Technical SBC head/Valve train question

I'm swapping over the 993 heads on my 355 to a set of 186.
Right now I have stock type roller tip rockers with no guide plates.
The 186 heads are machined for screw in studs so I'll need to use guide plates and the pushrod holes appear to be different from the slotted ones on my current heads.

I know you need treated pushrod with guides but can you run the regular roller tip rockers or do I need to change them

Pic of new heads attached

 

No guide plates on those heads . roller tip rockers will work .

 

My studs will bottom out without the guide plates could I use washers?

 

You need guide plates or you will have to run self aligning rockers.
Looks like the push rod holes have been drilled out.

 

I would say if you need to put washers under the studs, then guide plates will be what you need. I would run the guide plates, at high rpm that valvetrain will be all over the place. JMO. Lippy

 

You're right , those holes have been opened up ...

 

Yep!!!!.... I'd be looking for leaks inside the intake ports also....

 

I ran the "186" heads on a 355, good heads(1970 castings).

 

You thinking that they hacked into the intake runner's?
I'll check later

 

Another vote for guide plates. Cheap insurance.
r


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Here are some pics.

 

Yea, at higher rpms, your pushrods will be all over the place.
r


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Yes I'll get guide plates
I can still use my roller tip steel rockers?

 

Do I need to change pushrods?

 

I ummmm... Nevermind! Your in good shape..

 

Hardened steel pushrods and guide plates should do it!...

 

Yes!....

 

They don't look ok?

 

If you use a non hardened pushrod with a steel guideplate, the guideplates will eat the pushrods in a short amount of time, filing them away at the contact area.

You need the guideplates due to the drilled out pushrod holes, you can re-use your roller tip rockers, you need new hardened pushrods for use with guideplates if what you currently have with your roller tipped set-up isn't already a hardened aftermarket pushrod. a file can quickly tell you if they are hard.

 

I meant the heads

 

Go to "alexsparts" on the net he has great prices on adjustable guide plates + pushrods, etc ,save yourself a few bucks ...

 

What style of rocker do you have?

 

Steel stamped type with roller tip

 

Summit brand

 

Are they self aligning rockers or not?

 

Roller tip are not self aligning
r


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Then I need new rockers

 

To answer your question, Your head's are Fine! No worries on intake

 

An no, your roller tips are also fine..
Guide plates an pushrods hardened... An Go

 

No, you don't.

You need guideplates, screw-in studs, and hardened pushrods....then just re-use your roller tipped rockers.
Done.

The guideplates take the place of the once slotted cast-in pushrod guide holes that have been drilled out, and thus keep the non self aligning rockers located correctly,... and the hardened pushrods solve the problem of the hard steel guide not being self lubricating like cast iron was with the old stock unhardened pushrods.