mustang wont start after head and cam swap

88foxbody

88foxbody

Active Member
#1
#1
i finally finished my head and cam swap along with several other parts. so i discovered some things abou my engine when i pulled the heads out. a.) the top part of my three head bolts were snapped off >.< a BIG loss in power :nono: and B.) my engine was bored to a 331! :awesomework: so i did my head and cam swap. replaced the stock heads with a set of gt40p's (got them cleaned up, pressure tested and milled) and a TFS 1 cam (using the stock rocker arms from the gt40p heads for now). also replaced the old timing chain with a new one from comp cams since i had to pull the old one anyway. made sure the timing marks lined up. put everything back together. bought arp head studs, torqed them down. then i found out my pushrods were too long when i had a good half inch gap between the heads and the block. i had a flat tapped cam installed originally. went out and bought 6.25in pushrods instead of the 6.75 which were too long. bought some ford racing roller lifters for the new cam too. new gaskets all around. i go to start the car with the engine tdc and the distributor mark pointing to the #1 cylinder.... Nothing. i move the distributor around a little and have it pointing between cyl 6 and 7, thats the spot where i can get it to start and run for 4 seconds then crap out. i stopped trying because now my battery is dead from trying to start it so much. its definitely getting gas and getting spark can it be that cyl 1 is on the driver side since its a rebuilt 302 from jasper engines and might be a different year motor? im getting really frustrated because i need this car running, its my daily driver. any suggestions why this is happening? did i miss a step or do anything wrong??? :confused: thanks in advance
 
G

glopez4433

Well-Known Member
#6
#6
something similar happened to me a few months ago after i did my heads my car just wouldnt start at all so i tried pushing it and popping the clutch and it just started right up.... try compression testing all cylinders and look for numbers between 100 and 150 is acceptable.... but if ur car is manual try pushing it and popping the clutch into 4th gear 1:1 u might need to built compression... put a small squirt of oil into the spark plug holes
 
MaximumRisk

MaximumRisk

NYC Regional Coordinator
#11
#11
If the rockers are too tight you might be holdning a valve open which would, obviously, leads to no compression in the cylinder. so yeah that could be your problem.
 
Jays04mach1

Jays04mach1

Well-Known Member
#12
#12
88foxbody said:
not sure, all i know is the cam the was in the car was some type of aftermarket cam, and the lifters were flat at the bottom
Click to expand...
So your block is or isn't a factory roller block? Did you put the roller lifter retainers back in? What about the Spring steel retainer that holds the retainers in place? I'm almost wondering if your block is a 302 or a 5.0. Easiest way to check is look where the dipstick goes into the engine block. Is it in the block or in the oil pan?
 
dsblk93gt

dsblk93gt

5.0 Moderator
#13
#13
Jays04mach1 said:
So your block is or isn't a factory roller block? Did you put the roller lifter retainers back in? What about the Spring steel retainer that holds the retainers in place? I'm almost wondering if your block is a 302 or a 5.0. Easiest way to check is look where the dipstick goes into the engine block. Is it in the block or in the oil pan?
Click to expand...
Sounds like someone took a non-HO 302 and tossed it in the car to me. If it is a car or truck roller block it would be ok but something is not right.


IF it had a non roller cam....I hope you got all the roller specific stuff and installed it.
 
88foxbody

88foxbody

Active Member
#14
#14
it is an HO bc i would only start if i used the HO firing order and can i be using the wrong rocker arms?? im using the ones that came with the gt40p's
 
Jays04mach1

Jays04mach1

Well-Known Member
#16
#16
So we know the cam has an HO firing order, but you've yet to say whether the block is a factory roller block or not. If you did a roller conversion on a 302, flat tappet block, you would have to use a small base circle cam to get the valvetrain to work correctly. What are the casting numbers on the block?
 
dsblk93gt

dsblk93gt

5.0 Moderator
#17
#17
Yea the TFS cam is a HO firing order but that doesn't tell us much. Does your motor have the lifter setup I posted a pic of??

Those are stock rockers for 78 and newer small blocks 1.6 ratio. Only the Cobra got rollers, and are 1.7.
 
dsblk93gt

dsblk93gt

5.0 Moderator
#18
#18
Jays04mach1 said:
So we know the cam has an HO firing order, but you've yet to say whether the block is a factory roller block or not. If you did a roller conversion on a 302, flat tappet block, you would have to use a small base circle cam to get the valvetrain to work correctly. What are the casting numbers on the block?
Click to expand...
Yea something is REALLY strange here....
 
88foxbody

88foxbody

Active Member
#19
#19
no, that is not the lifter setup that was originally in the car. there were just flat tappet lifters dropped in. the motor is not original. it was a rebuilt motor by jasper engines. i will post pictures up of the rebuild in a few hours to try and help problem solve. i really appreciate all help and advice you guys are giving me. big thumbs up. and sorry if this thread seems newbish. im only 17 lol
 
dsblk93gt

dsblk93gt

5.0 Moderator
#20
#20
That's ok everyone has to start somewhere. Nobody is going to knock you for trying.

What lifters are in the motor now? If it is a roller compatible block it will look like this. The lifter bores will be machined on the top like this

a non-roller will look like this
 
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