freshing up my 302 engine

putting new heads intake carb distributer cam and water pump on. adding some HP and dropping some weight. also removing the AC.
 

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Mike Pass

Supporter
I have had these heads on my sbf 302/GTD for several years now and done many miles. I have the Performer RPM intake also. I weighed the alloy heads and the old cast iron heads and the difference is 44lbs. My 302 with this setup did 335hp and 340 lb.ft. torque on the rolling road. With the Holley it does about 20mpg on a long run and 4mpg on the track.....Gulp!
Cheers
Mike
 

Mike Pass

Supporter
I'm not sure what the cam is as I didn't build the engine but it is very mild and will pull from very low revs and runs out of puff over 6,000rpm. Also uses hydraulic lifters. Very street able and docile in traffic.
Cheers
Mike
 
Yeh we doubled checked it to ensure it fit ok. The guy working on it has a 6.99 quarter mile car so he very good . I think I will get a good bang for up grade. I will post more pics when the heads are on later this week.
 
the cam is a 228 duration with 542 lift . with a 202 and 160 valves . we cut into the pistons to make room for the valves as you can see with the pics. also my engine is a 5 L it is a 1988 engine with forged piston. i was told it has a different firing order then the old 302s.
 

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Mike Pass

Supporter
Looking at your pics it looks like you have the Renault clutch. I had the Renault clutch but it kept slipping. When I investigated this issue with Helix Motorsport they told me that the uprated one is only good for 280ft.lbs. torque so no wonder it had issues with slippage. I had to change it for an AP Racing item which has been OK. Hope you don't get this problem with all that new found grunt.
Cheers
Mike
 
Ford firing order(s)

Ford Engines: 5.0L HO, 351W, 351M, 351C, 400:
Rotation: Counter-clockwise
Firing Order: 1-3-7-2-6-5-4-8


Ford Most V8 Engines:
Rotation: Counter-clockwise
Firing Order: 1-5-4-2-6-3-7-8
 
What is the firing order of the engines with cross over headers?

I am not aware of any other firing order other then the two listed in the above post. If its not the 302HO/351 order, then it should be 15426378.

You are upgrading to hardened pushrods, right?
 
Hi Paul,
I do have some concerns I want to point out to be sure you have covered them and you are not ending up in redoing it again.
1) Cutting in your pistons means you are changing the balance of the rotating assembly...are you going to re-balance it ?
2) I see some marks on the valve stems of your new heads...did you checked the rocker geometry on to the stems (having the correct length of pushrods). The roller should stay in the middle during the cycle of going up and down, or at least have a minimum travel in the middle.
3) Did you calculated the new compression ratio ? Your Alu heads will handle more CR however you should know how much you are. For this you need piston cc, heads cc, headgasket thickness, bore size, etc..
 
yes we up graded the pushrods. we pre set the tool so all pistons lost the same weight so I hope that will keep them in balance. they did check the to ensure proper length for the pushrods. I will ask what the new compression ratio is. also I noticed that steel bar that goes from the frame to the motor mount. the engine does seem to sit nice and not move much when under load.
 
Hi Paul,
Those steel bars act as a spring since the are bend under torque. Depending on the thickness, quite a strong spring but not harming to my feeling.
About balancing the engine, you need to know if it is 50oz, 28oz or internal balanced. I think you have 28oz unbalance and I think it needs balancing in that case...but I am not an expert in balancing. Best to gain the right expertise to be sure.
Regards
Andy
 
I would not be to concerned about that minor flycut you have made on inlet eyebrow of pistons, they all 'look' similar and should not have increased any variation across the set by more than a gram or two. The reciprocating portion of the effective bob-weight on your combo will be ~ 800gm's, the amount you have removed will only be about 12/15 gm's max, probably less which is less than 1.75%... as its quite acceptable to 'overbalance' reciprocating weight by a couple of percent for a performance engine you should be OK. The fact that its a 3.00" stroke ( short ) also reduces the concerns, if it was a 4.25" stroker the change would be more critical.
 
Thanks guys. Every time you guys answer or ask a question just shows me that I know nothing. I find it helpful so keep it up. I will post new pics when I get more. I am just fighting with the guy doing the work right now. He is doing my car as filler work and it was not to be done like that.
 
..Seriously, make sure you get new hardened steel pushrods. The guideplates on your new heads will eat your stock ones in short order.
 
I think I shouldn't have told the guy working on my car he's an idiot for not doing my car faster. He is doing it at the end of day extra work and it drives me nuts . I guess they don't value clients that bring them lots of work. I have given him 60,000 in work over the last three years. Well I will be looking for a new guy.
 
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