302 upgrades

7173Mustangs.com

Help Support 7173Mustangs.com:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

73basicstang

Member
Joined
Feb 2, 2019
Messages
14
Reaction score
0
Location
Oregon
My Car
1973 302 Convertible basic
Do to unexpected problems on my 1986 302 ho I have to rebuild the motor. So now seem to be a good time to do some needed up grades. Here are the spec’s.

1986 302 HO Engine with C4 trans 8” 3.00 rear gear.

Pistons 273AP .030    01511-14-C

Intake Edelbrock Performer 2020

 Carb  Edelbrock 1406

Heads E6SE / stock cam

It will be in a 73 convertible. Mostly street, I will be driving freeways on occasion for car shows. I am looking at 300 to 350HP. This setup is on a budget so keep that in mind. I am looking for advice on weather this is a good fit for what I am trying to achieve.  

OK here are the components I am looking at to upgrade my 302. Spent 2hrs on phone with a technician to make sure everything will work with my setup. 

COMP Cams Magnum Hydraulic Roller Cam CL35-420-8

Duration 270/270, Lift .533/.533 Lobe 110, 1,800-5,000

 

PROMAXX Performance Maxx Series Cylinder Heads 9175

180cc Intake Runner, 60cc Chamber

 

COMP Cams Ultra Pro Magnum Rocker Arms 1631-16

1.6 Ratio, Fits 3/8 in. Stud




 
Don’t use comp cams hydraulic roller lifters. They are absolute junk. I had multiple failures with them. Lots of info about the failures on the internet if you do a search.

 
Do to unexpected problems on my 1986 302 ho I have to rebuild the motor. So now seem to be a good time to do some needed up grades. Here are the spec’s.

1986 302 HO Engine with C4 trans 8” 3.00 rear gear.

Pistons 273AP .030    01511-14-C

Intake Edelbrock Performer 2020

 Carb  Edelbrock 1406

Heads E6SE / stock cam

It will be in a 73 convertible. Mostly street, I will be driving freeways on occasion for car shows. I am looking at 300 to 350HP. This setup is on a budget so keep that in mind. I am looking for advice on weather this is a good fit for what I am trying to achieve.  

OK here are the components I am looking at to upgrade my 302. Spent 2hrs on phone with a technician to make sure everything will work with my setup. 

COMP Cams Magnum Hydraulic Roller Cam CL35-420-8

Duration 270/270, Lift .533/.533 Lobe 110, 1,800-5,000

 

PROMAXX Performance Maxx Series Cylinder Heads 9175

180cc Intake Runner, 60cc Chamber

 

COMP Cams Ultra Pro Magnum Rocker Arms 1631-16

1.6 Ratio, Fits 3/8 in. Stud


 
I had a similar setup as you and I added a 2300rpm torque converter and was glad I did.

Later I added 380 gears and an aod. Even better.

Btw, AFR has new Enforcer 180 heads for a similar specs but likely better components. Similar price

 
I had a similar setup as you and I added a 2300rpm torque converter and was glad I did.

Later I added 380 gears and an aod. Even better.

Btw, AFR has new Enforcer 180 heads for a similar specs but likely better components. Similar price
The AOD and torque is in future. Will look into AFR thanks So what HP were you at?

 
Last edited by a moderator:
Don’t use comp cams hydraulic roller lifters. They are absolute junk. I had multiple failures with them.  Lots of info about the failures on the internet if you do a search.
 Thanks for the info will do more research.

 
My engine is an 89 based crate engine with ported e7 heads. It's supposed to be 300hp

With your recipe I would think 350hp would be about right or maybe more. My plan is to upgrade to afr165

Heads at some point. Make sure your piston valve reliefs match your intake valves, the ones you are looking at have 2.02 which is much bigger than the e6 valves, btw Flowtech Induct

Lists those afr enforcer heads I mentioned

 
My engine is an 89 based crate engine with ported e7 heads.  It's supposed to be 300hp

With your recipe I would think 350hp would be about right or maybe more.  My plan is to upgrade to afr165

Heads at some point.  Make sure your piston valve reliefs match your intake valves, the ones you are looking at have 2.02 which is much bigger than the e6 valves, btw Flowtech Induct

Lists those afr enforcer heads I mentioned
Thanks for the info. Will be doing the clay test for clearance. and checking the push rods for proper length. Thankfully I have a good friend that is an engine builder but he does Chevy engines. Try not to hold that against him LOL.

 
You'll be able to make a little more compression with pistons with 2 valve reliefs instead of 4. I used a set of DSS 8720-4030 in a similar build and I'm really happy with them. They're a really good deal as far as forged pistons go and will give you more freedom down the road if you decide to add more power.

And definitely +1 on checking the piston to valve clearance.

