case where the spider could eventually lose its bounce back and fail to hold the lifters correctly and they could eventually spin and cause a disaster.

In that case, the smaller base circle cam drops the lifters enough to keep them in the bores enough to not be a problem. but then you get more stress on the lifters because of the steeper ramp rates required with a smaller base circle to achieve the same lift as on a larger base circle cam and the fact that there is more unsupported lifter (on the cam side), also because of the smaller base circle.

i actually have a spider hold down conversion and a normal base circle HR cam in mine (a non-roller block), but my cam also does not have enough lift to be a problem. nevertheless, i still worry about it from time to time and would no longer worry (about that at least) if i had dropped the extra $300 for the link bar lifters up front.
 
I also disagree with the post that you have to lose mid-range power to get to 300rwhp. I'll bet you my next pay check that if you told a custom cam grinder that you were adding aluminum heads and a new intake, and want a cam to improve power all through the power band AND have a higher peak he could do it for you. Peak horsepower doesn't move the car, average horse power does, this is why custom cam'd cars go faster, they have more average horsepower. Also why long tube headers are bomb for the street, they add little to nothing over shorties peak but the average horsepower increase is noteable.

Adam

Wise words here from Mr. Adam :nice:
therefore
I'm gonna throw in with him here :)

Yes ... you do have a tendency to loose low end torque when you mod
for more power

Mid range can suffer as well but not like low end

B U T

That don't mean low/mid range will ALWAYS go in the crapper

It is very evident :(
All those hp/tq curves from Dyno Pulls I used to post up :crazy:
Peeps did not look or learn anything from em :nono:

Or else ... Like Adam and I are saying here :D

That was the proof that you can hot rod and not have to give up
low mid range get up and go :banana:

You gotta remember this ;)

These days we got ...............
1 long runner intakes
2 fuel injection
3 roller cams
4 tuning that can optimize a spark curve

A lot of ... general rule of thumbs ... such as ................

Hot Rod up a car and the low end is gonna be non existent

That was true before we had 1, 2 & 3

Now as for #4
All you had to do was pull one spring out of the dizzy ;)
and
Close up the points just a wee bit :spot:

Grady
 
95GT, T5, AFR 165's, FTI Cam, Edel RPM,
30# inj, Mac LT's & Cat Pipe, 373's
Stock TB, Maf, & Catback
Tweecer Tuned
293hp 322tq

Grady, you should easily get over the 300rwhp mark by swapping in a bigger MAF, TB, and higher-flowing catbacks. You might even get over 310, and that's without losing low rev torque. I'm surprised you didn't think of that already.
 
Whereabouts in Oregon are you located?

I live in Cornelius, OR. Are you in Oregon?


This is a very interesting thread I started.....I created a monster. Thanks to everyone for all the advice. One of these days I will get to the engine stuff. Still working on the tranny swap, damn I am slow. Its nice to work on something and just take it easy....no pressure. If I worked this slow at work ...well I won't have a job anymore.
 
Grady, you should easily get over the 300rwhp mark by swapping in a bigger MAF, TB, and higher-flowing catbacks. You might even get over 310, and that's without losing low rev torque. I'm surprised you didn't think of that already.

Well :D

Since you brought it up :)

When I built the combo I wanted to not compromise on certain parts :Word:
You know stuff like h/c/i
So ... money was spent there as opposed to other parts

I knew the small gain items could be replaced later ;)

TB, Meter, and Catback would certainly fall into that category

The OEM meter was just pegging but not by much :(

I did upgrade the tb and meter but have not been to the dyno :bang:

I can say the difference starts to be felt at mid range and gets more
noticable as the rpm's climb :nice:

As for the catback ... I'd bet a gain of like 5 rwhp would be about
the most you could expect

Several years ago I remember a member who I knew was the kind of
fellow who posted up stuff that could be considered to be reliable

He had a full on 347 with all the good stuff to support it

Believe it or not ... He was still running the OEM catback :eek:

HE went to an aftermarket catback and only picked up 10 rwhp

I have always felt if that was all he got

A combo of 50 less cubes will flow less air
therefore
The gain from a catback would have to be less on a smaller motor

anywho ... Just a random thought or two :spot:

Grady
 
Well :D

Since you brought it up :)

When I built the combo I wanted to not compromise on certain parts :Word:
You know stuff like h/c/i
So ... money was spent there as opposed to other parts

I knew the small gain items could be replaced later ;)

TB, Meter, and Catback would certainly fall into that category

The OEM meter was just pegging but not by much :(

I did upgrade the tb and meter but have not been to the dyno :bang:

I can say the difference starts to be felt at mid range and gets more
noticable as the rpm's climb :nice:

As for the catback ... I'd bet a gain of like 5 rwhp would be about
the most you could expect

Several years ago I remember a member who I knew was the kind of
fellow who posted up stuff that could be considered to be reliable

He had a full on 347 with all the good stuff to support it

Believe it or not ... He was still running the OEM catback :eek:

HE went to an aftermarket catback and only picked up 10 rwhp

I have always felt if that was all he got

A combo of 50 less cubes will flow less air
therefore
The gain from a catback would have to be less on a smaller motor

anywho ... Just a random thought or two :spot:

Grady

Don't get rid of the cat back! You will lose ALL OF YOUR LOW END GRUNT! You need the back pressure! You'll have to idle at like 850 RPMS! It will stall at all the red lights, you won't be able to drive the car on the street!

:rolleyes:

Adam
 
I knew the small gain items could be replaced later ;)

TB, Meter, and Catback would certainly fall into that category

As for the catback ... I'd bet a gain of like 5 rwhp would be about
the most you could expect

HE went to an aftermarket catback and only picked up 10 rwhp

Well, 5rwhp here, 5rwhp there. It's those little things that can make the difference between getting over the 1.0rwhp/ci mark (0.9rwhp/ci for an automatic) or staying under it. :D
I think an H/C/I 302 would gain closer to 10rwhp than 5rwhp from catbacks, and if you don't want to part with your existing tailpipes you could just replace the mufflers.
 
Well, 5rwhp here, 5rwhp there. It's those little things that can make the difference between getting over the 1.0rwhp/ci mark (0.9rwhp/ci for an automatic) or staying under it. :D
I think an H/C/I 302 would gain closer to 10rwhp than 5rwhp from catbacks, and if you don't want to part with your existing tailpipes you could just replace the mufflers.

Yes ... I see what you are saying and agree :D

My focus was on making power :Word:

I just wanted to point out that I would put my priority and money toward
items that would do the most good ;)

You see peeps do the bolt on thing and wonder :scratch:
Where is the power :bang:

Nothing wrong with that method :nono:
but
The reality of it is ... not much to be gained doing that :(

Yes ... that method is simple and you can do it piece by piece :nice:
but
I been down that road years ago :)

If you are gonna go for max power :banana:

You gotta upgrade ... ALL ... combo parts

I just wasn't gonna put my money toward a tb which would not give
gain like a set of nice flowing Aluminum heads

A catback before a custom cam

An aftermarket meter before an aftermarket intake

etc ... etc ... etc

That is all I was trying to get across :D

Grady
 
Good point Grady! Another thing to mention is that if you go bolting on this and that over time, you'll keep getting used the little gains in power and each step won't seem to do very much.

If you do the H/C/I all at once, you'll feel a HUGE kick the butt with the amount of power you'll gain... So that's why it's good, if you can afford it, to do the entire combo all at once.