 
The 180 CC runner volume is a bit much for what you are building. Something in the 160-165 CC range will provide more torque in the RPM range you will be using. The AFR street head would be a good option. For pistons and rings contact Race-Tee/Auto-Tec pistons, ask to speak with Randy. You will get a better piston and superior ring package. The performer intake might be OK if you don't want to rev much past 5000RPM. If you want more RPM look at the RPM or RPM Air Gap intake. As for the cam and valve train components, I suggest you contact Brent Lykins at Lykins Motorsports. He will provide a quasi-custom cam for very little extra money. He Also can also provide a better carb recommendation like a Quick Fuel 650 vacuum secondary carb. Check for proper valve train geometry, and order custom length pushrods. Have the deck height checked and keep the top of the piston no more than .010 down the bore at TDC to increase power and lessen the chance of detonation. Good luck with the build. Chuck

 
My first thought, since you aren't working with the original engine, is to get a GT40P 5.0L out of a 99-01 Explorer/Mountaineer. A cam and valvespring upgrade makes them hit 300hp easy-peasy. A 100K mile engine runs around $500 or so, depending upon your locale, and will easily last to 200k.

http://www.car-part.com/

 
The 180 CC runner volume is a bit much for what you are building. Something in the 160-165 CC range will provide more torque in the RPM range you will be using. The AFR street head would be a good option. For pistons and rings contact Race-Tee/Auto-Tec pistons, ask to speak with Randy. You will get a better piston and superior ring package. The performer intake might be OK if you don't want to rev much past 5000RPM. If you want more RPM look at the RPM or RPM Air Gap intake. As for the cam and valve train components, I suggest you contact Brent Lykins at Lykins Motorsports. He will provide a quasi-custom cam for very little extra money. He Also can also provide a better carb recommendation like a Quick Fuel 650 vacuum secondary carb. Check for proper valve train geometry, and order custom length pushrods. Have the deck height checked and keep the top of the piston no more than .010 down the bore at TDC to increase power and lessen the chance of detonation. Good luck with the build. Chuck
Thank you for the info. This setup was recommended by Summit for a nice street and freeway driving that will work with flat top pistons. The build is on 2k budget, this is what they came up with. It should have good midrange to high rpm HP. I am thinking it might be a little sluggish off the line but should have good pickup from there am I thinking wrong? With the C4 and 3.00 gears should help with the low end but can bump up to 3.5 or 3.7 gears if I need to. If I go any higher it will not work well for freeways. I know need a AOD but found out after I had the C4 rebuilt with stage 2 shift kit. Again thank you for the info as I am still learning.

 
I must have missed the $2000.00 budget part. Hemi's post about a take out GT 40P headed engine is not a bad idea. If you do that make sure you get the factory headers with the engine. The spark plug angle on the P heads is different and with conventional 302 headers changing spark plugs is almost impossible without pulling the headers. I don't know if the P headers will work in a 71-73 chassis. Try searching for a used intake that hasn't been cut to save some money. The Summit 650 VS carb is a good carb at a reasonable price. Basically rebuilding the engine and doing the upgrades you mentioned will not come in at the $2K amount in my opinion. Chuck

 
Ok, well I ordered these parts, I should be in the 300 to 350hp range.

COMP Cams Magnum Hydraulic Roller Cam CL35-420-8

Duration 270/270, Lift .533/.533 Lobe 110, 1,800-5,000

PROMAXX Performance Maxx Series Cylinder Heads 9175

180cc Intake Runner, 60cc Chamber

COMP Cams Ultra Pro Magnum Rocker Arms 1631-16

Hedman Street Headers 88400

along with the intake and carb I already have.

Intake Edelbrock Performer 2020

Carb Edelbrock 1406

I will keep you informed on how it turns out. I will dyno test as soon as I get the chance. Thank you all for your replies.

 
Unfortunately, that sort of thing has become common. He did listen to the Summit Racing "tech" though.

 
WOW, sorry if I bruised some egos. I did my homework and read on other forums about the parts I was looking at. I read all the comments and did look at the different options that you and others presented. Yes after talking to Summit tech several times I went with what I feel is a good combination for my car. I have to assume they know what they are doing. This could be a great combo and performs as I hope or it could be total crap. Time will tell. I hope to have the engine built and back in the car by the end of the month. Once in and have a chance, I hope to get on a dyno. I will share the data as it might help someone in the future. Thank you every one for your advice it was helpful.

 
It has nothing to do with egos. It has to do with people going out of their way to try to help you. There are folks on this site that have a lifetime of experience working on cars and building engines and you preferred to take the advice of someone reading stuff off a computer screen when their primary job is to sell parts that Summit sells.

Good luck on your build, I, for one, likely won't offer any help if things don't work out.

 
Back
Top